Hypothermia Is Associated With Improved Outcomes in a Porcine Model of Hemorrhagic Shock

Abstract

: In our porcine model, we found that simulating mild and severe levels of environmental hypothermia during early resuscitation after hemorrhage was associated with a significantly decreased mortality rate. Furthermore, markers of cellular stress and organ dysfunction, including lactate levels and the base deficit, were lower in hypothermic animals. Decreasing oxygen consumption with hypothermia may, in part, explain the protective effects observed with hypothermia.

Effects of environmental hypothermia on hemodynamics and oxygen dynamics in a conscious swine model of hemorrhagic shock

“…[7,8] Obviously, it was the unanesthetized model of HS that made experimental results contrary to those of George's. If pigs' normal p h y s i o l o g i c a l r e a c t i o n w a s b l o c k e d u n d e r l o w temperature circumstance, results derived from these animals were not reliable.…”

“…[6] In contrast with clinical data, studies in experimental models have consistently showed World J Emerg Med, Vol 3, No 2, 2012 that mild hypothermia induced by surface cooling or intravenous infusion of ice-cold fl uids improves survival during and after HS. [7][8][9] In a previous study, we found that HS model with anesthetized swine was different from that of clinical reality. This might explain the contradiction between experimental studies and clinical scenario.…”

Induced Hypothermia Preserves the Functional Enterocyte Mass in A Porcine Multiple Trauma Model

“…Induced hypothermia offers a promising approach to attenuating posttraumatic organ damage (19,27). In particular, the microvascular mucosal oxygenation appears to be improved after severe traumatic insults (22,28).…”

“…Different experimental studies have shown that induced hypothermia might be able to attenuate the inflammatory response, reduce organ damage, and improve the outcome of severe trauma (17)(18)(19). The important mechanisms associated with these beneficial effects are maintaining aerobic metabolism and reducing oxygen demand (20,21).…”

Experimental Models of Hemorrhagic Shock: A Review

“…The mean arterial pressure varies between 20 and 55 mm Hg depending on the examiner and the species. This hypotensive shock state is maintained for 15 min, or in some studies for more than 3 h [53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76](table 3). …”