Published: 2021-05-27

Comparison of two different doses of dexmedetomidine (0.25 mcg/kg and 0.5 mcg/kg) in prolonging duration of spinal anaesthesia and postoperative analgesia in patients undergoing trans urethral resection of prostate: a prospective randomized double blinded study

Anil K. Bhiwal, Karuna Sharma, Vikram S. Rathore, Chintan M. K. Patel, Alka Chhabra, Swai S. Jaitawat


Background: Trans urethral resection of prostate (TURP) under spinal anaesthesia (SAB) in elderly with associated cardio-pulmonary, endocrine or other co-morbidities induces detrimental physiological and psychological stress response to surgery and anaesthesia. Proper sedation during spinal anaesthesia can reduces this response. Aim of this study was to compare the characteristics of spinal block, hemodynamic changes, and postoperative analgesia, following administration of intravenous DMT (0.25 mcg/kg and 0.5 mcg/kg) in elderly patients undergoing TURP under SAB.

Methods: Sixty-eight patients were randomly allocated to two groups of 34 patients each. After giving spinal anaesthesia patients received two different doses of dexmedetomidine intravenously; 0.25 mcg/kg (Group D25) and 0.50 mcg/kg (Group D50) respectively. Drugs were given slowly in dilution of 10ml normal saline. Patients were monitored for intraoperative haemodynamics, sensory and motor block characteristics and postoperative analgesia in terms of VAS (visual analogue scale) and first and total dose of rescue analgesic.

Results: Mean value of lowest HR in Group D50 and D 25 was comparable (p=0.11) and time taken to achieve lowest HR was also comparable (p=0.13). Mean value of lowest SBP, DBP and MAP were lower in Group D50 than in Group D25 but the difference did not reach statistical significance (p=0.52,0.95 and 0.41 respectively). Onset of sensory block was comparable between the two groups, p=0.62. Maximum sensory block was achieved significantly earlier in Group D50 (10.64±2.75 min versus 12.94±3.04 min in Group D25), p=0.0012. Group D50 patients achieved Bromage score 3 earlier (10.735±1.797 min) than group D25 (12.794±2.52 min) (p=0.00). Recovery from motor block was found earlier in Group D25 group (141.325±4.97 mins) compared to Group D50 (154.41±8.143 mins). Group D50 reported significantly higher sedation than group D25 (p=0.00). Group D25 reported more pain at 4 hours compared to Group D50 (VAS -4.705±0.462 versus 2.588±1.478). Time of requirement of first rescue analgesia was delayed in Group D50 (270.59±50.78 mins) than in Group D25 (172.50±10.46 mins), p=0.000.

Conclusions: Dexmedetomidine is effective in relieving anxiety in elderly patients undergoing TURP under spinal anaesthesia. Dose of 0.50 mcg/kg is more effective than 0.25 mcg/kg without increasing the risk of adverse effect.



TURP, Spinal anaesthesia, Sedation, Dexmedetomidine

Full Text:



Hong JY, Yang SC, Ahn S, Kil HK. Preoperative comorbidities and relationship of comorbidities with postoperative complication in patients undergoing transurethral prostate resection. J Urol. 2011;185:1374-8.

Kim SY, Cho JE, Hong JY, Koo BN, Kim JM, Kil HK. Coparison of intrathecal fentanyl and sufentanyl in low-dose dilute bupivacaine spinal anesthesia for transurethral prostatectomy. Br J Anaesth. 2009;103:750-4.

Ben-david B, Solomon E, Levin H, Admoni H, Goldik Z. Intrathecal fentanyl with small-dose dilute bupivacaine: better anesthesia without prlonging recovery. Anesth Analg. 1997;85:560-5.

Kararmaz A, Kaya S, Turhanogle S, Ozyilmaz MA. Low dose bupivacaine-fentanyl spinal anesthesia for transurethral prostatectomy. Anesthesia. 2013;58:526-30.

Eisenach JC, De Kock, Klimscha W. Alpha-2 adrenergic agonists for regional anesthesia. A clinical review of clonidine. Anesthesiology. 1996;85:655-74.

Dobrydnjov I, Axelsson K, Thorn SE, Mathhiesen P, Klochhoff H, Holmstrom B, Gupta A. Clonicine combined with small dose bupivacaine during spinal anesthesia for inguinal herniorrhaphy: a randomized double blinded study. Anesth. Analg. 2003;96:1496-503.

Strebel S, Gurzeler JA, Schneider MC, Aeschbach A, Kindler CH. Small dose intrathecal clonidine and isobaric bupivacaine for orthopedic surgery: a dose-response study. Anesth Analg. 2004;99:1231-8.

Elia N, Culebras X, Mazza C, Schiffer E, Tramer MR. Clonicdine as an adjuvant to intrathecal local anesthetics for surgery: systematic review randomized trials. Reg Anesth Pain Med. 2008;33:159-67.

American Society of Anesthesiologists Task Force on Sedation and Analgesia by Non-Anesthesiologists. Practice guidelines for sedation and analgesia by non-anesthesiologists. Anesthesiology. 2002;96:1004-17.

De Andres J, Valia JC, Gil A, Bolinches R. Predictors of patient satisfaction with regional anesthesia. Reg Anesth. 1995;20:498-505.

Kim J, Kim WO, Kim H, Kil HK. Adequate sedation with single-dose Dexmedetomidine in patient undergoing Transurethral Resesction of prostate with spinal anaesthesia: a dose- response study by age group. BMC Anesthesiology. 2015;15(17):01-5.

Upadhyay SP, Samanth U, Tellicherry S, Mallick P. Role of Intravenous Dexmedetomidine in prolonging postoperative Analgesia and Quality of Block Following Spinal Anesthesia. A Systemic Review and Update. J pain Releif. 2015; 4(2):01-6.

Kim JE, Kim NY, Lee HS, Kil HK. Effect of Intrathecal Dexmedetomidine on Low-Dose Bupivacaine Spinal Anesthesia in Elderly Patient Undergoing Transurethral Prostatectomy. Biol Pharm Bull. 2013;36(6):959-65.

Harsoor SS, Nethra SS, Rani DD, Sudheesh K, Yalamuru B. Effect of supplementation of low dose intravenous dexmedetomidine on characteristic of spinal anesthesia with hyperbaric bupivacaine. Indian Journal of Anesthesia.2013;57(3):256-9.

Jung SH, Lee SK, Lim KJ, Park EY, Kang MH. The effects of single dose intravenous dexmedetomidine on hyperbaric bupivacaine spinal anesthesia. J Anesth. 2013;27:380-4.

Hamed A, Talaat S. Effect of intravenous versus intrathecal low-dose dexmedetomidine on spinal block in lower limb orthopedic surgery. Ain-Shams Journal of Anesthesiology. 2014;7:205-10.

Sharma S, Somani M, Chandramohan M, Raiger LK. Evaluating the effects of dexmedetomidine premedication on the quality of subarachnoid block, haemodynamics and sedation in patients undergoing lower limb surgeries: a prospective randomized controlled trial. International Journal of Research in Medical Sciences. 2017;5(12):5410-7.

Kubre J, Sethi A, Mahobia M,Bindal D, Narang N, Saxena A. Single dose intravenous dexmedetomidine prolongs spinal anesthesia with hyperbaric bupivacaine. Anesth Essays Res. 2016;10:273-7.

More P, Pol J, Laheri V. A prospective, randomized controlled study of intravenous dexmedetomidine on 0.5% hyperbaric bupivacaine used in spinal anesthesia. Medico Research Chronicles. 2017;4(1);158-68.

Annamalai A, Singh S, Singh A, Mahrous DE. Can Intravenous Dexmedetomidine Prolong Bupivacaine Intrathecal Spinal Anesthesia. J. Anesth Clin Res. 2013;4(12):01-5.

Abdallah FW, Abrishami A,Brull R. The facilitatory effects of intravenous dexmedetomidine on the duration of spinal anesthesia:A systemic review and meta-analysis. International Anesthesia Research Society. 2013;116:01-8.

Lee MH, Ko JH, Kim EM, Cheung MH, Choi YR, Choi EM. The effects of intravenous dexmedetomidine on spinal anesthesia: comparison of different dose of dexmedetomidine. The Korean Society of Anesthesiologist. 2014;67(4):252-7.

Lugo VW, Gomez IA, Cisneros-Corral R, Martinez-Gallegos N. Intavenous, dexmedetomidine versus intravenous clonidine to prolong bupivacaine spinal anaesthesia. A double blind study. Anestesia en Mexico. 2007;19:143-6.

Kaya FN, Yavascaoglu B, Turker G, Yildirim A, Gurbet A, Mogol EB, Ozean B. Intravenous dexmedetomidine, but not midazolam, prolongs bupivacaine spinal anesthesia. Canadian Journal of Anesthesiology. 2010;57:39-45

Dinesh CN, Sai Tej NA, Yatish B, Pujari VS, Mohan VR. Effects of intravenous dexmedetomidine on hyperbaric bupivacaine in spinal anesthesia. SJA. 2014;8(2):202-8.

Reddy VS, Shaik NA, Donthu B, Reddy Sannala VK, Jangam V. Intravenous dexmedetomidine versus clonicine for prolongation of bupivacaine spinal anesthesia and analgesia: A randomized double-blind study. J Anaesthesiol Clin Pharmacol. 2013;29:342-7.