Aneurysmal subarachnoid hemorrhage (SAH) is a neurosurgical emergency. Surgical clipping and endovascular coiling are the preferred treatment options. The anesthetic goals include smooth induction and emergence, with blood pressure control, control of intracranial pressure (ICP), intraoperative brain swelling, and maintenance of adequate cerebral perfusion pressure (CPP).Propofol is an induction agent, it decreases cerebral blood flow (CBF) and maintains flow-metabolism coupling. However, systemic vasodilatory effects of propofol can cause a decrease in blood pressure. In contrast, ketamine, a phencyclidine derivative, increases cerebral metabolic rate and CBF and has strong sympathomimetic activity. For these reasons, it has been infrequently used during neurosurgical cases. However, sympathomimetic actions of ketamine increase mean arterial pressure (MAP) and possibly increase CPP which can prevent secondary brain injury. Etomidate is an anesthetic agent that has minimal effect on circulation. It can effectively maintain hemodynamics and effect on heart rate and blood pressure is much lower than that of other anesthetic drugs, which can reduce the probability of arrhythmias and other phenomena in patients. Alongside it can reduce the incidence of postoperative cognitive dysfunction and can also shorten postoperative hospital stays. The addition of ketamine to etomidate could have a synergistic effect on the neurocognitive outcome of patients with stable hemodynamics intraoperatively.

Optic nerve sheath diameter (ONSD) is a simple, safe, inexpensive, and bedside diagnostic tool to monitor intracranial pressure non-invasively. An increase in ICP causes enlargement of the ONSD, which can be measured indirectly using an ultrasound.

Through this trial, we would like to compare ketomidate with ketofol among patients with cerebral aneurysms undergoing clipping surgery. To the best of our knowledge and literature search, no randomized controlled trial has compared the effect between the above-mentioned drugs. We hypothesized that ketomidate would be non-inferior to ketofol in decreasing ICP and maintaining stable hemodynamics without compromising brain relaxation.. We hypothesized that Ketomidate would be non-inferior to ketofol in decreasing ICP and maintaining stable hemodynamics without compromising brain relaxation.We hypothesized that Ketomidate would be non-inferior to ketofol in decreasing ICP and maintaining stable hemodynamics without compromising brain relaxation.After clearance from the institutional ethical committee (IEC), registering in CTRI, and obtaining written informed consent, 46 patients will be randomized into two study groups based on a computer-generated random number. The group allocation will be concealed by keeping the numbers in sealed opaque envelopes that will be opened just before shifting the patient to the operation room (OR).Patients will be shifted into the OR and standard American Society of Anesthesiologists (ASA) monitoring like electrocardiogram (ECG), non-invasive blood pressure (NIBP), pulse oximetry (SPO2) and temperature will be initiated. An intravenous (IV) line will be secured and 0.9% normal saline will be started. General anesthesia induction will be done with an IV injection of fentanyl 2mcg/ kg and injection of lignocaine 1.5 mg/kg followed by the study drug in titration till loss of verbal response as per group allocation.

Group KM: IV injection Ketomidate (1:5 of Ketamine: Etomidate) will be used for induction in titration.

Group KF: IV injection of Ketofol (1:5 of Ketamine: Propofol) will be used for induction in titration.