Effect of hypothermic ventricular fibrillation on lung function in dogs undergoing cardiopulmonary bypass

    LI Zhanª²Qing, LI Liª²Gang, CHEN Chen, PU Guoª²Hua, LIU Zhiª²Yong, ZHANG Yu, CHEN Guoª²Sheng

    1Department of Cardiothoracic Surgery, Affiliated Hospital, North China Coal Medical College, Tangshan 063000, China, 2Department of Cardiothoracic Surgery, Beijing Aerospace Center Hospital, Beijing 100049, China

    ¡¾Abstract¡¿ AIM: To evaluate the effect of hypothermic ventricular fibrillation on lung function in dogs undergoing cardiopulmonary bypass(CPB). METHODS: Fourteen healthy adult dogs were randomly divided into 2 groups (n=7 per group): hypothermic fibrillation group (experimental group) and cold crystalloid cardioplegia group (control group). Operation was performed through the fourth right intercostal space under general anesthesia, which was followed by systemic hypothermia to 28¡æ. A standard CPB was performed in the control group. Ventricular fibrillation was induced by injecting 4¡æª²normal saline into pericardial cavity. The concentration of serum ILª²8 was measured by ELISA before CPB, at the 1st hour during CPB, at the end of CPB and at the 1st hour after CPB. Lung specimens were obtained before CPB and at the end of CPB. Lung compliance was used to evaluate lung function. RESULTS: The concentration of serum ILª²8 in the 2 groups was significantly different(P<0.05), so was it at various time points (P<0.05). No difference was found in the 2 groups before CPB. The serum ILª²8 level went up gradually after the initiation of CPB and reached its peak at the end of CPB. ILª²8 level decreased at the 1st hour after CPB, but it was still higher than that before CPB. Compared with that in the control group, the histopathological lesion in lungs was less severe in the experimental group. No statistical difference of lung compliance was found between the experimental and control groups before CPB, but significant difference was found at various time points between the two groups(P<0.05) after CPB. The lung compliance went down gradually after the initiation of CPB and reached the lowest point by the end of CPB. CONCLUSION: Compared with normal CPB, hypothermic ventricular fibrillation under cardiopulmonary bypass reduces the lesion of tissues and has some protective effects on lung function. ......