Comparative Efficacy and Safety of Propofol-Ketamine Combination Versus Propofol Monotherapy in Geriatric Patients Under Invasive Ventilation

The study is a prospective randomized controlled trial comparing the efficacy and safety of propofol-ketamine ("Ketofol") versus propofol monotherapy in geriatric ICU patients. Eligible participants are critically ill elderly patients with a history of cardiac disease who require endotracheal intubation and have not yet received sedation. The investigators focus on a specific population in which geriatric patients have different pharmacokinetics and pharmacodynamics and are more prone to side effects than other populations. Primary outcome: Incidence of hemodynamic instability (defined as hypotension requiring vasopressors), measured by mean arterial pressure (MAP) at baseline, during intubation, and post-intubation at 1, 5, 10, 30, and then every 8h for 24 hours.