ObjectiveTo analyze the death causes of postoperative early-stage after orthotopic liver transplantation (OLT) in rats, and to provide appropriate treatment strategies. MethodsThree hundreds of rat OLT models were performed by modified Kamada two-cuff technique. Operation time of each stage during OLT and postoperative survival time of rats were recorded and analyzed. According to survival time, the rats were divide into 4 groups:intraoperative death group (rats died during operation), < 6 hours group, 6-24 hours group, and > 24 hours group. Then comparison of operation time of each stage during OLT in rats of 4 groups was performed, and reasons of death during 24 hours after OLT were analyzed. ResultsOf the 300 OLT models, 37 rats died during operation (12.33%), 51 rats died within 6 hours after operation (17.00%), 76 rats died during 6-24 hours after operation (25.33%), and 136 rats survived longer than 24 hours (45.34%). The most common death causes of < 6 hours group were as follows:lose too much blood during the operation (27.45%, 14/51), postoperative bleeding (27.45%, 14/51), and vascular embolization (15.69%, 8/51). However, the most common death causes of 6-24 hours group were as follows:angiostenosis (27.63%, 21/76), postoperative bleeding (21.05%, 16/76), and pulmonary edema (19.74%, 15/76). There were significant differences in the cold ischemia time and anhepatic phase among the 4 groups (P < 0.05). The cold ischemia time and anhepatic phase of intraoperative death group were longer than those of other 3 groups (P < 0.05), in addition, the cold ischemia time of > 24 hours group was shorter than those of other 3 groups (P < 0.05). ConclusionsThere are many reasons leading to the early death after OLT. The long time of anhepatic phase and the cold ischemia time, intraoperative and postoperative bleeding, thrombosis, angiostenosis, and pulmonary edema are key factors for the improvement of prognosis in rats after OLT operation. Improvements of the reasons above are helpful to improve the successful rate of modeling and quality of OLT rats.