Mechanisms of burn shock protection after severe scald injury by cold-water treatment

Following a 3-second subxiphoid immersion of shaved, unresuscitated guinea pigs in 100 degrees C water, cardiac output (CO), mean systemic blood pressure (BP), total peripheral resistance (TPR), hematocrit (HCT), serum histamine (SH), and serum lactate (SL) were measured in untreated and cold-water treated animals up to 24 hours after injury. Animals receiving cold-water treatment (CWT) were immersed in 15 degrees C water for 15 minutes immediately after scald injury. CWT significantly (p less than 0.05) reduced SH and SL for up to 8 and 24 hours, respectively, after injury compared to untreated injured animals. HCT of CWT animals remained significantly lower than that of untreated animals for the first 8 hours after injury. However, CWT-animal HCT was not significantly different from control-animal HCT for this same period. CWT-animal BP was significantly greater than untreated-animal BP for the first 8 hours after injury. CWT- and untreated-animal TPR progressively rose after injury; however, at 24 hours after injury CWT-animal TPR was significantly reduced to 87% +/- 18.0 of preinjury values while untreated-animal TPR was maximally elevated to 170% +/- 10.0 of preinjury values. At 4 hours after injury CO of both untreated and SWT animals was significantly depressed at 56% +/- 3.0 and 50% +/- 10.0 of preinjury values, respectively. However, by 24 hours after injury untreated-animal CO remained depressed at 52% +/- 3.0 while CWT-animal CO was significantly improved at 92% +/- 19.0 of preinjury values. These studies document a beneficial hemodynamic response of severely burned animals after CWT and further verify the phenomenon of cold inhibition of burn wound tissue histamine release after severe scald injury. A correlation between decreased serum histamine and lactate levels and improved cardiovascular function following severe scald injury and CWT is also suggested.