Hospital Readmissions in Vascular Surgery

Introduction

Healthcare spending in the United States has increased dramatically over the past several decades. As of 2020, the US spends approximately $3.6 trillion annually on healthcare, or over 17% of the nation’s gross domestic product (GDP) ( Fig. 37.1 ). This is projected to reach over $6 trillion (almost 20% of GDP) annually by 2028. This unsustainable spending has driven a keen interest in cost containment and the concept of increasing value in healthcare.

While value in healthcare is somewhat easy to define as healthcare outcomes per dollar spent, actually measuring both dollars spent and healthcare outcomes can be quite challenging. Given this, proxies are often used in an attempt to capture outcomes or indicators of quality of care. One such measure that has received a great deal of attention is unplanned readmissions.

Readmission is a common occurrence that results in increased costs to both patients and to the healthcare system as a whole. It has been estimated that potentially preventable readmissions cost Medicare approximately $12 billion annually. Under the assumption that at least a fraction of these readmissions are related to breakdown in care and poor transition from the inpatient to the outpatient setting, readmissions have become a marker of quality of a hospital and reducing readmissions has become a focus of healthcare reform and the Affordable Care Act (ACA). This focus on readmissions, specifically 30-day readmissions, as well as the financial penalties that are now tagged to this metric, have driven physicians, hospitals, and healthcare organizations to devote substantial time and effort to minimizing readmission. While on its face avoiding expensive hospitalizations would seem to benefit the system as a whole, emphasizing 30-day readmission as a primary quality metric, and tagging to it what can be steep financial penalties for hospitals, obscures what could be a holistic view to patient care and moves focus from clinical outcomes to what many have deemed a somewhat arbitrary measure.

Particularly for surgeons, how to best quantify and report quality has been a challenge. As stated by Lord Kelvin, the 19th century mathematical physicist who calculated the point of absolute zero on the thermodynamic temperature scale, “…when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind.” For surgical specialties that treat patients with significant comorbidities, readmissions may be driven by factors outside of the surgeon’s control.

Hospital Readmissions Reduction Program

The Centers for Medicare and Medicaid Services (CMS) uses a diagnosis-related group (DRG) payment scheme for hospital reimbursement. DRGs were introduced by CMS in 1983 as an alternative to the initial payment model for CMS, which had no incentive to control cost. The DRG system has been revised multiple times since then, and in its current incarnation attempts to capture patient illness severity, comorbidities, risk of mortality, interventions, and likely resource use. Payments are calculated by multiplying the fees by the DRG code plus modifiers for hospital factors including teaching institutions, low-volume hospitals, transfers, and outliers. While unlike direct billing, DRGs attempt to control costs by limiting payments to adjusted but set amounts, they continue to incentivize hospitals to operate at or near capacity in order to bill for patients treated. In addition to the many changes that came with the ACA, a focus of cost control was also implemented and one aspect of that was a focus on 30-day readmissions under the Hospital Readmissions Reduction Program (HRRP). To capture this, CMS calculated anticipated readmission rates based on performance over the prior 3 years and then instituted penalties for institutions that were above that calculated benchmark. The readmission period is defined as 30 days from discharge rather than from procedure date, an important nuance particularly in surgical specialties, and captures readmission to any part of the hospital, to either surgical or nonsurgical specialties. In 2012, readmission measures began with acute myocardial infarction (AMI), heart failure (HF), and pneumonia ( Fig. 37.2 ). Also pertinent to surgeons, in 2014 CMS began to adjust for planned readmissions. Beginning in 2015, chronic obstructive pulmonary disease (COPD) became a tracked condition as well as elective total hip arthroplasty (THA) and total knee arthroplasty (TKA). Coronary artery bypass graft (CABG) was included as of 2017. Once expected risk-adjusted readmissions are calculated, the excess readmission ratio (ERR) is calculated and reimbursement for each targeted DRG is then discounted by that ratio to a maximum penalty of 3% of the hospital’s annual DRG payments. The total Medicare penalties assessed in 2017 were $528 million USD with the average penalty less than 1% of Medicare payments for that institution. Only 1.8% of hospitals faced the maximum 3% penalty.