Hospital volume, calendar age, and short term outcomes in patients undergoing repair of abdominal aortic aneurysms: the Ontario experience, 1988-92.

Abstract

Objective -To determine, for abdominal aortic aneurysm surgery, whether a previously reported relationship between hospital case volume and mortality rate was observed in Ontario hospitals and to assess the potential impact ofage on the mortality rate for elective surgery. Design -Population based observational study using administrative data. confidence intervals 0-88, 0.99) and 0-29 days reduction (95% CI -0-22, -0-35) in postoperative in-hospital stay. Female sex (OR 1-53, 95% CI 1-08, 2-18) and transfer from another acute care hospital (OR 4-37, 95% CI 2-62, 7-29) were associated with increased case fatality rates among patients in the unruptured category. For ruptured cases, neither the case fatality rate nor postoperative in-hospital stay were significantly related to hospital volume. The case fatality rates increased linearly and substantially with advancing age both for unruptured and ruptured aneurysms, and the excess risk of postoperative death in ruptured as compared to unruptured aneurysms was substantially higher in older patients. Conclusion -The relationship between hospital volume and mortality or morbidity was very modest and observed only for elective surgery. Case fatality rates in patients with ruptured abdominal aortic aneurysms remained 10 times higher than for patients with unruptured abdominal aortic aneurysms, despite improvements in overall mortality in comparison to previously published data. More effective detection of aneurysms, including elective repair for those once considered "high risk" older patients, might further reduce the toll from ruptured aortic aneurysms.

Abdominal aortic aneurysm in women

“…In patients evaluated for the UK Small Aneurysm Trial, the rate of AAA rupture was three times higher in women than in men after adjustment for age, body size, and initial AAA diameter. 4 In several large population-based series investigators have reported the postoperative mortality rate after AAA repair to be 30% to 50% higher in women than in men, [5][6][7][8] though smaller studies have reported no difference. 9,10 There has also been recent evidence that AAA is more closely associated with stroke in women 11,12 and that women with AAA may have a higher frequency of suprarenal aortic involvement, 13,14 but these findings require confirmation.…”

ACC/AHA 2005 Guidelines for the Management of Patients With Peripheral Arterial Disease (Lower Extremity, Renal, Mesenteric, and Abdominal Aortic): Executive Summary A Collaborative Report From the American Association for Vascular Surgery/Society for Vascular Surgery,⁎⁎AAVS/SVS when Guideline initiated, now merged into SVSSociety for Cardiovascular Angiography and Interventions, Society for Vascular Medicine and Biology, Society of Interventional Radiology, and the ACC/AHA Task Force on Practice Guideline

“…Other studies have reconfirmed these observations with respect to hospital volume (341,348), surgeon experience (336), or both (349). Manheim et al (338) and Dimick et al (347) have estimated that the operative mortality rate for elective aneurysm repair is reduced by approximately 50% in high-volume hospitals in the U.S., and Wen et al (335) have calculated that there is a 6% reduction in the relative odds for death with every 10 additional elective cases that are added to the annual hospital volume in Ontario. Pearce et al (340) discovered that a doubling of the annual surgeon volume was associated with an 11% reduction in the relative risk for death after aortic aneurysm repair in Florida, and Dardik et al (339) have determined that hospital charges are significantly lower in conjunction with the repair of either intact or ruptured aortic aneurysms by high-volume surgeons in Maryland.…”

ACC/AHA 2005 Guidelines for the Management of Patients With Peripheral Arterial Disease (Lower Extremity, Renal, Mesenteric, and Abdominal Aortic): A Collaborative Report from the American Association for Vascular Surgery/Society for Vascular Surgery,⁎Society for Cardiovascular Angiography and Interventions, Society for Vascular Medicine and Biology, Society of Interventional Radiology, and the ACC/AHA Task Force on Practice Guidelines (Writing Committee to Develop Guidelines for the Management of Patients

“…, or both(1112).Manheim et al (1091) andDimick et al (1078) have estimated that the operative mortality rate for elective aneurysm repair is reduced by approximately 50% in highvolume hospitals in the United States, and Wen et al(1088) have calculated that there is a 6% reduction in the relative odds for death with every 10 additional elective cases that are added to the annual hospital volume in Ontario, Canada. Pearce et al(1093) discovered that a doubling of the annual surgeon volume was associated with an 11% reduction in the relative risk for death after aortic aneurysm repair in Florida, and Dardik et al(1092) have determined that hospital charges are significantly lower in conjunction with the repair of either intact or ruptured aortic aneurysms by high-volume surgeons in Maryland.5.2.6.1.4.…”