B. Prater, D. Henderson, D. Nielsen, K. Fletcher

King's College Hospital, London, UK


At our tertiary hospital, which undertakes regular paediatric endoscopy lists, endoscopy nurses routinely test pre-operative blood glucose in all children​. Anecdotally, it was felt that 30-50% of children were hypoglycaemic (capillary blood glucose (CBG) <4 mmol/L) requiring action​ and most notable in children undergoing pre-procedure bowel preparation.

Many of the adverse effects from pre-operative fasting are under-reported and difficult to quantify. These include hypoglycaemia, metabolic acidosis, dehydration, and adverse cardiovascular effects [1]. Discomfort, hunger, thirst, and irritability – especially in toddlers and young children, can have a potentially significant influence on the peri-operative journey [2]. It is important to avoid/minimise negative experiences, particularly in children who need repeat surveillance procedures who may develop procedural-anxiety promoting non-compliance .


This audit investigated the incidence of hypoglycaemia in 20 children in the endoscopy suite, where CBG measurement is routine, and 20 children in the day surgery unit (DSU), where CBG measurement is not established practice. The sole exclusion criterion was children with known liver disease. Data included  demographics, fasting durations, use of bowel preparation, CBG measurement and treatments if CBG <4 mmol/L. Audit standards referenced the starvation instructions from the paediatric endoscopists. Current starvation guidelines for bowel preparation patients target solids starvation of at least 20.5 hours and liquids for 2.5 hours.

Data were analysed in RStudio for Mac.


40 children were recruited, 20 in endoscopy and 20 in DSU. Median age was 14 years (IQR 10-15.3), median weight was 45.4 kg (IQR 29 – 58.5) and median height was 158 cm (IQR 130.8 - 167). 24 were male and 16 were female. 33 received bowel preparation. Median starvation duration for solids was 21.7 hours (IQR 13.8 - 26). For clear fluids this was 5 hours (IQR 4 – 8). Median CBG was 4.4 mmol/L (IQR 3.7 - 4.8). 15 patients (37.5%) were hypoglycaemic with CBG <4.0 mmol/L. 2 (5%) patients had CBG < 3.0 mmol/L. All 15 hypoglycaemic patients were received treatment: 2 orally and 13 IV. 14 of the 15 hypoglycaemic patients had received bowel preparation. Of the hypoglycaemic patients, 6 were in DSU, 9 in the endoscopy suite. The attached graph shows the distribution of children by hypoglycaemia and prescription of bowel preparation.


Endoscopy requires prolonged starvation ± bowel preparation to ensure safe and complete examinations. Despite high-quality, robust starvation guidance, hypoglycaemia was common​. All hypoglycaemic episodes were outwardly asymptomatic but direct questioning for symptoms was not routinely undertaken.

Strategy for change focuses on working with paediatric endoscopy team in modifying starvation guidelines to include routine clear apple juice 2-hours pre-procedure and lollipops on admission. Once changes are agreed and implemented, we will re-audit with an aim for 0% hypoglycaemia pre-endoscopy.


1 - Fawcett, W.J. and Thomas, M. (2019) Pre-operative fasting in adults and children: clinical practice and guidelines. Anaesthesia 74: 83-8. https://doi.org/10.1111/anae.14500Pre-operative fasting in adults and children: clinical practice and guidelines https://doi.org/10.1111/anae.14500​

2 - Frykholm P, Schindler E, Sümpelmann R, Walker R, Weiss M (2018) Preoperative fasting in children: review of existing guidelines and recent developments. Br J Anaesth 120: 469-74. doi: 10.1016/j.bja.2017.11.080

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