Effect of a single bolus of dexamethasone on intraoperative and postoperative pain in unilateral inguinal hernia surgery.

BACKGROUND AND AIMS

Opioids are commonly used to provide perioperative analgesia, but have many side-effects. Addition of co-analgesics results in reducing the dosage and hence the side-effects of opioids. The objective of this study was to compare the analgesic efficacy of fentanyl (1 micro/kg(-1)) administered alone, with fentanyl (0.75 micro/kg(-1)) and dexamethasone (8 mg) combination, in patients undergoing day care unilateral inguinal hernia repair.

MATERIAL AND METHODS

Patients scheduled for the day care unilateral inguinal hernia repair were randomized to receive either saline and fentanyl 1 micro/kg(-1) (control group) or 8 mg dexamethasone with fentanyl 0.75 micro/kg(-1) (study group) immediately before induction of anesthesia in a double-blind clinical trial. Anesthesia technique and rescue analgesia regimen were standardized. Intraoperatively, pain was assessed based on hemodynamic variability and postoperatively by visual analog scale.

RESULTS

The mean heart rate, systolic and the diastolic blood pressure at 1, 5, 20 and at 30 min after incision, were significantly higher in the control group (P ≤ 0.001) when compared to the study group. Intra-operative rescue analgesia was required in 32 (100%) and 19 (59.4%) patients in control group and study group respectively (P = 0.0002). Mean pain scores measured at fixed time periods postoperatively were significantly higher in the control group when compared to study group (P ≤ 0.001). Postoperative rescue analgesia was needed in 32 (100%) versus 24 (75%) patients in the control group and study group respectively, but this difference was not statistically significant (P = 0.285).

CONCLUSION

We conclude that the addition of 8 mg of preoperative intravenous dexamethasone to 0.75 micro/kg(-1) fentanyl was effective in reducing intraoperative and postoperative pain in the 1(st) h after unilateral inguinal hernia surgery.