Effect of body position on the blood gases and ventilation volume of infants with chronic lung disease before and after feeding. [Effect of preterm infant position on weaning from mechanical ventilation]. Postural effects on pulmonary function and heart rate of preterm infants with lung disease. Effects of body position on blood gases and lung mechanics of infants with chronic lung disease during tube feeding. Lateral positioning of the stable ventilated very-low-birth-weight infant. Effect on transcutaneous oxygen and carbon dioxide. Decreased activity and oxygen desaturation in prone ventilated preterm infants during the first postnatal week. Pulmonary mechanics and gas exchange: effect of lateral positioning during recovery from respiratory distress syndrome. Randomized, controlled trial on tracheal colonization of ventilated infants: can gravity prevent ventilator-associated pneumonia? Postural effects on gas exchange in infants. Effects of position changes on transcutaneous carbon dioxide tension in neonates with respiratory distress.
The effect of body position before and after tube feeding was evaluated in six extremely immature infants who were being mechanically ventilated because of chronic lung disease. Their mean birthweight and gestational age were 722.7 g (range, 540 to 994) and 24.9 weeks (range, 23.9 to 26.0), respectively. This study was performed at a mean postnatal age of 47.5 days (range, 21 to 85 days). The prone position resulted in a significant increase in arterial oxygen saturation before and after feeding, whereas the tidal volume demonstrated an increase only before feeding. Also the prone position showed a significant decrease in heart rate before and after feeding and a tendency to decrease transcutaneous carbon dioxide tension values before feeding. There were no significant differences in minute ventilation despite increased tidal volume in the prone position, most likely due to a decrement of the spontaneous respiratory rate in the prone positioning. We conclude that the prone position may offer an advantage over the supine position in the management of extremely immature infants with chronic lung disease before and after feeding. To determine the effects of prone positioning on cardiorespiratory stability and weaning outcome of preterm infants during weaning from mechanical ventilation.
                From January to December 1999, a sample of 42 preterm infants, with birthweight < 2,000 g, mechanically ventilated in the first week of life, were randomly divided, in the beginning of the weaning process, into two groups according to the position: supine position (n = 21) or prone position (n = 21). Heart rate, respiratory rate, transcutaneous oxygen saturation and ventilatory parameters were recorded every one hour. Length of the weaning process and complications were also assessed.
                In both groups the mean gestational age was 29 weeks, most of the patients presented very low birthweight and respiratory distress syndrome. The mean length of the weaning process was 2 days. There were no differences between the groups regarding respiratory rate, heart rate and transcutaneous oxygen saturation, however, oxygen desaturation episodes were more frequent in supine position (p = 0.009). Ventilatory parameters decreased faster and reintubation was less frequent in the prone group (4% versus 33%). No adverse effects of prone positioning were observed.
                These results suggest that prone position is a safe and beneficial procedure during weaning from mechanical ventilation and may contribute to weaning success in preterm infants. nan The effects of body position and feeding on lung mechanics and blood gases in very low birthweight infants with chronic lung disease (CLD) is not fully elucidated.
                Seven very low birthweight infants who were being mechanically ventilated because of CLD were examined. They were enrolled in this study when their feeding volume exceeded 100 mL/kg per day. Each patient was kept on the same position (either prone or supine) during feeding. Feeding was given by a nasogastric tube for over 1 h every 3 h. Blood gases and lung mechanics were evaluated before, 20 min and 40 min after the initiation of the feeding and at the end of the feeding.
                The prone position resulted in a significant increase in arterial oxygen saturation during feeding. The tidal volume in the prone position was significantly larger than in the supine position only before feeding. There were no significant differences in minute ventilation between these positions during the study. Pulmonary resistance was not different in either position, but the static compliance and the work of breathing of spontaneous breaths were improved significantly when the infants were in the prone position. In the supine position, work of breathing increased and static compliance decreased significantly with time, while in the prone position, those values did not change significantly.
                The improvement in lung mechanics may partly explain better oxygenation obtained in the prone position. The prone position could decrease energy expenditure for spontaneous breathing and may shorten the period of ventilatory support for very low birthweight infants with CLD. Eighteen stable very-low-birth-weight (VLBW) mechanically ventilated infants with chronic lung disease were studied to examine the effects of right and left lateral positioning in contrast to supine positioning on transcutaneous (tc) oxygen (tcPO2) and carbon dioxide measurements (tcPCO2). The neonates were studied at a median postnatal age of 31 days (range, 17 to 57 days) and had median birth weights and gestational ages of 975 g (range, 570 to 1360 g) and 27.5 weeks (range, 24 to 30 weeks), respectively. Median fraction of inspiratory oxygen was 0.32 (range, 0.23 to 0.40). The sequence of study positions was randomly determined. Sleep state as well as tcPO2 and tcPCO2 were recorded every 30 s for five minutes. A significant difference in mean tcPO2 or tcPCO2 was not detected for any of the positions. Lateral positioning may facilitate the development of midline behavior in VLBW infants. Care givers are often reluctant to position infants in side lying, however, because of concerns that ventilation or oxygenation might be compromised. We conclude that placing the stable VLBW mechanically ventilated infant in a side-lying position has no deleterious effects on oxygenation and ventilation, as measured by tcPO2 and tcPCO2, and therefore should be encouraged. To compare the effects of supine and prone positions on oxygen saturation (SpO(2)), desaturation episodes (SpO(2) < 90% and >or= 20 seconds), and motor activity in ventilated preterm infants during their first postnatal week.
                With use of a crossover design, we randomly assigned infants to a supine/prone or prone/supine position sequence. Infants were placed in each position for 2 hours. A stabilization period of 10 minutes before observation of each position was allowed. During the protocol, care procedures were kept minimal and ventilator settings remained unchanged.
                Neonatal intensive care units at 2 tertiary care centers in Taiwan.
                The sample consisted of 28 infants receiving mechanical ventilation who were 25 to 36 weeks' gestation, without known congenital abnormalities, within 7 postnatal days of birth, and were not receiving sedation.
                When prone, infants had higher SpO(2), fewer episodes of oxygen desaturation, and less motor activity than when supine. No significant differences in duration of SpO(2) less than 90%, 85%, and 80% were found between the 2 positions. Seventy-four percent of desaturation episodes were associated with vigorous motor activity and crying.
                The prone position results in less motor activity and may stabilize oxygenation for ventilated preterm infants. This may conserve energy and decrease complications of hypoxia for sick preterm infants. Sixteen stable intubated premature infants without a clinically significant patent ductus arteriosus were studied during recovery from respiratory distress syndrome in order to determine the effects of left and right lateral, as compared to supine, positioning. Pulmonary mechanics were measured for spontaneous breaths 5 and 15 minutes after positioning, and arterial blood gases 15 minutes after positioning. Infants were randomized to 1 of 2 position sequences: (1) supine, left, supine, right or (2) supine, right, supine, left. No significant differences were detected between positions for dynamic compliance, tidal volume/kg, and total, inspiratory and expiratory pulmonary resistance. Likewise, no significant differences in PaO2 or PaCO2 were detected between the positions. The sequence of positions did not affect the pulmonary mechanics of spontaneous breaths or arterial blood gases. This suggest that short-term lateral positioning as well as supine positioning can be utilized without deleterious effects on pulmonary mechanics and gas exchange in neonates recovering from respiratory distress syndrome. The goal was to test the hypothesis that intubated infants positioned on their sides would be less likely to contract bacterial colonization in their tracheae, compared with those positioned supine.
                We conducted a prospective, randomized, controlled trial with 60 intubated infants; 30 infants were positioned supine (supine group), and 30 infants were maintained in the lateral position (lateral group). Tracheal aspirates were cultured and bacterial colony counts were recorded after 48 hours and after 5 days of mechanical ventilation.
                After 2 days, the numbers of positive tracheal cultures in the supine group (67%) and in the lateral group (47%) showed no statistical difference. After 5 days of mechanical ventilation, tracheal cultures differed significantly between groups. Cultures were positive for 26 infants (87%) in the supine group and 9 infants (30%) in the lateral group. Compared with the lateral group, more infants in the supine group experienced increased colony counts or had new organisms in their tracheal aspirates over time (21 vs 8 infants). The most common organisms isolated from tracheal aspirates in both groups were Gram-negative rods.
                Respiratory contamination is very common among ventilated infants. Therefore, judicious use of mechanical ventilation cannot be overemphasized. Gravitational force can ameliorate the onset of respiratory colonization. The mechanism and clinical applicability of such observations need to be explored further. In adults with unilateral lung disease, pulmonary gas exchange is better when the patients is positioned with the good lung dependent. We studied the effects of body position on gas exchange in 10 infants with unilateral lung disease by measuring transcutaneous oxygen and carbon dioxide pressures in the supine and right and left lateral positions. We also performed krypton lung scans and measured changes in thoracic gas volumes in four of the infants. Transcutaneous oxygen pressure (mean +/- S.E.) was greater with the good lung uppermost (82 +/- 7.6 mm Hg) than with the good lung dependent (73 +/- 7 mm Hg) (P less than 0.02) or in the supine position (78 +/- 7 mm Hg). There were no changes in transcutaneous carbon dioxide pressure. The proportion of ventilation to the good lung was greater with the good lung uppermost than with the good lung dependent (P less than 0.01) or in the supine position (P less than 0.02) (64 +/- 3, 46 +/- 6, and 59 +/- 7 per cent, respectively). There were no significant changes with position in functional residual capacity, tidal volume, or dynamic lung compliance. We conclude that oxygenation in infants with unilateral lung disease is best with the good lung uppermost--the reverse of what has been observed in adults. Routine neonatal care includes frequent position changes. Recent research has concluded that positions other than supine may result in beneficial physiologic responses. Specifically, several studies suggest that neonates may ventilate more effectively in a prone rather than in a supine position. This study tested the hypothesis that transcutaneous carbon dioxide tension (TcPCO2) would be lower in the prone than in the supine position in neonates with respiratory distress. Fourteen ventilated infants were studied. TcPCO2 was measured and recorded in prone, supine, and right-side-lying positions for each subject. There were no statistically significant differences in mean TcPCO2 values between the three positions (F = .45; df 2,39; P = .64). The relationship between TcPCO2 and PaCO2 values was stable (r = .88) during the studies. The results indicate that changing a neonate's position does not significantly alter transcutaneous carbon dioxide tension.