ACUTE HEMODYNAMIC-CHANGES OF PRESSURE-CONTROLLED INVERSE RATIO VENTILATION IN THE ADULT-RESPIRATORY-DISTRESS-SYNDROME - A TRANSESOPHAGEAL ECHOCARDIOGRAPHIC AND DOPPLER STUDY

Twelve patients with the adult respiratory distress syndrome were incl uded in this study and evaluated by transesophageal echocardiography a nd Doppler, assessing right and left ventricular intracardiac blood fl ow alterations with progressive increase of inspiration-to-expiration (I-E) ratios. Whereas midpulmonary artery flow parameters did not show any change, early left ventricular filling demonstrated a significant increase after switching the ventilatory mode from volume to pressure -controlled ventilation with 2:1 I-E ratio (end-inspiration: 39+/-26 c m with positive end-expiratory pressure [PEEP]-ventilation to 68+/-56 cm with pressure-controlled inverse-ratio ventilation, 2:1; p<0.01; at end-expiration, from 67+/-21 cm with PEEP-ventilation to 83+/-36 cm w ith pressure-controlled ventilation 1:1; p less-than-or-equal-to 0.05) , resulting probably from different ventilatory flow and pressure curv es. In the meanwhile, cardiac index demonstrated a significant augment ation (from 4.73+/-1.71 L/min.m2 to 5.56+/-1.66 L/min.m2; p<0.05). Pre ssure-controlled inverse ratio ventilation results in both respiratory and hemodynamic advantages as is demonstrated by this study.