Novel Means to Classify Response to Resuscitation in the Severely Burned: Derivation of the KMAC Value.

摘要

Background: Resuscitation fluid rates following burn are currently guided by a weight and burn size formulae, then titrated to urine output. Traditionally, 24 h resuscitation is reported as volume of resuscitation received without direct consideration for the physiologic response. We propose an input-to-output ratio to describe the course of burn resuscitation and predict eventual outcomes. Methods: We reviewed admissions to a burn center from January 2003 through August 2006. Inclusion criteria were >/= 20%TBSA, admission </= 8 h after burn, and survived >/= 24 h. Demographics, input volume and urine output, and clinical outcomes were recorded. A ratio of input volume (cc/kg/%TBSA/h) to urine output (cc/kg/h) was calculated at 24 h. The ratio of fluid intake to urine output reflecting an expected response was developed: 4 cc/kg/%TBSA/ 24 h (0.166 cc/kg/%TBSA/h) divided by 0.5 1.0 cc urine/kg/h for an expected range 0.166 0.334. Subjects were classified based upon the ratio: over-responders (<0.166), expected (0.166 0.334), or under-responders (>0.334). Clinical outcomes were compared and concordance of classification to values was calculated at 12 h. Results: 102 subjects met inclusion criteria; 29 in the over-responders, 37 in the expected, and 36 in the under-responders. Resuscitation volume was directly proportional to the calculated ratio while urine output was inversely proportional. Group mortality was 21%, 11%, and 44%, respectively, with a significant difference between the expected and under-responders ( p < 0.002). We found decreased ventilator-free days in the under-responders, and when deaths were excluded, decreased ICU-free days as well ( p < 0.05). Concordance of paired data gathered at 12 h and 24 h was 67% for the under-responder group. Conclusions: We describe a novel ratio to classify acute resuscitation after severe burn including the patient s response. Such a classification is associated with eventual outcomes.