Introduction: Following the negative results of the EC-IC Bypass Study and more recently the Carotid Occlusion Surgery Study (COSS), the continued role of EC-IC bypass for the treatment of cerebrovascular disease has been questioned. Procedures recorded in the Nationwide Inpatient Sample between 1992-2001 have previously been analyzed. We herein report an update analyzing data for the following decade.
Methods: We performed a retrospective study of admissions from 2000-2009 in the Nationwide Inpatient Sample. We assessed trends in safety, quality, and value of care with primary outcomes of mortality, discharge proportion, length of stay (LOS), and hospital charges.
Results: We identified 6,027 EC-IC bypass patients treated in US hospitals. The annual nationwide caseload increased significantly from 444 cases/yr (2000-2004) to 761 cases/yr (2005-2009) (p=0.008) with moyamoya emerging as the predominant diagnosis in the second half of the decade. The number of hospitals at which bypass was performed remained stable, but there was a shift towards a larger proportion being treated at high-volume centers (p<0.001). There was a concomitant decrease in mortality (3.7% to 1.6%, p<0.001), LOS (11 to 9 days, p<0.001), and an increase in routine discharge proportion (64% to 72%, p<0.001). Rates of hemorrhage/infarction and hematoma formation decreased (p=0.006 and p=0.001), although the rate of deep venous thrombosis/pulmonary embolus increased (p=0.004). Mean total charges increased from $82,839 to $127,320, which is a 34% inflation-adjusted increase. Multivariate analysis revealed a decrease in mortality in the second half of the study (p=0.05, OR 0.42) adjusting for age, gender, race, geographic region, admission type, hospital volume, medical comorbidity score, and primary diagnosis.
Conclusions: During the study interval the US annual caseload for EC-IC bypass increased significantly. Charges increased by one-third over the study period, and there was a trend toward progressive concentration of EC-IC bypass admissions at the highest volume centers that was accompanied by a decline in mortality rates and length of stay, and higher discharge proportion. This is a reversal of the prior decade’s trends, and may reflect a shift in the treatment population and centralization of care.
Patient Care: This will help practitioners understand shifting indications and trends in the use of bypass.
Learning Objectives: To identify trends in the use of extracranial-intracranial bypass over the past decade.