Risk Factors for Thirty-Day Readmissions After Lower Extremity Amputation in Patients With Vascular Disease.

Author information

1: Department of Surgery, Division of Vascular Surgery, University of Missouri Hospital & Clinics, One Hospital Drive, Columbia, MO 65212(∗). Electronic address: vogeltr@health.missouri.edu.
2: Department of Family and Community Medicine, University of Missouri, School of Medicine, Columbia, MO(†).
3: Department of Family and Community Medicine, University of Missouri, School of Medicine, Columbia, MO(‡).

Abstract

BACKGROUND:

Understanding risk factors associated with readmission after lower extremity amputation may indicate targets for reducing readmission.

OBJECTIVE:

To evaluate factors associated with all-cause 30-day readmission after lower extremity amputation procedures.

DESIGN:

Retrospective cohort study.

SETTING:

Inpatient.

PATIENTS:

A total of 2480 patients who had lower extremity amputations between 2008 and 2014 were selected from national electronic medical record database, Cerner Health Facts.

METHODS:

Univariate analysis of demographics, diagnoses, postoperative medications, and laboratory results were examined. Multivariate logistic regression models were used to identify characteristics independently associated with readmission overall and by amputation location-above the knee (AKA) or below the knee (BKA).

MAIN OUTCOME MEASUREMENT:

Readmission within 30 days of discharge.

RESULTS:

More than one half of patients (1403, 57%) underwent BKA and 1077 (43%) underwent AKA. Readmission within 30 days was 22% (24.1% BKA versus 19.4% AKA, P = .005). In multivariable logistic regression, factors associated with 30-day readmission after any amputation included BKA (odds ratio [OR] 1.41, 95% confidence interval [CI] 1.15-1.74, P = .001), hypertension (OR 1.70, 95% CI 1.33-2.16), surgical-site infections (OR 1.44, 95% CI 1.02-2.04), heart failure (OR 1.39, 95% CI 1.10-1.75), discharge to a skilled nursing facility (OR 1.88, 95% CI 1.41-2.51), and emergency/urgent procedures (OR 1.32, 95% CI 1.04-1.67). At readmission, 13.3% of patients with a BKA required an AKA revision, and 21.3% had a diagnosis of surgical-site infection.

CONCLUSIONS:

Risk factors for readmission after any amputation included cardiac comorbidities, associated postoperative medications, and discharge to a skilled nursing facility. The finding that acute arterial embolism or thrombosis and a BKA during the index admission was highly associated with readmission, combined with the high rates of 30-day conversion to an AKA when readmitted, suggests these patients more often develop stump complications or may be undertreated during the initial hospitalization.