Effect of preoperative oral paracetamol on gastric volume and pH
Research type
Research Study
Full title
A Randomised Controlled Trial Examining the Effect of Preoperative Oral Paracetamol on Gastric Residual Volume and pH in children, in the context of a 1 hour clear fluid fast
IRAS ID
266252
Contact name
Emily Saffer
Contact email
Sponsor organisation
King's College Hospital NHS Foundation Trust
Clinicaltrials.gov Identifier
Duration of Study in the UK
0 years, 8 months, 1 days
Research summary
Patients fast before anaesthesia to reduce the risk that residual gastric contents (GRC) could be regurgitated and aspirated into the lungs once anaesthetised. Lower acidity (pH > 1.8) is known to be protective in event of aspiration in animal studies, even at higher volumes of GRC.
Recent European and UK guidelines have reduced the length of the recommended clear fluid fast to 1 hour for children, as there is no significant difference in GRC, pH or volume in children fasted for 1 hour compared to 2 hours.
Some anaesthetists administer oral paracetamol syrup to children pre-operatively as an alternative to intravenous administration of paracetamol during their surgery. The oral route has been suggested to be pleasant for children, cheaper, more convenient, and reduce the risk of drug errors associated with the IV preparation. However it is not classified as a clear fluid.
A 2018 study demonstrated that giving paracetamol orally up to 8 minutes before induction of anaesthesia was not associated with an increase in the volume of stomach contents, and that the pH of stomach contents was higher than without paracetamol, suggesting that this approach might not present any increased aspiration risk. This was in the context of a mean fluid fast of 5 hours.This study seeks to administer a set volume (3ml/kg) of water orally 1 hour before anaesthesia, and to compare Gastric Residual Volume (GRV) in groups of children with and without oral paracetamol syrup given at the same time.
Once anaesthesia has been induced, a thin soft tube will be passed from the into the stomach to remove any GRC. The study outcomes will be the GRV, and the pH. We will include children aged from 44 weeks corrected gestational age maximum weight of 25kg having elective surgery at King’s college hospital and the Royal London Hospitals.
REC name
South West - Cornwall & Plymouth Research Ethics Committee
REC reference
20/SW/0014
Date of REC Opinion
20 Apr 2020
REC opinion
Further Information Favourable Opinion