Dexmedetomidine in Attenuation of Haemodynamic Response to Laryngoscopy in Controlled Hypertensive Patients

A prospective, randomized, blinded, placebo-controlled clinical trial was conducted in the Sindh Institute of Urology and Transplantation (SIUT) Department of Anesthesiology. Before their involvement in the study, all individuals provided written informed consent. In order to account for potential dropouts, 35 participants were recruited in each group (the dexmedetomidine group and the control group), for a total of 70 participants. The method of non-probability consecutive sampling was utilized to select the eligible participants until the necessary sample size was obtained. Randomization was done using computer-generated sequences, while allocation concealment was done using opaque, sealed envelopes. The sample was split into a 1:1 control group and a dexmedetomidine group at random. Dexmedetomidine: 0.5 μg/kg of dexmedetomidine was prepared in 20 mL of 0.9% saline to infuse in the dexmedetomidine group. Placebo: 20 mL of 0.9% saline was used to infuse in the control group. The study infusion was assigned and administered within ten minutes of the anesthetic induction, following baseline monitoring and intravenous cannulation. Non-invasive blood pressure, pulse oximetry, three-lead ECG, end-tidal CO₂ (EtCO₂), and capnography were all part of routine monitoring. Anesthesia was induced with lignocaine. After three minutes of mask ventilation, the experienced anesthesiologists carried out direct laryngoscopy and tracheal intubation, and the laryngoscopy time was measured. Anesthesia was supported by isoflurane in a mixture of air and oxygen, and mechanical ventilation was supported to keep EtCO₂ at 35 to 40 mmHg. Bradycardia (less than 50 beats per minute) was corrected using atropine 0.5 mg intravenously, and hypotension was corrected with ephedrine 5 mg intravenously.