454 IJSR - INTERNATIONAL JOURNAL OF SCIENTIFIC RESEARCH Volume : 2 | Issue : 12 | December 2013 • ISSN No 2277 - 8179 Research Paper Medical Science Dr. Keshav Govind Rao Assistant Professor, Department of Anaesthesiology, Integral Institute of Medical Sciences and Research, Lucknow Dr Manoj Kumar Chaurasiya Assistant Professor, Department of Anaesthesiology, Integral Institute of Medical Sciences and Research, Lucknow Dr Pawan Kapoor Assistant Professor, Department of Anaesthesiology, Integral Institute of Medical Sciences and Research, Lucknow Dr Aparna Shukla Professor, Department of Anaesthesiology, Integral Institute of Medical Sciences and Research, Lucknow ABSTRACT Objective- This study was designed to compare the effect of two doses of dexmedetomidine [5mcg and 10 mcg] on onset and duration of sensory and motor block of hyperbaric bupivacaine when given intrathecally. Methods- Study was conducted in 52 ASA I/II patients posted for lower abdominal surgeries under subarachnoid block. Patients were divided in two groups of 26 patients each. Group 1 and group 2patients received 5mcg and 10 mcg dexmedetomidine respectively with 12.5 mg bupivacaine heavy intrathecally. Onset and duration of sensory and motor block was assessed. Result- Dexmedetomidine reduced onset and prolonged the duration of sensory and motor block of hyperbaric bupivacaine .No signifi- cant side effect or haemodynamic instability noted in either group. Conclusion- Dexmedetomidine is good alternative as an adjuvant to intrathecal bupivacaine in surgical procedures that require long time with minimal side effects. A Randomized Controlled Double Blind Study to Compare Dexmedetomidine 5 µg and 10 µg as an Adjuvant to Intrathecal Bupivacaine KEYWORDS : Dexmedetomidine, in- trathecal, Bromage. INTRODUCTION Over the last few decades there has been drastic improvement in the regional anesthetic techniques. Use of intrathecal adjuvant has gained popularity in recent years. Extensive experimenta- tion is going on in this field with the aim of prolonging duration of sensory block providing better postoperative analgesia with minimal side effects. Dexmedetomidine is highly selective α 2 agonist. Based on earlier studied, it is hypothesized that when dexmedetomidine is added to intrathecal bupivacaine, the dura- tion of sensory and motor block is prolonged. [1,2] This study was carried out to evaluate and compare the effect of two doses of dexmedetomidine (5µg. and 10µg) on onset and duration of sensory and motor block of hyperbaric bupivacaine. Material and METHOD This prospective randomized double blind study was carried out in 52 patients posted for lower abdominal surgery under subarachnoid block at the Department of Anaesthesiology, Inte- gral Institute of Medical Sciences and Research, Lucknow after taking approval from the institutional ethical committee. Patients were informed about the drug used and procedure and written, informed consent were taken from all. ASA grade I and II patients between the age group of 20-60 years were included in the study. Exclusion criteria were ASA grade III, IV, V patients, patient with any significant medical condition and pregnant pa- tients. Patients were randomly allocated into two groups of 26 patients in each group. Group I patients received 12.5 mg 0.5% bupiv- acaine heavy with 5 µg dexmedetomidine and group II patients received 12.5 mg 0.5% bupivacaine heavy with 10 µg dexme- detomidine. Normal saline was added to make total volume of drug to 3 ml. Patients were kept nil by mouth for 12 hours. On the day of sur- gery the patients were wheeled into operation theatre and all baseline parameters i.e. HR, NIBP, ECG recorded. All patients were premedicated with injection Ranitidine IV and Injection Ondansetron 8 mg IV. Preloading was done with Ringer lactate (15 ml/kg). Haemodynamic parameters were recorded after every 5 minutes for the first 15 minutes, then after every 15 minutes till three hours and then three hourly for the next 24 hours.. Subarchnoid block was given in sitting position at L3-L4 level and desired drug was given. The sensory dermatome level was assessed by cold sensation using an alcohol swab along the mid-clavicular line bilaterally. The motor dermatome level was assessed according to the mod- ified Bromage scale: 0-the patient is able to move the hip, 1-the patient is unable to move the hip but able to move the knee and ankle, 2- the patient is unable to move the hip & knee but is able to move the ankle, 3- the patient is unable to move the hip, knee and ankle [3]. The sensory level and Bromage scale were re- corded every two minutes after the spinal injection upto the 10 th minute and after that every 3 minutes until the highest dermat- ome was reached. All the durations were calculated considering the time of spinal injection as time zero. When the sensory level of anesthesia was not equal bilaterally, the higher level was used for statistical analysis. The patients were discharged after sen- sory regression to the S1 segment and Bromage scale of 0. The hypotension was defined as systolic blood pressure <90 mmHg and Bradycardia was defined as heart rate <50 beats/minute. Hypotension was treated by Injection Ephedrine (in aliquots of 6mg) and bradycardia was treated by Inj. Atropine 0.6 mg i.v. Statistical Analysis The results were presented in percentages and mean±SD. The dichotomous/categorical variables were compared by using Chi-square test. Unpaired t-test was used to compare the con- tinuous variables between the groups. The p-value<0.05 was considered as significant. All the analysis was carried out by us- ing SPSS 16.0 version. RESULTS Patients were comparable to each other in the terms of demo- graphic profiles (Table 1). The onset of sensory block (i.e. time taken to reach up T10 der- matome) was earlier in group II (3.9±1.5 min.) as compared to group I (6.9±1.7 min.) The difference was statistically signifi- cant (Table 2). The onset of motor block was also significantly earlier in group II as compared to group I (9.1±2.5 Vs. 12.88 ± 3.1 min). There was more time taken in regression of sensory block to