[Low flow technique to perform static pressure-volume curve during mechanical ventilation].
OBJECTIVE
To describe a fast, simple method to acquire static pressure-volume (P-V) curve of the respiratory system and to compare it with airway occlusion technique.


METHODS
ARDS sheep model was induced by intravenously infusing 3-6 micrograms/kg LPS, static P-V curves were determined by low flow technique and airway occlusion technique. Static compliance (Cst), lower inflection point (Pinfd and Pinfb) and airway pressure were compared between the two methods.


RESULTS
Pinf were (8.91 +/- 0.82) cm H2O and (8.59 +/- 0.78) cm H2O determined by low flow technique and airway occlusion technique respectively, the correlation between which was good (r = 0.93, P < 0.05). Cst determined by low flow technique was similar to that determined by airway occlusion technique [(19 +/- 7) L/cm H2O vs (20 +/- 7) L/cm H2O, P > 0.05]. The time needed to acquire a static P-V curve by low flow technique was 3-4 minutes versus 30-35 minutes by airway occlusion technique.


CONCLUSIONS
Accuracy and reliability of low flow technique are sufficient for clinical use, it is much less time consuming than the airway occlusion technique.
Guo
F
F
Department of Critical Care Medicine, First Affiliated Hospital of Medical College, Southeast University, Nanjing 210009, China.
Qiu
H
H
Tan
Y
Y
D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D006874:Hydrostatic Pressure; D008168:Lung / Q000503:physiopathology*; D008297:Male; D012121:Respiration, Artificial; D012128:Respiratory Distress Syndrome / Q000503:physiopathology*; D012756:Sheep