Cannulation Strategy for Extracorporeal Membrane Oxygenation Does Not Influence Total Hospital Cost.

BACKGROUND: The Center for Medicare and Medicaid Services decreased reimbursement rates for peripheral venoarterial (VA) extracorporeal membrane oxygenation (ECMO) and venovenous (VV) ECMO procedures in October 2018. Limited data are available describing hospital costs and clinical resources required to support ECMO patients. METHODS: All patients supported on ECMO at our institution between March 2017 and October 2018 were identified. Exclusion criteria were cannulation at referring hospitals, organ transplant recipients, and temporary right ventricular support. The cohort was stratified by the initial cannulation strategy. Outcomes were total hospital cost and clinical resource utilization. RESULTS: There were 29 patients supported on central VA, 72 on peripheral VA, and 37 on VV ECMO. Survival at 30 days was 48% for central vs 37% for peripheral vs 51% for VV. Hospital costs were $187,848 for central vs $178,069 for peripheral vs $172,994 for VV (P = .91). Mean hospital stay was 25.8 days for central vs 21.5 days for peripheral vs 26.2 days for VV (P = .49). Mean intensive care unit stay was 14.1 days for central vs 12.8 days for peripheral vs 7.7 days for VV (P = .25). Mean length of ECMO support was 6.5 days for central vs 6.2 days for peripheral vs 7.8 days for VV (P = .38). Mean ventilator time was 13.0 days for central vs 8.2 days for peripheral vs 10.0 days for VV (P = .06). Hemodialysis was used in 41% central patients, 47% peripheral, and 41% VV (P = .75). Theoretical ECMO reimbursement losses ranged from $1,970,698 to $5,648,219 annually under 2018 Center for Medicare and Medicaid Services rates. CONCLUSIONS: ECMO cannulation strategy has minimal impact on resource utilization and hospital cost.

Below-Knee Amputation Failure and Poor Functional Outcomes Are Higher Than Predicted in Contemporary Practice.

OBJECTIVE: The perceived functional benefit of below-knee amputation (BKA) must be carefully weighed against the need for potential reinterventions. This study sought to examine the contemporary clinical and functional outcomes of patients undergoing BKA in the endovascular era. METHODS: All patients who underwent BKA from January 2008 to December 2014 at a single tertiary medical center were retrospectively reviewed. Demographics, comorbidities, ambulation status, and transcutaneous oximetry (TcPO2) values were recorded. Study end points included freedom from conversion to above-knee amputation (AKA), freedom from conversion to AKA or death, BKA healing, and ambulation. Statistical modeling was performed to determine associations with BKA failure. RESULTS: Over the study interval, 130 limbs underwent BKA in 120 patients. Transcutaneous oximetry studies were obtained in 65% (n = 85). Thirty-eight percent (n = 46) of all BKA patients went on to heal and ambulate. Twenty-five percent (n = 33) required reintervention, 24 with conversion to AKA, and 9 with BKA revision. One-year freedom from conversion to AKA was 76% and was decreased among those with lower TcPO2 levels (60% TcPO2 <40 vs 81% TcPO2 ≥40; P = .04). One-year composite freedom from conversion to AKA/death was 60% and was decreased among those with lower TcPO2 readings (39% TcPO2 <40 vs 69% TcPO2 ≥40; P = .01). CONCLUSION: Despite a perceived functional bias toward knee salvage at the time of major amputation, most patients failed to postoperatively ambulate. Those with decreased TcPO2 levels (<40 mm Hg) have a 2-fold higher risk of AKA conversion or death, while nearly one-fourth of all BKA patients will succumb to the same fate irrespective of TcPO2. This suggests that many BKA patients in the endovascular era fail to derive the perceived benefit of knee salvage at the time of their index amputation. These findings highlight the need for careful patient selection and for a shared decision-making model in this frail population.

Lesion complexity drives the cost of superficial femoral artery endovascular interventions.

OBJECTIVE: Patients who undergo endovascular treatment of superficial femoral artery (SFA) disease vary greatly in lesion complexity and treatment options. This study examined the association of lesion severity and cost of SFA stenting and to determine if procedure cost affects primary patency at 1 year. METHODS: A retrospective record review identified patients undergoing initial SFA stenting between January 1, 2010, and February 1, 2012. Medical records were reviewed to collect data on demographics, comorbidities, indication for the procedure, TransAtlantic Inter-Society Consensus (TASC) II severity, and primary patency. The interventional radiology database and hospital accounting database were queried to determine cost drivers of SFA stenting. Procedure supply cost included any item with a bar code used for the procedure. Associations between cost drivers and lesion characteristics were explored. Primary patency was determined using Kaplan-Meier survival curves and a log-rank test. RESULTS: During the study period, 95 patients underwent stenting in 98 extremities; of these, 61% of SFA stents were performed for claudication, with 80% of lesions classified as TASC II A or B. Primary patency at 1 year was 79% for the entire cohort. The mean total cost per case was $10,333. Increased procedure supply cost was associated with adjunct device use, the number of stents, and TASC II severity. Despite higher costs of treating more complex lesions, primary patency at 1 year was similar at 80% for high-cost (supply cost >$4000) vs 78% for low-cost (supply cost <$4000) interventions. CONCLUSIONS: SFA lesion complexity, as defined by TASC II severity, drives the cost of endovascular interventions but does not appear to disadvantage patency at 1 year. Reimbursement agencies should consider incorporating disease severity into reimbursement algorithms for lower extremity endovascular interventions.

Retrospective review of superficial femoral artery stenting in diabetic patients: thiazolidinedione use may decrease reinterventions.

BACKGROUND: Diabetics are known to have inferior outcomes following peripheral vascular interventions. Thiazolidinediones are oral diabetic agents which improve outcomes following coronary bare metal stenting. No studies have been performed evaluating thiazolidinedione use and outcomes following lower extremity endovascular interventions. We hypothesize that diabetic patients taking thiazolidinediones at the time of primary superficial femoral artery (SFA) stenting have fewer reinterventions. METHODS: A retrospective review was performed to identify diabetic patients undergoing primary SFA stenting. The unit of analysis was the extremity. The primary outcome was freedom from target lesion revascularization stratified by thiazolidinedione use, evaluated by Kaplan Meier curves and a log rank test. A Cox proportional hazards model was constructed to determine variables associated with freedom from target lesion revascularization. RESULTS: SFA stents were placed in 138 extremities in 128 diabetic patients between August 1, 2001 and July 15, 2012. Twenty-four patients were taking thiazolidinediones at the time of SFA stenting. All patients taking thiazolidinediones had TASC A or B lesions. Twenty-seven extremities in the non-thiazolidinedione group had TASC C or D lesions and were excluded to control for disease severity. Freedom from target lesion revascularization was significantly higher in diabetics taking thiazolidinediones at 2 years, 88.5% vs. 59.4%, P = 0.02, SE < 10%. Cox modeling identified a protective trend for thiazolidinedione use (thiazolidinedione use HR 0.33, 95% CI 0.09-1.13), whereas critical limb ischemia and insulin use were associated with trends for worse freedom from target lesion revascularization. CONCLUSIONS: This pilot, translation study demonstrates that diabetic patients taking thiazolidinediones at the time of primary SFA stenting have decreased reintervention rates at 2 years. These results may be explained by higher adiponectin levels or other anti-inflammatory effects in patients taking thiazolidinedione. National and regional quality improvement registries should consider collecting information regarding specific diabetic regimens and use of PPAR agonists such as cilostazol and fibrates.

Midterm cost and effectiveness of thoracic endovascular aortic repair versus open repair.

BACKGROUND: Thoracic endovascular aneurysm repair (TEVAR) has been rapidly introduced as a primary treatment modality for thoracic aortic diseases with limited data available on midterm to late-term outcomes. METHODS: A retrospective single institution study comparing hospital and midterm outcomes and costs for TEVAR versus open elective repair of descending thoracic aneurysms was conducted. Fifty-seven patients were included between 2005 and 2007 (TEVAR=28; open=29) and were followed until May 2010. RESULTS: Patients in the TEVAR group were older (73.2 versus 62.3 years; p<0.001). Hospital mortality was higher in the open repair group (10.3% versus 3.6%; p=0.611). There was no statistical difference in stroke, paraparesis or paralysis, sepsis, or renal failure; however, a composite major adverse event variable showed a higher complication with open repair versus TEVAR (37.9% versus 14.3%; p=0.043). Mean follow-up was 42.6 months for open repair versus 26.9 for TEVAR (p=0.002). Kaplan-Meier survival analysis showed the initial survival benefit for TEVAR was lost in less than 6 months; however, the difference did not reach statistical significance during follow-up (log-rank test p=0.232). Mean surveillance imaging costs for a TEVAR patient were $1,800.38 higher than for an open patient at 2 years. Compliance of TEVAR patients with follow-up imaging was 78%, 64%, 50%, and 42% at 1, 6, 12, and 24 months, respectively, and was even lower in those not registered in device trials. CONCLUSIONS: Patients in the TEVAR group had favorable early outcomes; however, midterm survival was reduced secondary to comorbidities. This study raises concern for the ongoing costs of surveillance imaging in TEVAR as well as patient compliance with follow-up.

Practice patterns for thoracic aneurysms in the stent graft era: health care system implications.

BACKGROUND: The US Food and Drug Administration approved the first thoracic aneurysm endograft in 2005. However, because the United States lacks a thoracic aneurysm endovascular repair registry, implications of Food and Drug Administration endograft approval on surgical management of thoracic aneurysms in clinical practice are unknown. METHODS: Retrospective review of thoracic aneurysm repair rates for 2000 to 2007 and analysis of patient characteristics and complications for 2006 and 2007 cohorts uses the National Inpatient Sample. International Classification of Diseases, 9th Revision codes were used to identify unruptured descending thoracic aneurysm cases undergoing either thoracic endovascular aortic repair (39.73) or open repair (38.45). RESULTS: Thoracic aneurysm open repair averaged 3.3 per million from 2000 to 2002 and increased to 5.6 per million in 2003 with introduction of 16 slice computed tomographic scanners. In 2005 endovascular repair was 1.2 repairs per million, which increased dramatically to 6.1 repairs per million in 2006. In 2007, endovascular repair decreased to 4.8 repairs per million while the open repair rate was 3.1 repairs per million. The 2006 and 2007 open repair cohorts had more favorable baseline characteristics compared with the endovascular cohort. Open repair mortality was significantly greater than endovascular mortality in 2006 (estimated relative risk, 8.48; 95% confidence interval 3.03 to 23.75), but not in 2007 (estimated relative risk, 0.71; 95% confidence interval 0.12 to 4.24). Length of stay was greater for open repair in 2006 and 2007. CONCLUSIONS: Thoracic endovascular aortic repair has been rapidly adopted in the United States resulting in increased treatment of thoracic aortic aneurysms. Despite older age and comorbidities, endovascular repair had better outcomes and shorter hospital stays.