Time to emergence and factors affecting emergence in patinets with aneurysmal subarachnoid hemorrhage following craniotomy: A prospective observational study

Introduction: Rapid emergence is deemed necessary in the patients undergoing neurosurgery in order to permit an early neurological evaluation. The incidence of the early extubation in neurosurgical patients who underwent intracranial surgery has been around 82-89%. However, the pattern of emergence in patients undergoing neurosurgery following an acute aneurysmal sub-arachnoid hemorrhage has not yet been reported. Methods: The study is a prospective observational study conducted over a period of one and a half years. All the pre-operative (age, gender, weight, ASA, Hunt and Hess, WFNS, Fisher) and intra-operative data (Total anesthetic time, total surgical time, estimated total intraoperative blood loss, amount of intravenous fluids, urine output, temporary clipping time, IOR, temperature at the end of the surgery (≤36 or >36°C), anesthetic drugs, brain bulge) data was recorded and analysed to assess the factors effecting emergence in the pateints undergoing clipping. Results: A total of 67 patients, aged 46 years [IQR - 40-53], 33 male and 34 female were included in the study. 44, 16 and 2 patients were of WFNS grade I, II and III at the time of the admission respectively. The number of the pateints with admission CT Fisher grade I, II, III and IV were 6, 20, 25 and 16 respectively. At the time of the surgery 1 patient had GCS of 13 while 6 and 60 patients had a GCS of 14 and 15 respectively. The median time to emergence was 17 minutes (IQR 10-240 minutes). On univariate analysis the factors which were found to have significant co-relation with time to emergence were pre-operative GCS (p = 0.002, WFNS grade (p = 0.005, TC duration (p = 0.03) and the temperature at the end of the surgery (p = 0.00, In generalized linear model (γ- distribution), the temperature at the end of the surgery (p = 0.0.00), temporary clipping duration (p = 0.008), ASA grade (p = 0.05), Fischer grade (p = 0.002), duration of anaesthesia (p = 0.042) and GCS pre-induction (p = 0.00) had significant impact on the emergence time in pateints undergoing clipping for ruptured aneurysm. Conclusion: None of the pre-operative and intra-operative factors had any significant effect on the time to emergence. Of all the factors GCS and temperature at the end of the surgery had the maximum impact on the time to emergence in pateints undergoing clipping for ruptured aneurysms.