FACTORS ASSOCIATED WITH EXIT BLOCK, AND IMPACT ON THE EMERGENCY DEPARTMENT
Authors: Mason S , Knowles E , Smith C 
Published: November 2015

Objectives & Background

Exit block occurs when “patients in the ED requiring inpatient care are unable to gain access to appropriate hospital beds within a reasonable time frame”. In the UK, exit block has been defined as occurring when a patient spends “4 hours or more in the ED from arrival to admission, transfer or discharge”. A number of factors contributing to an ED becoming blocked have been identified and include the lack of availability of a hospital bed for admitted patients, long waiting times for diagnostics/test results in the ED, and difficulties in discharging patients to their usual residence or an alternative destination. We explored whether there are characteristics of NHS acute trusts and Type 1 EDs which are associated with exit block.

Table 1

Trusts with lower compliance of four hour target (ie those at risk of exit block)

JuneOctoberDecemberCompliance with four hour target (%)80.3–98.574.9–98.162.0–97.4Less likely to have Foundation Trust status✓✓✓More likely to be located in an urban settingX✓XMore likely to contain multiple EDs within the Trust✓✓✓More likely to have a catchment population greater than 400,000✓✓✓More likely to record higher than average time spent in the ED for admitted patients✓✓✓More likely to record higher than average time spent in the ED for discharged patients✓✓XMore likely to record higher than average ‘left without being seen’✓✓✓More likely to record a higher than average ED re-attendance✓✓XMore likely to record a higher than average bed occupancy for general and acute beds✓✓✓More likely to admit 30% (or more) of the patients seen in the ED✓✓✓

Methods

Routinely available A&E SitRep data was analysed to identify the likelihood of exit block within Type 1 EDs across NHS acute trusts in England. We extracted the data containing the % of attendances admitted, transferred or discharged within 4 hours of ED arrival, and used this as a proxy for exit block. We calculated the average of this variable during a four week period for three individual months in 2014 (June, October and December).

In each month analysed, 10% (n=14) of all NHS acute trusts with a Type 1 ED were selected against common characteristics of trusts identified as having higher levels of exit block compared to those with lower levels. We identified seven NHS Trusts with lower compliance on the 4 hour target, and seven NHS Trusts reporting higher compliance levels (Table 1).

Results

Table 1 presents the results of the factors identified that appear to have an association with exit block.

Conclusion

We were limited in exploring variables where data was routinely available. However, some patterns appeared to emerge from the data and require further exploration. NHS Trusts at risk of exit block were more likely to be large trusts, located in larger catchment areas, have higher admission rates and inpatient bed occupancy and higher levels of patients leaving the ED without being seen and reattending. Some of the factors identified may well be symptomatic of exit block rather than causal, whilst other factors may be acting as proxies for differences in casemix, social deprivation or ability to access alternative urgent care services.