Abstract

Pain after laparoscopic hysterectomy can lead to strong stress response, increase blood pressure and heart rate, restless during the awakening period. Preemptive analgesia is one of the methods to relieve postoperative pain. The purpose of this study is to explore the feasibility and safety of hydromorphine hydrochloride in preemptive analgesia, and to provide reference for clinical application. Two hundred American Society of Anesthesiologists I-II patients undergoing laparoscopic hysterectomy under endotracheal intubation general anesthesia from September 2019 to October 2020 were randomly divided into observation group (n=100) and control group (n=100) according to random number table. Patients in both groups were given intravenous rapid induction tracheal intubation combined with general anesthesia. 15 min before skin incision, hydromorphinone hydrochloride 15 μg/kg (diluted to 10 ml with normal saline) was injected intravenously in the observation group, while normal saline 10 ml was injected into the control group. Visual analogue score was used to evaluate the analgesic effect after tracheal extubation. Venous blood samples were taken 5 min before anesthesia and after extubation, and the levels of plasma epinephrine, norepinephrine and dopamine were measured. The mean arterial pressure and heart rate of the two groups were recorded before anesthesia, after operation, immediately after extubation, 10 min after extubation and 30 min after extubation. Ramsay sedation scale was used to evaluate the sedation of patients with 10 min, 30 min and 1 h after endotracheal tube extubation. Riker Sedation-Agitation Scale was used to observe the occurrence of restlessness in the recovery period within 24 h after operation. There was no significant difference in basic characteristics between the two groups (p>0.05). Visual analogue score: compared with the control group, the visual analogue scores at 10 min after extubation, 30 min after extubation, 1 h, 2 h, 4 h, 6 h and 12 h after endotracheal tube extubation in the observation group were significantly lower than those in the control group. There was no significant difference in the levels of plasma epinephrine, norepinephrine and dopamine between the two groups before anesthesia. After extubation, the levels of plasma epinephrine, norepinephrine and dopamine in the 5 min control group were significantly higher than those in the observation group (p<0.05). Hemodynamics (mean arterial pressure and heart rate in the control group were significantly higher than those in the observation group after operation, immediately after extubation, 10 min after extubation and 30 min after extubation in mean arterial pressure and heart rate): groups, and the difference was statistically significant. There was no significant difference in spontaneous respiratory recovery time and extubation time between the two groups (p>0.05). Ramsay sedation score: there was no difference between the two groups. Preemptive analgesia with hydromorphine hydrochloride in patients undergoing laparoscopic hysterectomy under general anesthesia has good analgesic effect, less postoperative adverse reactions, and can effectively inhibit cardiovascular reactions during recovery.