Incidence and risk factors of peri-operative stroke in major non-cardiovascular, non-neurologic surgery-A retrospective register-based cohort study

Abstract

Background: Peri-operative stroke is a rare but serious surgical complication. Both overt and covert stroke, occurring in approximately 0.1% and 7% of cases, respectively, are associated with significant long-term effects and increased morbidity.

Methods: Retrospective register data for patients >18 years old, presenting for major non-cardiovascular, non-neurosurgical and non-ambulatory surgical procedures at 23 hospitals in Sweden between 2007 and 2014 was collected and linked with various quality registers. The primary outcome was stroke within 30 days from surgery. Using multivariable logistic regression, significant independent risk factors influencing the primary outcome were identified and their adjusted odds ratios (ORs) were calculated. Mortality was assessed, along with the composite score of days alive and at home within 30 days after surgery (DAH 30).

Results: In total, 318,017 patients were included, with 687 (0.22%) suffering a stroke within 30 days of surgery. The strongest significant risk factors included: increasing ASA-class (OR [95% confidence interval, CI]: 2.23 [1.53-3.36], 3.91 [2.68-5.93] and 7.82 [5.03-12.5] for ASA 2, 3 and 4, respectively) and age (OR [95% CI]: 4.47 [2.21-10.3], 9.9 [5.15-22.1], 16.3 [8.48-36.5] and 21 [10.6-48.1], for age 45-59, 60-74, 75-89 and >90, respectively), along with non-elective procedures, male gender and a history of cerebrovascular disease (OR [95%]: 2.72 [2.25-3.27]). Mortality was increased and DAH 30 was reduced in patients suffering a stroke.

Conclusions: Increasing ASA-class and age was clearly associated with an increased risk of peri-operative stroke, which in turn was associated with increased mortality and poorer outcome. Detailed pre-operative risk stratification and individualised peri-operative management could potentially improve patient-centred outcomes and, in turn, have positive implications for public health.

Keywords: DAH 30; anesthesia; general surgery; peri-operative medicine; peri-operative stroke; stroke.