Frequency of surgical treatment and related hospital procedures in the UK: a national ecological study using hospital episode statistics

BACKGROUND: Despite evidence of high activity, the number of surgical procedures performed in UK hospitals, their cost and subsequent mortality remain unclear. METHODS: Time-trend ecological study using hospital episode data from England, Scotland, Wales and Northern Ireland. The primary outcome was the number of in-hospital procedures, grouped using three increasingly specific categories of surgery. Secondary outcomes were all-cause mortality, length of hospital stay and healthcare costs according to standard National Health Service tariffs. RESULTS: Between April 1, 2009 and March 31, 2014, 39 631 801 surgical patient episodes were recorded. There was an annual average of 7 926 360 procedures (inclusive category), 5 104 165 procedures (intermediate category) and 1 526 421 procedures (restrictive category). This equates to 12 537, 8073 and 2414 procedures per 100 000 population per year, respectively. On average there were 85 181 deaths (1. 1%) within 30 days of a procedure each year, rising to 178 040 deaths (2. 3%) after 90 days. Approximately 62. 8% of all procedures were day cases. Median length of stay for in-patient procedures was 1. 7 (1. 3-2. 0) days. The total cost of surgery over the 5 yr period was £54. 6 billion (104. 4 billion), representing an average annual cost of £10. 9 billion (inclusive), £9. 5 billion (intermediate) and £5. 6 billion (restrictive). For each category, the number of procedures increased each year, while mortality decreased. One-third of all mortalities in national death registers occurred within 90 days of a procedure (inclusive category). CONCLUSIONS: The number of surgical procedures in the UK varies widely according to definition. The number of procedures is slowly increasing whilst the number of deaths is decreasing.