Impact of different analgesic depths and abdominal trauma of different severities on stress and recovery of rats undergoing total intravenous anesthesia

Abstract

A number of animal models have been developed to examine the pathophysiological consequences of surgical procedures, but anesthetic methods, monitoring, and management measures in these models are very different from those used in humans. This study was designed to create a rat model of abdominal surgery using anesthetic methods and perioperative treatment similar to those used in the clinic and to investigate the effects of different injury severities and depths of anesthesia and analgesia on surgical stress and postoperative recovery. Abdominal skin/muscle incision was compared with exploratory laparotomy in rats under propofol intravenous anesthesia, accompanied by perioperative measures such as oxygen inhalation, fluid infusion, warmth, blood gas analysis, and infection prevention. Stress indices (mean arterial pressure, heart rate, blood glucose, and plasma corticosterone) were monitored during anesthesia and surgery, and recovery indicators (body weight, food consumption, and pain) were measured after surgery. In addition, animals undergoing laparotomy were subjected to low and high dosages of propofol and sufentanil, in order to examine the relationship between anesthetic and analgesic depth and stress on recovery. Exploratory laparotomy induced a greater stress response and caused slower postoperative recovery as measured than somatic injury. High-dose sufentanil downregulated plasma corticosterone and improved postoperative recovery more effectively than high-dose propofol (P<0.05). Taken together, a rat model of abdominal surgery using anesthetic methods and perioperative treatment similar to those used in the clinic was successfully developed. It showed a positive correlation between severity of surgical trauma and stress response and postoperative recovery and a significant role of adequate analgesia in reducing surgical stress and improving postoperative recovery.

Keywords:

• animal model
• injury severity
• stress response
• postoperative recovery
• analgesic depth
• abdominal trauma

Acknowledgments

Dr Duan Bin and Dr Ye Zhi offered technology support in this experiment. Experimental equipment and technology support were given by the Animal Experimental Center of Xiangya Hospital of Central South University. This work was funded by the National Natural Science Foundation of China, grant number 31200736.

Author contributions

Hai-ming Huang contributed to study design, definition of intellectual content, literature research, clinical studies, experimental studies, data acquisition, and manuscript preparation. Jun Cao helped in literature research, clinical studies, experimental studies, and manuscript editing. Lin-mei Zhu was involved in literature research, experimental studies, data acquisition, and manuscript preparation. Yu-qing Chen contributed to experimental studies, data acquisition, and manuscript preparation. Fu-ding Lu contributed to data analysis. Hong-wei Cai was the guarantor of integrity of the entire study and contributed to study concepts, study design, definition of intellectual content, data analysis, and manuscript editing. All authors contributed toward data analysis, drafting and revising the paper and agree to be accountable for all aspects of the work.

Disclosure

The authors report no conflicts of interest in this work.