A Comparative Study Of Prophylactic Intravenous Ondansetron On Spinal Anaesthesia Induced Hypotension Versus Placebo.

The present study is a Prospective, Randomized Double Blind study done after approval of Institutional Ethics Committee  satisfying all inclusion and exclusion criteria planned for any non-obstetric surgery under spinal anaesthesia.

Material used were Quincke type spinal needle of 25 gauge, Sterile 5 cc and 10 cc syringes. Bupivacaine 0.5% Heavy ampoule, Injection Ondansetron 8mg/4ml ampoule, Injection Atropine , Injection Mephenteramine, Emergency drugs, IV Fluids, Anaesthesia workstation, suction apparatus Laryngoscope and ET Tubes of various sizes.

After careful preoperative assessment of all patients’ standard monitors including NIBP, ECG, and pulse oximeter will be attached to the patient.

Anesthesiologist blinded to the prepared drug solution slowly administered 10 ml solution over 10 seconds. After 5 minutes, spinal anaesthesia will be performed in L3-L4 interspace with 25 G Quincke’s spinal needle using 3.0 ml of 0.5% heavy bupivacaine in sitting position. Patient will be immediately placed in supine position. SBP, DBP, MAP, HR and oxygen saturation will be recorded in individual proforma at the time of spinal anaesthesia and then at an interval of three minutes up to 15 minutes and then every 5minutes. Patients developing the primary endpoint of hypotension (systolic blood pressure 20% in baseline values) will be treated with injection mephentermine 6 mg IV, and those developing bradycardia (heart rate<50bpm) will be treated with injection atropine 0.6mg IV. Surgery will be allowed to start once sensory and motor blockade is achieved.