Effects of Adding Low-Dose Ketamine to Remifentanil-Midazolam Infusion under Topical Anesthesia on Pain Relief after Nasal Bone Fracture

Document Type : Original Article (s)

Authors

1 Assistant Professor, Department of Anesthesiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran

2 Associate Professor, Department of Anesthesiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran

3 Student of Medicine, School of Medicine AND Student Research Committee, Isfahan University of Medical Sciences, Isfahan, Iran

Abstract

Background: Pain relief after nasal bone fracture surgery is unsatisfactory. The present study aimed to evaluate the effects of adding low-dose ketamine to remifentanil-midazolam infusion under topical anesthesia on pain relief after nasal bone fracture. Methods: In a controlled study, 68 nasal bone fracture surgery candidates were allocated to two groups receive infusion of 2 µg/kg remifentanil and 0.05 mg/kg midazolam plus 0.5 mg/kg of either ketamine (ketamine group) or placebo (control group). Pain intensity was assessed using a visual analogue scale. Patient satisfaction and the amount of rescue analgesic used were recorded until 60 minutes after surgery. Repeated measures analysis of variance (ANOVA) was used to analyze the data. Findings: In the ketamine group, pain intensity 0, 15, 30, 45, and 60 minutes after operation was 3.5 ± 2.1, 1.2 ± 2.0, 1.8 ± 2.4, 1.3 ± 2.1, and 1.9 ± 2.2, respectively. The corresponding values in the control groups were 3.7 ± 2.2, 8.6 ± 2.0, 4.7 ± 1.2, 3.1 ± 1.2, and 3.7 ± 0.9. The difference between the two groups was statistically significant (P = 0.001). Moreover, patient satisfaction in the ketamine group was higher than the control group (P = 0.005). The dosage of rescue pethidine was significantly lower in the ketamine group compared to the control group (P = 0.045). Conclusion: This study showed that adding 0.5 mg/kg ketamine to 2 µg/kg remifentanil and 0.05 mg/kg midazolam improved postoperative pain relief. Keywords: Ketamine, Postoperative pain, Nasal bone fracture, Infusion, Topical anesthesia