Evolving roles of radiologists, nephrologists, and surgeons in endovascular hemodialysis access maintenance procedures

Nationwide Trends in Catheter-Directed Therapy Utilization for the Treatment of Lower Extremity Deep Vein Thrombosis in Medicare Beneficiaries

PURPOSE

To determine overall and provider specialty trends in the use of catheter-directed therapy for lower extremity deep vein thrombosis (DVT) treatment in the Medicare population.

MATERIALS AND METHODS

Using data obtained from 2007-2017 Centers for Medicare & Medicaid Services 5% research identifiable files, all claims associated with acute and chronic lower extremity DVT were identified. The annual volume of 2 services-venous percutaneous transluminal thrombectomy (current procedural terminology [CPT] code 37187) and venous infusion for thrombolysis (CPT code 37201 from 2007 to 2012 and CPT code 37212 from 2013 to 2017)-was examined for trends in DVT intervention. Utilization rates based on region and the place of service were calculated. The results were further categorized based on primary operator type (radiology, cardiology, surgery, and other).

RESULTS

The total number of DVT interventions increased over time, with 4.27 service counts per 100,000 beneficiaries in 2007 increasing to 13.4 by 2017, a growth rate of 12.09%. Radiologists performed the majority of interventions each year, except in 2013, in which they performed 46.6% of interventions, whereas surgeons and cardiologists combined performed the other 53.4%. In 2017, radiologists performed 7.56 services per 100,000 beneficiaries, which was 56.8% of the total count, more than those performed by surgeons, cardiologists, and unspecified providers combined.

CONCLUSIONS

Catheter-directed therapy is increasingly being used for the treatment of DVT, with its use undergoing a nearly 12-fold increase from 2007 to 2017 in the Medicare population. Radiologists remained the dominant provider of these services throughout the majority of study period, with a relative reduction in market share from 72% in 2007 to 57% in 2017.

Changing National Medicare Utilization of Catheter, Computed Tomography, and Magnetic Resonance Extremity Angiography: A Specialty-focused 16-Year Analysis

To assess changing utilization of extremity angiography from 2001 to 2016, focusing on modalities and provider specialties. Medicare PSPS Master Files from 2001-2016 and POSPUF from 2016 were used to determine overall and specialty utilization of diagnostic catheter angiography (DCA), CT angiography (CTA), and MR angiography (MRA). From 2001 to 2016, extremity angiography increased from 1107 to 1590 extremities imaged per 100,000 beneficiaries, with rapid expansion of CTA (22 in 2001 to 619 in 2009; plateau of 645 in 2016), but declines in DCA (1039 to 914) and MRA (45 to 30). Over time, extremity angiography shifted from 94% DCA, 4% MRA, and 2% CTA to 58% DCA, 41% CTA, and 2% MRA. For radiologists, extremity angiography increased slightly (741 to 767) with increases in CTA (20 to 595) and large decreases in DCA (681 to 145), with MRA remaining low (40 to 27). Extremity angiography increased for cardiologists (197 to 349) and vascular surgeons (87 to 351), both overwhelmingly performing DCA. Radiologists' share of all extremity angiography shifted from 67% to 48%, with interventionalists (47%), generalists (43%), and abdominal radiologists (7.4%) providing most radiologist services in 2016. Throughout, radiologists were the dominant providers of CTA (89% to 92%) and MRA (89% to 90%). Extremity angiography utilization in Medicare beneficiaries increased nearly 50% from 2001 to 2016, largely related to CTA performed by radiologists. Of radiologists, interventionalists and generalists together render most services. Cardiologists and surgeons assumed a large share of DCA previously performed by radiologists.

Transcatheter Dialysis Conduit Procedures: Changing National and State-Level Medicare Use Patterns over 15 Years

PURPOSE

To evaluate the changing use of transcatheter hemodialysis conduit procedures.

METHODS

Multiple Centers for Medicare & Medicaid Services datasets were used to assess hemodialysis conduit angiography. Use was normalized per 100,000 beneficiaries and stratified by specialty and site of service.

RESULTS

From 2001 to 2015, hemodialysis angiography use increased from 385 to 1,045 per 100,000 beneficiaries (compound annual growth rate [CAGR], +7.4%)]. Thrombectomy use increased from 114 to 168 (CAGR, +2.8%). Angiography and thrombectomy changed, by specialty, +1.5% and -1.3% for radiologists, +18.4% and +14.4% for surgeons, and +24.0% and +17.7% for nephrologists, respectively. By site, angiography and thrombectomy changed +29.1% and +20.7% for office settings and +0.8% and -2.4% for hospital settings, respectively. Radiologists' angiography and thrombectomy market shares decreased from 81.5% to 37.0% and from 84.2% to 47.3%, respectively. Angiography use showed the greatest growth for nephrologists in the office (from 5 to 265) and the greatest decline for radiologists in the hospital (299 to 205). Across states in 2015, there was marked variation in the use of angiography (0 [Wyoming] to 1173 [Georgia]) and thrombectomy (0 [6 states] to 275 [Rhode Island]). Radiologists' angiography and thrombectomy market shares decreased in 48 and 31 states, respectively, in some instances dramatically (eg, angiography in Nevada from 100.0% to 6.7%).

CONCLUSIONS

Dialysis conduit angiography use has grown substantially, more so than thrombectomy. This growth has been accompanied by a drastic market shift from radiologists in hospitals to nephrologists and surgeons in offices. Despite wide geographic variability nationally, radiologist market share has declined in most states.

Characteristics of MR Neuroimaging Services Billed by Radiologists versus Nonradiologists

BACKGROUND AND PURPOSE

Although most neuroimaging examinations are interpreted by radiologists, many nonradiologists provide interpretation services. We studied day of the week, site of service, and patient complexity differences for common Medicare MR neuroimaging examinations interpreted by radiologists versus nonradiologists.

MATERIALS AND METHODS

Using carrier claims files for a 5% sample of Medicare beneficiaries from 2012 to 2014, we identified all claims for brain and lumbar spine MR imaging examinations. Services were categorized by physician specialty, day of the week, and the site of service. Patient complexity was calculated using Charlson Comorbidity Indices. The χ² was performed to test statistical significance.

RESULTS

A provider specialty could be identified for 568,423 brain and lumbar spine MR imaging examinations. Of weekday examinations, radiologists interpreted 475,288 (92.3%), and nonradiologists, 39,510 (7.7%). Of weekend examinations, radiologists interpreted 52,028 (97.0%) and nonradiologists 1597 (3.0%). Radiologists interpreted 145,904 (98.7%) examinations in the inpatient hospital and emergency department settings versus 1882 (1.3%) by nonradiologists. Of all examinations, 44,547 of those interpreted by radiologists (8.4%) were on the most clinically complex patients versus 2139 (5.2%) for nonradiologists. All interspecialty differences for day of the week, the site of service, and patient complexity were statistically significant (P < .001).

CONCLUSIONS

Although radiologists interpret most common MR neuroimaging examinations for Medicare beneficiaries, in contrast to nonradiologists, they disproportionately render those services on weekends, in higher acuity sites, and on more complex patients. To optimize access and minimize disparities in necessary neuroimaging, quality metrics should consider such service characteristics.

Portosystemic Shunts: Stable Utilization and Improved Outcomes, Two Decades After the Transjugular Intrahepatic Portosystemic Shunt

PURPOSE

The aim of this study was to assess national trends in utilization, demographics, hospital characteristics, and outcomes of patients undergoing surgical or percutaneous portal decompression since the introduction of transjugular intrahepatic portosystemic shunts (TIPS).

METHODS

A retrospective analysis of patients undergoing surgical portal decompression and TIPS procedures was conducted using Medicare Physician/Supplier Procedure Summary Master Files from January 2003 through December 2013 and National (Nationwide) Inpatient Sample data from 1993, 2003, and 2012. Utilization rates normalized to the annual number of Medicare enrollees, estimated means, and 95% confidence intervals were calculated.

RESULTS

The Medicare total annual utilization rate per million for all portosystemic decompression procedures decreased by 6.5% during the study period, from 15.3 in 2003 to 14.3 in 2013. TIPS utilization increased by 19.4% (from 10.3 to 12.3 per million), whereas open surgical shunt utilization decreased by 60.0% (from 5.0 to 2.0 per million). TIPS procedures represented 86% of all procedures in 2013. From 1993 to 2012, mean age increased slightly (from 53.0 to 55.5 years, P < .05). The percentage of procedures performed at teaching hospitals increased, whereas in-hospital mortality and length of stay decreased by 42% (P < .05) and 20% (P < .05), respectively. Of factors evaluated, the performance of procedures on an elective basis was the most influential on in-hospital mortality (P < .01, all years studied) and length of stay (P < .0001, all years studied).

CONCLUSIONS

Approximately two decades after the introduction of TIPS, the utilization of all portal decompression procedures has remained relatively stable. The TIPS procedure represents the dominant portal decompression technique. In-hospital mortality and mean length of stay after decompression have decreased, partially because of the performance of procedures during elective admissions.

Central venous access: evolving roles of radiology and other specialties nationally over two decades

PURPOSE

The aim of this study was to evaluate national trends in central venous access (CVA) procedures over 2 decades with regard to changing specialty group roles and places of service.

METHODS

Aggregated claims data for temporary central venous catheter and long-term CVA device (CVAD) procedures were extracted from Medicare Physician/Supplier Procedure Summary Master Files from 1992 through 2011. Central venous catheter and CVAD procedure volumes by specialty group and place of service were studied.

RESULTS

Between 1992 and 2011, temporary and long-term CVA placement procedures increased from 638,703 to 808,071 (+27%) and from 76,444 to 316,042 (+313%), respectively. For temporary central venous catheters, radiology (from 0.4% in 1992 to 32.6% in 2011) now exceeds anesthesiology (from 37% to 22%) and surgery (from 30.4% to 11.7%) as the dominant provider group. Surgery continues to dominate in placement and explantation of long-term CVADs (from 80.7% to 50.4% and from 81.6% to 47.7%, respectively), but radiology's share has grown enormously (from 0.7% to 37.6% and from 0.2% to 28.6%). Although volumes remain small (<10% of all procedures), midlevel practitioners have experienced >100-fold growth for most services. The inpatient hospital remains the dominant site for temporary CVA procedures (90.0% in 1992 and 81.2% in 2011), but the placement of long-term CVADs has shifted from the inpatient (from 68.9% to 45.2%) to hospital outpatient (from 26.9% to 44.3%) setting. In all hospital settings combined, radiologists place approximately half of all tunneled catheters and three-quarters all peripherally inserted central catheters.

CONCLUSIONS

Over the past 2 decades, CVA procedures on Medicare beneficiaries have increased considerably. Radiology is now the dominant overall provider.

Systemic barriers to optimal hemodialysis access

Arteriovenous fistulas (AVFs) are considered the gold standard for hemodialysis vascular access based on their superior patency, low complication rates, improved adequacy, lower costs to the health care system, and decreased risk of patient mortality. The goals of the Fistula First Breakthrough Initiative are to achieve a prevalent AVF use rate of at least 66% nationally, to decrease central venous catheter use, and to reduce overall vascular access complication rates among patients on hemodialysis. Achieving optimal vascular access is a complex process and, unlike other dialysis outcomes, requires patient involvement as well as collaboration among nephrologists, surgeons, interventionalists, dialysis facilities, primary care physicians, and hospital systems. In 2009, the Fistula First Breakthrough Initiative assembled a team from varied backgrounds and perspectives to discover the systemic root causes as to why the AVF use rate in the United States is significantly lower than that in other industrialized countries. Ultimately, the 139 latent root causes identified by the root cause analysis team fall into the categories of patient, physician, and system. This article summarizes the current controversies in regard to improving AVF placement and reducing central venous catheter use, related to each of these three categories.