Effect of supplementation of low dose intravenous dexmedetomidine on characteristics of spinal anaesthesia with hyperbaric bupivacaine

Abstract

Aims:Intravenous (IV) dexmedetomidine with excellent sedative properties has been shown to reduce analgesic requirements during general anaesthesia. A study was conducted to assess the effects of IV dexmedetomidine on sensory, motor, haemodynamic parameters and sedation during subarachnoid block (SAB).Methods:A total of 50 patients undergoing infraumbilical and lower limb surgeries under SAB were selected. Group D received IV dexmedetomidine 0.5 mcg/kg bolus over 10 min prior to SAB, followed by an infusion of 0.5 mcg/kg/h for the duration of the surgery. Group C received similar volume of normal saline infusion. Time for the onset of sensory and motor blockade, cephalad level of analgesia and duration of analgesia were noted. Sedation scores using Ramsay Sedation Score (RSS) and haemodynamic parameters were assessed.Results:Demographic parameters, duration and type of surgery were comparable. Onset of sensory block was 66±44.14 s in Group D compared with 129.6±102.4 s in Group C. The time for two segment regression was 111.52±30.9 min in Group D and 53.6±18.22 min in Group C and duration of analgesia was 222.8±123.4 min in Group D and 138.36±21.62 min in Group C. The duration of motor blockade was prolonged in Group D compared with Group C. There was clinically and statistically significant decrease in heart rate and blood pressures in Group D. The mean intraoperative RSS was higher in Group D.Conclusion:Administration of IV dexmedetomidine during SAB hastens the onset of sensory block and prolongs the duration of sensory and motor block with satisfactory arousable sedation.

Role of Intravenous Dexmedetomidine in Prolonging Postoperative Analgesia and Quality of Block Following Spinal Anaesthesia. A Systemic Review and Update

“…Dexmedetomidine is increasingly used as an adjunct to various regional techniques [3][4][5][6][7][8]. There are studies on its successful use to facilitate laryngoscopic endotracheal intubation without using muscle relaxant [9,10], and fiber optic guided intubation [11].…”

Comparison of the Dosage Regimes of Intravenous Dexmedetomidine to supplement Spinal Anesthesia with Hyperbaric Bupivacaine in Hysterectomy

“…7,9,15 Our observation of easy reversibility is supported by these workers. Harsoor et al 4 observed that hypotension did not warrant stoppage of infusion of Dex. The incidence of bradycardia was higher in group I (20%) than in group II (11.4%), but statistically it was not significant.…”

“…A ceiling effect for analgesia is reported at 0.5 µg/kg/hr of Dex. 4 Ok et al 13 have reported prolongation of sedation (Bispectral Index score 60-80) time with increasing maintenance doses (90 min for 0.2 and 120 min for 0.4 µg/kg/hr) following a bolus dose of Dex of 1 µg/ kg even for patients who receive final anesthesia with 13 mg bupivacaine. Duration of block and rescue analgesia was not studied in their report.…”

“…3 Intravenous Dex has been successfully used with bupivacaine SA in various dose regimes for urologic, lower limb, and gynecological surgery. [3][4][5] The IV route of Dex in comparison with oral or intrathecal routes gives flexibility of dose adjustment to control the degree of sedation precisely. This is very important as excess sedation is dangerous.…”

Study on evaluating the Adequacy of Psoas Compartment Block and Sacral Plexus Block for Lower Limb Surgeries

“…Dexmedetomidine, a highly specific centrally acting alfa-2 agonist, was used in our study for sedation, improving patient satisfaction and analgesia without causing respiratory depression. [18][19][20] In parasacral approach to sciatic nerve block, pudendal nerve would be blocked and there is a possibility of urinary retention. The incidence of urinary retention is <5% 6 in the literature.…”