Effect of neostigmine versus dexamethasone on quality of intravenous regional anesthesia: a randomized double-blinded controlled study

Background Pain is a great problem after surgical trauma. Acute postoperative pain incidence was reported to be more than 60% and was not adequately controlled. The authors aimed to investigate the effect of neostigmine versus dexamethasone on the duration of anesthesia and postoperative analgesia when added to lidocaine in a Bier block. Materials and methods This randomized double-blind controlled study was carried out on 75 patients scheduled for elective surgeries under intravenous regional anesthesia (Bier block). They were randomly allocated into three groups: group C (n=25, received intravenous 3 mg/kg lidocaine 2%), group D (n=25, received intravenous 3 mg/kg lidocaine 2%+8 mg dexamethasone), and group N (n=25, received intravenous 3 mg/kg lidocaine 2%+0.5 mg neostigmine). Visual analog scale (VAS) was used postoperatively to assess pain. Sensory and motor block characteristics and duration of postoperative analgesia were evaluated. Results The pain scores with the postoperative VAS data were statistically significant lower in the group D patients than those of groups C and N at 90 min, 105 min, and 120 min (P<0.05). Moreover, it was found that no statistically significant differences of VAS values were recorded among the three studied groups preoperatively and postoperatively at 15, 30, 45, 60, and 75 min. Duration of the postoperative analgesia was significantly longer in group D than group C and group N. Conclusion The addition of dexamethasone 8 mg to lidocaine 2% (3 mg/kg) during intravenous regional anesthesia provided better postoperative analgesia. When compared with the control group or the neostigmine group, dexamethasone increased the duration of postoperative analgesia.