The use of a normal tidal volume in patients with progressive loss of alveolar airspace may increase inspiratory pressure and overdistend remaining functional alveoli. Permissive hypercapnia (PH) is a ventilator management technique that emphasizes control of alveolar pressure, rather than PCO2. The purpose of this study was to determine if the use of PH is associated with an improved outcome from adult respiratory distress syndrome (ARDS). Over a 2-year period, 39 trauma patients were treated for ARDS. Permissive hypercapnia was used in 11, and the remaining patients were treated conventionally. Demographics and risk factors were well matched in PH patients and controls. The duration of mechanical ventilation was greater in PH patients [49.2 +/- 15.2 vs. 20.8 +/- 10 days(p < 0.01)]. Survival was also greater in the PH group [91% vs. 48% (p < 0.01)]. A reduction in intensity of mechanical ventilation is associated with a prolongation of ventilatory support and an improved outcome from ARDS.
From the Department of Surgery, Harborview Medical Center, University of Washington School of Medicine, Seattle, Washington.
This study was supported in part by the Harborview Injury Prevention and Research Center, CDC Grant R40-CCR-00-2750.
Presented at the 54th Annual Session of the American Association for the Surgery of Trauma, September 29-October 1, 1994, San Diego, California.
The reader is referred to the Clinical Management Update, a new section beginning this issue on page 985.
Address for reprints: Larry M. Gentilello, MD, Department of Surgery, Harborview Medical Center, 325 Ninth Avenue, ZA-16, Seattle, WA 98104.