Incidence of Stomach Fullness and Associated Factors in Elective Surgical Patients

Summary

The aim of this prospective, observational study is to evaluate the incidence of residual gastric content in elective surgical patients who adhered to preoperative fasting guidelines and to investigate associated patient-related factors. Ultrasound (USG) has been identified as a valuable tool for assessing residual gastric content, and this study compares its efficacy against traditional questionnaire-based predictions. The study also examines the practicality and accuracy of different gastric volume estimation formulas and evaluates their correlation with aspiration risk.

A total of 475 patients were enrolled in the study, of whom 404 completed both the questionnaire and USG examination. All participants were adult patients scheduled for elective surgery, following standard fasting protocols. The ultrasound examination assessed the presence of solid or fluid content in the stomach, and patients were classified according to qualitative Perlas risk scores (Grade 0: Low, Grade 1: Moderate, Grade 2: High risk of aspiration). The questionnaire collected patient-reported factors, such as symptoms of early satiety, history of cholelithiasis, and comorbidities like diabetes or chronic obstructive pulmonary disease (COPD).

The primary objective of this study was to evaluate the efficacy of USG in detecting residual gastric content and compare it with questionnaire-based risk predictions. Logistic regression analysis identified early satiety and cholelithiasis as significant predictors of a full stomach and higher aspiration risk. Fasting duration was found to have a protective effect, reducing the likelihood of a full stomach. While many patient characteristics traditionally associated with delayed gastric emptying, such as age and diabetes, did not significantly correlate with the outcomes, early satiety and cholelithiasis proved to be key factors influencing gastric content.

In addition, this study explored the performance of several gastric volume estimation formulas, including the Michiko, Bouvet, and Perlas 2019/2020 formulas. The findings indicated significant limitations in these formulas, with many patients being estimated to have negative gastric volumes, particularly by the Michiko and two of Perlas\' formulas. This highlights the inadequacies of current formulas in accurately predicting gastric volume, necessitating further refinement and development of new models that better account for physiological variability.

Furthermore, the agreement between questionnaire-based predictions and USG findings was assessed using Cohen's Kappa, which indicated fair agreement (Kappa value = 0.282). This suggests that while the questionnaire can serve as a screening tool to identify patients at risk of aspiration, it cannot replace the accuracy and reliability of USG in clinical practice.

Secondary objectives of the study included comparing the time-efficiency and ease of implementation between USG and the questionnaire-based assessments. USG proved to be more time-efficient, taking an average of 2.5 minutes per examination, compared to 3-5 minutes for completing the questionnaire. This speed, combined with its objective nature, underscores USG's value as a practical tool in the preoperative setting.

In conclusion, USG was found to be an effective and efficient tool for assessing residual gastric content and predicting aspiration risk, outperforming traditional questionnaire-based assessments. The inadequacy of current gastric volume estimation formulas points to the need for further research to develop more accurate and context-specific assessment tools. Comprehensive preoperative evaluation incorporating USG and patient-reported symptoms may improve patient safety by reducing the risk of aspiration during elective surgery.

Conditions

• Gastric Emptying
• Preoperative Care
• Preoperative Fasting
• Elective Surgical Procedures
• Ultrasonography

Sponsors & Collaborators

• Recep Tayyip Erdogan University

  lead OTHER

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2020-10-05

Primary Completion

2022-09-29

Completion

2022-10-10

Countries

• Turkey (Türkiye)

Study Locations