A graphical assessment of emergency surgical list efficiency to determine operating theatre capacity needs

Unlike elective lists, full utilisation of an emergency list is undesirable, as it could prevent patient access. Conversely, a perpetually empty emergency theatre is resource wasteful. Separately, measuring delayed access to emergency surgery from time of booking the urgent case is relevant, and could reflect either deficiencies in patient preparation or be because of an occupied (over-utilised) emergency theatre.

We developed a graphical method recognising these two separate but linked elements of performance: (i) delayed access to surgery and (ii) operating theatre utilisation. In a plot of one against the other, data fell into one of four quadrants, with delays associated with high utilisation signifying the need for more emergency capacity. However, delays associated with low utilisation reflect process deficiencies in the emergency patient pathway. We applied this analysis to 73 consecutive lists (>300 cases) from two UK hospitals.

Although both hospitals experienced similar rates of delayed surgery (21.8% vs 21.0%; P=0.872), in one hospital 83% of these were associated with low emergency theatre utilisation (suggesting predominant process deficiencies), whereas in the other 73% were associated with high utilisation (suggesting capacity deficiency; P<0.0001). Increasing emergency capacity in the latter resulted in shorter delays (just 6.7% cases excessively delayed; P<0.0001 for effect of intervention).

This simple graphical analysis indicates whether more emergency capacity is necessary. We discuss potential applications in managing emergency surgery theatres.