Impact of Sub-Anesthetic Dose of Ketamine on Post Spinal Hypotension in Cesarean Delivery

Abstract Background Spinal anesthesia is the commonest technique used in Cesarean Section (CS) and most frequently associated with maternal hypotension, for whicha lot of techniques have been described to prevent but an effective method is yet to be found. Objectives The aim was to study the effect of using a sub-anesthetic dose of ketamine to prevent post-spinal hypotension in CS delivery. Methods This double-blinded randomized controlled study was conducted on 60 participating parturients who were ASA І, П term pregnant. All the parturients received spinal anesthesia. The parturients were then randomly divided into two equal groups (n = 30 in each); ketamine group received a sub- anesthetic dose of ketamine of 0.5 mg/kg IV bolus in 3 ml saline and control group received the same volume of normal saline IV bolus. Heart Rate (HR) and Mean Arterial blood Pressure (MAP) were recorded at baseline (5 minutes prior to the intrathecal injection), at 5, 10, 15 and 20 minutes after the injection and then every 15 minutes till the end of the operation. Incidences of hypotension and severe hypotension were recorded. The total dose of ephedrine was recorded. Modified Ramsay sedation score was recorded at baseline then 5, 10, 15, 30, 45 minutes after injection and then at the end of the operation. Results The study revealed that ketamine didn’t prevent hypotension, it only delayed it for 10 min compared to control group 5 min. Also, observed that total ephidren dose significantly decreased in ketamine group compared to control group. And sedation scores in the first 30 min were higher in ketamine group. HR wasn’t affected. No changes in APGAR score were noticed between the two groups. No side effects from ketamine except for nystagmus. Conclusion This study concluded that the use of intravenous ketamine in low dose (0.5mg/kg) doesn’t prevent postspinal hypotension but it only decreases ephidren requirements.