Safety and Efficacy of KetamineDexmedetomidine versus Ketamine-Propofol Combination for Short-term Sedation in Postoperative Obstetric Patients on Mechanical Ventilation: A Randomised Clinical Trial

Introduction: Prolonged mechanical ventilation in postoperative obstetric patients is an important cause of morbidity and mortality. Choosing intravenous sedation for these patients is challenging, as many of these drugs have unique benefits and adverse effects.There are several options are available like benzodiazepines, propofol, alfa-2 agonist, opioids and ketamine. Usually, a combination of sedatives are used to avoid dose dependent adverse effects. Aim: To evaluate the combination of Ketamine-Dexmedetomidine (KD) and ketamine-propofol for sedation in mechanically ventilated obstetric patients to compare haemodynamic changes. Secondary objectives to assess adverse effects if any, additional opioid (fentanyl) requirement and total length of intensive care unit stay. Materials and Methods: This randomised clinical study was conducted at King George’s Medical University, Lucknow, Uttar Pradesh, India, from May 2018 to August 2019. Total 67 obstetric patients, between 18-45 years of age, requiring postoperative ventilatory support, were included in the study. For sedation, 33 patient received ketamine-dexmedetomidine (group I) combination and 34 patients received ketamine-propofol (group II) combination upto 12 hours of ventilatory support. Target of sedation was to obtain Ramsay sedation scoring between 3-4. Mean Arterial Pressure (MAP) was measured at 0.5 hour, 1 hour, 2 hours, 4 hours, and at every 2 hourly till 12 hours. Pain was assessed using adult non verbal pain score. Adverse effects (tachyarrhythmia, agitation and hypersalivation) were noted. Total length of Intensive Care Unit (ICU) stay was also recorded. Results: Age of patients enrolled in the study ranged from 20 to 37 years, the mean age being 27.09±4.61 years. At baseline mean arterial pressure of patients of group I (103.82±19.26 mmHg) was higher than that of group II (96.74±13.49 mmHg) (p-value=0.085). For the rest of the periods of observation, from 0.5 hour to 14 hour,the MAP of group I remained higher as compared to group II. On intragroup comparison, group II had more fluctuation in MAP than group I. Additional requirement of fentanyl was significantly high in Group II, as compared to group I (32.4% vs. 12.1%). Mean duration of ICU stay was higher in group II, as compared to group I (30.44±7.26 hours vs 22.91±4.03 hours). Conclusion: Ketamine-dexmedetomidine is a better combination for sedation in postoperated obstetric patients on mechanical ventilation than ketamine-propofol as it provides stable haemodynamics, significantly lesser opioid requirement andtotal length of ICU stay.