Temporal Trends in the Investigation, Management and Outcomes of Acute Appendicitis over 15 Years in the North of England: A Retrospective Cohort Study

Background Acute appendicitis is a common surgical emergency with an estimated lifetime prevalence of 8.6% for males and 6.7% for females. Despite the frequency of presentation, considerable variation in clinical practice exists. Our study aimed to explore temporal trends in the investigation, treatment and outcomes for patients with appendicitis between 2002 and 2016. Methods Data collected included all patients aged >= 16 years across the NHS trusts in Northern England between 01/01/2002 and 31/12/2016 diagnosed with appendicitis. Patient demographics, co-morbidity and management strategies were included. Outcomes of interest were length of stay and inpatient mortality. Results Over a 15 years period, 22,137 patients were admitted with acute appendicitis. A consistent male preponderance (n = 11,952, 54%) was observed, and median age increased over time (2002-2006: 36.4 vs. 2012-2016: 39.5, p < 0.001). Comorbidity of patients also increased (p < 0.001) in recent years. Computed tomography (CT) use increased from 0.8 to 21.9% (p < 0.001) over the study period. Following CT scanning, there was a longer time to theatre (1.22 vs. 0.70 days, p < 0.001), and patients were more frequently managed non-operatively (23.8% vs. 5.7%, p < 0.001). The utilisation of laparoscopic approaches significantly increased from 4.1 to 70.4% (p < 0.001). Laparoscopic patients had a shorter median length of stay (2.97 days) when compared with open surgery (4.44 days) or non-operative (6.19 days) patients. The 30-day mortality rate was 0.33% overall and decreased with time (p = 0.004). Conclusions CT and laparoscopic surgery are increasingly utilised in the management of appendicitis. Along with other advances in clinical practice, they have led to reduced lengths of stay and mortality.