Comparative evaluation of paracetamol and dexmedetomidine on peri-operative haemodynamics and post-operative analgesia in patients undergoing laparoscopic cholecystectomy under general anaesthesia

Laparoscopic cholecystectomy is gold standard surgical treatment for cholelithiasis

and cholecystitis. It is a minimally invasive procedure in which inert gas is insufflated into

the abdomen, creating pneumoperitoneum. Due to the combined effect of anaesthetic agents,

positioning of patient, absorption of gas and pneumoperitoneum, there is occurrence of

marked hemodynamic changes. Peri-operative hemodynamics monitoring plays a critical

role for improving post-operative outcomes. In an anaesthetized patient, it provides crucial

information regarding cardiac output, volume status, tissue perfusion, and depth of anaesthesia

and adequate pain control. After CO2 insufflation, if the intraabdominal pressure is more than 10

mmHg, then there is significant alteration of haemodynamics due to vena cava compression

and pooling of blood in lower extremities, causing decrease in venous return and cardiac

output. The increase in peripheral vascular resistance is contributed by increase in intra

thoracic pressure due to increased intra-abdominal pressure and also by the release of

catecholamines and vasopressin due to mechanical stimulation of peritoneal receptors.

Sudden stretching of peritoneum during laparoscopy may lead to arrhythmias (bradycardia).

and asystole).

Post-operative pain management and monitoring of pain relief have become important

post-operative quality measure. The desired goal is to alleviate or eliminate pain and its

discomfort in patients with the fewest side effects.3 Adequate pain relief is crucial to treating

patients undergoing surgery. There have been studies suggesting that, out of the total number of

patients undergoing surgery, more than 80% experience acute post operative pain and out of

these, approximately 75%, report severity of post operative pain as moderate , severe or

extreme. There are also evidences to suggest that less than 50% of patients reports adequate

pain relief after surgery.4 For the management of post operative pain, various

pharmacological agents have been tried (opioid vs non-opioid) via different routes ( oral,

intravenous, neuraxial, and regional).

Dexmedetomidine is a highly selective alpha-2 receptor agonist. It is having

sympatholytic, sedative, analgesic, and opioid-sparing properties and does not cause respiratory

depression. It also decreases the incidence of postoperative nausea and vomiting. Intravenous

dexmedetomidine also has efficacy in improving perioperative hemodynamic stability and

post-operative analgesia. In addition, it also decreases the intraoperative consumption of

anaesthetics and opioids, It also has direct antiemetic effect by activating alpha-2

receptors. Minor side effects like hypotension and bradycardia can occur with

dexmedetomidine .

Paracetamol is widely used as an antipyretic and analgesic and its presumed mechanism  of

action being inhibition of central cycloxygenase (COX 3), which causes decreased production

of prostaglandins in the CNS. It might also act through opioidergic system and NMDA receptors

and by regulation of inhibitory serotonergic pathways.

Since perioperative hemodynamics and post operative pain are the major

concerns in patients undergoing laparoscopic cholecystectomy under general anaesthesia, we

decided  to perform a study to compare the effect of Paracetamol and

dexmedetomidine on perioperative hemodynamics and postoperative analgesia.