Automatic selection of breathing pattern using adaptive support ventilation.
OBJECTIVE
In a cohort of mechanically ventilated patients to compare the automatic tidal volume (VT)-respiratory rate (RR) combination generated by adaptive support ventilation (ASV) for various lung conditions.


METHODS
Prospective observational cohort study in the 11-bed medicosurgical ICU of a general hospital.


METHODS
243 patients receiving 1327 days of invasive ventilation on ASV.


METHODS
Daily collection of ventilator settings, breathing pattern, arterial blood gases, and underlying clinical respiratory conditions categorized as: normal lungs, ALI/ARDS, COPD, chest wall stiffness, or acute respiratory failure.


RESULTS
Overall the respiratory mechanics differed significantly with the underlying conditions. In passive patients ASV delivered different VT-RR combinations based on the underlying condition, providing higher VT and lower RR in COPD than in ALI/ARDS: 9.3ml/kg (8.2-10.8) predicted body weight (PBW) and 13 breaths/min (11-16) vs. 7.6ml/kg (6.7-8.8) PBW and 18 breaths/min (16-22). In patients actively triggering the ventilator the VT-RR combinations did not differ between COPD, ALI/ARDS, and normal lungs.


CONCLUSIONS
ASV selects different VT-RR combinations based on respiratory mechanics in passive, mechanically ventilated patients.
Arnal
Jean-Michel
JM
Hôpital Font Pré, Service de réanimation polyvalente, 1208 avenue du colonel Picot, 83100 Toulon, France. jean-michel@arnal.org
Wysocki
Marc
M
Nafati
Cyril
C
Donati
Stéphane
S
Granier
Isabelle
I
Corno
Gaëlle
G
Durand-Gasselin
Jacques
J
D000368:Aged; D003422:Critical Care; D005260:Female; D005602:France; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology; D012121:Respiration, Artificial / Q000379:methods*; D012128:Respiratory Distress Syndrome / Q000503:physiopathology; D015656:Respiratory Mechanics / Q000502:physiology*; D013990:Tidal Volume / Q000502:physiology