Ultrasound assessment of gastric contents in children undergoing elective ear, nose and throat surgery: a prospective cohort study

Abstract

Ultrasound examination of the gastric antrum allows reliable assessment of gastric contents and volume. Postoperative assessment of gastric contents before recovery from anaesthesia could help the physician to choose the most appropriate extubation technique after surgery in children. In this prospective observational study, we assessed whether significant changes occurred in gastric contents during the intra-operative period in children undergoing elective ear, nose and throat (ENT) surgery. Children aged between six months and 16 years were recruited consecutively. Ultrasound examination of the antrum was performed before induction of anaesthesia and at the end of surgery before tracheal extubation, and included quantitative and qualitative assessment of gastric contents. The mean (SD) gastric volume was 0.28 (0.30) ml.kg before surgery and 0.27 (0.30) ml.kg after surgery, p = 0.82. No solid contents were identified in the antrum, and the gastric volume was < 1.5 ml.kg in all patients during both ultrasound examinations. Our results suggest that, after elective ENT surgery, children are not at risk of a full stomach before tracheal extubation, and that pulmonary aspiration of blood that may occur after elective ENT surgery is probably not related to regurgitation of ingested blood from the stomach.

Gastric Ultrasound for the Regional Anesthesiologist and Pain Specialist

“…These values are remarkably similar in obstetric and nonobstetric adult patients, as well as in pediatric and obese populations. [11][12][13][20][21][22][23][24] It seems reasonable therefore to use a threshold of 1.5 mL/kg to discriminate between fasting and greater than fasting gastric volumes. [15][16][17]23 Several authors have studied the mathematical correlation between the gastric antral cross-sectional area (CSA) and the total gastric fluid volume, 13,18,23,[25][26][27][28][29][30][31][32][33][34] with the majority reporting a linear correlation.…”

“…24,48,49 For optimal imaging of children less than 40 kg, a linear high-frequency transducer is recommended (Fig. 10), whereas a low-frequency large curvilinear transducer is typically required for children weighing more than 40 kg.…”

“…48 The distribution of antral grades and gastric volume per unit of body weight are surprisingly similar in fasting children and adults. 13,24,48 As in adults, a linear correlation has been described between antral CSA and gastric volume, and it is the basis of a mathematical model of gastric volume in children: volume = −7.8 + (3.5 Â RLD CSA) + (0.127) Â age (months). 13 Of note, this model was developed based on a cohort of 100 fasted children between the ages of 11 and 216 months and has not yet been validated in children with gastric volumes larger than 1.5 mL/kg.…”

“…In a follow-up study, preoperative US assessment of gastric contents in a cohort of nonelective pediatric surgical patients resulted in changes in management in approximately 50% of cases. 50 Gastric US has been used to assess for the intraoperative accumulation of gastric content (ie, ingested blood) during elective ear, nose, and throat surgery in children 24 and to identify and monitor ingested foreign bodies in children presenting to the emergency department. 51-54…”

Leading papers in pediatric anesthesia from the last year

“…Desgranges et al 27 , em um estudo observacional e prospectivo, avaliou o conteúdo gástrico de crianças que eram submetidas à cirurgias otorrinolaringológicas. Os autores mostraram que não havia aumento do conteúdo gástrico durante a cirurgia, o que não aumentaria o risco de aspiração de sangue vindo do estômago após a extubação.…”