K. S. Ng1, Y. Y. Lee1, M. K. Suen1, N. Nassar2, M. A. Gladman1 1Sydney Medical School – Concord, University Of Sydney,Academic Colorectal Unit,Sydney, NSW, Australia 2The Kolling Institute, University Of Sydney,Clinical And Population Perinatal Health Research,Sydney, NSW, Australia
Introduction:
Previous population-based outcomes studies of colorectal surgery have been limited to patients with cancer and / or procedures performed only on the colon and / or rectum. Given that colorectal practice encompasses other diseases that affect the hindgut (e.g. diverticular disease) or the midgut (e.g. Crohn’s disease), an accurate appreciation of overall outcomes of major colorectal procedures is currently unknown. Therefore, we aimed to determine the statewide outcomes of patients undergoing major colorectal surgery on the mid and hindgut in the last decade in Australia.
Methods:
A population-based study was conducted using longitudinally linked statutory Admitted Patient Data Collection (hospital data) and Registered Deaths in New South Wales, Australia. The study population was defined as all patients undergoing major colorectal procedures on the mid and hindgut for colorectal disease in 2000-2010. These were identified via relevant procedural and diagnostic codes based on the Australian Classification of Healthcare Interventions and International Classification of Diseases version 10- Australian Modification (ICD10-AM), respectively. Descriptive statistics, 28-day readmission rate and 30-day and 1-year mortality rates, both overall and stratified by age and sex were calculated.
Results:
A total of 109,149 major colorectal procedures were performed in 89,053 patients during the study period. Over one-quarter (n=30,287; 27.7%) of patients were >75years, 47.2% were male and 11.1% (n=12,076) had a Charlson co-morbidity score ≥3. Almost two-thirds (63.5%) of all procedures were performed on the colon and / or rectum. Obstruction / adhesions and cancer accounted for more than half of all indications for surgery. The 28-day readmission rate was 22.7% (n=24,818) and overall 30-day and 1-year mortality was 6.1% (n= 5,451) and 13.5% (n=12,041), respectively. Compared with females, males had consistently higher 30-day (6.5 versus 5.8 deaths per 100 patients) and 1-year (42.5 versus 38.0 per 100 patients) mortality rates. Overall, 30-day mortality rates increased with age being 2.8, 8.0, 13.8 and 21.8 per 100 patients aged <70, 70-79, 80-89 and 90+ years, respectively. Similarly, 1-year mortality rates increased with age being 7.8, 17.4, 26.3 and 39.3 years per 100 patients for <70, 70-79, 80-89 and 90+ years, respectively.
Conclusion:
This, the first population-based study of outcomes following major colorectal surgery, including procedures on the mid and hindgut, demonstrates that overall Australian mortality rates are similar to those of other countries. However, findings reveal colorectal surgeons are facing an increasingly co-morbid and aged population, where the mortality is substantially higher. This suggests that new models of perioperative care need to be considered for colorectal surgery, especially for “high risk” patients.