PERMISSIVE HYPERCAPNIA VENTILATION IN PATIENTS WITH SEVERE PULMONARY BLAST INJURY

Objectives: To describe our experience with the use of limited peak in spiratory pressure (PIP), volume-controlled ventilation, and permissiv e hypercapnia in patients with severe pulmonary blast injury. Methods: Patients with pulmonary blast injury were ventilated using volume-con trolled, synchronized intermittent mandatory ventilation. Whenever PIP exceeded 40 cm H2O, the tidal volume was decreased to maintain PIP at less than 40 cm H2O. Whenever the arterial pH fell below 7.2, the ven tilator rate was increased in increments of 2 breaths per minute until the arterial pH rose to 7.25. Results: Between 1994 and 1996, 17 pati ents with severe pulmonary blast injury (10 from enclosed space explos ions and seven from open space ones), requiring mechanical ventilatory support were admitted to our intensive care unit. Four patients devel oped increasing Paco(2) levels (to 93 +/- 12 mm Hg) associated with th e reduction in arterial pH that was corrected by increasing the ventil ator rate. There was evidence of ventilator-induced pulmonary barotrau ma. Of the 17 patients, 15 patients (88%) survived. Conclusions: Limit ed PIP in a volume-controlled ventilation is a useful and safe mode of mechanical ventilation in patients with pulmonary blast injury.