Lung volume effects on pharyngeal swallowing physiology. Laryngopharyngeal sensory testing with modified barium swallow as predictors of aspiration pneumonia after stroke. Laryngeal adductor reflex and pharyngeal squeeze as predictors of laryngeal penetration and aspiration. The Association between Laryngopharyngeal Sensory Deficits, Pharyngeal Motor Function, and the Prevalence of Aspiration with Thin Liquids Respiratory-swallow phase patterns and their relationship to swallowing impairment in patients treated for oropharyngeal cancer. The effects of lingual exercise in stroke patients with dysphagia.
The experiment was a prospect i ve , repeated- measures design intended to determine how the variation of lung volume affects specific measures of swallowing physiology . Swallows were recorded in 28 healthy subjects , who ranged in age from 21 to 40 yr ( mean age of 29 yr ) , by using simultaneous videofluoroscopy , bipolar intramuscular electromyography , and respiratory inductance plethysmography . Each subject swallowed three st and ardized pudding-like consistency boluses at three r and omized lung volumes : total lung capacity , functional residual capacity , and residual volume . The results showed that pharyngeal activity duration of deglutition for swallows produced at residual volume was significantly longer than those occurring at total lung capacity or at functional residual capacity . No significant differences were found for bolus transit time or intramuscular electromyography of the superior constrictor . The results of this experiment lend support to the hypothesis that the respiratory system may have a regulatory function related to swallowing and that positive subglottic air pressure may be important for swallowing integrity . Eventually , new treatment paradigms for oropharyngeal dysphagia that are based on respiratory physiology may be developed Improved diagnostic tests that can accurately identify subjects at high risk for aspiration pneumonia ( AP )  are needed . One measure of this accuracy is the false-negative rate ( FNR ) , which determines the failure of a test to identify a group at high risk . This study compares FNRs for AP among dysphagic stroke patients for two prognostic techniques : modified barium swallow ( MBS ) alone and MBS combined with laryngopharyngeal sensory discrimination testing ( MBS + LPSDT ) . MBS and LPSDT were performed within 4 weeks of stroke in 20 subjects who were prospect ively followed for at least 2 years to identify the frequency of AP . MBS identified 10 patients as not at risk based on the finding of no aspiration on initial MBS ; four of these patients developed AP ( FNR = 40 % ) . MBS + LPSDT identified five patients as not at risk based on the findings of neither aspiration nor bilateral sensory deficits ; none of these patients developed AP ( FNR = 0 % ) . The combination of MBS criterion ( aspiration ) with the LPSDT criterion ( bilateral sensory deficits ) improves prognostication of outcome in dysphagic stroke patients by identifying a subgroup at high risk for developing AP ( nonaspirators with bilateral deficits ) OBJECTIVES The contribution of laryngopharyngeal ( LP ) sensory deficits to the outcome of swallowing and the relationship between sensory and motor deficits in the laryngopharynx is unclear . The study purpose is to determine if patients with LP sensory and motor deficits are at increased risk for laryngeal penetration and aspiration during swallowing , and to determine the relationship between pharyngeal motor weakness and LP sensory deficits . MATERIAL S AND METHODS Endoscopic evaluation of swallowing with sensory testing was performed on 122 dysphagic patients who were prospect ively divided into two groups . The control group was 76 patients with normal sensitivity , determined by an intact laryngeal adductor reflex ( LAR ) on air pulse stimulation of the mucosa innervated by the superior laryngeal nerve . The study group was 46 patients with severe sensory deficits , determined by an absent LAR . Each group was given puree followed by thin liquid , noting presence or absence of laryngeal penetration and aspiration .  Pharyngeal muscle strength was assessed by noting presence or absence of pharyngeal contraction during voluntary adduction of the vocal folds ( pharyngeal squeeze ) . RESULTS In control subjects , with purees , 6 of 76 ( 7.90 % ) penetrated and 3 of 76 ( 3.94 % ) aspirated ; with thins , 26 of 76 ( 34.2 % ) penetrated and 13 of 76 ( 17.1 % ) aspirated . In the absent LAR group , with purees , 39 of 46 ( 84.8 % ) penetrated and 32 and 46 ( 69.6 % ) aspirated ; with thins , 46 of 46 ( 100 % ) penetrated and 43 of 46 ( 93.5 % ) aspirated . For both consistencies , the differences in prevalence of penetration and aspiration between groups was significant ( P < .0001 , chi2 ) . In control subjects , pharyngeal squeeze was impaired in 17 of 76 ( 22.4 % ) , with penetration of puree in 6 of 17 ( 35.3 % ) and aspiration in 3 of 17 ( 17.6 % ) . In the absent LAR group , squeeze was impaired in 41 of 46 ( 89.1 % ) , with penetration of puree in 39 of 41 ( 95.1 % ) and aspiration in 32 of 41 ( 78.0 % ) . The difference in the prevalence of pharyngeal weakness between groups was significant ( P < .0001 ) . The difference in the prevalence of penetration and aspiration was higher in the absent LAR/impaired contraction cohort than in the normal sensation/impaired contraction cohort ( P < .0001 ) . CONCLUSION Absence of the LAR and impaired pharyngeal squeeze puts patients with dysphagia at high risk for laryngeal penetration and aspiration compared with patients with an intact LAR and intact pharyngeal squeeze . There is a strong association between motor and sensory deficits in the laryngopharynx OBJECTIVE : The study goal was to evaluate the association among laryngopharyngeal sensory deficits , pharyngeal motor function , and the prevalence of aspiration with thin liquids . STUDY DESIGN AND SETTING : We conducted a prospect i ve study of 204 consecutive patients undergoing flexible endoscopic evaluation of swallowing with sensory testing and an assessment of pharyngeal motor function ( pharyngeal squeeze ) .  Patients were divided into 6 groups depending on the results of sensory and motor testing in the laryngopharynx . Subjects were given 5 mL of thin liquid , and the prevalence of aspiration in each group was compared . RESULTS : The mean age of the entire cohort was 65 years ( 58 % female ) . The prevalence of aspiration in patients with intact laryngopharyngeal sensation was 2 % ( 3 of 137 ) in persons with intact pharyngeal motor function and 29 % ( 2 of 7 ) when pharyngeal motor function was impaired ( P < 0.05 ) . The prevalence of aspiration in patients with a moderate decrease in laryngopharyngeal sensation was 0 % ( 0 of 9 ) in persons with intact pharyngeal motor function and 67 % ( 2 of 3 ) when pharyngeal motor function was impaired ( P < 0.05 ) . The prevalence of aspiration in patients with severely diminished or absent laryngopharyngeal sensation was 15 % ( 5 of 33 ) in persons with intact pharyngeal motor function and 100 % ( 15 of 15 ) when pharyngeal motor function was impaired ( P < 0.05 ) . CONCLUSION : Patients with severely diminished laryngopharyngeal sensation and pharyngeal motor function are at an extremely high risk of aspirating thin liquids ( 100 % ) . Moderate sensory deficits only appear to influence the prevalence of thin liquid aspiration in the presence of pharyngeal motor dysfunction . Severe laryngopharyngeal sensory deficits are associated with the aspiration of thin liquids regardless of the integrity of pharyngeal motor function . We assume that all persons with an insensate laryngopharynx aspirate thin liquids until proved otherwise . These results emphasize the relationship between laryngopharyngeal sensation and pharyngeal motor function in the evaluation of patients for suspected aspiration BACKGROUND Unstable respiratory-swallowing coordination has been associated with disorders and disease . The goals of this study were ( 1 ) to describe respiratory-swallow patterns in patients with dysphagia consequent to treatments for cancers of the oropharynx and ( 2 ) to determine the association between respiratory-swallow patterns , airway invasion , and overall severity of swallowing impairment . METHODS This prospect i ve , cross-sectional design compared respiratory-swallow patterns in 20 patients treated for oropharyngeal cancer and 20 healthy , age-matched control participants .  Nasal airflow direction was synchronously recorded with videofluoroscopic imaging in participants who swallowed 5-mL thin liquid barium boluses . RESULTS Respiratory-swallow patterns differed between groups . Most control participants initiated and completed swallowing bracketed by expiratory airflow . Swallowing in patients often interrupted inspiratory flow and was associated with penetration or aspiration of the bolus . CONCLUSIONS We suggest nonexpiratory bracketed respiratory-swallowing phase patterns in patients with oropharyngeal cancer may place patients at greater risk of airway penetration or aspiration during swallowing OBJECTIVE To examine the effects of lingual exercise on swallowing recovery poststroke . DESIGN Prospect i ve cohort intervention study , with 4- and 8-week follow-ups . SETTING Dysphagia clinic , tertiary care center . PARTICIPANTS Ten stroke patients ( n=6 , acute : < or = 3mo poststroke ; n=4 , chronic : > 3mo poststroke ) , age 51 to 90 years ( mean , 69.7y ) . INTERVENTION Subjects performed an 8-week isometric lingual exercise program by compressing an air-filled bulb between the tongue and the hard palate . MAIN OUTCOME MEASURES Isometric and swallowing lingual pressures , bolus flow parameters , diet , and a dysphagia-specific quality of life question naire were collected at baseline , week 4 , and week 8 . Three of the 10 subjects underwent magnetic resonance imaging at each time interval to measure lingual volume . RESULTS All subjects significantly increased isometric and swallowing pressures . Airway invasion was reduced for liquids . Two subjects increased lingual volume . CONCLUSIONS The findings indicate that lingual exercise enables acute and chronic dysphagic stroke patients to increase lingual strength with associated improvements in swallowing pressures , airway protection , and lingual volume
Penetration – aspiration is considered the most serious component of oropharyngeal dysphagia .
Clinicians regularly evaluate the pathophysiology of swallowing and postulate reasons or mechanisms behind penetration – aspiration .
In this article we share the results of a two-stage literature review design ed to eluci date the association between abnormalities in physiological measures of swallowing function and the occurrence of penetration – aspiration .