The impact of different liaison psychiatry models on the emergency department: A systematic review of the international evidence

Objective This review aimed to evaluate the current evidence for what impact different Liaison Psychiatry (LP) services are having on Emergency Departments (ED). Mental Health (MH) problems contribute to 12 million annual US ED attendances and 5% in the UK. Methods Databases were searched for articles describing LP services for adult MH patients attending EDs which reported ED care-related outcomes, published since 2000. Articles were screened and relevant articles quality assessed and narratively synthesized. Results 3653 articles were identified and 17 included in the review. Study designs were overall of poor-moderate quality, using retrospective before-and-after study designs. LP services were categorized into four models. Models with MH personnel integrated into the ED team or triage reduced patient waiting time to be seen, may reduce patients leaving without being seen and have high staff satisfaction. Co-located MH space or personnel reduced patient waiting times. Care agreements with existing psychiatry teams don't affect waiting times or ED length of stay. Transferring patients to external services reduces patients' time in the ED. There is insufficient evidence about patient satisfaction, costs, and onward care. Conclusions Waiting times are shortened by MH personnel integrated into the ED and are more satisfactory to staff than other LP models. The involvement of a psychiatrist in the LP team improves the care quality. All models may improve safety for patients but most evaluations are of poor quality and therefore there is still insufficient evidence to recommend one service model over another and further robust research is required