Provider caseload volume and short-term outcomes following colorectal surgeries in New Brunswick: a provincial-level cohort study

Provider caseload volume and short-term outcomes following colorectal surgeries in New Brunswick: a provincial-level cohort study

Can J Surg 2020;63(5):E475-E482 | Full Text | PDF | Appendix

Dan L. Crouse, PhD; Jonathan Boudreau, MSc; Philip S.J. Leonard, PhD; Keith Pawluk, MD; James T. McDonald, PhD

Abstract

Background: American studies have shown that higher provider and hospital volumes are associated with reduced risk of mortality following colorectal surgical interventions. Evidence from Canada is limited, and to our knowledge only a single study has considered outcomes other than death. We describe associations between provider surgical volume and all-cause mortality and postoperative complications following colorectal surgical interventions in New Brunswick.

Methods: We used hospital discharge abstracts linked to vital statistics, the provincial cancer registry and patient registry data. We considered all admissions for colorectal surgeries from 2007 through 2013. We used logistic regression to identify odds of dying and odds of complications (from any of anastomosis leak, unplanned colostomy, intra-abdominal sepsis or pneumonia) within 30 days of discharge from hospital according to provider volume (i.e., total interventions performed over the preceding 2 years) adjusted for personal, contextual, provider and hospital characteristics.

Results: Overall, 9170 interventions were performed by 125 providers across 18 hospitals. We found decreased odds of experiencing a complication following colorectal surgery per increment of 10 interventions performed per year (odds ratio 0.94, 95% confidence interval 0.91–0.96). We found no associations with mortality. Associations remained consistent across models restricted to cancer patients or to interventions performed by general surgeons and across models that also considered overall hospital volumes.

Conclusion: Our results suggest that increased caseloads are associated with reduced odds of complications, but not with all-cause mortality, following colorectal surgery in New Brunswick. We also found no evidence of volume having differential effects on outcomes from colon and rectal procedures.

Résumé

Contexte : Des études américaines ont montré que le volume d’activité des chirurgiens et des hôpitaux est inversement proportionnel au risque de mortalité après la chirurgie colorectale. Les données pour le Canada sont limitées, et à notre connaissance, une seule étude a porté sur d’autres paramètres que le décès. Nous avons décrit les liens entre volume d’activité des chirurgiens et mortalité de toute cause/complications postopératoires après la chirurgie colorectale au Nouveau-Brunswick.

Méthodes : Nous avons utilisé les registres de congés des hôpitaux reliés aux données de la Statistique de l’état civil, du registre provincial du cancer et du registre des patients. Nous avons recensé toutes les admissions pour chirurgie colorectale de 2007 à 2013. Nous avons utilisé la régression logistique pour établir le risque de décès et le risque de complications (fuite anastomotique, colostomie non planifiée, infection intra-abdominale ou pneumonie) dans les 30 jours suivant le congé de l’hôpital par rapport au volume d’activité des chirurgiens (c.-à-d., interventions totales des 2 années précédentes) ajusté en fonction des caractéristiques individuelles et contextuelles, propres aux chirurgiens et aux hôpitaux.

Résultats : En tout, 125 chirurgiens ont effectué 9170 interventions dans 18 hôpitaux. Nous avons observé un risque moindre de complications après la chirurgie colorectale pour chaque palier de 10 interventions effectuées annuellement (risque relatif 0,94, intervalle de confiance de 95 %, 0,91–0,96). Nous n’avons observé aucun lien avec la mortalité. Les liens sont demeurés constants, peu importe que les modèles soient restreints aux patients cancéreux ou aux interventions effectuées par des chirurgiens généraux et entre les modèles qui tenaient également compte du volume global d’activité des hôpitaux.

Conclusion : Selon nos résultats, l’augmentation du volume d’activité est associée à un risque moindre de complications, mais n’a pas de lien avec la mortalité de toute cause après la chirurgie colorectale au Nouveau-Brunswick. Nous n’avons pas non plus constaté de lien entre le volume d’activité et l’issue différentielle de la chirurgie du côlon et du rectum.


Accepted Jan. 7, 2020

Affiliations: From the Department of Sociology, University of New Brunswick, Fredericton, N.B. (Crouse); the New Brunswick Institute for Research, Data and Training, University of New Brunswick, Fredericton, N.B. (Crouse, Boudreau, Leonard, McDonald); the Department of Economics, University of New Brunswick, Fredericton, N.B. (Leonard, McDonald); and the Faculty of Medicine, Dalhousie University, Halifax, N.S. (Pawluk).

Funding: This study was supported by the Maritime SPOR SUPPORT Unit (MSSU), which receives financial support from the Canadian Institutes of Health Research, the Nova Scotia Department of Health and Wellness, the New Brunswick Department of Health, the Nova Scotia Health Research Foundation and the New Brunswick Health Research Foundation. The opinions, results and conclusions reported in this paper are those of the authors and are independent from the funding sources. No endorsement by the MSSU or the named funding partners is intended or should be inferred. This work was also supported by the New Brunswick Department of Health under a data-sharing agreement with the New Brunswick Institute for Research, Data and Training at the University of New Brunswick. The results and conclusions are those of the authors and no official endorsement by the Government of New Brunswick was intended or should be inferred.

Competing interests: None declared.

Contributors: All authors conceived the study. J. Boudreau and J. McDonald acquired the data, which D. Crouse, J. Boudreau, P. Leonard and J. McDonald analyzed. D. Crouse, J. Boudreau, P. Leonard and J. McDonald drafted the manuscript, which J. Boudreau, P. Leonard, K. Pawluk and J. McDonald critically revised. All authors gave final approval of the version to be published.

DOI: 10.1503/cjs.012319

Correspondence to: D.L. Crouse, Health Effects Institute, 75 Federal St, Suite 1400, Boston MA 02110, dan.crouse@unb.ca