COMPARISON BETWEEN PROPOFOL AND MIDAZOLAM FOR AROUSAL TIME IN INFRAUMBILICAL SURGERIES REQUIRING SPINAL ANAESTHESIA.
Abstract
Introduction: The use of spinal anesthesia is often limited by the unwillingness of patients to remain awake during surgery. Intravenous sedative medications are useful as positioning for surgery can be uncomfortable and spontaneous movements by an inadequately sedated patient can cause interference with the surgical procedure. Over sedation may compromise the safety of the patient. Also it is not always possible to predict precisely how an individual patient will respond to a particular dose. Over sedation may be associated with deleterious effects of respiratory and cardiovascular depression which results in airway instrumentation and hypotension leading to a prolonged stay in the post-anaesthetic care unit. Bispectral index (BIS) monitoring may be helpful when over sedation has to be avoided as clinical scales do not allow a discrimination of deep sedation.
Material and Methods: A total of 100 patients 50 in each groups were randomly selected and were included in the study. Patients posted for elective infraumbilical operations were included. Weight and height of all patients were noted during the pre-anaesthetic check-up also BMI was calculated. They were also given a demonstration about the use of the 7-point Likert-like verbal rating scale to express their satisfaction about the quality of sedation they would receive during the intra-operative period. In operation theatre blood pressure, electrocardiogram, pulse oximeter was attached to the patient and mean arterial pressure [MAP], heart rate [HR] and peripheral arterial oxygen saturation [SpO2]) were recorded. Spinal anaesthesia was given in the left lateral decubitus position. Injection propofol or injection midazolam was injected through infusion pump as per the study group.
Results: A total of 100 patients were included in the study of which 50 were in the propofol group and 50 were in the midazolam group. No significant difference in propofol and midazolam group was observed in respect to age, sex, BMI, height and weight. The intra-operative parameters (MAP and HR) and the peripheral oxygen saturation (SPO2) were compared at various time points. The MAP and the HR were lower in the Group P than in Group M, but the intra-group MAP and HR in both the groups were stable throughout. The MAP and HR in both the group showed no significant differences in both the group. Also in SPO2 no difference was observed. The mean arousal time from sedation with BIS score 90 with injection propofol was 8.23±2.94 min, whereas, with injection midazolam it was 16.22 ±3.17min, p value < 0.0001 the difference was statistically significant. The time taken to reach an OAA score of 5 was 7.54± 1.98 min with propofol versus 14.59± 3.24 min with midazolam.
Conclusion: A shorter arousal time from sedation during spinal anaesthesia can be achieved using propofol compared with midazolam. Midazolam and propofol are effective sedative agents but the time to reach effective sedation was less with propofol than midazolam and time to recovery time from sedation was lesser with propofol.
Keywords: SPO2, MAP, HR, hypnosis stage, areflexiastage and CNS.
