Vol 14, Issue 9, 2021 Online - 2455-3891 Print - 0974-2441 COMPARISON OF INTRATHECAL HYPERBARIC ROPIVACAINE 0.5% WITH AND WITHOUT 75 MG MAGNESIUM SULFATE AS AN ADJUVANT FOR INFRA UMBILICAL SURGERIES: A DOUBLE-BLIND RANDOMIZED CLINICAL TRIAL SRINIDHI SRIKANTH, ANTONY JOHN CHARLES S*, YASHA KAMAESHAR, GAYATRI MISHRA Department of Anaesthesiology, Mahatma Gandhi Medical College and Research Institute, Sri Balaji Vidyapeeth Deemed to be University, Pillayarkuppam, Puducherry, India. Email: anjocharlie@gmail.com Received: 20 June 2021, Revised and Accepted: 03 August 2021 ABSTRACT Objective: Intrathecal magnesium as an adjuvant to hyperbaric ropivacaine could extend duration of sensory blockade and improve the quality of post-operative analgesia; thereby reducing opioid requirements and its adverse effects. Hence, we conducted this prospective, randomized, double- blind clinical trial to observe its effects for day care surgeries. Methods: After obtaining institutional ethical committee approval and registration of trial, patients’ informed consent was taken and eighty adult patients of either gender, ASA 1 and 2, posted for infra umbilical surgeries were divided into two groups: Group RM received 3 ml hyperbaric Ropivacaine with 0.75 ml magnesium sulfate (75 mg) and Group R received 3 ml hyperbaric Ropivacaine with 0.75 ml sterile water. Sensory and motor blockade parameters, hemodynamic variables, and adverse effects were monitored, analyzed using appropriate statistical tests. Results: Total duration of sensory blockade was significantly prolonged in Group RM compared to Group R (242.8 ± 9.9 versus 186.6 ± 8.4 min) (***p<0.001). Complete motor regression was observed significantly earlier in Group RM than in Group R (151.3 ± 7.8 versus 184.7 ± 5.6 min) (*p<0.05). Post-operative pain free interval was significantly prolonged in group RM compared to group R (725.2 ± 18.6 vs. 515.2 ± 17.8 min) (***p<0.001). Conclusion: We concluded that intrathecal magnesium as an adjuvant to hyperbaric Ropivacaine significantly prolonged both sensory blockade duration, post-operative pain-free interval without increasing motor blockade duration and the incidence of adverse effects. Keywords: Intrathecal magnesium sulfate, Intrathecal hyperbaric ropivacaine, Day care anesthesia. INTRODUCTION Spinal anesthesia is a preferred technique for day-care orthopedic, gynecological, and lower abdominal surgical procedures [1]. Lignocaine was commonly used due to its short duration of action but reports of transient radicular irritation led to decline in its use [2]. Intrathecal Ropivacaine offers shorter motor blockade duration hence, encouraging early mobilization in patients [3-5]. Due to difficulty in maintaining pharmacological stability of hyperbaric Ropivacaine, presently only isobaric solution is available. But Ropivacaine, made hyperbaric with Dextrose, had produced more consistent block, prolonged the needed duration with quicker complete regression [6,7]. Opioid adjuvants have been used with intrathecal Ropivacaine for extending the duration of block and their side effects such as nausea, vomiting, pruritus, and sedation have been noted [8,9]. Intrathecal magnesium has been used in humans since 1906 [10,11]. Comparison of hyperbaric Ropivacaine, which is emerging as local anesthetic of choice for spinal anesthesia in day care surgery [2] with and without magnesium sulfate alone; is elucidated in fewer studies. Hence, we conducted this randomized trial to demonstrate its effects as an adjuvant to intrathecal hyperbaric Ropivacaine for day care infra umbilical surgeries by monitoring block characteristics, hemodynamic parameters, and adverse effects. METHODS This present prospective, randomized, and double-blind clinical trial was conducted in a tertiary care teaching hospital from January 2019 to June 2020 after obtaining Institutional Ethics Committee approval and registration in Clinical Trials Registry of India. 80 adult patients (18–60 years) of either gender, American Society of Anesthesiologists Grade 1 and 2, posted for infra umbilical procedures under orthopedics, gynecology, urological, and general surgeries of approximately 2-h duration were included in the study. Patients unwilling to participate, pregnant and breast-feeding mothers, patients with spinal deformity, instrumentation or any contraindications for spinal anesthesia and patients with major cardiac, neurological, and respiratory illness were excluded from the study. Selected patients underwent pre-anesthetic checkup and were informed about the aim of our study, familiarized with visual analogue scale (VAS) (0 – no pain to 10 – worst ever imaginable pain) in their local language, and a written informed consent was taken after ensuring their willingness to participate in the study. Patients were kept Nil by mouth from 10 pm the day before surgery. Tablet Ranitidine 150 mg, Tablet Metoclopromide 10 mg, and Tablet Alprazolam 0.25 mg were given with sips of water on the night before and at 7 am on the morning of surgery. After taking patient inside the operation theatre, monitors were attached and baseline electrocardiogram, blood pressure, and SpO2 were noted. A wide bore intravenous (IV) line was secured with 18Gauge (G) IV cannula, and the fluid Ringer lactate infused at the rate of 10 ml/kg/h. Patients were selected through simple random sampling using computer generated numbers and group allocation was done through sealed envelope technique. Patients were divided into two groups: © 2021 The Authors. Published by Innovare Academic Sciences Pvt Ltd. This is an open access article under the CC BY license (http://creativecommons.org/ licenses/by/4.0/) DOI: http://dx.doi.org/10.22159/ajpcr.2021v14i9.42497. Journal homepage: https://innovareacademics.in/journals/index.php/ajpcr Research Article