Ultrasound-guided gastric antral cross-sectional area assessment for anaesthetic management in emergency laparoscopic appendectomy: a retrospective cohort study

To evaluate whether preoperative gastric ultrasound assessment of the gastric antrum, integrated with a predefined aspiration-risk management protocol, was associated with differences in anaesthetic management and perioperative outcomes in adults undergoing emergency laparoscopic appendectomy. We retrospectively analysed 158 adults who underwent emergency laparoscopic appendectomy, including 80 patients managed with preoperative gastric antral ultrasound and 78 patients assessed using conventional fasting-history and clinical criteria. In the ultrasound group, gastric content was graded using the Perlas system and antral cross-sectional area (CSA) was calculated from anteroposterior and craniocaudal diameters. A CSA threshold of 340 mm² was incorporated into a predefined risk-stratification algorithm that determined the induction strategy. Perioperative reflux/aspiration events, haemodynamic variables, workflow indicators, recovery outcomes, anaesthesia-related adverse events, and pulmonary complications were compared between groups. The ultrasound group had lower documented rates of perioperative nausea/vomiting (1/80 [1.25%] vs. 9/78 [11.54%]) and reflux/aspiration events (1/80 [1.25%] vs. 8/78 [10.26%]). Haemodynamic fluctuations were smaller, and preoperative assessment, surgical waiting, anaesthetic induction, PACU stay, time to first oral intake, and hospital stay were shorter in the ultrasound group. Anaesthetic induction-related adverse events were also less frequent. Pulmonary complications within 72 h did not differ significantly between groups. In this single-centre retrospective cohort, implementation of gastric ultrasound-guided aspiration-risk stratification was associated with more individualised anaesthetic planning and favourable perioperative process and safety outcomes. Prospective multicentre studies with standardised operator training, formal measurement-reliability assessment, and adjustment for temporal and clinical confounders are required before causal conclusions can be drawn.