EFFECT OF DEXMEDETOMIDINE INFUSION ON PERIOPERATIVE HAEMODYNAMIC STABILITY IN PATIENTS UNDERGOING LAPAROSCOPIC CHOLECYSTECTOMY: A PLACEBO CONTROLLED, RANDOMISED BLINDED STUDY

In the current era, laparoscopic cholecystectomy is considered the gold standard of treatment for cholelithiasis due to the benefits of better postoperative pain profiles, lesser surgical wound complications and reduced hospital stay.[1]  Anaesthetic manoeuvres like direct laryngoscopy, tracheal intubation and extubation cause sympathetic stimulation. Moreover, the creation of pneumoperitoneum leads to an increase in plasma norepinephrine, epinephrine levels and plasma renin activity[2].These changes lead to an increase in heart rate, blood pressure, systemic and pulmonary vascular resistance and reduced cardiac output[2]. The reverse Trendelenburg position required for the surgical procedure also leads to reduction in venous return thereby causing a further reduction in cardiac output[3].The haemodynamic changes predispose the myocardium to ischaemia which may be life threatening in vulnerable patients[2]. In the past, various drugs like opioid analgesics, benzodiazepines, beta blockers, calcium channel blockers have been used to attenuate this stress response. α2  adrenergic agonists are increasingly being used to reduce stress response  to anaesthesia and surgery for their analgesic, anxiolytic, sedative and sympatholytic properties[4,5]. Dexmedetomidine (an α2 agonist) is a commonly used drug which decreases sympathetic tone, arterial pressure and heart rate in a dose dependent manner and produces sedation without causing respiratory depression[3,4].

In this study, we intend to give intravenous infusion of Dexmedetomidine hydrochloride at the rate of 0.4 microgram per kilogram of body weight per hour in Sodium Chloride 0.9% starting from 10 minutes prior to induction of anaesthesia till the end of operation and compare it with intravenous infusion of Sodium Chloride 0.9% as placebo and observe the effects on haemodynamic stability following laryngoscopy and intubation, pneumoperitoneum and extubation. In this randomised controlled study, the null hypothesis that dexmedetomidine does not reduce heart rate and blood pressure in patients undergoing laparoscopic cholecystectomy would be investigated.

 REFERENCES:

1) 1)   Samel SA, Patil BM, Nigalye N. Effect of Low Dose Dexmedetomidine Infusion on Hemodynamics in Patients Undergoing Laparoscopic Cholecystectomy: A Prospective Observational Study. Journal of Contemporary Medical Research. 2017;4(10):2069-74.

2)  2)  Manne GR, Upadhyay MR, Swadia VN. Effects of low dose dexmedetomidine infusion on haemodynamic stress response, sedation and post-operative analgesia requirement in patients undergoing laparoscopic cholecystectomy. Indian journal of anaesthesia. 2014 Nov;58(6):726.

 3)  3)  Bhattacharjee DP, Nayek SK, Dawn S, Bandopadhyay G, Gupta K. Effects of dexmedetomidine on haemodynamics in patients undergoing laparoscopic cholecystectomy-A comparative study. Journal of Anaesthesiology Clinical Pharmacology. 2010 Jan 1;26(1):45.

 4)  4)  Rachit B, Nanda HS, Mahesh K. Evaluation of Dexmedetomidine-0.5 mu g/kg and 1 mu g/kg in Blunting the Responses to Laryngoscopy and Intubation. INTERNATIONAL JOURNAL OF SCIENTIFIC STUDY. 2016 Feb 1;3(11):147-53.

5)   5)Ghodki PS, Thombre SK, Sardesai SP, Harnagle KD. Dexmedetomidine as an anesthetic adjuvant in laparoscopic surgery: An observational study using entropy monitoring. Journal of anaesthesiology, clinical pharmacology. 2012 Jul;28(3):334.