Quantification of the degradation products of sevoflurane in two CO2 absorbants during low-flow anesthesia in surgical patients. Sevoflurane, a new inhalational anesthetic agent has been shown to produce degradation products upon interaction with CO2 absorbants. Quantification of these sevoflurane degradation products during low-flow or closed circuit anesthesia in patients has not been well evaluated. The production of sevoflurane degradation products was evaluated using a low-flow anesthetic technique in patients receiving sevoflurane anesthesia in excess of 3 h. Sevoflurane anesthesia was administered to 16 patients using a circle absorption system with O2 flow of 500 ml/min and average N2O flow of 273 ml/min. Preoperative and postoperative hepatic and renal function studies were performed. Gas samples were obtained from the inhalation and exhalation limbs of the anesthetic circuit for degradation product analysis and analyzed by gas chromatography/mass spectrometry for four degradation products. The first eight patients received sevoflurane anesthesia using soda lime, and the following eight patients received anesthesia using baralyme as the CO2 absorbant. CO2 absorbant temperatures were measured during anesthesia. Of the degradation products analyzed, only one compound [fluoromethyl-2, 2-difluoro-1-(trifluoromethyl) vinyl ether], designated compound A, was detectable. Concentrations of compound A increased during the first 4 h of anesthesia with soda lime and baralyme and declined between 4 and 5 h when baralyme was used. Mean maximum inhalation concentration of compound A using baralyme was 20.28 +/- 8.6 ppm (mean +/- SEM) compared to 8.16 +/- 2.67 ppm obtained with soda lime, a difference that did not reach statistical significance. A single patient achieved a maximal concentration of 60.78 ppm during low-flow anesthesia with baralyme. Exhalation concentrations of compound A were less than inhalation concentrations, suggesting patient uptake.(ABSTRACT TRUNCATED AT 250 WORDS)


Intelligent alarms reduce anesthesiologist's response time to critical faults. The proliferation of monitors and alarms in the operating room may lead to increased confusion and misdiagnosis unless the information provided is better organized. Intelligent alarm systems are being developed to organize these alarms, on the assumption that they will shorten the time anesthesiologists need to detect and correct faults. This study compared the human response time (the time between the sounding of an alarm and the resolution of a fault) when anesthesiologists used a conventional alarm system and when they used an intelligent alarm system. In a simulated operating room environment, we asked 20 anesthesiologists to resolve seven breathing circuit faults as quickly as possible. Human response time was 62% faster, decreasing from 45 to 17 s, when the intelligent alarm system was used. The standard deviations in response time were only half as large for the intelligent alarm system. It appears that the computer-based neural network in the intelligent alarm system diagnosed faults more rapidly and consistently than did the anesthesiologists. This study indicates that breathing circuit faults may be more rapidly corrected when the anesthesiologist is guided by intelligent alarms.


Radiologic localization of the laryngeal mask airway in children. In the absence of data on the anatomic localization of the cuff of the laryngeal mask airway (LMA) in children, radiologic images were obtained from 50 infants and children (aged 1 month to 15 yr) undergoing diagnostic radiologic procedures during halothane and N2O:O2 anesthesia. In 46 patients, the cuff of the LMA was in the pharynx and covered the laryngeal opening. The upper (proximal) section was adjacent to the base of the tongue at the level of C1 or C2 vertebrae pushing the tongue forward and its lower (distal) end was in the inferior recesses of the hypopharynx at the levels of C4 to T1 vertebrae. The cuff of LMA at this position between the base of the tongue above the epiglottis and below the laryngeal opening, covered the laryngeal aperture, forming a low pressure seal at the entrance of the larynx. In 37 of these 46 patients, a posterior deflection of the epiglottis was noted (< 45 degrees), and in only 9, the epiglottis was in the anatomic position. In four patients, the cuff of the LMA was located in the oropharynx. No correlation was found between the size of the LMA and the position of the epiglottis with respect to end-tidal CO2, respiratory rate, or the leak pressures. The size of the LMA, its anatomic location, and the position of the epiglottis had no significant effect on the respiratory parameters of spontaneously breathing children.


Anesthetic techniques during surgical repair of femoral neck fractures. A meta-analysis. Fracture of the hip typically occurs in older women. These patients usually have serious accompanying chronic illnesses. There is a difference of opinion as to the choice of regional versus general anesthesia for surgery in these patients. This meta-analysis compared survival of patients with traumatic femoral neck fractures undergoing operative repair during regional or general anesthesia. The data sources were articles comparing regional and general anesthesia from peer reviewed journals. Thirteen randomized controlled trials were found. Besides 1-month mortality, variables used were estimated operative blood loss and the incidence of deep venous thrombosis. For dichotomous outcomes, two effect measures were calculated: the difference in probabilities and the odds ratio. For blood loss, a continuous variable, the effect measure was the mean difference in blood loss. A random-effects Bayesian meta-analysis was used to combine study data, estimate parameters and create 95% confidence intervals. Only the incidence of deep venous thrombosis was clearly greater for patients receiving general anesthesia, being 31 percentage points higher than for patients receiving regional anesthesia. By the odds ratio, deep venous thrombosis was almost four times more likely following general anesthesia. There was no difference in estimated operative blood loss. By probability difference, mortality was a non-significant 2.7 percentage points less following regional anesthesia. By odds ratio effect measure, death was 1.5 times more likely following general anesthesia, but the lower bound of the 95% confidence interval was close to 1. Meta-analysis does not allow a conclusion that important differences in mortality exist between regional and general anesthesia for traumatic hip fracture surgery.


Duration of apnea in anesthetized infants and children required for desaturation of hemoglobin to 95%. The influence of upper respiratory infection. Sixty-one patients ASA physical status 1-2 aged 1 month to 12 years undergoing elective surgery were included in the study. Anesthesia was induced via a mask with sevoflurane up to 5% and 66% nitrous oxide in oxygen. After paralysis with vecuronium (0.12 mg/kg iv), the trachea was intubated and the lungs were ventilated manually with 3% sevoflurane in oxygen until the end-tidal nitrous oxide decreased to less than 5%. Apnea was started by disconnecting the breathing circuit from the endotracheal tube. The time from the start of apnea to Spo2 of 95% was measured. Manual ventilation was reinstituted when Spo2 decreased to 95% and another set of vital signs was recorded. Twenty of 61 patients had symptoms of upper respiratory infection. The time to Spo2 of 95% correlated well with height, age, and body weight both by linear and non-linear regression analyses. The patients with symptomatic upper respiratory infection required less time for Spo2 to decrease to 95% compared to the asymptomatic children. We conclude that younger children require less time for Spo2 to decrease to 95%. The presence of upper respiratory infection is an additional factor increasing the susceptibility of small children to hypoxemia.


A randomized comparison of intravenous versus lumbar and thoracic epidural fentanyl for analgesia after thoracotomy. Administration of large doses of fentanyl is a popular method to provide postoperative analgesia after thoracotomy. It is however unclear whether epidural lumbar (L) or epidural thoracic (T) administration of fentanyl confers any major advantage over intravenous (iv) infusion. Using a randomized prospective study design, we compared the potential benefits of L, T, and iv fentanyl administration after thoracotomy in 50 patients. Epidural catheters were not injected during surgery. Postoperatively a fentanyl infusion (5 micrograms/ml) was started at 1 microgram.kg-1.h-1 after a bolus of 1 microgram/kg and adjusted to maintain a score < or = 30/100 at rest using a visual analog scale (VAS) for pain. Data were prospectively collected before surgery, at fixed intervals during the 48 h of fentanyl infusions, and the day of discharge. There was no difference between the groups in overall quality of analgesia at rest and after coughing, quantity of fentanyl delivered (L = 1.15 +/- 0.38, T = 1.22 +/- 0.23, iv = 1.27 +/- 0.3 micrograms.kg-1.h-1), incidence of pruritus needing treatment (L = 2, T = 1, iv = 0 patients), need to decrease fentanyl infusion rate because of side effects (L = 2, T = 2, iv = 4 patients), importance of pulmonary infiltrates, or arterial blood gas values. One patient (L group) needed naloxone (0.04 mg iv). Intravenous patients were more frequently nauseated (P = .009) and needed boluses of fentanyl more often (L = 3 +/- 9, iv = 6 +/- 12, T = 4 +/- 8; P = .04).(ABSTRACT TRUNCATED AT 250 WORDS)


Does a subanesthetic concentration of isoflurane blunt the ventilatory response to hypoxia? The normal ventilatory response to the sudden imposition of sustained hypoxia is characterized by an acute increase followed by a modest decline in ventilation. Since subanesthetic concentrations of potent inhalational anesthetics greatly attenuate the acute response, we hypothesized that ventilation might decrease to less than normoxic levels when hypoxia is sustained. We therefore measured the ventilatory response to 20 min of sustained hypoxia (PETO2 45 mmHg) at two levels of strict isocapnia--normocapnia (PETCO2 1-2 mmHg above resting) and hypercapnia (PETCO2 49 mmHg)--in eight healthy male subjects during inhalation of 0.1 MAC isoflurane or carrier gas (control). An abrupt end-tidal step from normoxia to isocapnic hypoxia was induced using a dynamic end-tidal forcing system. Isoflurane and control experiments were performed on separate days; the order of isoflurane and control days and the order of normocapnia and hypercapnia within days were randomized. Subjects were studied while fasted, always at the same time of day, and were required to watch a documentary videotape to minimize differences in level of consciousness. With normocapnia, there was no difference in ventilation at any time between isoflurane and control (prehypoxic 9.6 +/- 1.5 vs. 9.5 +/- 2.6 1/min, peak hypoxic 24.7 +/- 10.4 vs. 26.2 +/- 10.4 1/min, final hypoxic 15.0 +/- 4.4 vs. 15.9 +/- 3.5 1/min; mean +/- SD). With hypercapnia, prehypoxic ventilation increased to the same level for isoflurane and control (24.8 +/- 6.7 vs. 24.8 +/- 9.6 1/min). Although peak hypoxic ventilation was slightly less in isoflurane than in control hypercapnic experiments, this was not significant (49.6 +/- 16.3 vs. 56.5 +/- 24.3 1/min; P = .22).(ABSTRACT TRUNCATED AT 250 WORDS)


Comparison of postoperative analgesic effects of intraarticular bupivacaine and morphine following arthroscopic knee surgery. Recent studies have shown that, in the presence of inflammation, the local administration of opioids results in analgesia. The analgesic efficacy of local anesthetics and morphine administered intraarticularly was compared in patients undergoing arthroscopic knee surgery under epidural anesthesia. We compared postoperative pain scores (VAS) and opioid requirements among 47 patients receiving, in a randomized, double-blinded fashion, one of three intraarticular medications (20 ml): normal saline with 100 micrograms epinephrine (group 1, n = 16); 0.25% bupivacaine with 100 micrograms epinephrine (group 2, n = 15); and 3 mg morphine sulfate and 100 micrograms epinephrine in normal saline (group 3, n = 16). VAS scores were similar in the groups preoperatively and on arrival in the recovery room. At the end of the first postoperative hour, the residual sensory blockade was minimal in all three groups (mean = 3.8-4.1 segments) and almost total recovery occurred in all three groups before the second postoperative hour. The VAS in group 3 was not significantly different than group 1 at any time interval. Intraarticular bupivacaine (group 2) provided significantly better analgesia than did saline or morphine (group 1 or 3) in the first 2 postoperative hours (ANOVA, P < .05). Subsequent VAS scores were not significantly different in the three groups. While no patient in group 2 requested analgesics during the first postoperative hour, nine patients in group 3 required systemic analgesics (P < .01). We conclude that no evidence for a peripheral opiate-receptor mediated analgesia could be demonstrated in patients undergoing arthroscopic knee surgery under epidural anesthesia.


Reaction of sevoflurane and its degradation products with soda lime. Toxicity of the byproducts. Sevoflurane previously has been reported to undergo extensive degradation in the presence of soda lime. To more completely characterize the extent and significnce of this reaction, we studied degradation of sevoflurane with and without soda lime, as well as the toxicity and mutagenicity of the degradation products. Two degradation products detected were CF2 = C(CF3)OCH2F (compound A) and CH3OCF2CH(CF3)OCH2F (compound B). During circulation of 1%, 2%, and 3% sevoflurance in a closed anesthesia circuit for 8 h, peak concentrations of compound A were 13.3 +/- 0.27, 30.2 +/- 0.10, and 42.1 +/- 1.07 ppm at 2 h, respectively. The concentrations of compound B did not exceed 2 ppm. The temperature of the soda lime was 43.3 +/- 2.8 degrees C at 1 h and increased gradually to 47.9 +/- 1.5 degrees C after 8 h. In closed flasks with soda lime, the magnitude of the decrease in sevoflurance concentrations (3%) and of the increase in compound A concentrations was temperature dependent. The peak concentrations of compound A at 23 degrees C, 37 degrees C, and 54 degrees C were 32.8 +/- 6.8 at 2 h, 46.6 +/- 1.0 at 0.5 h, and 78.5 +/- 2.3 ppm at 0.5 h, respectively. The LC50 (50% lethal concentration) of compound A in Wistar rats was 1,090 ppm in males and 1,050 ppm in females exposed for 1 h. The LC50 was 420 ppm in males and 400 ppm in females exposed for 3 h. The chronic toxicity of compound A in Wistar rats was studied by exposing rats 24 times, for 3 h each, to initial concentrations of 30, 60, or 120 ppm in a ventilated chamber. At all concentrations, there were no apparent effects other than a loss of body weight in females (120 ppm) on the final day (P < 0.01). Compound A did not induce mutation on the reverse (Ames) test at less than 2,500 micrograms/dish (culture medium 2.7 ml) with activation by S-9 mixture, and below 1,250 micrograms/dish (culture medium 2.7 ml) without activation, in four strains of S. typhimurium and in 1 strain of E. coli. Exposure of fibroblasts to 7,500 ppm of compound A for 1 h, compound A did not induce structural change. In a study of acute toxicity of compound B, there was no toxicity in Wistar rats after 3 h of exposure at 2,400 ppm. The reverse (Ames) test for compound B was negative at 625-1,250 micrograms/dish.(ABSTRACT TRUNCATED AT 400 WORDS)


The influence of hemorrhage on organ perfusion during deliberate hypotension in rats. There is general concern that major blood loss during deliberate hypotension could produce severe organ ischemia, but documentation of the magnitude of this response remains obscure. To examine this response, we studied 43 male Sprague-Dawley rats that were divided into seven groups: the control animals received 1 MAC (1.4%) isoflurane only; the hypotensive animals received a 1.4% isoflurane baseline anesthetic and were then rendered hypotensive by either increasing the isoflurane concentration (dISO), or by adding sodium nitroprusside (SNP), or 2-chloroadenosine (2AD) to the baseline anesthetic, decreasing the MAP to 51 mmHg; hemorrhaged animals had hypotension produced in the same manner as for the hypotensive animals, but additionally were bled 20% of estimated blood volume during deliberate hypotension produced with either deep isoflurane (dISOH), sodium nitroprusside (SNPH), or 2-chloroadenosine (2ADH). After a 25-min period of hypotension, or hypotension plus hemorrhage, cardiac output and blood flow to brain, heart, gastrointestinal tract, kidney, and liver were measured with 141Ce-labelled 15-microns microspheres. Hypotension was associated with decreased blood flow to the kidneys in all groups and to the liver in the 2AD group and an increased blood flow to the heart in the SNP and 2AD groups. Hemorrhage decreased blood flow during deliberate hypotension to the brain and the gastrointestinal tract in the dISOH and 2ADH groups and to the liver in the dISOH group. Our results suggest that hemorrhage during deliberate hypotension with dISO or isoflurane plus 2AD may be associated with compromised organ blood flow, whereas blood flow to vital organs is maintained after 20% hemorrhage during isoflurane and superimposed SNP-induced hypotension.


Endothelium-dependent circulatory control--a mechanism for the differing peripheral vascular effects of isoflurane versus halothane. Several studies have suggested that halothane and isoflurane modify responses to endothelium-dependent vasodilators, indicating that the differing circulatory effects of these anesthetics may be, in part, attributable to alterations in endothelial cell control of vascular tone. This study was designed to determine the contribution of endothelium-derived relaxing factor (EDRF/NO) to circulatory control in indomethacin-treated rats anesthetized with equipotent concentrations (1 MAC) of either isoflurane (n = 6) or halothane (n = 8). Using radiolabelled microspheres, systemic and regional hemodynamics were measured in cerebrum, cerebellum, heart, kidney, gastrointestinal tract, spleen, liver, skeletal muscle, skin, ear, and white and brown fat. Cardiac output, mean arterial pressure (MAP), systemic vascular resistance (SVR), regional blood flows, and regional vascular resistances were determined before (control) and after administration of NG-monomethyl-L-arginine (L-NMMA, 100 mg/kg) to inhibit EDRF/NO synthesis, and following L-arginine (300 mg/kg) to reverse the effects of L-NMMA. In both anesthetic groups, L-NMMA decreased cardiac output and increased MAP, SVR, and regional resistances in brain, heart, kidney, spleen, gastrointestinal tract, hepatic artery, skeletal muscle, skin, and white fat. L-arginine returned SVR and MAP to or below control values in both groups, although cardiac output remained decreased. During isoflurane as compared to halothane anesthesia, L-NMMA caused significantly greater increases in blood pressure (54 +/- 7% vs. 24 +/- 2%) and SVR (143 +/- 22% vs. 79 +/- 11%). In addition, rats anesthetized with isoflurane had significantly greater increases in vascular resistance in heart, kidney, gastrointestinal tract, hepatic artery, and skin after L-NMMA than did rats anesthetized with halothane.(ABSTRACT TRUNCATED AT 250 WORDS)


Interaction of intrathecal morphine with bupivacaine and lidocaine in the rat. The interaction in the rat between intrathecal morphine and local anesthetics (bupivacaine and lidocaine) on nociception (52.5 degrees C hot plate and paw pressure), motor function, and autonomic function (blood pressure [BP] and heart rate [HR]) was examined over a range of doses for both morphine and the local anesthetics. High doses of intrathecal bupivacaine (75 micrograms) or lidocaine (500 micrograms) produced motor block and hypotension (150 micrograms bupivacaine) lasting approximately 15 and 7 min, respectively, whereas low doses of intrathecal bupivacaine (25 micrograms) and lidocaine (100 micrograms) produced only a transient motor weakness lasting 2 min or less. Alone, neither agent altered the hot plate or paw pressure response at doses, or at times, where the agents had no effect upon motor function. In contrast, at the low dose of either local anesthetic, after the resolution of the transient motor weakness, these doses resulted in a significant leftward shift in the dose-response curves for intrathecal morphine on both the hot plate and paw pressure, as measured by the maximum observed peak effect and by the area under the time-effect curve. Thus, for example, the morphine ED50 (95% confidence intervals) for morphine/saline was 1.7 micrograms (0.7-1.9) on the hot plate and 1.1 micrograms (0.8-1.4) on the paw pressure versus for morphine/bupivacaine (25 micrograms): hot plate 0.25 micrograms (0.21-0.42) and paw pressure 0.28 micrograms (0.2-0.4). Intrathecal morphine was not observed to have any effect on the dose-dependent effects of intrathecal bupivacaine on motor or autonomic blockade. Comparable results were also observed with lidocaine (bupivacaine was found to have no significant effect on spinal cord morphine clearance). We conclude that low doses of intrathecal lidocaine and bupivacaine, which alone have no antinociceptive effect, at times when motor function was clearly unimpaired, are able to significantly augment the antinociceptive activity of intrathecal morphine on the hot plate and paw pressure tests. This prominent and selective potentiation appears to occur via a non-pharmacokinetic mechanism and probably reflects upon the interaction of low concentrations of local anesthetics with systems in the spinal dorsal horn that process acute high threshold afferent input.


Metabolism of ketamine stereoisomers by human liver microsomes. Ketamine is used clinically as a racemic mixture of optical isomers that differ in their analgesic properties and psychomimetic effects. Administered individually, or together as the racemate, ketamine enantiomers differ in their hepatic clearance and duration of anesthetic effect. S(+) ketamine exhibits a greater clearance and faster anesthetic recovery compared to the racemate and a greater clearance compared to R(-) ketamine. Ketamine undergoes extensive hepatic metabolism, primarily via N-demethylation to norketamine, yet little is known about the human metabolism of ketamine enantiomers. The purpose of this investigation therefore was to characterize ketamine racemate and enantiomer metabolism by human liver and to test the hypothesis that differences in hepatic ketamine enantiomer metabolism can account for observed differences in ketamine enantiomer pharmacokinetics. Ketamine N-demethylation by microsomes from three human livers was measured by gas chromatography-mass spectrometry. At ketamine concentrations typically achieved during anesthesia (5 microM), the rate of S(+) ketamine demethylation was 20% greater than that of R(-) ketamine and 10% greater than that of the racemate (P < .05). At all ketamine concentrations, the rate of racemate demethylation was less than the sum of the rates for the individual enantiomers, reflecting a metabolic enantiomeric interactin whereby one ketamine enantiomer inhibits the metabolism of the other enantiomer. N-demethylation of racemic ketamine and each enantiomer was catalyzed by two apparent enzymes, a high affinity-low capacity enzyme (Km1 30-50 microM, Vmax1 2-6 nmoles.min-1 x nmole-1) and a low affinity-high capacity enzyme (Km2 600-800 microM, Vmax2 9-15 nmoles.min-1 x nmole-1).(ABSTRACT TRUNCATED AT 250 WORDS)


The fast flush test measures the dynamic response of the entire blood pressure monitoring system. The fast flush test (FT) is the only test that allows clinicians to determine in vivo the natural frequency (fn) and damping coefficient (zeta) of an invasive blood pressure monitoring system. The underlying assumption to the validity of the FT is that it activates the whole system including the distal catheter. We devised an in vitro model of a typical invasive blood pressure monitoring system to determine whether this assumption was true. The model consisted of a conventional transducer with a flush device attached to various lengths of connecting tubing (91.4, 182.9, and 274.3 cm) terminated by four different diameter catheters (5.1 cm 14 G, 16 G, 18 G, and 20 G). A microtipped transducer catheter was inserted into the distal catheter tubing system. A FT was performed and the fn and zeta were recorded from the conventional transducer and simultaneously from the microtipped transducer catheter. Similar studies were conducted using the ROSE damping device as well as with systems including 0.1 ml of air near the conventional transducer. These studies utilized 18- and 20-G catheters with each of the three lengths of connecting tubing. All measurements of fn and zeta at the proximal conventional transducer were identical to those measurements as recorded by the distal microtipped transducer catheter. We conclude that the FT activates the whole monitoring system and that fn and zeta are the same throughout the system including the distal catheter.


Diet-induced atherosclerosis in cynomolgus monkey aorta and regression by the sixth-month observation. Pathomorphologic analysis was employed to evaluate diet-induced atherosclerosis in cynomolgus monkey aorta and regression by administration of a hypolipidemic agent for six months after the atherogenic ration. Twenty-seven male cynomolgus monkeys were divided into three groups. Group A was fed individually with a high-fat diet containing 0.3% cholesterol under identical conditions for six months. Group B was fed with normal monkey chow for six months after the same atherogenic ration. Group C was fed with normal monkey chow and administered a hypolipidemic agent 1% of 4-[2-(4-isopropylbenzamido)ethoxy] benzonic acid for six months after the same atherogenic ration. Each thoracic and abdominal aorta of animal models was separately analyzed. Lipid composition analysis and esterified cholesterol (CE) in aortic wall, ratio of free cholesterol to phospholipid, surface involvement, and atherosclerotic index after Sudan IV staining were studied for evaluation of progression and regression. The configurations of atherosclerotic involvement were histologically evaluated among each group. These observed lesions, features specific to cynomolgus lesions, mainly consisted of lipid-rich foam cells, lipid debris, and proliferated extracellular matrix. No different lesion composition was noted between the thoracic and abdominal aorta. This may suggest that some local factors play an important role for development of atherosclerosis after the initial event. Group C had remarkable reduction of foam cells and of CE accumulation in both the thoracic and abdominal aortic wall. Accelerated regression in group C as compared with group B was demonstrated both biochemically and pathohistologically. These results suggest that substantial regression of atherosclerosis in both the thoracic and abdominal aorta can be expected. This hypolipidemic agent exerts notable antiatherosclerotic activity, along with a lowering effect on plasma total cholesterol levels.


Long-term clinical and duplex follow-up after proximal vertebral artery reconstruction. From 1977 to 1989, 28 patients, 18 men and 10 women, underwent 29 proximal vertebral artery reconstructions. Indications were vertebrobasilar insufficiency in 17 patients and TIA or stroke in 6. Five were asymptomatic. Procedures performed were endarterectomy in 20, reimplantation in 5, venous bypass in 3, and decompression in 1 case. Concomitant procedures were coronary artery bypass grafting (6) and carotid, subclavian, or innominate artery revascularization (14). There was no operative mortality. There were 3 early reoperations for occlusion, bleeding, and lymph fistula, respectively. Except for 1 foreign patient recent clinical follow-up was complete. Mean follow-up was 85.6 months (range 17-146). During follow-up 10 patients died. Causes were mainly cardiac (3), carcinoma (3), and stroke (2). Seventeen patients were alive, 13 had no cerebrovascular symptoms, 2 sustained a hemispherical stroke, 1 was only slightly improved, and 1 had a drop attack 131 months after operation. Five and ten-year actuarial survival rates were 85% and 51% respectively. Follow-up with duplex scan was available in 26 patients and was complete in 24. Mean duplex follow-up was 78.6 months (range 3-146). Significant abnormalities were noted in 6 but with symptoms in only 1 patient. Mean time to restenosis was 77.3 months. Late angiographic control in 10 patients correlated well with duplex findings. Proximal vertebral artery reconstruction yields good clinical long-term results, and duplex scan is a useful tool in the follow-up of these patients.


Capillary blood flow to the skin of forearm in cirrhosis. In liver cirrhosis a hyperkinetic circulatory state is frequently observed as a consequence of an arterial or even a venous peripheral vasodilatation with secondary increase in cardiac output. Indirect evidence suggests that, in liver disease, the manifestation of warm hands, capillary pulsation, or palmar erythema may also relate to such a state by way of an increased skin blood flow. The purpose of the present study has been to directly assess capillary skin blood flow in liver disease through the clearance of a locally injected radioactive substance. The study was performed in 24 patients with different liver diseases, including 14 Child class II cirrhotics, and in 9 control subjects. A small volume of Na 131I solution was injected at the volar surface of the forearm, and radioactive counts were recorded continuously for ten seconds every minute for up to twenty minutes. The best fit line of the disappearance rate was determined by the least square method, and both its T/2 and an estimated blood flow parameter were calculated. The T/2 of isotope disappearance rate was 4.54 +/- 0.71 and 4.38 +/- 0.68 minutes in cirrhotics and controls, respectively. Similarly, estimates of skin blood flow (mL/min/100 g tissue) were 7.82 +/- 1.28 in the cirrhotic patients, not significantly different from those in both patients with mixed liver diseases (7.6 +/- 2.86) and control subjects (8.06 +/- 1.04). Parameters of skin blood flow were also invariant in respect to the various etiologies of liver disease. Thus, the present findings indicate that capillary skin blood flow is not affected by the hyperdynamic circulatory changes occurring in liver cirrhosis.(ABSTRACT TRUNCATED AT 250 WORDS)


Failure of thrombin-antithrombin III complexes in the diagnosis of deep vein thrombosis. Plasma thrombin-antithrombin III (T-AT) complexes are reputed to be an indirect manifestation of thrombin generation, and a role for their determination in the diagnosis of deep vein thrombosis (DVT) has been advocated. In order to evaluate the accuracy of T-AT complexes assay for DVT diagnosis, in 166 consecutive outpatients with clinical suspicion of the disease, plasma concentration of T-AT complexes was measured immediately before venography by means of an enzyme-linked immunosorbent assay kit. The result of the T-AT complexes assay was elevated in 29 of the 48 patients with DVT (sensitivity, 60%). The T-AT complexes levels were within the normal range in 104 of the 118 patients with normal venograms (specificity, 88%). The positive and the negative predictive value were 67% and 85%, respectively. The authors conclude that the T-AT complexes assay is of little value for the diagnosis of DVT in outpatients.


Automated blood pressure determination during exercise test. Clinical evaluation of a new automated device. The accuracy and reproducibility of a new automatic device (P) specially designed for noninvasive blood pressure monitoring during the exercise stress test were evaluated in 50 consecutive subjects (34 normotensives and 16 hypertensives). Automatic measurements were compared with those taken by a sphygmomanometer (RR). A good agreement between systolic pressure values obtained by the two methods was found (RR 159 +/- 30 mmHg, P 158 +/- 28 mmHg, mean difference = -1.53 +/- 13 mmHg, p = 0.166, ns). On the contrary the new device significantly underestimated diastolic pressure values (RR 89.3 +/- 13 mmHg; P 84 +/- 13 mmHg, mean difference -5.37 +/- 9.3, p < 0.001). In conclusion the new device seems able to measure systolic but underestimates diastolic blood pressure both in hypertensives and in normotensives during the effort test.


Hazardous information from bedside fast-flush device test for fluid-filled pressure monitoring systems. The fast-flush device test--based on the square-wave principle--has been used in clinical practice to test the accuracy of fluid-filled pressure-monitoring systems. One assumption with the square-wave test is that the system is a second-order approximation. To elucidate the problem, the authors compared, in vitro, a reference test method (frequency response test), valid for second-order systems, with a pure square-wave test and a fast-flush device test. They showed that the two tested systems did not have any relation to the reference system, which suggests that the second-order approximation is not valid. Therefore, the fast-flush device test cannot be used reliably in testing the total chain of catheter, tubing, transducer, and monitor for invasive pressure measurement.


Inhibition of interleukin 1-mediated proteoglycan degradation in bovine articular cartilage explants by addition of sodium hyaluronate. The effect of exogenous hyaluronate on normal cartilage metabolism and interleukin-1 (IL-1)-induced cartilage matrix degradation was investigated in a bovine cartilage explant culture system. Addition of hyaluronate at a concentration of 1.5 mg/ml to cartilage culture explants consistently decreased normal proteoglycan release from the matrix to a value less than that found in control cultures. Addition of 1.5 mg of hyaluronate/ml to IL-1 stimulated cartilage culture systems reduced proteoglycan release from the matrix by 83 to 113%. The reduction in control and IL-1-stimulated proteoglycan degradation by hyaluronate had a concentration-dependent trend. Evaluation of alterations in protein (enzyme) release by IL-1-stimulated chondrocytes after introduction of hyaluronate was evaluated by use of sodium dodecyl sulfate agar gel electrophoresis of cartilage-conditioned media. The quantity or the molecular weight profile of IL-1-induced proteins did not differ after introduction of hyaluronate into the culture system. Results indicate that introduction of high molecular weight hyaluronate into cartilage culture systems results in a decrease in proteoglycan release from the matrix in control systems, as well as in cultures incubated with IL-1. Because IL-1-stimulated protein synthesis by chondrocytes remains unchanged after addition of exogenous hyaluronate, the mechanism of inhibition of matrix degradation does not appear to be interference with binding of IL-1 to chondrocytes or to be inhibition of the production of neutral metalloproteases, including stromelysin.


Physiologic effects of administration of interleukin 1 beta in cows. The immunomodulating polypeptide interleukin 1 beta (IL-1 beta) has been shown to be homologous to osteoclast-activating factor and is capable of stimulating increased osteoclastic bone resorption. This effect prompted an investigation into the potential use of IL-1 beta for prevention of parturient paresis, a disease of dairy cows characterized by hypocalcemia and poor osteoclastic resorption of bone. Six nonpregnant cows were treated with a high dosage of IL-1 beta (166 ng/kg of body weight) every 8 hours for 4 days. The IL-1 beta treatment significantly (P < 0.05) increased urinary hydroxyproline excretion, an index of osteoclast activity, indicating that bone calcium resorption might be stimulated by IL-1 beta treatment of cows. However, IL-1 beta treatment also caused transient fever, inappetence, increased pulse and respiratory rate, and diuresis. The acute, but transient, effect of IL-1 beta treatment was to cause a decrease in plasma calcium and phosphorus concentrations. The pleiotropic effects of IL-1 beta administration negated the positive effects on osteoclastic bone resorption, and indicates that this cytokine may be of minimal benefit for prevention of parturient paresis.


Cross-reactivity between a monoclonal antibody that recognizes a tumor-associated antigen on bovine lymphosarcoma cells and blood lymphocytes from various mammalian species. Tumor-associated antigens that are expressed in lymphosarcoma B cells of cattle with enzootic bovine leukosis had been analyzed in terms of their reactivity with 13 monoclonal antibodies (MAB). By use of flow cytometry and radioimmunoprecipitation, 1 of the MAB (c143) that recognized a tumor-associated antigen cross-reacted with blood lymphocytes (BL) from various mammalian species. By use of flow cytometry, the c143 MAB reacted with 10 to 49% of BL derived from human beings, mice, dogs, horses, pigs, llamas, sheep, goats, and cattle. Titer of the c143 MAB with BL from horses, pigs, human beings, and llamas ranged between 1:6.0 x 10(4) and 1:5.3 x 10(5); titer associated with BL of goats and sheep was 1:1.6 x 10(6); and that associated with BL of cattle was 1:4.3 x 10(7). The c143 MAB specifically immunoprecipitated 3 homologous proteins from cell extracts of caprine, ovine, and bovine BL (32-, 34-, and 36- to 37-kDa bovine proteins; 31-, 32-, and 36- to 37-kDa caprine proteins; and 31.5-, 33-, and 36- to 37-kDa ovine proteins), but none was immunoprecipitated from human, murine, canine, porcine, and llama BL. These results indicate that the avidity of the c143 MAB in binding to BL from ruminants (eg, goats, sheep, and cattle) is higher than that to BL from human beings, mice, dogs, horses, pigs, and llamas. In sheep, the c143 MAB could immunoprecipitate the aforementioned proteins from BL of the Suffolk breed, but not BL from the Corriedale breed, whereas the c143 MAB immunoprecipitated apparently identical proteins from BL of 4 breeds of cattle.


Evaluation of a modified-live virus vaccine administered in ovo to protect chickens against Newcastle disease. The B1 strain of Newcastle disease virus (NDV-B1), which is nonpathogenic for newly hatched chickens, killed embryos when it was used to inoculate chicken eggs at embryonation day 18. Treatment of NDV-B1 with an alkylating agent, ethylmethane sulfonate (EMS) markedly reduced the pathogenicity of the virus for 18-day-old chicken embryos. Eggs inoculated with the modified virus (NDV-B1-EMS) hatched, and the virus was isolated from lungs and spleen of 1-day-old chickens. The hatched chickens developed antibody to NDV and were protected against challenge exposure (at 4 weeks of age) with a highly virulent GB-Texas strain of NDV. Presence of maternal antibody to NDV in embryonating eggs did not influence the protective ability of NDV-B1-EMS, which also induced protective immunity when administered to 4-week-old chickens. The 50% protective dose of NDV-B1-EMS in maternal antibody-negative and -positive embryos was calculated to be 10.77 and 17.70 embryo 50% lethal doses, respectively. Results of the study indicated that NDV-B1-EMS may be used as an embryo vaccine to protect chickens against Newcastle disease.


Protection of neonatal calves against fatal enteric colibacillosis by administration of egg yolk powder from hens immunized with K99-piliated enterotoxigenic Escherichia coli. The protective effects of egg yolk powder prepared from hens vaccinated with heat-extracted antigens from K99-piliated enterotoxigenic Escherichia coli (ETEC) strain 431 were evaluated in a colostrum-fed calf model of ETEC-induced diarrhea caused by a heterologous strain (B44). The antibody powder was obtained by spray-drying the water-soluble protein fraction of egg yolks after removing the lipid and fatty components by precipitation with hydroxypropylmethylcellulose phthalate. A total of 16 colostrum-fed calves were studied to determine whether the orally administered antibody powder would prevent fatal bovine colibacillosis caused by a virulent ETEC strain. Clinical response of individual calves was monitored and evaluated in the context of these variables: fecal consistency score, intestinal colonization, weight loss, and mortality. Control calves that were treated with vehicle (milk with egg yolk powder from nonimmunized hens) had severe diarrhea and dehydration and died within 72 hours after infection was manifested. In contrast, calves fed milk containing egg yolk powder with antipili agglutinin titers of 1:800 and 1:1,600 had transient diarrhea, 100% survival, and good body weight gain during the course of the study. Results indicate that the orally administered egg yolk powder protected against ETEC-induced diarrhea in neonatal calves and that the protective components may have been the antibodies raised by vaccination of chickens against ETEC.


Effects of clinically apparent and subclinical Ostertagia ostertagi infections on nitrogen and water metabolism in calves. Four balance trials were conducted in 3 groups of 5 calves each at 0, 4, 8, and 14 weeks after initial inoculation with Ostertagia ostertagi. Group-1 calves were inoculated with 100,000 third-stage larvae (L3) of O ostertagi/wk for 14 weeks. Group-2 calves were inoculated with 10,000 L3/wk for 14 weeks, and group-3 calves were not inoculated. Effects of infection on apparent digestibilities of dry matter and nitrogen, and balances of nitrogen and water were evaluated. Neither clinically apparent (group 1) nor subclinical (group 2) O ostertagi infections had observable effects on the apparent digestibility of dry matter. Subclinical infection also had no significant effects on nitrogen digestibility or nitrogen and water balance. Clinically apparent infection, however, decreased the apparent digestibilities of nitrogen significantly (P < 0.05) at 4, 8, and 14 weeks after inoculation, and decreased nitrogen balance at 4 and 8 weeks after inoculation. Group-1 calves also had lower water intake, fecal-water excretion, and apparent water balance, but higher urinary water output at 4, 8, and 14 weeks after inoculation.


Nutritional and pathophysiologic effects of clinically apparent and subclinical infections of Ostertagia ostertagi in calves. Nutritional and physiologic effects of clinically apparent and subclinical Ostertagia ostertagi infections were studied in 3 groups of 5 calves each. Group-1 calves were inoculated with 100,000 Ostertagia ostertagi third-stage larvae (L3)/calf/wk for 14 weeks. Group-2 calves were inoculated with 10,000 L3/calf/wk for 14 weeks, and group-3 calves were no inoculated. Calves in group 1 had decreased dry matter intake and feed utilization from 4 weeks after initial inoculation. Group-2 calves had no changes in dry matter intake, but had decreased feed utilization at 12 and 14 weeks. Calves with clinically apparent infections (group 1) lost a mean weight of 11.8 kg, whereas calves with suclinical infections (group 2) lost a mean of 46.6 kg, and control calves lost a mean of 60.7 kg. Calves with O ostertagi infections (group 1 and 2) also had decreased carcass quality at slaughtering, which was reflected in decreased dressing weights and increased water-holding capacity of the rib-eye muscle. Calves in groups 1 and 2 also had lower carcass yield and rib-eye muscle weight, and group-1 calves had decreased protein content. Results of hematologic, pathologic, parasitologic, and clinical examinations mirrored nutritional changes.


Effects of Ostertagia ostertagi infection on secretion of metabolic hormones in calves. Effects of Ostertagia ostertagi infection on secretion of insulin, pancreatic glucagon, cortisol, gastrin, and pepsinogen were studied in calves inoculated with 100,000 (group 1) or 10,000 (group 2) O ostertagi infective larvae weekly for 14 weeks. Plasma insulin concentrations in both inoculated groups were lower than those in a non-infected (group 3) control group. The differences between group 1 and group 3 were significant (P < 0.05) at 2 and 12 weeks after initial inoculation. Plasma pancreatic glucagon and cortisol concentrations of groups 1 and 2 did not differ significantly from those of the control group, although plasma pancreatic glucagon concentration was consistently lower in group-1 calves from 4 weeks to end of the study. Plasma pepsinogen and serum gastrin concentrations also increased significantly (P < 0.05) in both groups that received inoculations. We concluded that decreased plasma insulin concentrations are contributory to changes in postabsorptive protein metabolism, and that serum gastrin concentrations are more representative of the pathologic changes in the abomasum than are plasma pepsinogen concentrations.


Clinical evaluation of the efficacy of inoculating cattle with a vaccine containing Tritrichomonas foetus. To test the efficacy of a polyvalent Tritrichomonas foetus vaccine, 130 nulliparous heifers were randomly assigned to either receive the test T foetus vaccine or to serve as nonvaccinated controls. The polyvalent test vaccine consisted of a Campylobacter fetus/Leptospira canicola-grippotyphosa-hardjo-icterohaemorrhagiae-pamona bacterine containing 5 x 10(7) killed T foetus/dose. The polyvalent control vaccine consisted of the aforementioned formulation without T foetus. Heifers were administered 2 doses of control or experimental vaccine at 3-week intervals. Heifers were bred to T foetus-infected bulls and their conception and pregnancy rates were determined throughout gestation. In addition, serum samples were analyzed to determine induced concentrations of antitrichomonal antibodies and vaginal secretions were sampled to determine T foetus infection rates in control and vaccinated animals. One week after each of the 15-day breeding periods, 60% (6 of 10) of tested vaccinates and 80% (8 of 10) of tested control animals were T foetus culture-positive. The mean duration of infection of vaccinates was 3.8 weeks (+/- 7.5 days), compared with 5.4 weeks (+/- 7.5 days) of infection for control heifers. All vaccinates developed increased immunofluorescence and serum neutralizing antibody titers following the first immunization, and had additional increases of at least fourfold in response to the second injection. In contrast, no consistent increase in immunofluorescence or serum neutralizing antibodies was observed in control animals. Conception rates were 89.2% for vaccinates and 85.9% for control animals 30 days after breeding and 80 to 90% of these remained pregnant 60 days after breeding.(ABSTRACT TRUNCATED AT 250 WORDS)


Evaluation of two test procedures for diagnosis of giardiasis in dogs. Two commercially available tests, an antigen-capture ELISA for use on fecal samples, and a peroral nylon string test for use in dogs, were compared with a zinc sulfate fecal concentration technique (ZSCT) for detection of giardiasis in dogs. Of 77 dogs and 164 fecal samples (from these dogs), 33 and 52, respectively were found to be Giardia-positive on the basis of results of the ZSCT. The ELISA gave false-negative results for 10 and 14% of ZSCT-positive dogs and fecal samples, respectively, and false-positive results (relative to the ZSCT test results) in 13 and 10% of ZSCT-positive dogs and fecal samples, respectively. Of the 18 string-tested dogs, 14 were positive by results of the ZSCT. Of the 4 dogs that were Giardia-negative by ZSCT, 2 were Giardia-positive by ELISA. Dogs were sedated and given water and metoclopramide to aid passage into the duodenum of the capsule containing a nylon string. Of the 21 string tests performed on the 18 dogs, only 5 strings reached the duodenum, and 0 of the 5 yielded positive results for Giardia sp. Because the string broke in 1 dog (leaving most in the gastrointestinal tract and, therefore, producing a risk of string foreign body) further string tests were not done.


Acute toxicity of paraherquamide and its potential as an anthelmintic. Paraherquamide, an oxindole alkaloid metabolite of Penicillium paraherquei and P charlesii, is a new anthelmintic with potential broad-spectrum use. In initial trials, it had an excellent safety profile in cattle and sheep at doses efficacious against a dozen or more helminths, but recently it produced unexpected and severe toxicosis in dogs at doses far below those that were safe in the ruminants. To provide data on which to build rational safety tests in the future, we tested the acute toxicity of paraherquamide administered PO to male CD-1 mice and compared its profile with the most potent anthelmintic known, ivermectin. The estimated doses lethal to 50% of a group of mice were 14.9 and 29.5 mg/kg of body weight for paraherquamide and ivermectin, respectively. The no-effect doses were 5.6 and 18.0 mg/kg for paraherquamide and ivermectin, respectively. Signs of intoxication in paraherquamide-treated mice, if they developed, emanated within 30 minutes of administration, irrespective of dose, and consisted of either mild depression with complete recovery or a 5- to 10-minute period of breathing difficulty followed by respiratory failure and death by 1 hour after treatment. Gross necropsy findings in paraherquamide-treated mice that died in the high-dose group were normal. Ivermectin-related toxicity was slower and more predictable, taking place over a 3-day period, with dose-dependent signs of intoxication consisting of tremors, ataxia, recumbency, coma, and death. Necropsy of ivermectin-treated mice that died in the high-dose group revealed dehydration, a condition most likely resulting from the coma-induced state.(ABSTRACT TRUNCATED AT 250 WORDS)


Induction of fatty liver in cows by ethionine administration and concomitant decreases of serum apolipoproteins B-100 and A-I concentrations. Ethionine, an analogue of methionine, induces fatty liver in rats by inhibiting protein synthesis, including that of apolipoproteins in liver. Ethionine was administered to cows to elucidate the participation in fatty liver development of impaired triglyceride secretion from liver attributable to decreased apolipoprotein synthesis. The administration resulted in a significant increase of liver triglyceride contents. Several apolipoproteins were found to have decreased concentrations. In particular, apolipoprotein B-100 in very low-density (0.95 to 1.006 g/ml) lipoprotein and in low-density (1.006 to 1.063 g/ml) lipoprotein fractions was greatly reduced. The decreases of apolipoprotein B-100 concentrations in the 2 lipoprotein fractions were at least partly correlated to the decreased triglyceride concentrations in the respective fractions. Decreased concentrations of apolipoprotein A-I in high-density (1.063 to 1.210 g/ml) lipoprotein were also observed, although not as distinctly as with apolipoprotein B-100. Total cholesterol and phospholipid concentrations in low- and high-density lipoprotein fractions were decreased. The decrease in cholesterol was attributed to reduced concentrations of cholesteryl esters. It was suggested that the impaired lipid secretion from liver attributable to the decreased apolipoprotein concentrations has a role in ethionine-induced fatty liver of cows.


Effects of furosemide and pentoxifylline on blood flow properties in horses. The effects of furosemide and pentoxifylline on blood flow properties in horses were investigated. Hematologic and rheologic changes were examined in 4 horses before and 3 minutes after administration of epinephrine (1 mg, IV). The next day, hemorheologic changes were determined before and 3 hours after administration of furosemide (1 mg/kg of body weight, IM), and after administration of epinephrine at the sampling at 3 hours. Hematologic and rheologic changes were evaluated weekly in 3 horses given pentoxifylline (8.5 mg/kg, q 12 h, PO) for 28 days. In addition, hemorheologic responses to epinephrine were determined on days 0, 14, and 28 of pentoxifylline treatment. Neutrophil filtration studies were also performed 2 hours after IV administration of pentoxifylline (8.5 mg/kg). Postepinephrine values for PCV, RBC and WBC counts, and blood viscosity were greater than preepinephrine values. Erythrocyte sedimentation rates decreased after epinephrine, whereas RBC filterability did not change. Treatment with furosemide was associated with increases in mean RBC hemoglobin concentration and blood viscosity. Filterability of RBC did not change. Treatment with pentoxifyllie resulted in an increase in RBC filterability and erythrocyte sedimentation rate and a decrease in PCV; however, mean values for hematocrit and RBC count did not change. Treatment with pentoxifylline did not result in a change in resting blood viscosity, but markedly reduced the postepinephrine increase in blood viscosity. Neither IV nor orally administered pentoxifylline had an effect on neutrophil filtration. It was concluded that pentoxifylline has beneficial effects on RBC filterability and postepinephrine changes in blood viscosity, which may contribute to improvements of microcirculatory blood flow. In addition, furosemide may exacerbate exercise-associated hyperviscosity in horses.


Composition and analysis of cerebrospinal fluid in clinically normal adult cattle. Cerebrospinal fluid and serum were obtained from 16 clinically normal adult cows (11 dairy, 5 beef). Sodium, potassium, magnesium, total protein, and albumin concentrations, osmolality, and lactate dehydrogenase and creatine kinase activities, were quantified in CSF and serum. Total and differential cell counting, protein electrophoresis, and IgG quantification were performed on CSF. Statistical analyses of these variables, including mean, SEM, range, and 95% confidence intervals, were performed. Effects of blood contamination were evaluated, and were found to be negligible for all measured constituents. Correction factors for CSF creatine kinase and lactate dehydrogenase activities accounting for cellular contamination were developed. Total nucleated cell count was similar to counts in CSF of other species, but higher than values in healthy people. Differential leukocyte count in CSF was similar to that reported in CSF of other domestic animals: mostly lymphocytes, fewer monocytoid cells, and scant neutrophils. Cerebrospinal fluid protein concentration was higher than concentration reported for dogs, goats, and people, but was similar to values reported for horses. Beef cows had higher CSF total protein concentration than did dairy cows; also, beef cows had higher CSF gamma-globulin concentration. The concentration of sodium in CSF was slightly higher than the value in serum, and potassium concentration was lower than the value in serum. In contrast to studies of human beings, CSF osmolality was generally less than serum osmolality in the cows studied. Reference values for CSF electrolyte concentrations and osmolality are useful for diagnosis of salt poisoning and for assessment of the effects of fluid therapy. Magnesium concentration was lower in CSF, compared with serum.(ABSTRACT TRUNCATED AT 250 WORDS)


Platelet aggregation in dogs after sedation with acepromazine and atropine and during subsequent general anesthesia and surgery. Platelet aggregation and adenosine triphosphate (ATP) release were measured by use of the impedance method in blood samples obtained from 25 adult female Beagles before and after sedation with acepromazine (0.13 mg/kg of body weight) and atropine (0.05 mg/kg), and during general anesthesia. General anesthesia was induced by IV administration of thiamylal (average dosage, 2.1 mg/kg; range, 1.2 to 4.2 mg/kg) and was maintained with halothane in oxygen. Samples of jugular venous blood were obtained from each dog, using citrate as anticoagulant. Platelet count was done on each sample. Platelet aggregation and ATP released from the aggregating platelets were measured within 2.5 hours of sample collection, using a whole-blood aggregometer. Adenosine diphosphate (ADP) or collagen was used as aggregating agent. For each aggregating agent, platelet aggregation and ATP release were measured over 6 minutes. After sedation with acepromazine and atropine, significant (P < 0.01) reduction was observed in platelet count (from median values of 341,000 cells/microliters to 283,000 cells/microliters) and in the ability of platelets to aggregate in response to ADP (from 14.0 to 7.0 omega). During the same period, maximal release of ATP in response to collagen also was reduced (from 5.56 mumol to 4.57 mumol; P < 0.01); however, this difference ceased to be significant when ATP release was normalized for platelet count. During general anesthesia and surgery (200 minutes after sedation), platelet count and aggregation responses to ADP and collagen had returned to presedation values. None of the dogs in this study appeared to have hemostasis problems during surgery.(ABSTRACT TRUNCATED AT 250 WORDS)


Effect of treatment with erythromycin and rifampin during the acute stages of experimentally induced equine ehrlichial colitis in ponies. Sixteen healthy ponies were inoculated IV with Ehrlichia risticii-infected P388D1 mouse monocytes. Of the 16 ponies, 15 developed clinical signs of equine ehrlichial colitis. Twenty-four hours after onset of fever (rectal temperature > 38.8 C), 7 ponies were treated with 25 mg of erythromycin stearate/kg of body weight and 10 mg of rifampin/kg, given orally every 12 hours for 5 days. The remaining 8 ill ponies served as nontreated controls. All ponies were observed for progression of clinical signs typical of equine ehrlichial colitis. Within 12 hours of initiation of treatment, 4 of the 7 treated ponies had rectal temperature < 38.4 C and, within 24 hours, 6 of the 7 ponies had rectal temperature < 38.3C. In contrast, all control ponies had rectal temperature > 39.2 C at 24 hours (P < 0.05). Of the 7 treated ponies, 4 no longer had signs of mental depression after the second day of treatment, and only 1 of the 7 ponies had mild signs of depression after the third day of treatment. In contrast, control ponies had high mental depression score during the observation period (P < 0.05). Feed intake improved in ponies of the treatment group, with feed intake of 4 of the 7 ponies returning to normal; the other 3 ponies were only mildly anorectic by the second day of treatment. Control ponies progressively decreased their feed intake during the observation period (P < 0.05). One control pony and 2 treated ponies developed diarrhea before the treatment/observation period began. Only 1 treated pony developed diarrhea after treatment began. Of the 8 control ponies, 7 developed diarrhea.(ABSTRACT TRUNCATED AT 250 WORDS)


Effects of three antiarthritic drugs on fibronectin and keratan sulfate synthesis by cultured canine articular cartilage chondrocytes. Because articular chondrocytes are a target for drugs that can influence the integrity of cartilage, we investigated the effects of 3 antiarthritic drugs, glycosaminoglycan polysulfate, diclofenac-Na, and S-adenosylmethionine sulfate p-toluenesulfonate on total protein, fibronectin, and DNA synthesis, as well as on extradomain-A fibronectin and keratan sulfate content. Glycosaminoglycan polysulfate stimulated dose-dependent incorporation of [35S]methionine into protein and fibronectin, whereas incorporation of [3H]thymidine into DNA was unaffected. Total fibronectin, extradomain-A fibronectin, and keratan sulfate content were high in chondrocyte cultures treated with glycosaminoglycan polysulfate. In contrast, fibronectin and DNA synthesis, as well as extradomain-A fibronectin and keratan sulfate content were unaffected by diclofenac-Na. S-Adenosyl-methionine decreased dose-dependently the synthesis of fibronectin, as well as the content of fibronectin and keratan sulfate. At the highest concentration of S-adenosyl-methionine tested, findings suggest that cell viability was impaired as assessed by the release of lactate dehydrogenase into the media.


Pharmacokinetics of norfloxacin and its N-desethyl- and oxo-metabolites in broiler chickens. Norfloxacin was given to 2 groups of chickens (8 chickens/group) at a dosage of 8 mg/kg of body weight, IV and orally. For 24 hours, plasma concentration was monitored serially after each administration. Another group of chickens (n = 30) was given 8 mg of norfloxacin/kg orally every 24 hours for 4 days, and plasma and tissue concentrations of norfloxacin and its major metabolites desethylenenorfloxacin and oxonorfloxacin were determined serially after the last administration of the drug. Plasma and tissue concentrations of norfloxacin, desethylenenorfloxacin, and oxonorfloxacin were measured by use of high-performance liquid chromatography. Pharmacokinetic variables were calculated, using a 2-compartment open model. For norfloxacin, the elimination half-life (t1/2 beta) and the mean +/- SEM residence time for plasma were 12.8 +/- 0.59 and 15.05 +/- 0.81 hours, respectively, after oral administration and 8.0 +/- 0.3 and 8.71 +/- 0.23 hours, respectively, after IV administration. After single oral administration, norfloxacin was absorbed rapidly, with Tmax of 0.22 +/- 0.02 hour. Maximal plasma concentration was 2.89 +/- 0.20 microgram/ml. Oral bioavailability of norfloxacin was found to be 57.0 +/- 2.4%. In chickens, norfloxacin was mainly converted to desethylenenorfloxacin and oxonorfloxacin. Norfloxacin parent drug and its 2 major metabolites were widely distributed in tissues. Considerable tissue concentrations of norfloxacin, desethylenenorfloxacin, and oxonorfloxacin were found when norfloxacin was administered orally (8 mg/kg on 4 successive days). The concentration of the parent fluoroquinolone in fat, kidneys, and liver was 0.05 micrograms/g on day 12 after the end of dosing.


Ultrasonographic and quantitative histologic assessment of sequelae to testicular biopsy in stallions. A sample of testicular parenchymal tissue, approximately 2 x 7 x 7 mm, was aseptically removed from 1 testis in each of 9 stallions on day 0. Slight to moderate hemorrhage from the tunica albuginea was observed in 8 stallions, but bleeding from the parenchyma was detected in only 2 stallions. Stallions were castrated 27 days later. Normal development of granulation tissue was evident at the biopsy site, but hematomas were not observed. In situ measurement of the widths of the right and left testes, total scrotal width, and evaluation of testicular echogenicity during ultrasonography were variables used to monitor changes in the testicular parenchyma from 14 days before biopsy through 27 days after biopsy. The control testis was consistently larger than the biopsied testis, except for day 3. Ultrasonography revealed signs of a localized change in the parenchyma of the biopsied testis in 4 stallions, but each lesion decreased in size by day 27. Tissues removed during biopsy enabled an excellent appraisal of spermatogenesis at that time. Detailed examinations of seminiferous tubules in the testes were performed to assess for damage to testicular function. At castration, samples were taken from 6 sites in each testis. Quantitative histologic evaluations of testicular tissues revealed low numbers of spherical spermatids and pachytene spermatocytes in biopsied testes, compared with control testes. It was concluded that there was a transitory increase in degeneration of preleptotene spermatocytes and B spermatogonia at the time of biopsy. A mild inflammatory response at the biopsy site in some testes was evidenced by an increased number of leukocytes at the biopsy site and at a dorsal site.(ABSTRACT TRUNCATED AT 250 WORDS)


Development of enzyme-linked immunosorbent assays for conglutinin, mannan-binding protein, and serum amyloid-P component in bovine sera. Sandwich ELISA were developed to quantitatively determine conglutinin (CG), mannan-binding protein (MBP), and serum amyloid-P component (SAP) in the sera of cattle. The ELISA system was found to have high repeatability for quantitation of these serum proteins at concentration as low as 5 ng/ml. From results obtained for 10 healthy cows aged 2 to 7 years, mean +/- SD serum concentrations were 56.5 +/- 14.4 micrograms of CG/ml, 2.37 +/- 0.87 micrograms of MBP/ml, and 11.14 +/- 3.92 micrograms of SAP/ml, respectively. Values in 6 healthy heifer calves aged 6 months were 3.45 +/- 1.22 micrograms/ml for CG, 1.71 +/- 0.96 micrograms/ml for MBP, and 5.45 +/- 2.75 micrograms/ml for SAP, respectively. Concentrations in 9 healthy bullocks aged 6 months were 1.83 +/- 0.66 micrograms/ml for CG, 1.04 +/- 0.63 micrograms/ml for MBP, and 4.9 +/- 1.13 micrograms/ml for SAP, respectively.


Effect of titanium endoprostheses on bone mineral density measurements, using quantitative computed tomography. Quantitative computed tomography has been used extensively to measure bone mineral density; particularly in the vertebral column and in the proximal portion of the femur in human beings with osteoporosis. Other potential applications of this technique include evaluation of bone adjacent to metallic endoprostheses and evaluation of fractures as they heal. Unfortunately, metal causes severe image degradation, principally seen as starburst streaking. One method used to decrease these artifacts is by imaging less-attenuating materials, such as titanium alloy. Titanium decreases image degradation sufficiently to allow accurate determination of the geometric properties of cadaveric bone. In our study, the effect of a titanium segmental endoprosthesis on bone mineral density measurement was determined by use of bone specimens from dogs and calibration standards. Titanium decreased the bone mineral density of calibration solutions from 6.8 (500 mg/cm3) to 17.7% (250 mg/cm3), and increased bone mineral density of cortical bone by 5.3%. Titanium did not affect the repeatability of these scans, indicating that the error caused by titanium was systematic and can be corrected. Our data were suggestive that quantitative computed tomography can be used to measure bone mineral density of cortical bone adjacent to titanium endoprostheses, with a predictable increase in density measurement.


Effects of monensin on selenium status and related factors in genetically hypo- and hyperselenemic growing swine. Monensin is an ionophoretic antibiotic, which selectively transports alkali metal cations across biological membranes. In growing swine, monensin toxicosis causes acute, degenerative cardiac and skeletal myopathy resembling vitamin E-selenium deficiency. Selenium is an essential trace element incorporated in glutathione peroxidase (GSH-Px), an antioxidant enzyme system that protects subcellular membranes. In our study, we examined the effects of monensin on body weight, Se balance, antioxidant status, and serum concentrations of selected minerals in growing pigs that were genetically hypo- or hyperselenemic (hypo-Se and hyper-Se, respectively). Three groups of eight 8-week-old pigs, each comprised of 4 hypo-Se and 4 hyper-Se pigs (76.4 +/- 3.0 and 106.3 +/- 10.3 ng of Se/ml of serum, respectively), were fed standard diets containing 0.1 mg of supplemental Se/kg of body weight, and either 0, 200, or 400 mg of monensin/kg for a 77-day period, followed by a 28-day monensin withdrawal period. On days 0, 7, 28, 56, 70, and 98, all pigs were weighed and blood was collected for determination of serum GSH-Px, creatine phosphokinase, and aspartate transaminase values, as well as serum concentrations of vitamin E, Se, Ca, Cu, Fe, K, Mg, Na, P, and Zn. Significance of main effects of monensin treatment, genetic Se status, and their interactions was tested by Fisher's variance ratio test, followed by conditional comparison of treatment means with a Bonferroni test. Signs of monensin toxicosis were not observed and monensin consumption had no effect on body weight, or serum creatine phosphokinase, aspartate transaminase, or Se values. However, pigs consuming monensin had consistently higher serum GSH-Px activities, possibly because of increased synthesis of this adaptive antioxidant enzyme. Interactions were not found between monensin and genetic Se status. Hyperselenemic pigs were heavier and had higher serum Se and GSH-Px values than hypo-Se pigs. Furthermore, hypo-Se and hyper-Se pigs were hypo- and hypercupremic, respectively, suggesting genetic regulation of copper status. It is likely that pigs with inadequate antioxidant status (hyposelenemia, hypocupremia) are more susceptible to diseases associated with cellular membrane damage, such as vitamin E-Se deficiency disease and monensin toxicosis.


Diet and exercise as potential risk factors for osteochondritis dissecans in dogs. A matched case-control study was conducted to evaluate dietary components and exercise patterns as potential risk factors for osteochondritis dissecans in dogs. A telephone interview, with a standard questionnaire and protocol, was used to collect data on dietary intake of calories and nutrients and on the usual amounts and types of exercise of each dog. Thirty-one dogs with osteochondritis dissecans and 60 controls were matched on the basis of breed, sex, and age. Using a conditional logistic regression model, high dietary calcium, playing with other dogs, and drinking well water (rather than city water) were associated with increased risk of osteochondritis dissecans. Feeding of specialty dry dog foods was associated with decreased risk.


Effect of dietary phosphoric acid supplementation on acid-base balance and mineral and bone metabolism in adult cats. Experimental evidence indicates that maintenance of urinary pH < or = 6.4 is the single most effective means of preventing feline struvite crystalluria or urolithiasis of noninfectious causes. This may be accomplished by dietary acidification, but must be moderated to avoid potential adverse effects of excessive acidification, including bone demineralization, negative calcium balance, potassium depletion, and renal disease. Effects of chronic dietary phosphoric acid supplementation on acid-base balance and on mineral and bone metabolism were investigated in adult, domestic cats. One group of 6 cats was fed a basal, naturally acidifying diet without added acidifiers, and another group of 6 cats was fed 1.7% dietary phosphoric acid. Changes observed during 12 months of study included development of noncompensated metabolic acidosis, increased urinary calcium excretion, and lower but positive calcium balance in cats of both groups. Urinary pH decreased in cats of both groups, but was significantly (P < 0.05) and consistently maintained < or = 6.4 in cats given dietary phosphoric acid. Urinary phosphorus excretion increased in cats of both groups, but was significantly (P < 0.05) greater in phosphoric acid-supplemented cats, leading to lower overall phosphorus balance as well. Potassium balance decreased in cats of both groups, but was only transiently negative in the phosphoric acid-supplemented cats midway through the study, and normalized at positive values thereafter. Plasma taurine concentration was not affected by dietary acidification, and remained well within the acceptable reference range for taurine metabolism. Double labeling of bone in vivo with fluorescent markers was followed by bone biopsy and histomorphometric measurement of several static and dynamic variables of bone formation. Overall indices of bone formation decreased in cats of both groups with age and confinement, but were not affected by dietary phosphoric acid supplementation. Dietary supplementation with phosphoric acid used as the principal inorganic P source to achieve moderate and stable degree of urinary acidification, did not appear over the course of 1 year, to have induced adverse effects on mineral, bone, or taurine balance in these adult domestic cats.


Biomechanical comparison of three internal fixations for treatment of slipped capital femoral epiphysis in immature dogs. The biomechanical strength and stiffness of 3 fixation techniques used to repair acute slipped capital femoral epiphysis were evaluated in bone specimens from immature dogs. A servohydraulic testing machine was used to create slipped capital femoral epiphysis in 9 pairs of femurs by shearing the capital femoral epiphysis along the physis in a craniocaudal direction. The slip was reduced and repaired with 1, 2, or 3 double-pointed, 1.6-mm (0.062-inch) smooth pin(s) and retested. The strength and stiffness of each intact femur (which served as the control) and repaired femur were compared. Results of the study indicated that differences among the failure strengths of 1- and 2-pin fixations and their respective controls were not significant; however, the 3-pin fixation was 29% stronger than its control and was 60 and 45% stronger than the 1- and 2-pin fixations, respectively. One- and 2-pin fixations were 34 and 24% less stiff than their respective controls, whereas the stiffness of the 3-pin fixation was similar to its control. The 2- and 3-pin fixations were 48 and 76% stiffer, respectively, than the 1-pin fixation, but were not significantly different, compared with each other.


Functional, radiographic, and histologic assessment of healing of autogenous osteochondral grafts and full-thickness cartilage defects in the talus of dogs. A circular (5.5 mm diameter) full-thickness cartilage defect was created on the medial ridge of the talus in 12 skeletally mature dogs. In 6 dogs, the articular surface of the lesion was repaired, using an osteochondral graft obtained from the ipsilateral manus. The graft (digit I, first phalanx, distal articular surface and diaphysis) was contoured to obtain a press fit in the drilled talar recipient site. In 6 dogs, the lesion was not treated and healed by fibrous tissue replacement. Functional assessment (lameness, hock range of motion, joint stability, joint crepitus, and mid-femoral muscle circumference) was completed before surgery and at postoperative weeks 2 through 20. Radiographic assessment (periarticular soft tissue width, joint space width, osteophyte formation, and graft incorporation) was completed before surgery and at postoperative weeks 0, 6, 12, and 20. To facilitate histologic assessment, tissues were stained with toluidine blue and H&E. Histologic assessment of the articular surface on the surgically treated talus, ipsilateral tibia, and contralateral talus was completed, using a modification of the Mankin grading system. Subchondral bone was examined to assess graft viability and incorporation. Analysis of the ordinal data was completed, using a Mann-Whitney rank sum test. All dogs were fully weight bearing by postoperative week 7. Dogs without grafts had significantly (P = 0.036) better clinical function at postoperative week 6. Significant difference in functional assessment was not evident at postoperative week 20. Immediate postoperative radiographic assessment revealed significant (P = 0.005) difference between nongrafted and grafted groups. Significant difference was not observed at postoperative week 6, 12, or 20. All grafts appeared radiographically incorporated by postoperative week 12. All grafts restored joint surface congruity, whereas 3 of 6 nongrafted lesions had poor articular congruity. Of 6 grafts, 4 partially retained normal hyaline cartilage, resulting in significantly (P = 0.014) lower Mankin grades. Significant histologic differences between groups were not apparent when the apposing tibia and control talus were examined. Talar reconstruction by use of a phalangeal osteochondral graft is a viable surgical procedure. These data indicate that normal articular and subchondral architecture are more closely approximated by osteochondral reconstruction than by fibrous tissue repair.


Evaluation of intestinal villus height in rats after ischemia and reperfusion by administration of superoxide dismutase, polyethylene glycol-conjugated superoxide dismutase, and two 21-aminosteroids. Intestinal ischemia was induced and maintained for 60 minutes in male Sprague-Dawley rats weighing 175 to 225 g. Prior to reperfusion, the following drugs were administered via the caudal vena cava: 0.9% NaCl (0.5 ml), superoxide dismutase (SOD; 1,000 IU/kg of body weight), polyethylene glycol-conjugated SOD (PEG-SOD; 1,000 IU/kg), or the 21-aminosteroids, U74006F (3 mg/kg) or U78715G (3 mg/kg). A sham-operated control group was included. Animals from each group were euthanatized at 5 periods of reperfusion: 5 minutes, 30 minutes, 18 hours, 3 days, and 7 days after reperfusion. Fixed tissues were embedded in paraffin, sectioned at 5 microns, and stained with H&E. Villi profiled in cross section were measured from the crypt villus junction to the tip of the villus. The mean villus height for each rat was calculated and compared by two-way ANOVA to determine the effects of time and treatment. Villus height was maintained after 30 minutes of reperfusion in rats of the sham- and U74006F-treated groups; U78715G and SOD treatment attenuated the loss in villus height, and villus height was not maintained in the PEG-SOD- and 0.9% NaCl-treated rats. In all rats, villus height was comparable to, or was greater than villus height in sham-operated controls by 18 hours after reperfusion in all animals and remained constant through 7 days. Administration of the 21-aminosteroids maintained villus height after ischemia and reperfusion. Treatment with PEG-SOD did not maintain villus height to the degree observed in rats treated with SOD.


Effect of various vaccination procedures on shedding, latency, and reactivation of attenuated and virulent pseudorabies virus in swine. Various procedures of vaccination for pseudorabies were compared for their effects on shedding, latency, and reactivation of attenuated and virulent pseudorabies virus. The study included 6 groups: group 1 (10 swine neither vaccinated nor challenge-exposed), group 2 (20 swine not vaccinated, but challenge-exposed), and groups 3 through 6 (10 swine/group, all vaccinated and challenge-exposed). Swine were vaccinated with killed virus IM (group 3) or intranasally (group 4), or with live virus IM (group 5) or intranasally (group 6). The chronologic order of treatments was as follows: vaccination (week 0), challenge of immunity by oronasal exposure to virulent virus (week 4), biopsy of tonsillar tissue (week 12), treatment with dexamethasone in an attempt to reactivate latent virus (week 15), and necropsy (week 21). Vaccination IM with killed or live virus and vaccination intranasally with live virus mitigated clinical signs and markedly reduced the magnitude and duration of virus shedding after challenge exposure. Abatement of signs and shedding was most pronounced for swine that had been vaccinated intranasally with live virus. All swine, except 4 from group 2 and 1 from group 4, survived challenge exposure. Only vaccination intranasally with live virus was effective in reducing the magnitude and duration of virus shedding after virus reactivation. Vaccination intranasally with killed virus was without measurable effect on immunity. Of the 55 swine that survived challenge exposure, 54 were shown subsequently to have latent infections by use of dexamethasone-induced virus reactivation, and 53 were shown to have latent infections by use of polymerase chain reaction (PCR) with trigeminal ganglia specimens collected at necropsy. Fewer swine were identified by PCR as having latent infections when other tissues were examined; 20 were identified by testing specimens of olfactory bulbs, 4 by testing tonsil specimens collected at necropsy, and 4 by testing tonsillar biopsy specimens. Eighteen of the 20 specimens of olfactory bulbs and 3 of the 4 tonsil specimens collected at necropsy in which virus was detected by PCR were from swine without detectable virus-neutralizing antibody at the time of challenge exposure. One pig that had been vaccinated intranasally with live virus shed vaccine virus from the nose and virulent virus from the pharynx concurrently after dexamethasone treatment. Evaluation of both viral populations for unique strain characteristics failed to provide evidence of virus recombination.


Arterial-venous difference in atrial natriuretic peptide concentration during exercise in horses. Six nontrained mares were subjected to steady-state, submaximal treadmill exercise to examine the effect of exercise on the plasma concentration of atrial natriuretic peptide (ANP) in arterial, compared with mixed venous, blood. Horses ran on a treadmill up a 6 degree grade for 20 minutes at a speed calculated to require a power equivalent to 80% of maximal oxygen uptake (VO2MAX). Arterial and mixed venous blood samples were collected simultaneously from the carotid and pulmonary arteries of horses at rest and at 10 and 20 minutes of exercise. Plasma was stored at -80 C and was later thawed; ANP was extracted, and its concentration was determined by radioimmunoassay. Exercise caused significant (P < 0.05) increases in arterial and venous plasma ANP concentrations. Mean +/- SEM arterial ANP concentration increased from 25.2 +/- 4.4 pg/ml at rest to 52.7 +/- 5.2 pg/ml at 10 minutes of exercise and 62.5 +/- 5.2 pg/ml at 20 minutes of exercise. Mean venous ANP concentration increased from 24.8 +/- 4.3 pg/ml at rest to 67.2 +/- 14.5 pg/ml at 10 minutes of exercise and 65.3 +/- 13.5 pg/ml at 20 minutes of exercise. Significant differences were not evident between arterial or mixed venous ANP concentration at rest or during exercise, indicating that ANP either is not metabolized in the lungs or is released from the left atrium at a rate matching that of pulmonary metabolism.


Cardiopulmonary effects of etomidate in hypovolemic dogs. Cardiopulmonary effects of etomidate administration were studied in hypovolemic dogs. Baseline cardiopulmonary data were recorded from conscious dogs after instrumentation. Hypovolemia was induced by withdrawal of blood from dogs until mean arterial pressure of 60 mm of Hg was achieved. Blood pressure was maintained at 60 mm of Hg for 1 hour, by further removal or replacement of blood. One milligram of etomidate/kg of body weight was then administered IV to 7 dogs, and the cardiopulmonary effects were measured 3, 15, 30, and 60 minutes later. After blood withdrawal and prior to etomidate administration, heart rate, arterial oxygen tension, and oxygen utilization ratio increased. Compared with baseline values, the following variables were decreased: mean arterial pressure, mean pulmonary arterial pressure, central venous pressure, pulmonary wedge pressure, cardiac index, oxygen delivery, mixed venous oxygen tension, mixed venous oxygen content, and arterial carbon dioxide tension. Three minutes after etomidate administration, central venous pressure, mixed venous and arterial carbon dioxide tension, and venous admixture increased, and heart rate, arterial and venous pH, and arterial oxygen tension decreased, compared with values measured immediately prior to etomidate administration. Fifteen minutes after etomidate injection, arterial pH and heart rate remained decreased. At 30 minutes, only heart rate was decreased, and at 60 minutes, mean arterial pressure was increased, compared with values measured before etomidate administration. Results of this study indicate that etomidate induces minimal changes in cardiopulmonary function when administered to hypovolemic dogs.


Anatomy of the prepubic tendon in the horse, cow, sheep, goat, and dog. Analyses of the fibers in the prepubic tendon of the horse and ruminants have shown that it is composed of the crossed and uncrossed tendons of origin of the pectineus muscles, the pelvic tendons of the rectus and obliquus abdominis muscles, and the tendons of origin of the cranial parts of the gracilis muscles. Pelvic attachments of the linea alba and the yellow abdominal tunic are incorporated in it. It is not a transverse ligament, and it is not homologous to the human superior (cranial) pubic ligament. The dog differs in 4 respects: (1) the pectineus tendons do not cross, but each originates from the pubic bone of the same side; (2) an iliopubic cartilage is intercalated in the prepubic tendon on each side at the junction of the pectineus tendon and the abdominal and pelvic tendons of the external oblique at the caudal angle of the superficial inguinal ring; (3) in some dogs, the caudal border of the aponeurosis of the transversus abdominis joins the prepubic tendon; (4) the gracilis tendon does not extend to the prepubic tendon. The clinical anatomy was described, illustrated, and compared between species. Conflicting descriptions in the literature were discussed and resolved by new approaches to the dissection. Studies of the inguinal region in the cat and pig were reviewed. A table of nomenclature is included.


Estrogen and progesterone receptor status of mammary carcinomas and correlation with clinical outcome in dogs. Estrogen and progesterone receptors (ER, PR) were measured in cytosol fractions from 18 primary canine mammary carcinomas by use of biochemical assays. One or both receptors were detected (> 10 fmol/mg of cytosol protein) in 11 tumors: 5 ER and PR; 2 ER only; 4 PR only. Mean cytoplasmic receptor concentrations (fmol/mg of cytosol protein) were 22.8 +/- 2.9 (SEM) for ER and 51.0 +/- 10.3 for PR in tumors containing ER and PR, 28.8 +/- 12.1 for ER in tumors containing only ER and 13.2 +/- 1.5 for PR in tumors containing only PR. Estrogen or progesterone receptors or both were identified in 6 of 9 tubular adenocarcinomas, 4 of 5 papillary adenocarcinomas, and 1 of 1 squamous cell carcinoma. These receptors were not identified in solid carcinomas (n = 2) or a single spindle cell carcinoma. Although the number of cases was limited, survival times of dogs tended to be longest in those with tumors containing ER alone or in combination with PR, intermediate in those with tumors containing only PR, and shortest in those with tumors without ER or PR. A correlation was not apparent between receptor status and age, presence of ovaries, tumor size, or histologic classification of the tumor. In the analysis of this series, the extent of surgery (mastectomy of the involved gland vs unilateral or bilateral mastectomy) did not appear to influence the outcome of the disease, and metastasis to regional lymph nodes did not appear to be a reliable prognostic indicator.


Safety of ceftiofur sodium administered intramuscularly in horses. Ceftiofur sodium, a broad-spectrum cephalosporin antibiotic, was evaluated for safe use in horses. Male or female horses were allotted to groups and were given either saline solution (control), or 2.2, 6.6, or 11 mg of an aqueous solution of ceftiofur sodium/kg of body weight/d, IM, for 30 or 31 days. These dosages are expressed in terms of the ceftiofur free acid, and represent 1 to 5 times the proposed therapeutic dosage (2.2 mg/kg/d) administered for 3 times the maximal recommended duration of 10 days. Some of the horses were euthanatized and necropsied on day 31 or 32. The other horses were evaluated for an additional 30 days, and some were euthanatized and necropsied on day 60. The following types of data were collected: clinical observation; physical examination; pelleted food consumption; body weight; hematologic, serum biochemical, and urinalysis findings; organ weight; gross necropsy observations; and histopathologic findings. Ceftiofur sodium was generally well tolerated at the exaggerated doses and treatment durations used in these safety studies. Slight to mild decrease in pelleted food consumption was detected in horses given 6.6 or 11 mg of ceftiofur sodium/kg/d. Decreased food consumption began on day 2 and lasted for approximately 9 to 12 days. Generally, mild skeletal muscle irritation was detected by gross and microscopic examination of the injection sites of horses given ceftiofur sodium. Prevalence and severity of the muscle irritation tended to increase with increasing concentration of the dosing solution.(ABSTRACT TRUNCATED AT 250 WORDS)


The biomechanical efficacy of an oscillating K-wire driver. A new oscillating drill, designed for insertional ease and safety, was biomechanically tested using an MTS 812 servohydraulic material testing machine (Instrom). Holding strength and drilling force were compared against a traditional rotary drill using rabbit tibias to approximate the diameter and cortical thickness of human metacarpals. Three differently sized (0.028-, 0.045-, and 0.062-in. diameter) K-wires were evaluated for each drill. Mean peak axial load (drilling force) was significantly different for each wire driver type in each of the three sized K-wires (p < or = 0.01). The oscillating drill used an average of 3 N less force to penetrate either cortex. Mean peak pull-out force (holding strength) was higher for the oscillating drill, but the difference was not significant (p > or = 0.5). This study indicated that the oscillating drill required less force for insertion and had a similar holding strength as the rotary drill. In addition, our drill has been shown to be less damaging to surrounding soft tissues. This new type of drill is likely to be advantageous in the fields of hand, microsurgery, orthopedic, and plastic surgery, where bone fixation is often near vital neurovascular structures.


The epigastric fat transfer: an alternative free flap model in the rat. A free epigastric fat flap, a modification of the well-known cutaneous groin flap, is described in the rat. Vascular perfusion was successfully restored when transferred to the neck of the rat in 75% of the rats that underwent surgery, as assessed by multiple postoperative stripping tests and select microangiography. This flap offers the advantages of familiar anatomy, ease of postoperative care without risk of flap trauma, and a challenge to microsurgical technique development for successful flap transfer execution. Therefore, this free flap provides an additional animal model for use in microsurgical training as well as a research tool in fat transplantation physiology.


Hair removal by a depilatory does not affect survival in rodent experimental flaps. The current study looked at the effect of topically applied hair depilatory agent Nair on flap survival. In a 10 x 3-cm dorsal rat flap model, there were no statistically significant differences in survival noted on postoperative day 7 between control skin and flaps receiving 6 to 24 minutes of Nair preoperatively. Therefore, hair depilation by Nair can be used safely in this model.


Eminectomy for the treatment of chronic subluxation and recurrent dislocation of the temporomandibular joint and a new method of patient evaluation. We have performed this technique bilaterally on 39 patients with chronic subluxation and 13 patients with recurrent dislocation since 1985 and have had good results with patient satisfaction. These patients had significantly higher articular eminences than normal control individuals. Also, we have used echography as a new application of an old technique, to evaluate the patients objectively in the preoperative and postoperative periods.


Polyurethane-covered mammary implants: a 12-year experience. Polyurethane-covered mammary implants are the implants of choice in aesthetic and reconstructive mammary surgery. These implants give very good results in regard to breast contour and consistency, and have a very low complication rate. We present our 12-year experience using polyurethane-covered prostheses. We place the implant mostly in the subglandular or subcutaneous site, and their capsular contracture rate is extremely low (3.3%). Based on our experience, we also review the other complications and side effects occurring with polyurethane prostheses and discuss them in detail.


Laser deepithelialization of the transverse rectus abdominis musculocutaneous flap. Total or partial skin deepithelialization of the transverse rectus abdominis musculocutaneous (TRAM) flap is an integral component of this technique for achieving a successful breast reconstruction. In a manner similar to dermabrasion, the carbon dioxide laser in a defocused mode permits precise removal by vaporization of the epidermis and outer dermis. The extended application of this method for deepithelializing the TRAM flap is simple, rapid, and safe. Because a portion of the dermis always remains intact, another inherent advantage of this method is preservation of the subdermal vascular plexus that may be important for maintaining any precarious flap perfusion.


Continuous intraarterial infusion of prostaglandin E1 and heparin to extend and improve the survival of pedicled musculocutaneous flaps through unusual routes: a clinical preliminary report. Sixteen pedicled musculocutaneous flaps (pectoralis major, 3; latissimus dorsi, 4; and transverse rectus abdominis musculocutaneous [TRAM], 9) received continuous intraarterial infusion of prostaglandin E1 (5 micrograms/k of flap per day) and heparin (100 to 200 U/cannula per day) for 14 days postoperatively to extend the flap or improve survival in a high-risk patient. Therapy was successful in 15 patients. To preserve the main arterial inflow to the flap, the infusion was administered via the lateral thoracic artery in the pectoralis major and a branch to the serratus anterior muscle in latissimus dorsi flaps in retrograde fashion, respectively, and was via both the ipsilateral deep epigastric artery and the contralateral superficial epigastric artery in TRAM flaps. This technique permits the use of a pedicled flap in some patients who would otherwise require a free flap.


Reconstruction of the chest wall with e-PTFE following major resection. Nine patients underwent major chest wall resection at Thomas Jefferson University Hospital (Philadelphia, PA) over a 19-month period. Chest wall reconstruction was performed with an expanded polytetrafluoroethylene (e-PTFE) soft tissue patch (Gore-Tex) and vascularized flaps in all patients. The size of the skeletal defects ranged in area from 60 to 400 cm2. The primary indications for resection included chest wall sarcoma and radiation ulcer. Aggressive chest wall resection may be a patient's only opportunity for cure and an improved quality of life. In this series, chest wall resection was able to be performed with a low morbidity and no mortality. This study also demonstrates many of the advantages of e-PTFE as a chest wall substitute compared with other previously described prosthetic materials. The use of a Gore-Tex patch along with described flaps for soft tissue coverage provides good functional and aesthetic results.


Electrical nerve stimulation improves healing of diabetic ulcers. A controlled study of the effects of electrical nerve stimulation (ENS) was performed in conjunction with a standard treatment for healing chronic diabetic ulcers on 64 patients divided randomly into two groups. All patients received standard treatment (paste-impregnated bandage and a self-adhesive elastic bandage) plus placebo ENS or ENS (alternating constant current; frequency, 80 Hz; pulse width, 1 msec; intensity-evoking strong paresthesias) for 20 minutes twice daily for 12 weeks. Comparison of percentages of healed ulcer area and the number of healed ulcers was made after 2, 4, 6, 8, and 12 weeks. There were significant differences (p < 0.05) in both ulcer area and healed ulcers in the ENS group compared with the placebo group after 12 weeks of treatment. The results of the present study support the use of ENS in diabetic ulcers. ENS is easy to apply and can be used by the patient at home following instructions from a medical doctor or a therapist experienced in electrical stimulation and the treatment of ulcers. Additional studies are needed to identify the mechanisms involved in the promotion of ulcer healing with electrical stimulation and to determine the stimulus variables that most efficaciously accelerate tissue repair.


Pedicle scapular apophysis transplantation in congenital limb malformations. Congenital segmental amputations are difficult to correct. Free interposition bone grafts with growth centers were tried experimentally by many investigators even at the beginning of this century. Attempts at clinical application of this principle, however, were mostly failures. More recently, with the advent of microsurgical techniques, new hope has arisen. In particular, toe transfers in children have confirmed the survival of such growth centers, as these transfers could be found to grow normally [1]. The transfer of vascularized epiphysis with its growth plate has been shown in animal limbs to achieve a rate of growth comparable with the normal site. Originally, two donor sites were used with acceptable results in children. These were the superior epiphysis of the fibula and the iliac crest. So far, in most clinical applications, they have been used as appositional transfers. However, a growth problem occurring at the donor site has proved to be quite crippling.


Costs and complications in mandibular reconstruction. Because of increasing concerns about the high cost of complex medical care, we compared the combined cost of ablation and reconstruction incurred using five different management strategies for patients undergoing mandibular resection. We also compared the rates of complication and failure for the methods used. The records of 69 patients undergoing segmental or total mandibulectomy between January 1, 1986, and June 30, 1990, were reviewed. Of these, 15 had reconstruction with soft tissue only (average cost, $36,137; complication rate, 33%), whereas 20 had immediate reconstruction with vascularized bone (average cost, $46,894; complication rate, 50%), and 15 had reconstruction with only a metal plate (average cost, $47,678; complication rate, 73%). Nine patients had plate reconstructions initially but subsequently underwent reconstructions with bone (average cost, $54,346; complication rate, 78%), whereas 10 patients had no initial reconstruction but subsequently underwent delayed reconstruction with bone (average cost, $52,486; complication rate, 70%). If reconstruction was performed with bone, immediate reconstruction was more cost effective than delayed reconstruction and had a lower complication rate as well.