Ultrasound evaluation of gastric residual volume in fasting end-stage renal failure patients

Pulmonaryaspiration of gastric contents is a serious perioperative complication. TheFourth National Audit Project by the Royal College of Anaesthetists hasreported pulmonary aspiration as the cause of more than 50% of airway-relateddeaths in anaesthesia. The resulting respiratory compromise isthought to be related to both volume and nature of the aspirate. The most commonly used measure to prevent aspiration is fasting beforeanaesthesia, and anaesthesia societies have developed guidelines forpreoperative fasting. However, these guidelines apply to healthypatients undergoing elective surgery and not reliable in patients withco-morbidities that affect gastric emptying. Gastricemptying is known to be delayed in patients with end-stage renal failure.Though certain biochemical markers have been shown to be associated with delayedgastric emptying in patients with chronic renal failure, there is no acceptablemethod of identifying such patients before anaesthesia. Gastricultrasound has recently evolved into a simple, point-of-care tool forevaluating gastric content and volume. The gastric antrum can be easilyidentified using a low frequency curvilinear probe. By visualising the antrum,not only the contents of the stomach can be determined, but also quantificationis possible by application of suitable validated methods. There ispaucity of literature with respect to the use of gastric ultrasound todetermine residual volume in patients with end-stage renal failure. Hence, thepresent study is designed to evaluate the gastric contents and volume inpatients with end-stage renal failure by gastric ultrasound.