A Critical Look At Readmissions For Patients With Diabetic Foot Infections

As the incidence of diabetes climbs to over 9 percent among the United States population, the occurrence of diabetic foot infection (DFI) has also reached historic proportions.^1,2While physicians are making substantial efforts to prevent hospitalizations for the treatment of diabetes-related foot disease, inpatient care for DFIs remains at an all-time high.³ 

Inpatient care is often complex and taxing, and typically requires substantial resources to prove it is effective. At the terminus of medical, surgical and infection control interventions, the ideal formulation of treatment, discharge, follow-up and patient education is becoming increasingly important in the consideration of success. Patient readmission is entering a new spotlight as the heightened scrutiny of unplanned patient rehospitalization “within 30 days of discharge from an acute care hospital” takes administrative center stage.^4,5

The Centers for Medicare and Medicaid Services (CMS) monitors readmissions for causes that fall under many categories with the expectation of continued expansion of categorical monitoring. Under this oversight, medical facilities that experience categorical rehospitalization rates higher than the CMS threshold will experience reduction of or, in certain circumstances, non-payment of claims.⁶This recent shift in focus to readmission comes in the wake of the Affordable Care Act’s section 3025 mandate of the implementation of a Hospital Readmissions Reduction Program (HRRP) beginning in 2013.⁷The HRRP intends to “give hospitals strong financial incentive” with the threat of reduced payment for patient care services. The CMS maintains an assumption that this will “make Americans’ health care better” and that readmission rates are inverse to a patient’s “quality of care.”⁷

Presently, there is a paucity of literature exploring or verifying readmission rates for patients with diabetic foot infections. According to the current research, readmission rates for DFI after surgical debridement can range between 17 to 23 percent.^8,9

The Healthcare Cost and Utilization Project reported on readmissions to U.S. hospitals by “procedure.”⁸Among the 30 most common procedures reported, “lower extremity amputation” was the procedure with the highest readmission rate, surpassing 25 percent among Medicare patients greater than 65 years of age. In this same report, readmission rates among Medicare patients greater than 65 years of age surpassed 24 percent after lower extremity debridement alone, which ranked 11th among the 30 reported reasons for readmission. Additionally, when categorizing by “diagnosis,” Weiss and coworkers found gangrene to be the second highest readmission diagnosis at a readmission rate of 31.6 percent. Patients with diagnoses of “chronic ulceration” and “diabetes mellitus with complications” reportedly average readmission rates of 21.3 and 20.3 percent respectively.

It should be of little wonder that the treatment of DFI in the American health care system is of significant financial importance.^10,11These factors in combination with the continually increasing cost of hospitalization and tightening restrictions on payment culminate into an alarming forecast for the care of those with DFIs.¹²

Why Readmission Can Be So Complex

In considering the reasons for readmission, physicians who are familiar with diabetic limb salvage may readily recognize that the factors that prompt a patient to return to the hospital after discharge are endless, ranging from simple (often not qualifying for readmission) to complex with a serious threat of morbidity or mortality. Additionally, although patients return to the hospital systems of their prior admission, many patients will receive evaluation by different physicians than those involved in previous episodes of care, which can cause a division in the continuum of care.

Here we offer a few brief, very simplified scenarios we have experienced at our training hospitals that present a few of the complexities of readmission.

The VAC change. A patient returns to the hospital emergency department for a negative pressure wound therapy (NPWT) dressing change four days after discharge. A miscommunication with his home health care nurse led to the patient missing the first dressing change. The patient was readmitted for the treatment of cellulitis and wound care prior to evaluation by the podiatry team. At this time, the treating podiatrists noted a complex wound.

The ambulatory nurse evaluation. A patient returns on the recommendation of her home health care provider for “worsening wound appearance.” The patient was readmitted for the management of gangrene and cellulitis. The physical evaluation by the podiatrist revealed large areas of dry, yellow-brown fibrous tissue with superficial detritus overlying pink, well-perfused granular tissue. Physicians performed bedside debridement and initiated collagenase therapy.

What did we miss?A young patient with Charcot foot deformity was directly admitted to the hospital by his podiatrist for the treatment of cellulitis and evaluation of osteomyelitis. The patient had been discharged three weeks prior after wound debridement, biopsy, deep tissue culture and infectious disease consultation. He related the extremity had a worsening appearance and pain. The patient was receiving IV antibotic infusions and also confirmed that he was still maintaining non-weightbearing status. Upon readmission, the patient was diagnosed with osteomyelitis and had surgical and antibiotic intervention.

Guess who is back?A 65-year-old non-ambulatory man presents with uncontrolled type 2 diabetes, end-stage renal disease on hemodialysis, diabetic retinopathy and multiple bilateral lower extremity amputations. Two weeks after wound debridement and IV antibiotics, he returns to the hospital emergency department of his own volition stating his “foot is infected.” He is very familiar patient with the limb salvage service. He did not contact the physician who was following him as an outpatient. Subsequent workup in the emergency department revealed no clinical evidence of infection. The patient was readmitted for further workup, partially due to his persistence, and was discharged a few days later without significant intervention.

Misguided groupthink. A patient with multiple severe comorbidities presented to the emergency department for evaluation of worsening wound appearance and persistent right extremity pain. Two weeks prior, he had evaluation by the limb salvage team including podiatry, vascular surgery and infectious disease specialists for a chronic, non-healing wound with cellulitis. He had surgical debridement and culture-guided IV antibiotic therapy with good immediate results, and was discharged. On physical evaluation, the wound appeared healthy but was without notable improvement, and pulses were diminished to the affected limb. Upon the patient’s readmission, advanced vascular imaging demonstrated near total occlusion of the common femoral artery of the affected leg, which surgeons subsequently addressed operatively.

Key Insights On Mitigating Readmission Risk

These few simplified scenarios are within the realm of those that we see at our institutions with some regularity. Each scenario is complex and driven by a combination of medical and human factors, which in sum can be difficult to manipulate into a consistently pleasing outcome. Furthermore, the current medical environment, being organized and assessed by coded input into electronic medical records systems, limits comprehensive evaluation of the many factors of patient readmission, resulting in potentially misleading and poorly representative metrics.

Given the potential consequences of the Hospital Readmissions Reduction Program on hospital systems and the near epidemic levels of DFIs, one should consider ways to reduce risks to the patient and the health care system overall.

Inpatient classification systems.Upon the initial evaluation during a patient hospitalization, the utilization of a validated classification system (such as the Society for Vascular Surgery Wound, Ischemia and Foot Infection (WIFi) system) in relaying and stratifying clinical findings can relay clinical correlation with prognosis and initial hospitalization length of stay to those involved in patient care.^13–15Additionally, because the WIFi classification also aids in the assessment of healing potential, a higher (worse) score on this system may be an early indicator to the care team as to the risk of future rehospitalization.^9,16The utilization of the WIFi classification system, in particular, promotes repetitive and reproducible evaluations of critical parameters of a DFI (extent of the wound, perfusion, extent of infection) by new and experienced practitioners alike, theoretically reducing some of the risk involved with inadequate physical examination, effectively reducing the risk of patient return for further workup or treatment.

Clear and concise communications. Patients with longstanding diabetes demonstrate increased susceptibility to early cognitive decline, impaired verbal understanding and multiple forms of diminished mentation relative to their non-diabetic counterparts.^17–20Upon discharge, providing basic yet helpful information, including a written warning as to the signs and symptoms of infection, readily visible contact information, plain instructions for dressing changes and defining the next office visit and emergency bandage instructions are simple ways to decrease the loss of information between discharge and an outpatient evaluation. Whenever possible, the discussion of patient care with family members alongside patients has demonstrated improved patient adherence and outcome.²¹Finally, it may be necessary to lower one’s threshold for ordering home health care on discharge in an effort to promote adherence and reduce readmission.

The checks and balances of a team approach. Modern inpatient care of the DFI requires the collaboration of a comprehensive diabetic foot team including, at a minimum, podiatrists, vascular surgeons and infectious disease specialists. This combined approach allows specialists to independently evaluate and participate in the treatment of the critical parameters of patient care. The redundancy in physical examination inherent in a team approach reduces oversight and improves outcomes in the care of the DFI, which may correlate with decreased readmission.^22–25
 
In Conclusion

There are many instances in which patient readmission is unavoidable and necessary. Ideally, this would fall within any future regulations from the Hospital Readmissions Reduction Program. However, efforts toward reducing unplanned admission redundancy could improve the metrics of patient care that CMS has identified as indicators of quality as well as afford the foot and ankle specialist additional time and energy to focus on a smaller inpatient census. Although future research needs to explore the rate and cause of readmission among patients with diabetic foot disease, a preemptive approach may reduce the risk of penalty in the face of ever restrictive Medicare reimbursements. Furthermore, in the increasingly metric-driven medical atmosphere, reduction of unplanned readmission could reduce system expenditures and organizational financial risk all the while improving patient satisfaction.²⁶ 

Dr. King is a second-year resident at Tucson Medical Center in Tucson, Ariz.

Dr. Hatch is in private practice at Saguaro Surgical in Tucson, Ariz.

References
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2.      Van Netten JJ, Price PE, Lavery LA, et al. Prevention of foot ulcers in the at-risk patient with diabetes: a systematic review. Diabetes Metab Res Rev. 2016;32(Suppl 1):84–98.
3.      Hobizal KB, Wukich DK. Diabetic foot infections: current concept review. Diabet Foot Ankle. 2012;3.
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5.     Horwitz L, Partovian C, Lin Z, et al. Hospital-wide (all-condition) 30-day risk-standardized readmission measure. Ann Intern Med.2014; 161(10 Suppl):S66–75.
6.     Centers for Medicare and Medicaid Services. Readmissions reduction program. Available at https://www.cms.gov/medicare/medicare-fee-for-service-payment/acuteinpatientpps/readmissions-reduction-program.html .
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12.     Hospital Adjusted Expenses per Inpatient Day by Ownership. Available at https://www.kff.org/health-costs/state-indicator/expenses-per-inpatient-day-by-ownership/ . Published Feb. 2, 2017.
13.     Mills Sr. JL, Conte MS, Armstrong DG, et al. The Society for Vascular Surgery Lower Extremity Threatened Limb Classification System: Risk stratification based on Wound, Ischemia, and foot Infection (WIfI). J Vasc Surg. 2014;59(1):220–234.e2.
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16.     Mathioudakis N, Hicks CW, Canner JK, et al. The Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) classification system predicts wound healing but not major amputation in patients with diabetic foot ulcers treated in a multidisciplinary setting. J Vasc Surg. 2017;65(6):1698–1705.e1.
17.     Bangen KJ, Gu Y, Gross AL, et al. Relationship between type 2 diabetes mellitus and cognitive change in a multiethnic elderly cohort. J Am Geriatr Soc.2015;63(6):1075–1083.
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19.     Vanhanen M, Koivisto K, Kuusisto J, et al. Cognitive function in an elderly population with persistent impaired glucose tolerance. Diabetes Care. 1998;21(3):398–402.
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21.     Martire LM, Schulz R. Involving family in psychosocial interventions for chronic illness. Curr Dir Psychol Sci. 2007;16(2):90–94.
22.     Sumpio BE, Armstrong DG, Lavery LA, Andros G. The role of interdisciplinary team approach in the management of the diabetic foot: a joint statement from the Society for Vascular Surgery and the American Podiatric Medical Association. J Vasc Surg. 2010;51(6):1504–1506.
23.     Tseng C-L, Rajan M, Miller DR, Lafrance J-P, Pogach L. Trends in Initial Lower Extremity Amputation Rates Among Veterans Health Administration Heath Care System Users From 2000 to 2004. Diabetes Care.2011; 34(5):1157–63.
24.     Larsson J, Apelqvist J, Agardh CD, Stenström A. Decreasing incidence of major amputation in diabetic patients: a consequence of a multidisciplinary foot care team approach? Diabet Med. 1995;12(9):770–776.
25.     Krishnan S, Nash F, Baker N, Fowler D, Rayman G. Reduction in diabetic amputations over 11 years in a defined UK population: benefits of multidisciplinary team work and continuous prospective audit. Diabetes Care. 2008;31(1):99–101.
26.     Jencks SF, Williams MV, Coleman EA. Rehospitalizations among patients in the Medicare fee-for-service program. N Engl J Med. 2009;360(14):1418–1428.

Additional Reference
27.     Fincke BG, Miller DR, Turpin R. A classification of diabetic foot infections using ICD-9-CM codes: application to a large computerized medical database. BMC Health Serv Res. 2010;10: 192.