Effect of throat pack on gastric volume measured using ultrasound in patients undergoing elective ENT procedures under controlled hypotensive anaesthesia with endotracheal intubation - A prospective randomized, double-blinded study.

1.     Surgeries of the nasal cavity are among the commonly performed otorhinolaryngology procedures across the world.Insertion of a throat pack to minimise trickling down of the blood into the trachea and esophagus is a commonly practiced technique worldwide, despite emergence of literature evidence against its use. [1] The common belief is that in the absence of insertion of a pharyngeal pack, blood enters into the stomach and is a potent emetic resulting in increased incidence of postoperative nausea and vomiting (PONV). [2]Hence, surgeons often request for the insertion of a throat pack while performing procedures like septoplasty and Functional Endoscopic Sinus Surgery (FESS) so as to reduce gastric distension and thereby the incidence and severity of PONV. It may also help the surgeons by providing a relatively dry field to operate by absorbing blood and irrigation fluids used during the surgery.

However, recently published recommendations are against the routine practice of placing throat packs. [1]Insertion of pharyngeal packs increases the incidence and severity of sore throat. [3, 4] Also, there is published literature comparing the incidence of PONV with and without the insertion of throat pack and found no difference in the incidence of PONV. [3] Moreover, the leftover throat pack by mistake is a “never event’ (retained foreign body) and may result in serios consequences including airway obstruction and hence, their routine insertion is now being questioned. [1].

The major cause of bleeding in the intraoperative period during FESS surgery under general anaesthesia (GA) is attributed to peripheral vasodilatation and to surgical stimulus causing increases in blood pressure and thereby bleeding. Better vascularity of the nasal cavity also plays a minor role. To reduce intraoperative blood loss, many strategies are used including the use of controlled hypotensive anaesthesia, infiltration of nasal cavity with local anaesthetic and adrenaline, and slight head end elevation by 10 to 15Ëš.  Controlled hypotensive anaesthesia by using pharmacological agents is a commonly practiced and useful technique. Intravenous administration of Dexmedetomidine to provide hypotensive anaesthesia is found to be effective in reducing intraoperative bleeding. It also attenuates the response to surgical incision by providing analgesia. All this may help in providing a relatively avascular field for the surgeons to operate, thereby reducing the amount of irrigation fluid required in the intraoperative period, resulting in lesser gastric distension.

Hence, we would like to assess the gastric volume of the patients undergoing elective FESSunder controlled hypotensive anaesthesia with endotracheal intubation with and without the insertion of throat pack.