Variability in hospital costs for carotid artery revascularization

Objective

The objective of this study was to understand drivers of cost for carotid endarterectomy (CEA) and carotid artery stenting (CAS) and to compare variation in cost among cases performed by vascular surgery (VS) with other services (OSs).

Methods

We collected internal hospital claims data for CEA and CAS between September 2013 and August 2015 and performed a financial analysis of all hospital costs including room accommodations, medications, medical and surgical supplies, imaging, and laboratory tests. Cases were stratified by presence of symptoms and procedure type, and costs of procedures performed by VS were compared with those performed by OSs.

Results

The cohort comprised 144 patients (78 asymptomatic, 66 symptomatic; 44 CAS, 100 CEA) receiving unilateral revascularization. VS (24 CAS, 70 CEA) and neurosurgery and neurointerventional radiology services (20 CAS, 30 CEA) performed all procedures. Age (71 ± 9 years vs 70 ± 11 years; P = .8) and length of stay (1.7 ± 2.1 days vs 2.2 ± 2.4 days; P = .73) were similar for VS and OSs. Symptoms were present before revascularization for 46% and were more commonly treated by OSs (78% vs 29%; P < .001). Case mix index was similar after stratifying by symptoms (asymptomatic, 1.28 ± 0.35 vs 1.39 ± 0.42 [P = .5]; symptomatic, 1.66 ± 0.73 vs 1.82 ± 0.81 [P = .9]). The largest cost components were operating room (OR)-related costs, beds, and supplies, together accounting for 76% of costs. Asymptomatic patients had 37% lower average hospital costs. For asymptomatic CAS, average index hospitalization cost was 17% less for VS compared with OSs because of 78% lower intensive care unit costs, 44% lower OR-related costs, 40% lower medication costs, and 24% lower cardiac testing costs. VS had 22% higher supply costs. For asymptomatic CEA, average index hospitalization costs were 22% lower for VS, driven by lower OR-related costs (28%), medications (28%), imaging (62%), and neurointerventional monitoring (64%). Costs were 38% higher for CAS vs CEA. For symptomatic CAS, costs were similar for both groups. For symptomatic CEA, total costs were 14% lower for VS compared with OSs, driven by 25% lower OR-related costs, 62% lower neurointerventional monitoring, 20% step-down beds, and 28% lower supply costs (and counterbalanced by 117% higher intensive care unit costs).

Conclusions

VS average hospital costs were lower for asymptomatic CAS and all CEAs compared with OSs. Drivers of higher cost appear to be attributed to variation in physicians' practice as well as patients' complexity, affording an opportunity to reduce cost by establishing standard practices when appropriate.