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Updated: Jan 24, 2026

Survivable Stereotaxic Surgery in Rodents
Published on: October 6, 2008
Surgery for adhesive small-bowel obstruction is associated with improved long-term survival mediated through
Ramy Behman1, Avery B Nathens, Barbara Haas
1From the Division of General Surgery, Department of Surgery (R.B., A.B.N., B.H., N.L.H., P.K.), University of Toronto; Division of General Surgery (A.B.N., B.H., N.L.H., P.K.), Sunnybrook Health Sciences Centre; Institute of Health Policy Management and Evaluation (A.B.N., B.H., N.L.H., P.P., P.K.), Interdepartmental Division of Critical Care Medicine (B.H.), University of Toronto; and Child Health Evaluative Sciences (P.P.), The Hospital for Sick Children, Toronto, Ontario, Canada.
Background:
Adhesive small-bowel obstruction (aSBO) is among the most common reasons for admission to a surgical service. While operative intervention for aSBO is associated with a lower risk of recurrence, current guidelines continue to advocate a trial of nonoperative management. The impact of the increased risk for recurrence on long-term survival is unknown. We sought to explore the potential for improved survival with operative management through the prevention of admissions for recurrence of aSBO and the associated risks.
Methods:
This is a population-based retrospective cohort study using administrative data. We identified patients admitted to hospital for their first episode of aSBO from 2005 to 2014 and created a propensity-matched cohort to compare survival of patients managed operatively with those managed nonoperatively. To test whether survival differences were mediated by recurrence prevention, a competing risk regression was used to model the subdistribution hazard of death when accounting for the risk of recurrence. An instrumental variable approach was used as a secondary analysis to compare survival while accounting for unmeasured confounding.
Results:
There were 27,904 patients admitted for their first episode of aSBO between 2005 and 2014. The mean age was 61.2 years (std dev, 13.6), and 51% were female. Operative management was associated with a significantly lower risk of death (hazard ratio, 0.80; 95% confidence interval, 0.75-0.86), which was robust to instrumental variable analyses, and a lower risk of recurrence (hazard ratio, 0.59; 95% confidence interval, 0.54-0.65). When adjusting for the risk of recurrence, operative intervention was not associated with improved survival, suggesting that the survival benefit is mediated through prevention of recurrences of aSBO.
Conclusion:
In patients admitted for their first episode of aSBO, operative intervention is associated with a significant long-term survival benefit. This survival benefit appears to be mediated through the prevention of recurrences of aSBO.
Study Type:
Retrospective cohort study.
Level Of Evidence:
Therapeutic study, Level II.
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