Synergistic effect of acute renal failure and respiratory failure in the surgical intensive care unit.

A retrospective evaluation of the effect of renal and respiratory failure on mortality in our surgical intensive care unit was undertaken. The coexistence of combined renal and respiratory failure had a synergistic adverse effect on survival. Combined pulmonary and kidney failure appeared to develop simultaneously. A subset of patients with severe prerenal azotemia but without uremia had the highest mortality. These results are not consistent with the simple combination of single systems failure but rather suggest that renal and respiratory failure are makers of a generalized underlying defect.