Comparative Efficacy of Addition of Fentanyl and Neostigmine to Isobaric 0.75% Ropivacaine in Elderly Patients undergoing Transurethral Resection of Prostate under Spinal Anaesthesia: A Double-blinded Randomised Clinical Study

Abstract

Introduction: Ropivacaine is a well-accepted local anaesthetic drug used in spinal and peripheral nerve blocks.It provides a better central nervous system and cardiovascular stability in comparison to bupivacaine. Adjuvants are also added with these drugs as they provide haemodynamic stability, increase efficacy, and decrease the dose requirement of the local anaesthetic drugs. Aim: To determine the efficacy of isobaric 0.75% ropivacaine in combination with normal saline, fentanyl, and neostigmine in Elderly Patients Undergoing Transurethral Resection of Prostate Under Spinal Anaesthesia. Materials and Methods: This double-blinded randomised clinical study conducted in the Department of Anaesthesiology and Critical Care, Institute of Medical Sciences-Banaras Hindu University, Varanasi, Uttar Pradesh, India, from July 2018 to June 2019. The study included 90 patients who were divided into three groups of 30 subjects each. Ropivacaine combined with normal saline in group RNS, ropivacaine combined with fentanyl in group RFE and ropivacaine combined with neostigmine in group RNE, was administered intrathecally.Heart rate, respiratory rate, blood pressure, onset and duration of sensory and motor block, along with the duration of analgesia, were recorded at different time points. The Analysis Of Variance (ANOVA) was used to compare the variables among the three study groups, and Student-Newman-Keuls was used to compare the data between the groups. Results: Patients in group RNE showed a significant fall in heart rate in comparison to groups RNS and RFE at all the time points. Respiratory rate followed a similar pattern in group RNE (p-value <0.001), except at 5 min and 90 min. Mean systolic blood pressure showed a significant rise in group RNE compared to the other two groups, while diastolic blood pressure followed a similar trend at 10, 20, 30, and 60 min. The SpO2 (%) was comparable among groups. The onset of sensory loss was significantly earlier in group RNE (239.6±28.8 sec) than in groups RNS (298.1±27.8 sec), and RFE (261.9±32.2 sec). The duration of the sensory block was significantly longer in group RFE (227.8±30.5 min). The mean time to the onset of motor block (480.7±30.2 sec) and analgesia (582.33±30.2 min) was longer in group RNE than in other groups. Conclusion: The addition of neostigmine to ropivacaine intrathecally is a reliable method to prolong spinal anaesthesia but close monitoring of vitals is desirable.