. Impact of Modified Anesthesia Management for Pediatric Patients With Williams Syndrome.


This retrospective observational cohort study at a single quaternary paediatric surgical centre aimed to assess the impact of a risk-based care protocol for children with Williams Syndrome (WS) undergoing general anaesthesia. Williams syndrome is a congenital multisystem disorder involving connective tissue, cardiovascular and the central nervous system. It effects approximately 1 in 10,000 live births and is associated with a 10.4% risk of adverse cardiovascular events under anaesthesia. Recent work by Bird et al (2015) and Collins et al (2018) have developed a risk stratification for children with WS, dividing into low, moderate and high risk, based primarily on history, ECG and echocardiogram. The authors developed a care protocol based on this risk stratification with four primary care objectives: risk stratification, IV hydration, IV induction, and early use of continuous vasoactive substances.


From 2017, a new care protocol was introduced for children with WS undergoing general anaesthesia. They were pre-assessed and divided into low, moderate and high risk. Essentially low risk WS followed the hospital standard anaesthetic pathway, moderate risk children received 2 hours of hyper-hydration pre-operatively, and high risk children were admitted overnight prior to surgery for IV hydration. All children received IV induction and early continuous vasoactive drugs were recommended for blood pressure control. Data was then collected (2017-2019) looking for adverse cardiovascular events and greatest alteration to pre-op BP over the first hour. This was compared to the “historic group” of WS undergoing anaesthesia from 2008-2017.


The primary positive finding was a reduction in mean reduction in systolic blood pressure from 17.5% in the historic group to 9% in the intervention arm. There was a signal to benefit of reduction in adverse cardiovascular events in the intervention group though this was not statistically significant.


The study addresses a relatively uncommon but important patient group with a high risk of adverse outcomes. With recent publications on risk stratification, it is certainly relevant and interesting to read how a major quaternary hospital is approaching care of this group. The paper presented describes clearly the care model that aims to mitigate risk through a logical approach to avoiding dehydration and maintaining systemic vascular resistance at the point of induction and as such will be a useful reference point for other centres looking to develop protocolised care for WS.

The paper is necessarily limited by the low total patient numbers and I think caution is required in inferring too much from the evidence presented. The paper compared two heterogenous datasets with differing patient demographics and surgeries. It is likely many aspects of care have changed in the time periods compared, such as the increasing role of interventional cardiology (for example 36% vs 24% cardiothoracic surgery in the historic vs intervention groups). It is difficult to attribute all the demonstrated benefit to the anaesthetic technique alone.

Reviewed by Dr Phil Dart