Preoperative Ultrasound Evaluation of Fasting Residual Gastric Volume in Patients With Previous Sleeve Gastrectomy : Comparative Study With Patients Without History of Bariatric Surgeries

No doubt, that perioperative aspiration of gastric content during anesthesia process is every anesthesiologist's nightmare, which can lead to serious morbidities and mortalities with a rate of 5% to 9 % in anesthesia airway management accidents.

Risk of aspiration usually present during induction of anesthesia due to passive regurgitation during endotracheal intubation while it may occur during recovery from anesthesia in patients with active vomiting.

It is known that the volume of residual gastric content is one of the most important factors that can lead to significant increase in the risk of perioperative pulmonary aspiration, acknowledging this fact, lead the American society of Anesthesiology (ASA) to recommend for eight hours fasting for solids (fats and/or meats), six hours for non-human milk and light meals, and two hours for clear fluids, to reduce residual gastric volume and subsequently the risk of perioperative aspiration.

There are many different ways to asses gastric content for example nasogastric tube aspiration of gastric content which is an invasive technique. Other ways include imaging tools like abdominal CT scan which is not easily done and will have extra cost on the patient . In addition, wireless motility capsules and gastric emptying scintigraphy can be used but all of them are not suitable for routine assessment.

On the other hand Point-of-Care (POC) ultrasound usage in anesthesia management has provided a wide range of rapid, bed side and non-invasive, easy and fast techniques that help to reduce the risk of morbidity and mortality. It also, helped to provide a technique for qualitative and quantitative assessments of residual gastric contents preoperatively through gastric antrum US assessment using measurement of the antral cross-sectional area.