VENTILATION INDEX AND OUTCOME IN CHILDREN WITH ACUTE RESPIRATORY-DISTRESS SYNDROME

The purpose of this investigation was to determine the predictive valu e of the ventilation index (VI) in children with acute respiratory dis tress syndrome (ARDS). We performed a 10-year retrospective chart revi ew of children who were admitted to the Pediatric Intensive Care Unit with a diagnosis of ARDS. Acute respiratory distress syndrome was defi ned as acute onset of diffuse, bilateral pulmonary infiltrates of nonc ardiac origin, and severe hypoxemia, defined as the ratio of the arter ial partial pressure of oxygen to the fraction of inspired oxygen of < 200 and a positive end expiratory pressure of 6 cmH(2)O or greater. Re cords of daily arterial blood gas results and ventilator settings were reviewed, and the ventilation index (VI = partial pressure of arteria l CO2 x peak airway pressure x respiratory rate/1,000) was calculated each time the measurements were made. These values were correlated wit h outcome (survival or nonsurvival). The VI was not different at the t ime of diagnosis of ARDS in the patients who lived, compared with thos e who subsequently died. However by 3 to 5 days after study entry, the VI of nonsurvivors was significantly higher than for survivors (P < 0 .05). The VI for survivors remained between 30 and 35 throughout the s tudy period, whereas the VI of nonsurvivors continued to increase with time. A VI of >65 predicted death with a specificity and positive pre dictive value of >90% on days 3 through 9. We conclude that the VI pro vides a reliable prognostic marker in children with ARDS, and its incr ease above 65 indicates a need for orderly intervention with alternati ve modalities of care. Pediatr Pulmonol, 1998; 26:125-128, (C) 1998 Wi ley-Liss, Inc.