Computer simulation of hypothermia during "damage control" laparotomy.
"Damage control" is a surgical strategy for the staged repair of severe trauma that aims to avoid an irreversible physiologic insult marked by a self-propagating combination of hypothermia, coagulopathy, and acidosis. The point beyond which the physiologic insult becomes irreversible, however, remains ill-defined. The aim of this study was to address this problem by means of a dynamic computer model of heat loss during laparotomy for exsanguinating hemorrhage. A single compartment model was developed using a graphic modeling tool and was implemented to calculate the time interval from the beginning of laparotomy to a core temperature of 32 degrees C, which is a marker of irreversible physiologic derangement in injured patients. A series of simulation runs showed that the exposed peritoneum is the dominant factor contributing to heat loss; the bleeding rate has a less marked effect. Elevation of the ambient temperature and rapid abdominal closure are effective interventions available to the surgeon to modify the heat loss curve. This study shows that during a "damage control" laparotomy for exanguinating hemorrhage the window of opportunity for salvage before the onset of an irreversible physiologic insult is no longer than 60 to 90 minutes.
Hirshberg
A
A
Department of Surgery, The Chaim Sheba Medical Center, Tel Hashomer 52621, Israel.
Sheffer
N
N
Barnea
O
O
D003198:Computer Simulation; D006470:Hemorrhage / Q000601:surgery*; D006801:Humans; D007035:Hypothermia / Q000209:etiology*; D009104:Multiple Trauma / Q000601:surgery*