Background Exit block (or access block) occurs when ‘patients in the ED requiring inpatient care are unable to gain access to appropriate hospital beds within a reasonable time frame’. Exit block is an increasing challenge for Emergency Departments (EDs) worldwide and has been recognised as a major factor in leading to departmental crowding. This paper aims to identify empirical evidence, highlighting causes, effects and strategies to limit exit block.

Methods A computerised literature search was conducted of English language empirical evidence published between 2008 and 2014 using a combination of terms relating to exit block in ED.

Results 233 references were identified following the computerised search. Of these, 32 empirical articles of varying scientific quality were identified as relevant and results were presented under a number of headings. The majority of studies presented data relating to the impact of exit block on departments, patients and staff. A smaller number of articles evaluated interventions designed to reduce exit block. Evidence suggests that exit block is more likely to occur in more densely populated areas and less likely to occur in paediatric settings. Bed occupancy appears to be associated with exit block. Evidence supporting the impact of initiatives pointed towards increasing workforce and inpatient bed resources within the hospital setting to reduce block.

Conclusions Further evidence is needed, especially within the NHS setting to increase the understanding around factors that cause exit block, and interventions that are shown to relieve it without compromising patient outcomes.