Highlights
- •PoCUS is point-of-care ultrasound.
- •Evidence-based suggestions for using gastric PoCUS in obstetrics.
- •Antral cross-sectional area a valid surrogate for gastric fluid volume estimation.
- •Gastric emptying of fluid, not food, appears unaffected by term pregnancy or labour.
- •Gastric PoCUS adds information facilitating individual aspiration risk assessment.
Abstract
Personalised risk assessment of the likelihood of pulmonary aspiration is recommended
for pregnant women undergoing general anaesthesia and gastric point-of-care ultrasound
(PoCUS) may help to achieve this. Traditionally, risk assessment is based upon adherence
to fasting times, but gastric emptying may vary during pregnancy and surgery often
needs to be expedited. We systematically reviewed the evidence for gastric PoCUS up
to August 2018 in pregnant and postpartum women to determine whether it can identify
and quantify stomach contents, provide aspiration risk assessment via qualitative
or quantitative means, and determine how gastric emptying is affected by pregnancy.
Twenty-two articles comprising 1050 participants were included and studies were classified
by qualitative or quantitative findings. The evidence suggests that gastric PoCUS
is a reliable and feasible method of imaging the stomach in pregnancy in clinical
practice. Qualitative assessment via the Perlas grading system can provide rapid assessment
of gastric volume states. If fluid is visible, identification of patients at high
risk of pulmonary aspiration requires measurement of antral cross-sectional area.
Cut-off values of 608 mm2 and 960 mm2 are recommended in the semi-recumbent and right lateral semi-recumbent positions,
respectively. Validated methods to quantify stomach volumes are available, however
their usefulness is currently restricted to research. Gastric PoCUS also provides
evidence that gastric emptying of ingested food is delayed by term pregnancy, labour
and during the early postpartum period. However, the passage of fluids through the
stomach appears unaffected throughout the peripartum period.
Keywords
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Article info
Publication history
Published online: May 28, 2020
Accepted:
May 19,
2020
Identification
Copyright
© 2020 Elsevier Ltd. All rights reserved.
