Diagnostic value of ultrasound examination of gastric contents and volume in patients with acute coronary syndrome undergoing primary percutaneous coronary intervention: literature review and own research

Background. Preoperative gastric ultrasound allows assessing the risks of aspiration and choosing the optimal strategies of anesthetic support. The aim of the study is to establish the diagnostic value of ultrasound examination of gastric contents and volume in patients with acute coronary syndrome undergoing primary percutaneous coronary intervention, using the results of our own studies; to review the literature on preoperative fasting in adults and children. Materials and methods. The research included 12 patients with acute coronary syndrome who underwent primary percutaneous coronary intervention with anesthetic support. The time of the last meal and fluid intake was noted, and ultrasound imaging of the gastric antrum was performed. Results. Eleven patients reported the time of preoperative fasting; one patient was admitted in a medication-induced sleep after resuscitation and return of spontaneous circulation, and the information about the last solid food and fluid intake was not available. Four patients were classified as grade 0 (three cases) and grade 1 (one case) on ultrasound diagnosis, which corresponded to a minimal and ≤ 1.5 ml/kg (≤ 100 ml) gastric contents at the level of baseline gastric secretion or a minimal residual volume of clear fluid drunk and, consequently, a low risk of aspiration. One patient was classified as grade 2 with a cross-sectional area of 14 cm2, which corresponded to 142 ml of fluid for age and indicated a large gastric volume (> 1.5 ml/kg) and a high risk of aspiration. In 7 patients, a full stomach with thick liquid/solid food and high risks of regurgitation and aspiration were diagnosed; of these, 3 people had an early phase after solid food intake, and 4 individuals (including a patient with unknown nutritional status) had a late phase. The ultrasound results were consistent with and complemented the information regarding food and fluid intake. Conclusions. The study demonstrated the diagnostic value of gastric ultrasound as a non-invasive method for assessing the contents, volume and phase of emptying in patients with acute coronary syndrome undergoing primary percutaneous coronary intervention.