What Is the Quality of Surgical Care for Patients with Hip Fractures at Critical Access Hospitals?
Authors: Malik Azeem Tariq , Bonsu Janice M. , Roser Megan , Khan Safdar N. , Phieffer Laura S. , Ly Thuan V. , Harrison Ryan K. , Quatman Carmen E. 
Published: August 2020

Abstract

Background
Critical access hospitals (CAHs) play an important role in providing access to care for many patients in rural communities. Prior studies have shown that these facilities are able to provide timely and quality care for patients who undergo various elective and emergency general surgical procedures. However, little is known about the quality and reimbursement of surgical care for patients undergoing surgery for hip fractures at CAHs compared with non-CAH facilities.

Questions/purposes
Are there any differences in 90-day complications, readmissions, mortality, and Medicare payments between patients undergoing surgery for hip fractures at CAHs and those undergoing surgery at non-CAHs?

Methods
The 2005 to 2014 Medicare 100% Standard Analytical Files were queried using ICD-9 procedure codes to identify Medicare-eligible beneficiaries undergoing open reduction and internal fixation (79.15, 79.35, and 78.55), hemiarthroplasty (81.52), and THA (81.51) for isolated closed hip fractures. This database was selected because the claims capture inpatient diagnoses, procedures, charged amounts and paid claims, as well as hospital-level information of the care, of Medicare patients across the nation. Patients with concurrent fixation of an upper extremity, lower extremity, and/or polytrauma were excluded from the study to ensure an isolated cohort of hip fractures was captured. The study cohort was divided into two groups based on where the surgery took place: CAHs and non-CAHs. A 1:1 propensity score match, adjusting for baseline demographics (age, gender, Census Bureau-designated region, and Elixhauser comorbidity index), clinical characteristics (fixation type and time to surgery), and hospital characteristics (whether the hospital was located in a rural ZIP code, the average annual procedure volume of the operating facility, hospital bed size, hospital ownership and teaching status), was used to control for the presence of baseline differences in patients presenting at CAHs and those presenting at non-CAHs. A total of 1,467,482 patients with hip fractures were included, 29,058 of whom underwent surgery in a CAH. After propensity score matching, each cohort (CAH and non-CAH) contained 29,058 patients. Multivariate logistic regression analyses were used to assess for differences in 90-day complications, readmissions, and mortality between the two matched cohorts. As funding policies of CAHs are regulated by Medicare, an evaluation of costs-of-care (by using Medicare payments as a proxy) was conducted. Generalized linear regression modeling was used to assess the 90-day Medicare payments among patients undergoing surgery in a CAH, while controlling for differences in baseline demographics and clinical characteristics.

Results
Patients undergoing surgery for hip fractures were less likely to experience many serious complications at a critical access hospital (CAH) than at a non-CAH. In particular, after controlling for patient demographics, hospital-level factors and procedural characteristics, patients treated at a CAH were less likely to experience: myocardial infarction (3% (916 of 29,058) versus 4% (1126 of 29,058); OR 0.80 [95% CI 0.74 to 0.88]; p < 0.001), sepsis (3% (765 of 29,058) versus 4% (1084 of 29,058); OR 0.69 [95% CI 0.63 to 0.78]; p < 0.001), acute renal failure (6% (1605 of 29,058) versus 8% (2353 of 29,058); OR 0.65 [95% CI 0.61 to 0.69]; p < 0.001), and Clostridium difficile infections (1% (367 of 29,058) versus 2% (473 of 29,058); OR 0.77 [95% CI 0.67 to 0.88]; p < 0.001) than undergoing surgery in a non-CAH. CAHs also had lower rates of all-cause 90-day readmissions (18% (5133 of 29,058) versus 20% (5931 of 29,058); OR 0.83 [95% CI 0.79 to 0.86]; p < 0.001) and 90-day mortality (4% (1273 of 29,058) versus 5% (1437 of 29,058); OR 0.88 [95% CI 0.82 to 0.95]; p = 0.001) than non-CAHs. Further, CAHs also had risk-adjusted lower 90-day Medicare payments than non-CAHs (USD 800, standard error 89; p < 0.001).

Conclusion
Patients who received hip fracture surgical care at CAHs had a lower risk of major medical and surgical complications than those who had surgery at non-CAHs, even though Medicare reimbursements were lower as well. Although there may be some degree of patient selection at CAHs, these facilities appear to provide high-value care to rural communities. These findings provide evidence for policymakers evaluating the impact of the CAH program and allocating funding resources, as well as for community members seeking emergent care at local CAH facilities.

Level of Evidence
Level III, therapeutic study.