Comparison of intravenous bolus and infusion of dexmedetomidine on characteristics of subarachnoid block

Abstract

Aims:Dexmedetomidine is very dynamic drug, used for analgesia, sedation, blunting the laryngoscopic responses and as adjuvants in regional anesthesia. Studies have shown that intravenous (iv) dexmedetomidine given during spinal anesthesia increases the quality of subarachnoid block (SAB). In this study, we compare the two iv regimen of dexmedetomidine on analgesic effect of spinal anesthesia. One is bolus dose of dexmedetomidine and other is infusion during the surgery, both given after induction of spinal anesthesia.Subjects and Methods:Sixty American Society of Anesthesiologists I and II patients scheduled to undergo surgeries under SAB were randomly allocated into two groups namely B and I. After SAB with 3.0 ml of bupivacaine 0.5% heavy, Group B received 0.5 μg/kg of dexmedetomidine bolus over 15 min, Group I received 0.5 μg/kg/h of dexmedetomidine infusion until the end of surgery.Statistical Analysis Used:All parametric data were statistically analyzed using Student's t-test and nonparametric data analyzed using Chi-square test and Fischer exact test as appropriate. P < 0.05 was considered as statistically significant. Statistical analysis was performed using the SPSS.Results:Time to reach desired level T10 was quick in Group B compared to Group I. Regression of sensory and motor was prolonged in Group I compared to Group B. Total duration of analgesia was significantly prolonged in Group I 230.39 ± 16.20 compared to Group B 196.01 ± 14.32 and the difference is statistically significant (P = 0.0001). Both groups had Ramsay sedation score of 3 which lasted for 45 min in Group B while it was maintained in Group I. Side effects profile of both groups was comparable with few incidence of bradycardia and hypotension in both groups requiring treatment.Conclusions:We conclude that the continuous infusion of dexmedetomidine after SAB results in prolonged analgesia than just a bolus dose. Therefore, we suggest use of the maintenance dose of iv dexmedetomidine after SAB for prolonging the duration and achieving adequate sedation

Dexmedetomidine as an adjuvant for single spinal anesthesia in patients undergoing cesarean section: a system review and meta-analysis

“…Recently, dexmedetomidine has been commonly applied as an assistant drug for a subarachnoid block during the perioperative period. [37][38][39] A previous meta-analysis by Liu et al 15 considered that the addition of dexmedetomidine could significantly reduce the onset time of spinal anesthesia. However, two trials 14,20 in that metaanalysis did not meet the inclusion criteria because of the combined spinal and epidural anesthesia.…”

“…Recently, dexmedetomidine has been commonly applied as an assistant drug for a subarachnoid block during the perioperative period. 37–39 A previous meta-analysis by Liu et al. 15 considered that the addition of dexmedetomidine could significantly reduce the onset time of spinal anesthesia.…”

An observational study to compare the effect of intravenous dexmedetomidine versus intravenous magnesium sulphate pretreatment on characteristics of spinal anaesthesia

“…Which was statistically significant(P<0.001). Vatsalya et al 16 & Zhang H et al 17 concluded that administration of IV dexmedetomidine during subarachnoid block hastens onset of sensory & motor block. We observed statistically significant difference in duration of sensory block & prolongation in duration of motor blockage & time for two segment regression between group D & M (P<0.001).…”

The Effects of Premedication With Three Different Doses of Intravenous Dexmedetomidine on Spinal Anesthesia: A Randomized Comparative Study

“…Several clinical studies, including one meta-analysis, have reported the effects of intravenous dexmedetomidine (Dex) on subarachnoid block [2][3][4][5][6][7][8][9][10][11][12][13]. While some of the studies analyzed the effects of intravenous Dex by administering it first as a bolus followed by infusion [2][3][4][5][6][7], other studies analyzed it as either a bolus only [8][9][10] or as a continuous infusion only [12].…”

“…While some of the studies analyzed the effects of intravenous Dex by administering it first as a bolus followed by infusion [2][3][4][5][6][7], other studies analyzed it as either a bolus only [8][9][10] or as a continuous infusion only [12]. Besides, one study compared the bolus dose versus the infusion of Dex to evaluate the effects on the subarachnoid block [13].…”