Mind the Burden: Reducing anticholinergic medicines in the elderly ICU population

Introduction
The proportion of older adults (≥65 years) admitted to the ICU is increasing in the UK. This population is particularly vulnerable because of frailty, polypharmacy and increased susceptibility to medication-related adverse effects, alongside the unique challenges of critical illness and complex post-operative recovery in the ICU. Many medications used peri-operatively and in the ICU have anticholinergic properties, increasing the risk of delirium, falls, urinary retention, prolonged ICU stay, and poorer clinical outcomes. We undertook a quality improvement project to increase awareness of anticholinergic burden (ACB) and promote medication optimisation through use of the ACB score.

Methods
A retrospective review of ICU admissions over a two-week period identified patients aged ≥65 years and determined whether an ACB score had been documented. Admission ACB scores were also calculated retrospectively. A reference guide was then developed listing commonly used ICU and peri-operative medications, their ACB scores, and lower-burden alternatives. This was distributed to ICU doctors and pharmacists alongside posters and education at daily handovers. A further one-week audit assessed ACB score documentation and medication optimisation.

Results
During the initial two-week period, 45 patients were admitted to ICU, of whom 20 (44%) were aged ≥65 years. No patients had an ACB score documented, and the mean calculated ACB score was 3.3 (range 1–8). Following the intervention, 26 patients were admitted over one week, including 14 (53%) aged ≥65 years. ACB scores were documented in 5/14 patients (35%). Of these, 2/5 (40%) had their ACB reduced following medication review. The mean ACB score decreased from 3.0 to 1.8 after medication optimisation.

Conclusion
Older adults represent a substantial proportion of ICU admissions and frequently have a high anticholinergic burden. A simple educational intervention through the use of posters improved ACB score documentation and facilitated medication optimisation. Incorporating routine ACB assessment into ICU practice may help reduce anticholinergic burden and improve outcomes in this unique, vulnerable patient group.