Accelerated Recovery Following Opioid-free Anaesthesia in Supratentorial Craniotomy

Anaesthesia for craniotomy (open skull/brain) surgery focuses on maintaining blood supply to brain, avoiding factors that may lead to increased pressure in brain and aim for early neurological recovery. In recent decades, opioids have always been a mainstay for pain management and opioid-based anaesthesia (OBA). However, opioid use poses a significant number of adverse effects such as breathing depression, prolonged sedation, nausea and vomiting, itchiness, and many more. In view of this, recent studies on anaesthesia for craniotomy has noted a paradigm shift towards opioid-sparing or opioid-free anaesthesia (OFA) to prevent opioid-related adverse effects which might prolong patients' recovery. In order to guide anaesthesiologists' dosing of hypnotics and analgesics to provide appropriate depth of anaesthesia and adequate pain control, as well as to prevent under or overdosing, CONOX monitor is used during operation to measure depth of anaesthesia and painful stimulus.This clinical study will take place in neurosurgical operation theatres and neurosurgical intensive care unit (ICU) of University of Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia.

Inclusion CriteriaAdult patients who have supratentorial lesions going for elective craniotomies (age group- 18-65 years old)Patients with Glasgow Coma Scale of 15 (E4V5M6)Patients who are fit to give consentPower of elbow flexion of patient's dominant hand score 5 with Medical Research Council (MRC) Muscle scaleAmerican Society of Anaesthesiologists (ASA) Physical Status Classification I - III patientsExclusion CriteriaPatients who refused or not fit to consent for participationPatients with Glasgow Coma Scale less than 15Patients who have known allergy to the drugs used in this studyPatients on chronic opioid use (Chronic opioid use is defined as having any number of opioid prescriptions or dosing for at least 90 days continuously)Patients going for emergency craniotomies for supratentorial lesionsPatients who are not fit for extubation postoperativelyPatients with chronic kidney disease Stage 3A and above (eGFR less than 60 ml/min/1.73m2)Patients with known case of liver cirrhosis