SS26. Population-Based Analysis of Inpatient Vascular Procedures: Predicting Future Workload and Implications for Training
ABSTRACT The purpose of this study was to analyze the trend in inpatient vascular procedures in the United States over the past decade and predict the future demand for vascular surgeons.
The Healthcare Cost and Utilization Project Nationwide Inpatient Sample was queried to determine the weighted national estimates of inpatient vascular procedures performed on adult patients (age ≥ 18) between 1997 and 2008. Using population estimates from the United States Census Bureau, the per capita rates of inpatient procedures were calculated for age-specific groups (18-64 years, 65-84 years, and ≥ 85 years). The change in per capita rates over the past decade along with population forecasts were used to predict future workload.
There was a net increase of 22% from 971,046 inpatient vascular procedures for all adults in 1997 to 1,188,332 in 2008. During the same time period, the adult population increased by 16% from 198 to 230 million. The age-stratified per capita rates of all vascular procedures were +21% for age 18 to 64; -4% for age 65 to 84; and +18% for age ≥ 85. This resulted in a net increase of 5% (490 to 515 procedures per 100,000 capita) in the per capita rate for all adults. Based on the assumption that trends in age-specific rates remain constant, there is a predicted inpatient workload increase (compared to 2008) of 18% by 2015, 34% by 2020, and 72% by 2030. The vascular workload is predicted to more than double by the year 2040.
Despite a conservative approach of using a population-based analysis of only inpatient procedures, there is a dramatic increase in the predicted vascular workload for the future. The vascular surgery training process will need to adapt to ensure an adequate number of fellowship-trained vascular surgeons is available to provide quality vascular care in the future.
SourceAvailable from: Men Zhu[Show abstract] [Hide abstract]
ABSTRACT: Open vascular reconstructions frequently fail due to the development of recurrent disease or intimal hyperplasia (IH). This paper reports a novel drug delivery method using a rapamycin-loaded poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs)/pluronic gel system that can be applied periadventitially around the carotid artery immediately following the open surgery. In vitro studies revealed that rapamycin dispersed in pluronic gel was rapidly released over 3 days whereas release of rapamycin from rapamycin-loaded PLGA NPs embedded in pluronic gel was more gradual over 4 weeks. In cultured rat vascular smooth muscle cells (SMCs), rapamycin-loaded NPs produced durable (14 days versus 3 days for free rapamycin) inhibition of phosphorylation of S6 kinase (S6K1), a downstream target in the mTOR pathway. In a rat balloon injury model, periadventitial delivery of rapamycin-loaded NPs produced inhibition of phospho-S6K1 14 days after balloon injury. Immunostaining revealed that rapamycin-loaded NPs reduced SMC proliferation at both 14 and 28 days whereas rapamycin alone suppressed proliferation at day 14 only. Moreover, rapamycin-loaded NPs sustainably suppressed IH for at least 28 days following treatment, whereas rapamycin alone produced suppression on day 14 with rebound of IH by day 28. Since rapamycin, PLGA, and pluronic gel have all been approved by the FDA for other human therapies, this drug delivery method could potentially be translated into human use quickly to prevent failure of open vascular reconstructions.PLoS ONE 02/2014; 9(2):e89227. DOI:10.1371/journal.pone.0089227 · 3.53 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: Intimal hyperplasia produces restenosis (re-narrowing) of the vessel lumen following vascular intervention. Drugs that inhibit intimal hyperplasia have been developed, however there is currently no clinical method of perivascular drug-delivery to prevent restenosis following open surgical procedures. Here we report a poly(ε-caprolactone) (PCL) sheath that is highly effective in preventing intimal hyperplasia through perivascular delivery of rapamycin. We first screened a series of bioresorbable polymers, i.e., poly(lactide-co-glycolide) (PLGA), poly(lactic acid) (PLLA), PCL, and their blends, to identify desired release kinetics and sheath physical properties. Both PLGA and PLLA sheaths produced minimal (<30%) rapamycin release within 50days in PBS buffer. In contrast, PCL sheaths exhibited more rapid and near-linear release kinetics, as well as durable integrity (>90days) as evidenced in both scanning electron microscopy and subcutaneous embedding experiments. Moreover, a PCL sheath deployed around balloon-injured rat carotid arteries was associated with a minimum rate of thrombosis compared to PLGA and PLLA. Morphometric analysis and immunohistochemistry revealed that rapamycin-loaded perivascular PCL sheaths produced pronounced (85%) inhibition of intimal hyperplasia (0.15±0.05 vs 1.01±0.16), without impairment of the luminal endothelium, the vessel's anti-thrombotic layer. Our data collectively show that a rapamycin-loaded PCL delivery system produces substantial mitigation of neointima, likely due to its favorable physical properties leading to a stable yet flexible perivascular sheath and steady and prolonged release kinetics. Thus, a PCL sheath may provide useful scaffolding for devising effective perivascular drug delivery particularly suited for preventing restenosis following open vascular surgery.Journal of Controlled Release 05/2014; DOI:10.1016/j.jconrel.2014.05.017 · 7.26 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: The most common and significant morbidity and mortality of vascular surgical procedures remain coronary artery disease, arrhythmia, and heart failure. Cardiac evaluation and medical optimization provide the groundwork for best medical practice in an otherwise high-risk surgical population. The goal of this study is to review the most current literature and guidelines for evaluating patients prior to vascular surgical interventions. From this, we have made our own recommendations regarding both the preoperative and perioperative management of vascular surgical patients.Current Opinion in Cardiology 09/2014; 29(6). DOI:10.1097/HCO.0000000000000117 · 2.59 Impact Factor