Rapid body cooling by cold fluid infusion prolongs survival time during uncontrolled hemorrhagic shock in pigs.
OBJECTIVE
The purpose of this study was to examine whether cold fluid infusion could rapidly decrease the core temperature and prolong survival during uncontrolled hemorrhagic shock in pigs.


METHODS
Fourteen pigs under light halothane anesthesia and spontaneous breathing underwent initial blood withdrawal of 25 mL/kg over 15 minutes, followed by uncontrolled hemorrhage (5-mm aortotomy). Immediately after the aortotomy, the pigs were randomized to receive 500 mL lactated Ringer's solution at either 4 degrees C (group 1, n = 7) or 37 degrees C (group 2, n = 7) over 20 minutes through the internal jugular vein and observed until their death or for a maximum of 240 minutes.


RESULTS
The pulmonary artery temperature of group 1 decreased to 35.5 degrees +/- 0.3 degrees C after the infusion, then remained at 35.5 degrees C during the observation period. Pulmonary artery temperature values of group 2 remained at around 37.5 degrees C throughout the experiment. The mean survival time was 220 +/- 45 minutes in group 1 versus 136 +/- 64 minutes in group 2 (p < 0.05, life table analysis). The additional intraperitoneal blood loss of group 1 was similar to that of group 2 (9 +/- 4 g/kg vs. 10 +/- 5 g/kg).


CONCLUSIONS
In lightly anesthetized pigs during uncontrolled hemorrhagic shock, infusion with 4 degrees C lactated Ringer's solution (which seems to be feasible in the clinical setting) decreases the core temperature rapidly and prolongs survival.
Norio
Hirofumi
H
Department of Traumatology and Critical Care Medicine, National Defense Medical College, Tokorozawa, Saitama, Japan.
Takasu
Akira
A
Kawakami
Masato
M
Saitoh
Daizoh
D
Sakamoto
Toshihisa
T
Okada
Yoshiaki
Y
D000818:Animals; D001784:Blood Gas Analysis; D001835:Body Weight; D006439:Hemodynamics; D007036:Hypothermia, Induced / Q000379:methods*; D007262:Infusions, Intravenous; D015993:Life Tables; D012771:Shock, Hemorrhagic / Q000401:mortality / Q000628:therapy*; D013552:Swine; D013997:Time Factors