Role and efficacy of intrathecal bupivacaine (0.5) with the multiple doses of midazolam (1 mg to 2 mg) while lower limb surgeries

Abstract

Background: Spinal anaesthesia, which is one of the techniques for infraumbilical surgeries, is most commonly criticized for limited duration of postoperative analgesia. Discovery of spinal receptors like alpha 2 adrenergic, cholinergic, opioid, NMDA and gamma aminobutyric acid (GABA) and benzodiazepine receptors trigger the use of drugs like neostigmine, clonidine, opioids ketamine, midazolam for their synergistic effect with intrathecal local Anaesthetics. Materials and methods: It was a double blind, prospective, randomised study patients with ASA 1 and 2 was taken. Exclusion criteria were patients with cardiac problem, respiratory problem, coagulation disorders, mental disorders and contraindication to regional block. Day before surgery preanesthetic evaluation was carried and procedure was explain to each patient. 0.5 mg alprazolam and ranitidine 150 mg given bedtime the night before surgery patient is kept NPO overnight. Results: In our study duration of motor block in group 1 and group 2 was 3.22 (hr) ± 0.73 & 3.52±0.77 P value 0.226. Duration of sensory block in group 1 and group 2 was 4.09 (hr) ± 0.88 & 6.69 (hr) ± 1.29 p-value<0.001 significant. There is higher duration of pain free period with group 2. So we can say that intrathecal 2mg Midazo lam added to bupivacaine, duration of postoperative analgesia was significantly prolonged than 1 mg midazolam. Conclusion: The duration of effective analgesia when midazolam is added to intrathecal bupivacaine is significantly prolonged thereby proving that midazolam is a useful adjunct to intrathecal bupivacaine for post-operative analgesia. Effect of intrathecal midazolam is dose dependent 2mg midazolam prolongs the action of bupivacaine with good sedation and no unwanted side effects.