• endocrinology
• therapeutics

Two key drivers underpinned the most controversial changes to the guideline—revised recommendations regarding fluids and an increased emphasis on treating shock. The first was the PECARN FLUID study (Pediatric Emergency Care Applied Research Network), a randomised controlled trial comparing a rapid with a slower rehydration fluid regimen.1 The second was concern, triggered by three deaths (unpublished audit data), that the fluid regime introduced in 2015 may be overly restrictive, increasing morbidity, and that anxiety about fluids may be inhibiting adequate resuscitation.

Cerebral oedema affects 1% of admissions with diabetic ketoacidosis (DKA). The traditional view that cerebral oedema is mediated by osmotic changes and may be precipitated or exacerbated by fluid administration has resulted in more restrictive fluid regimes.2 However, there is little evidence that such regimes have reduced the incidence of cerebral oedema.3–5 Evidence now suggests cerebral oedema results from initial cerebral hypoperfusion followed by a vasogenic or reperfusion injury.2 Cerebral oedema occurs at presentation, prior to any fluid administration, in up to 19% of cases.6 Asymptomatic subclinical cerebral oedema is evident in 50% of cases on MRI.7 Why some patients develop overt cerebral oedema remains unclear, and the role of fluids is contentious.

Of the six predominantly small case-control studies cited in the National Institute for Clinical Excellence (NICE) Guidance NG18 from which the previous 2015 British Society for Paediatric Endocrinology and Diabetes (BSPED) guideline evolved, four studies suggested that fluids were not a causal factor for cerebral oedema.5 6 8 9 The prospective UK case–control study, given the highest evidence rating, suggested higher fluid volumes may be a factor.10 However, the mean pH …