The role of facility-based surgical services in addressing the national burden of disease in New Zealand: an index of surgical incidence based on country-specific disease prevalence

Abstract

Background

Surgery is a crucial component of health systems, yet its actual contribution has been difficult to define. We aimed to link use of national hospital service with national epidemiological surveillance data to describe the use of surgical procedures in the management of a broad spectrum of conditions.

Methods

We compiled Australian Modification-International Classification of Diseases-10 codes from the New Zealand National Minimum Dataset, 2008–11. Using primary cause of admission, we aggregated admissions to 91 hospitals into 119 disease states and 22 disease subcategories of the WHO Global Health Estimate (GHE). We queried each admission for any surgical procedure in a binary manner to determine the frequency of admitted patients whose care required surgery. Surgical procedures were defined as requiring general or neuroaxial anaesthesia. We then divided the volume of surgical cases by counts of disease prevalence from the GBD 2010 to determine surgical incidence. This study was approved by the University of Otago Human Ethics Committee (Health; Reference Number HD14/42). Raw data was only handled by coauthors with direct affiliation with the New Zealand Ministry of Health.

Findings

Between 2008 and 2011, there were 1 108 653 hospital admissions with 275 570 associated surgical procedures per year. Surgical procedures were associated with admissions for all 22 GHE disease subcategories and 116 of 119 GHE disease states (excluding intestinal nematode infections, iodine deficiency, and vitamin A deficiency). The subcategories with the largest surgical case volumes were unintentional injuries (48 073), musculoskeletal diseases (38 030), and digestive diseases (27 640), and the subcategories with the smallest surgical case volumes were nutritional deficiencies (13), neonatal conditions (204), and infectious and parasitic diseases (982). Surgical incidence ranged widely by individual disease states with the highest in other neurological conditions, abortion, appendicitis, obstructed labour, and maternal sepsis.

Interpretation

This study confirms previous research that surgical care is required across the entire spectrum of GHE disease subcategories, showing the crucial role of operative intervention in health systems. Surgical incidence might be useful as an index to estimate the need for surgical procedures in other populations.

Funding

None.