Effect of Dexmedetomidine on Perioperative Haemodynamic Fluctuations in Untreated Stage 1 Hypertensive Patients Undergoing Laparoscopic Cholecystectomy- A Randomised Controlled Trial

Abstract

Introduction: Eighth Joint National Committee (JNC 8) has reclassified earlier prehypertension {Systolic Blood Pressure (SBP) 130-139 mm of Hg and/or Diastolic Blood Pressure (DBP) 80-89 mmHg} as stage 1 HTN. These patients may be at greater risk of perioperative haemodynamic instability, more so in case of laparoscopic surgeries and alpha-2 agonists premedication may be useful in such patients. Aim: To assess perioperative haemodynamic fluctuations in untreated stage 1 hypertension (HTN) patients and the role of Dexmedetomidine (Dexmed) in it. Materials and Methods: This prospective, randomised, double blind study was conducted at Pandit Bhagwat Dayal Sharma Postgraduate Institute of Medical Sciences, Rohtak, Haryana, India from March 2019 to September 2020. Sixty-five patients with stage 1 HTN not on any anti-hypertensive drugs undergoing laparoscopic cholecystectomy were enrolled and randomly divided into group D (dexmedetomidine) and group NS (Normal Saline). Group D received Dexmed 1 μg/kg over 10 minutes before induction, followed by continuous infusion of Dexmed at 0.2 μg/ kg/h and Group NS received similar volume of normal saline. Serial recording of pulse rate, Mean Arterial Pressure (MAP) and oxygen saturation was done. Postoperative sedation scores, extubation time and time to first rescue analgesia were also assessed. For analysis, quantitative variables were expressed as mean±SD and compared using unpaired and paired t-test. Mann-Whitney test was used for quantitative data that did not follow a normal distribution. Qualitative variables were expressed as frequencies/percentages and compared using Chi-square test. A p-value <0.05 was considered statistically significant. Results: A total of 60 patients (30 in group NS, mean age 38.40±10.32 years and 30 in group D, mean age 42.5±11.72 years) were analysed in the present study. In NS group, haemodynamic variations were seen at induction, Laryngoscopy and Intubation (L&I), creation and release of Pneumoperitoneum (PNP) and extubation but actual changes were within 10-12% of baseline value, whereas in group D, pulse rate and MAP remained stable and moderately lower than baseline throughout the perioperative period. An increase in extubation time was observed in group D (15.57±3.16 vs.9.15±1.60 min). Group D also had significantly higher sedation scores postextubation. Group NS patients demanded rescue analgesia early (18.33±7.46 min vs.43.53±8.57 min) (p=0.001). Conclusion: It was concluded that the administration of i.v. Dexmed 1 μg/kg over 10 minutes followed by infusion at 0.2 μg/Kg/h results in haemodynamic stability during surgical stress, slightly delayed but smooth extubation, delayed demand of postoperative rescue analgesia and mild sedation of short duration. Dexmed induced effects help in improving the recovery profile of the patient and keeping the patient more comfortable in the postoperative period.