To observe the effects and safety of different doses of alfentanil injection on hyperalgesia after continuous infusion of remifentanil injection in patients undergoing laparoscopic cholecystectomy.

The patients scheduled to undergo laparoscopic cholecystectomy were divided into group A, group B, group C and group D. Ten minutes before the end of the surgery, groups A, B and C were intravenously injected with alfentanil at doses of 5, 15 and 25 μg·kg^-1, respectively, while group D was injected with 0.9% NaCl. The hemodynamics indices [before anesthesia induction (T₀), 5 minutes after induction (T₁), during intubation (T₂), at skin incision (T₃), during extubation (T₄), 10 minutes after extubation (T₅)], quality of awakening, analgesia and sedation scores, incidence of postoperative hyperalgesia, inflammatory factors and safety were compared among the 4 groups.

A total of 42 patients in each group were included in the statistical analysis. At T₄, mean arterial pressure (MAP) values in groups A, B, C and D were (92.81±10.31), (87.50±10.33), (85.60±9.69) and (98.48±7.07) mmHg, respectively; heart rate (HR) values were (87.36±9.25), (81.76±9.35), (80.24±9.38) and (92.83±9.73) beat·min^-1, respectively; at T₅, MAP values were (95.40±8.63), (90.19±8.79), (89.71±8.86) and (99.48±8.72) mmHg, respectively; HR values were (92.31±8.56), (87.55±8.84), (86.24±8.64) and (97.33±8.51) beat·min^-1, respectively; extubation time were (9.07±1.02), (9.38±1.25), (11.48±1.58) and (10.74±1.38) min; spontaneous breathing recovery time were (6.52±1.27), (6.86±1.28), (8.38±1.53) and (7.29±1.13) min; and PACU stay time were (22.64±4.57), (23.69±4.25), (32.95±4.62) and (27.26±4.98) min for groups A, B, C, and D, respectively; the incidence of hyperalgesia at 2 h postoperation were 4.76% (2 cases/42 cases), 2.38% (1 cases/42 cases), 0 and 21.43% (9 cases/42 cases), and at 24 h postoperation were 9.52% (4 cases/42 cases), 4.76% (2 cases/42 cases), 0 and 23.81% (10 cases/42 cases) in groups A, B, C, and D, respectively. Differences between group D and the other three groups were statistically significant (all P<0.05). There were no obvious adverse drug reactions in groups A and D. Adverse drug reactions in group B included nausea and vomiting, and adverse drug reactions in group C included respiratory depression. The total adverse drug reactions in groups A, B, C, and D were 0% (0 cases/42 cases), 2.38% (1 case/42 cases), 4.76% (2 cases/42 cases), and 0% (0 cases/42 cases), respectively, and there were no statistically significant differences (all P>0.05).

Compared with low dose alfentanil injection, high dose alfentanil injection applied in cholecystectomy can reduce hyperalgesia, effectively relieve pain, and alleviate inflammatory response, but the effect on improving the recovery quality of patients is not obvious.