Establishment of hypothermia-induced suspended animation for delayed resuscitation animal model in rats

XIAO Xiong; GAO Yan; LYU Ying; LIANG Bing; JIN Hai; ZHANG Xin; LIU Yu

doi:10.16048/j.issn.2095-5561.2024.02.11

Abstract：Objective To investigate the feasibility of rats model of hypothermia-induced suspended animation for delayed resus-citation which were carried out cardioplegia and circulatory arrest induced by systemic hyperkalemia. Methods Six healthy male Sprague-Dawley rats with SPF grade were selected to cannulate according to the cardiopulmonary bypass rat model,and bled to estab-lish the hemorrhagic shock model. Then,cold organ preservation solution(HTK solution) was continuously perfused to induce cardio-plegia and systemic hypothermia through the artery catheter,and circulatory arrest was induced when the core temperature dropped to 15℃. Hemoperfusion was restored after 60 minutes of circulatory arrest until restoration of stable and normal heart rate. Results Six rats could maintain stable spontaneous rate with cardiopulmonary bypass,but only one rat could wean off cardiopulmonary bypass (cardiopulmonary bypass time:152 min).The rats were bleeding (4.2±0.8) ml during the establishment of shock model. During hypo-thermia-induced suspended animation,the consumption of HTK solution was (135±14)ml,and the induction time from HTK solution perfusion to temperature dropping to 15 ℃ was (27±4)min. After reperfusion,the concentration of potassium ion was (8.9±4.3) mmol/L in vivo.The volume of allogeneic blood transfusion was (11±1)ml during delayed resuscitation. The lactate levels gradually rised after induction of shock,reached to the peak at 10 minutes after restoration of circulation,and gradually showed a downward trend with the extension duration of cardiopulmonary bypass support. Conclusions Systemic perfusion with organ preservation solution (HTK solution) can establish rats model of hypothermia-induced suspended animation for delayed resuscitation,and this method laids the foundation of the study on damage and protection mechanism of hypothermia-induced suspended animation for delayed resuscitation on brain,heart,liver,kidney and other important organs.