title: A randomised controlled trial comparing the effect of adjuvant intrathecal 2 mg midazolam to 20 micrograms fentanyl on postoperative pain for patients undergoing lower limb orthopaedic surgery under spinal anaesthesia.
abstract: BACKGROUND
  Intrathecal adjuvants are added to local anaesthetics to improve the quality of neuraxial blockade and prolong the duration of analgesia during spinal anaesthesia. Used intrathecally, fentanyl improves the quality of spinal blockade as compared to plain bupivacaine and confers a short duration of post-operative analgesia. Intrathecal midazolam as an adjuvant has been used and shown to improve the quality of spinal anaesthesia and prolong the duration of post-operative analgesia. No studies have been done comparing intrathecal fentanyl with bupivacaine and intrathecal 2 mg midazolam with bupivacaine.
  
  
  OBJECTIVE
  To compare the effect of intrathecal 2mg midazolam to intrathecal 20 micrograms fentanyl when added to 2.6 ml of 0.5% hyperbaric bupivacaine, on post-operative pain, in patients undergoing lower limb orthopaedic surgery under spinal anaesthesia.
  
  
  METHODS
  A total of 40 patients undergoing lower limb orthopaedic surgery under spinal anaesthesia were randomized to two groups. Group 1: 2.6mls 0.5% hyperbaric bupivacaine with 0.4mls (20micrograms) fentanyl Group 2: 2.6mls of 0.5% hyperbaric bupivacaine with 0.4mls (2mg) midazolam.
  
  
  RESULTS
  The duration of effective analgesia was longer in the midazolam group (384.05 minutes) as compared to the fentanyl group (342.6 minutes). There was no significant difference (P 0.4047). The time to onset was significantly longer in midazolam group 17.1 minutes as compared to the fentanyl group 13.2 minutes (P 0.023). The visual analogue score at rescue was significantly lower in the midazolam group (5.55) as compared to the fentanyl group 6.35 (P - 0.043).
  
  
  CONCLUSIONS
  On the basis of the results of this study, there was no significant difference in the duration of effective analgesia between adjuvant intrathecal 2 mg midazolam as compared to intrathecal 20 micrograms fentanyl for patients undergoing lower limb orthopaedic surgery.
authors.affiliation: Department of Anaesthesia, Aga Khan University, East Africa.
authors.forename: Francis
authors.initials: F
authors.lastname: Codero
authors.affiliation: Department of Anaesthesia, Aga Khan University, East Africa.
authors.forename: Mung'ayi
authors.initials: M
authors.lastname: Vitalis
authors.affiliation: Department of Anaesthesia, Aga Khan University, East Africa.
authors.forename: Sharif
authors.initials: S
authors.lastname: Thikra
mesh_terms: D000328:Adult; D000775:Anesthesia, Spinal / Q000379:methods*; D018686:Anesthetics, Intravenous / Q000008:administration & dosage / Q000627:therapeutic use*; D002045:Bupivacaine / Q000627:therapeutic use; D005260:Female; D005283:Fentanyl / Q000627:therapeutic use; D006801:Humans; D035002:Lower Extremity / Q000601:surgery*; D008297:Male; D008874:Midazolam / Q000627:therapeutic use; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000379:methods*; D010149:Postoperative Pain / Q000188:drug therapy*; D011183:Postoperative Complications / Q000453:epidemiology; D011446:Prospective Studies; D016037:Single-Blind Method
chemical_list: D018686:Anesthetics, Intravenous; D008874:Midazolam; D005283:Fentanyl; D002045:Bupivacaine
keywords: Midazolam fentanyl; lower limb; orthopaedic surgery; spinal anaesthesia