Laparoscopic Cholecystectomy

Nausea is a sensation of unease and discomfort in upper stomach with an involuntary urge to vomit. It may precede vomiting, but a person can have nausea without vomiting. Some common causes of nausea are motion sickness, dizziness, migraine, fainting, gastroenteritis, food poisoning, side effect of many medications or as non-specific sequel of disorders like type of surgery, raised intracranial pressure, ionizing radiation, or postoperative. Nausea and vomiting in the postoperative period occurs in 20% to 30% of patients.[1] depending on surgical and patients factors. PONV can be such an unpleasant experience that patients often rate it worse than postoperative pain.[2]10 PONV may delay a patient’s discharge from postanesthesia

The etiology of PONV is multifactorial during laparoscopic cholecystectomy, therefore, combination of different classes of anti-emetics are preferred to control PONV, [6] [7] [205,206] including anticholinergics, antihistamines, butyrophenones, benzamide, dexamethasone and 5-HT3 antagonists. Ondansetron, 5- hydroxytryptamine type 3 (5-HT3) receptor antagonist, blocks receptors in the CTZ as well as vagal nerve terminals. Dexamethasone has been used as an anti-emetic for a long time with limited adverse effect. The exact anti-emetic mechanism of dexamethasone is unknown, but it is thought to enhance the anti-emetic effect of 5-HT3 receptor antagonists [8] [208] that is central/peripheral inhibition of production of 5-HT, central inhibition of synthesis of prostaglandins, changes in permeability of the blood brain barrier to plasma proteins, or by releasing endorphins.[9]