Matching surgical operating capacity to demand using estimates of operating times

This paper sets out to investigate whether demand for gynaecological theatre time could be described in terms of the time required to undertake elective operations booked for surgery, and so help match the capacity to this.

A questionnaire assessed the estimates for total operation time for seven common operations, sent to surgeons, anaesthetists and nursing staff in one tertiary referral and one district general hospital (total 49 staff; response rate 58 per cent), and estimates were obtained from theatre computer logs. Average timings for each operation were then applied to cases added from clinics to the waiting list at the district general, to yield the mean demand for elective surgery, and were also applied to emergencies to estimate emergency workload. Finally these demand estimates were compared with the theatre capacity available.

The paper found no difference between the estimates of the three staff groups or between these and the theatre logs (p = 0.669), nor did it find that estimates differed between the two centers (p = 0.628). Including emergencies, the mean (95 per cent confidence intervals) demand at the district general was 2438 (1952-2924) min/week.

Although the paper modelled the variation in demand using the relevant variation in operation times, any additional variation caused by differences in booking rates from clinics over time was not nodelled. The minimum period over which data should be collected was not established.

The paper finds that the existing capacity of 1680 min/week did not match these needs and, unless it was increased, a rise in waiting lists was predictable.

The paper concludes that time estimates for scheduled operations can be better used to assess the need for surgical operating capacity than current measures of demand or capacity.