Bi-level positive airway pressure ventilation maintains adequate ventilation in post-polio patients with respiratory failure.
BACKGROUND
Patients suffering from post-polio syndrome still contribute significantly to the number of patients with chronic respiratory failure requiring home mechanical ventilation (HMV). Many of these patients are treated either with invasive (tracheostomy) or non-invasive (nasal mask) controlled mechanical ventilation i.e. volume-controlled ventilation (VCV). In this group of patients, we have previously shown that bi-level pressure support ventilation (bi-level PSV) decreases the oxygen cost of breathing. The aim of this study was to compare the effect of bi-level PSV, with special regard to the adequacy of ventilation and the oxygen cost of breathing, during the patients' ordinary VCV and spontaneous breathing.


METHODS
Eight post-polio patients on nocturnal VCV were investigated. Five of them were tracheostomized and three of them used a nasal mask. Work of breathing was analysed by assessing differences in oxygen consumption (VO2) using indirect calorimetry. Blood gases were obtained regularly to assess adequacy of ventilation.


RESULTS
Bi-level PSV decreases the oxygen cost of breathing in post-polio patients with respiratory failure without decreasing ventilation efficiency. Furthermore, PaCO2 decreased significantly using this mode of ventilation (P < 0.05).


CONCLUSIONS
In this study, it was shown that bi-level PSV reduces the oxygen cost of breathing and gave a significant decrease in PaCO2 in PPS patients. These data suggest that bi-level PSV ventilation maintains adequate ventilation in patients who suffer from post-polio syndrome with respiratory failure.
Gillis-Haegerstrand
C
C
Department of Anaesthesiology and Intensive Care, Karolinska Institutet, Danderyd Hospital, Stockholm, Sweden. caroline.haegerstrand@ds.se
Markström
A
A
Barle
H
H
D000368:Aged; D001784:Blood Gas Analysis; D015992:Body Mass Index; D002153:Calorimetry, Indirect; D002245:Carbon Dioxide / Q000097:blood; D004734:Energy Metabolism; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016262:Postpoliomyelitis Syndrome / Q000628:therapy*; D012121:Respiration, Artificial; D012129:Respiratory Function Tests; D012131:Respiratory Insufficiency / Q000209:etiology* / Q000628:therapy*; D015656:Respiratory Mechanics / Q000502:physiology
D002245:Carbon Dioxide