Does an acute care surgery model decrease the rate of negative appendicectomy in the Australian experience: A systematic review and meta-analysis

Background

Australia performs more appendicectomies per capita than nearly any other country. The surgical specialty responsible for performing appendicectomies in Australia, General Surgery, has recently undergone a paradigm shift away from traditional models of care and towards Acute Surgical Unit (ASU) models. ASUs are defined by the presence of a dedicated emergency general surgeon and the separation of elective and emergency surgical caseload. The aim of this meta-analysis is to determine the effect of care model type on the rate of negative appendicectomy, as well as other clinical outcomes pertaining to the appendicectomy patient.

Methods

A comprehensive literature search of Medline, Embase and Cochrane library was performed to identify studies investigating the effect of ASU care model on the outcomes of appendicectomy for Australian and New Zealand patients. These studies were required to have a comparison to a pre-existing or geographically related traditional care cohort. The PRISMA guidelines were used to identify, screen and analyse papers. Random-effects methods were used to perform a meta-analysis of negative appendicectomy rate and other relevant outcomes. Results were reported in either odds ratio or weighted mean difference.

Results

Thirteen studies meeting the inclusion criteria were identified describing the outcomes of 8787 patients undergoing appendicectomy in Australian and New Zealand hospitals. There was no effect on negative appendicectomy rate between the ASU and traditional cohorts (OR: 1.10, CI: 0.944-1.262, p-value 0.20). Furthermore, no significant effect on time-to-theatre (WMD: 1.107, CI: 0.332 – 2.882, p-value 0.22), length of stay (MD: 0.563, CI: 0 – 1.135, p-value 0.13) or complication rate (OR: 0.872, CI: 0.596 – 1.148, p-value 0.36) was observed between the two cohorts.

Conclusion

Rates of negative appendicectomy in Australia are similar in both ASU and traditional model cohorts. Significant improvements in appendicectomy outcomes seen under an ASU model in international data, or in data for other emergency conditions, have not been replicated on this meta-analysis of the Australian literature.