Risk Factors for 30-Day Hospital Re-Admission with an Infectious Complication after Lower-Extremity Vascular Procedures

Toward Uniform Case Identification Criteria in Observational Studies on Peripheral Arterial Disease: A Scoping Review

BACKGROUND

The diagnosis of peripheral arterial disease (PAD) is commonly applied for symptoms related to atherosclerotic obstructions in the lower extremity, though its clinical manifestations range from an abnormal ankle-brachial index to critical limb ischemia. Subsequently, management and prognosis of PAD vary widely with the disease stage. A critical aspect is how this variation is addressed in administrative database-based studies that rely on diagnosis codes for case identification. The objective of this scoping review is to inventory the identification strategies used in studies on PAD that rely on administrative databases, to map the pros and cons of the International Classification of Diseases (ICD) codes applied, and to propose a first outline for a consensus framework for case identification in administrative databases.

METHODS

Registry-based reports published between 2010 and 2021 were identified through a systematic PubMed search. Studies were subcategorized on the basis of the expressed study focus: claudication, critical limb ischemia, or general peripheral arterial disease, and the ICD code(s) applied for case identification mapped.

RESULTS

Ninety studies were identified, of which 36 (40%) did not specify the grade of PAD studied. Forty-nine (54%) articles specified PAD grade studied. Five (6%) articles specified different PAD subgroups in methods and baseline demographics, but not in further analyses. Mapping of the ICD codes applied for case identification for studies that specified the PAD grade studied indicated a remarkable heterogeneity, overlap, and inconsistency.

CONCLUSIONS

A large proportion of registry-based studies on PAD fail to define the study focus. In addition, inconsistent strategies are used for PAD case identification in studies that report a focus. These findings challenge study validity and interfere with inter-study comparison. This scoping review provides a first initiative for a consensus framework for standardized case selection in administrative studies on PAD. It is anticipated that more uniform coding will improve study validity and facilitate inter-study comparisons.

Discharge process challenges of an academic vascular surgery service: A qualitative study

Vascular surgery patients have a high incidence of unplanned hospital readmissions and complications. Previous research has not fully examined specific elements of the hospital discharge process for vascular surgery patients to identify issues that may contribute to readmissions. The objective of this qualitative descriptive study was to explore challenges identified by healthcare providers and patients regarding the discharge process from an academic vascular surgery service. Data were collected from eight focus group interviews and analyzed for relevant themes. Patients and healthcare providers identified several challenges within the standard discharge process, including ineffective communication, insufficient time for discharge education, and limitations accessing providers with post-discharge concerns. These obstacles may be ameliorated in part by specialized coordinators, caregiver support, and use of adaptive strategies outside of the current discharge process. The discharge challenges described by study participants likely contribute to adverse post-hospitalization outcomes, including unplanned hospital readmissions. A multifaceted approach that incorporates standardized discharge processes, as well as informal problem-solving strategies, is recommended to improve hospital discharge and outcomes for vascular surgery patients.

Interventions to Prevent Readmissions in Hospitalized Peripheral Vascular Surgery Patients: A Systematic Review

A large proportion of peripheral vascular patients worldwide experience unplanned hospital readmissions after inpatient vascular surgery. This review was conducted to identify acute care and post-discharge interventions that may help in reducing unplanned vascular surgery readmissions. A computer-based search of four databases was conducted July 2021 for original research reports published 2000 to 2021. Eight studies met inclusion criteria, with interventions including multidisciplinary care teams, advance practice provider discharge coordination, individualized case management, home care nursing, early primary care provider or telephone follow-up, and telehealth driven follow up evaluated. Some reductions in readmission rates were associated with most interventions but were inconsistent across studies. Further research is necessary to clarify and validate these findings, incorporate patient perspectives, and explore the role of technology-based interventions. This work is key to improving the patient's experience, reduce healthcare costs, and strengthen the quality of vascular surgery care.

Peripheral Artery Disease and Subsequent Risk of Infectious Disease in Older Individuals: The ARIC Study

OBJECTIVE

To quantify the association of peripheral artery disease (PAD) with infection risk because PAD has been understudied despite recognition of atherosclerotic cardiovascular disease as a risk factor for infection.

METHODS

Among 5082 participants of the Atherosclerosis Risk in Communities study (aged 71 to 90 years during 2011-2013), we assessed the association of PAD status, based on clinical history and ankle-brachial index (ABI), with infection-related hospitalization (through December 2019) using multivariable Cox regression. We also cross-classified participants by PAD and coronary heart disease (CHD)/stroke status at baseline, with implications for polyvascular disease.

RESULTS

During the median follow-up of 6.5 years, there were 1677 infection-related hospitalizations. Peripheral artery disease (clinical history or ABI ≤0.90) was independently associated with the risk of overall infection (adjusted hazard ratio [HR], 1.66 [95% CI, 1.42 to 1.94] vs ABI of 1.11 to 1.20), as was borderline low ABI of 0.91 to 1.00 (adjusted HR, 1.75 [95% CI, 1.47 to 2.07]). Results were consistent across major types of infection (ie, cellulitis, bloodstream infection, pneumonia, and urinary tract infection). For overall infection, PAD plus CHD/stroke had the highest HR of hospitalized infection (1.9), and PAD alone and CHD/stroke alone showed similar HRs of 1.6. For subtypes of infection, PAD alone had the highest HR of approximately 2 for bloodstream infection; PAD alone and PAD plus CHD/stroke had a similar risk of urinary tract infection with HR of approximately 1.7.

CONCLUSION

Peripheral artery disease and borderline low ABI were robustly associated with infection-related hospitalization of older adults. The contribution of PAD to infection risk was comparable to that of CHD/stroke, warranting clinical attention to PAD for the prevention of infectious diseases.

Preoperative HbA1c and Outcomes Following Lower Extremity Vascular Procedures

OBJECTIVES

Limited data exist evaluating pre-operative hemoglobin A1c (HbA1c) in patients undergoing vascular procedures for peripheral arterial disease (PAD). This study evaluated the relationship of preoperative HbA1c on outcomes after open and endovascular lower extremity (LE) vascular procedures for PAD.

METHODS

We selected patients with PAD admitted for elective LE procedures between September 2008 and December 2015 from the Cerner Health Facts® database using ICD-9-CM diagnosis and procedure codes. Bivariable analysis and multivariable logistic models examined the association of patient characteristics, procedure type, and preoperative HbA1c (normal < 6.5%, high ≥ 6.5%) with postsurgical outcomes that included infection, renal failure, respiratory or cardiac complications, length of stay (LOS), in-hospital mortality, and readmission.

RESULTS

Of 4,087 patients who underwent a LE vascular procedure for PAD, 2,462 (60.2%) had a preoperative HbA1c recorded. The cohort was mostly male (60%), white (73%), and underwent endovascular intervention (77%). Patients with high HbA1c levels were more likely of black race (p < .02) and had significantly higher comorbidities (p < .0001). Elevated HbA1c was associated with diabetes (p < .0001) and cellulitis (p = .05) on unadjusted analysis. Multivariable logistic regression (adjusting for patient, hospital, comorbidity and procedural characteristics) revealed that elevated HbA1c was significantly associated with 30-day readmission (OR = 1.06, 95% CI = 1.00-1.12), but was not associated with the other outcomes. An independent diagnosis of diabetes was not predictive of complications or readmission.

CONCLUSIONS

Historic glucose control, as evidenced by a high preoperative HbA1c level, is not associated with adverse outcome, other than readmission, in patients undergoing LE procedures for PAD. Given the known association of high perioperative glucose levels with poor outcome following vascular procedures, this is suggestive of a more important effect of perioperative, as opposed to chronic, glucose control upon outcome. Thus, we suggest focusing efforts on creating standardized goal-directed guidelines for glucose control in the perioperative period for LE vascular procedures to potentially mitigate complications.

Incidence and causes of early unplanned readmission after hospitalisation with peripheral arterial disease in Australia and New Zealand

OBJECTIVE

To evaluate the characteristics and predictors of unplanned readmission within 30 days of hospitalisation for the treatment of peripheral arterial disease (PAD) in Australia and New Zealand.

DESIGN

Analysis of hospitalisations data in the Admitted Patient Collection for each Australian state and territory and the New Zealand National Minimum Dataset (Hospital Events).

SETTING

All public and 80% of private hospitals in Australia and New Zealand.

PARTICIPANTS

Adults (18 years or older) hospitalised with a primary or conditional secondary diagnosis of PAD during 1 January 2010 - 31 December 2015.

MAIN OUTCOME MEASURE

Rate of unplanned readmission (any cause) within 30 days of hospitalisation with PAD.

RESULTS

Of 104 979 admissions included in our analysis (mean patient age, 73.7 years; SD, 12.4 years), 9765 were followed by at least one unplanned readmission within 30 days of discharge (9.3%): 3395 within one week (34.8%) and 7828 within three weeks (80.2%). The most frequent readmission primary diagnoses were atherosclerosis (1477, 15.3%), type 2 diabetes (1057, 10.8%), and "complications of procedures not elsewhere classified" (963, 9.9%). Readmission was more frequent after acute (4830 of 26 304, 18.4%) than elective PAD hospitalisations (4935 of 78 675, 6.3%), but the readmission characteristics were similar. Factors associated with greater likelihood of readmission included acute PAD hospitalisations (odds ratio [OR], 2.04; 95% CI, 1.96-2.17), surgical intervention during the PAD hospitalisation (OR, 1.74; 95% CI, 1.64-1.84), and chronic limb-threatening ischaemia (OR, 1.55; 95% CI, 1.47-1.63).

CONCLUSION

Unplanned readmissions within 30 days of hospitalisation for PAD are often for potentially preventable reasons. Their number should be reduced to improve clinical outcomes for people with PAD.

Groin wound infection after vascular exposure (GIVE) multicentre cohort study

Surgical site infections (SSIs) of groin wounds are a common and potentially preventable cause of morbidity, mortality, and healthcare costs in vascular surgery. Our aim was to define the contemporaneous rate of groin SSIs, determine clinical sequelae, and identify risk factors for SSI. An international multicentre prospective observational cohort study of consecutive patients undergoing groin incision for femoral vessel access in vascular surgery was undertaken over 3 months, follow-up was 90 days. The primary outcome was the incidence of groin wound SSI. 1337 groin incisions (1039 patients) from 37 centres were included. 115 groin incisions (8.6%) developed SSI, of which 62 (4.6%) were superficial. Patients who developed an SSI had a significantly longer length of hospital stay (6 versus 5 days, P = .005), a significantly higher rate of post-operative acute kidney injury (19.6% versus 11.7%, P = .018), with no significant difference in 90-day mortality. Female sex, Body mass index≥30 kg/m2 , ischaemic heart disease, aqueous betadine skin preparation, bypass/patch use (vein, xenograft, or prosthetic), and increased operative time were independent predictors of SSI. Groin infections, which are clinically apparent to the treating vascular unit, are frequent and their development carries significant clinical sequelae. Risk factors include modifiable and non-modifiable variables.

A prospective investigation of depression and adverse outcomes in patients undergoing vascular surgical interventions: A retrospective cohort study using a large mental health database in South London

BACKGROUND

Patients with depression are more susceptible to cardiovascular illness including vascular surgeries. However, health outcomes after vascular surgery among patients with depression is unknown. This study aimed to investigate associations of depression with post-operative health outcomes for vascular surgical patients.

METHODS

A retrospective observational study was conducted using data from a large mental healthcare provider and linked national hospitalization data for the same south London geographic catchment. OPCS-4 codes were used to identify vascular procedures. Health outcomes were compared between those with/without depression including length of hospital stay (LOS), inpatient mortality, and 30 day emergency hospital readmissions. Predictors of these health outcomes were also assessed.

RESULTS

Vascular surgery was received by 9,267 patients, including 446 diagnosed with depression. Patients with depression had a higher risk of emergency admission for vascular surgery (odds ratio [OR] 1.28; 1.03, 1.59), longer index LOS (IRR 1.38; 1.33-1.42), and a higher risk of 30-day emergency readmission (OR 1.82; 1.35-2.47). Patients with depression had higher inpatient mortality after adjustment for sociodemographic status (1.51; 1.03, 2.23) but not on full adjustment, and had longer emergency readmission LOS (1.13; 1.04, 1.22) after adjustment for sociodemographic factors and cardiovascular disease. Correlates of vascular surgery hospitalization among patients with depression included admission through emergency route for longer LOS, inpatient mortality, and 30-day hospital readmission.

CONCLUSION

Patients with depression undergoing vascular surgery have substantially poorer health outcomes. Screening for depression prior to surgery might be indicated to target preventative measures.

An Infected Popliteal Aneurysm after Plain Old Balloon Angioplasty

The case was a 76-year-old man with chronic limb-threatening ischemia. Plain old balloon angioplasty (POBA) was performed on the popliteal artery. Subsequently, he suffered from cellulitis around the POBA site, followed by reocclusion. Staphylococcus aureus was detected in a blood culture. After re-revascularization with POBA, both purulent gonitis and an infected popliteal aneurysm were observed to occur. We performed aneurysmectomy and bypass grafting with the saphenous vein and then continued antibiotic therapy. Although treatment consisted of endovascular therapy (EVT) with nothing left behind, management was difficult because of secondary infectious complications. We conclude that prophylactic antibiotics before EVT should be considered in such cases.

Complex relationship between low albumin level and poor outcome after lower extremity procedures for peripheral artery disease

OBJECTIVE

A low albumin level has been associated with poor outcome, including death, in surgical patients. The mechanistic relationship, however, is more complex than simply nutritional. As studies are scant in the vascular population, we sought to examine the association of low albumin level with outcomes in patients undergoing open and endovascular lower extremity procedures for peripheral artery disease.

METHODS

Patients with peripheral artery disease undergoing lower extremity procedures (2008-2015) were selected from Cerner Health Facts database (Cerner Corporation, Kansas City, Mo) using International Classification of Diseases, Ninth Revision diagnosis and procedure codes. Age, sex, disease severity, and other comorbidities were captured. Outcomes were identified using codes and encounter data. A χ²analysis and multivariable logistic regression were performed.

RESULTS

There were 6170 patients evaluated; 4562 (74%) underwent endovascular procedures and 1608 (26%) underwent open surgery. Low albumin level (<3.5 g/dL) was associated with age ≥80 years (23.1% vs 16.3% normal; P < .0001), black race (21% vs 11.6% normal; P < .0001), tissue loss (38% vs 16.4% normal; P < .0001), and higher Charlson index (mean, 3.1 vs 2.2 in the normal group; P < .0001). Low albumin level was also associated with longer length of stay (4.9 vs 2.2 days normal; P < .0001), higher in-hospital mortality (1.9% vs 0.3% normal; P < .0001), and higher 30-day readmission (15% vs 12.7% normal; P = .02). Multivariable analysis demonstrated that low albumin level was strongly associated with in-hospital death (odds ratio [OR], 5.23; 95% confidence interval [CI], 2.00-13.70), infection (OR, 2.51; 95% CI, 1.96-3.22), renal failure (OR, 2.61; 95% CI, 1.79-3.79), and cardiac complications (OR, 2.59; 95% CI, 1.69-3.96). After multivariable adjustment, there was no association between albumin level and 30-day readmission.

CONCLUSIONS

Low preoperative albumin levels are associated with in-hospital death, prolonged length of stay, and severe morbidity after open and endovascular lower extremity procedures. As the majority of lower extremity procedures are elective, serious consideration should be given to deferring elective procedures until albumin levels have been optimized. Because of the pleiotropic effects of albumin, including antiplatelet and inflammatory function, study of this complex relationship may offer insights into how best to integrate this novel biomarker into vascular surgery decision-making.

Proposed Classification of Incision Complications: Analysis of a Prospective Study on Elective Open Lower-Limb Revascularization

Background: Incision complications (IC) have a significant impact on procedure-related morbidity after lower-limb revascularization. One of the most studied IC is surgical site infection (SSI). Reporting these complications in a uniform way is crucial to evaluate treatment approaches. The aim of this study was to propose a comprehensive classification of IC and apply it to compare SSI with other IC in a trial on elective open lower-limb revascularization procedures. Methods: Two hundred twenty-three eligible patients undergoing elective unilateral inguinal and infra-inguinal arterial vascular surgery were extracted from a randomized controlled trial on incisional negative-pressure wound therapy (NPWT) on inguinal vascular surgical incisions. The IC were classified by grades of severity (grade 0-6) that focused on IC-related consequences such as out-patient treatment (grade 1), prolonged in-patient treatment (grade 2), re-admission (grade 3), and re-operation (grade ≥4). An SSI was defined by the ASEPSIS score criteria. Results: An SSI was diagnosed in 63 patients (28.3%). Thirty-five of 160 patients (21.8%) not suffering from SSI underwent IC treatment. Treatment for IC was recorded for 25/144 patients (17.4%) with satisfactory site healing as judged by the ASEPSIS score. The median incision-related in-hospital stay in those with SSI (n = 79) and disturbed healing (n = 16) according to the ASEPSIS score was 13 days in both groups (p = 0.53). Five patients had peri-vascular SSI (IC grade 4 n = 4; grade 5 n = 1). The proposed classification of IC and the ASEPSIS score correlated highly (r = 0.77; p < 0.001). Inter-rater reliability for IC grading was substantial for three investigators with different levels of experience (k = 0.81, 0.71, and 0.70). Conclusions: The proposed incision classification suggests a comparable clinical significance of vascular IC in terms of IC-related in-patient stay, whether there was a surgical site infection or not. This classification system requires external validation.

Are 30-Day Outcomes Enough? Late Infectious Readmissions following Prosthetic-Based Breast Reconstruction

BACKGROUND

Surgical-site infection is a major concern in prosthetic-based breast reconstruction. Thirty-day postoperative readmission rates are a common quality metric, but little is known about readmission rates for later infections.

METHODS

Using the 2013 to 2014 Nationwide Readmissions Database, the authors identified breast cancer patients undergoing breast reconstruction with implants and tissue expanders who had an infectious readmission. The authors used univariate and multivariate logistic regression models to identify predictors of infectious readmission and explantation within the early (0 to 30 days) and late (31 to 90 days) postoperative periods.

RESULTS

In the weighted sample, the authors identified 18,338 patients undergoing prosthetic-based breast reconstruction. The overall infectious readmission rate was 4.1 percent (n = 759): 49.3 percent occurred early and 50.7 percent occurred late. Of the infectious readmissions, 39.5 percent required explantation, 55.1 percent of which occurred during a late infectious readmission. Seventy-five percent of these infectious readmissions and explantations occurred within 49 days of initial surgery. Median annual household income less than $40,000 (p = 0.035), diabetes (p = 0.038), and obesity (p = 0.004) were independent predictors of infectious readmission. Diabetes (p = 0.049) and hypertension (p = 0.011) were independent predictors of early readmission. Median annual household income less than $40,000 (p = 0.049), obesity (p = 0.006), and increasing length of stay during the index procedure (p = 0.028) were independent predictors of late readmission. No statistically significant independent predictors for explantation were identified.

CONCLUSIONS

Traditional 30-day readmission rates are not an adequate quality metric for breast reconstruction given the number of late postoperative readmissions, many of which lead to explantation. Early and late infectious readmissions have different predictors. Interventions targeting these predictors may decrease the number of readmissions, thus reducing cost and improving quality.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Risk factors of major infections in schizophrenia. A nationwide Danish register study

BACKGROUND

Risk of infections is elevated in patients with schizophrenia. Predicting their occurrence is essential, as infections in this group of patients are associated with prolonged hospital admission and increased mortality. The objective of the current investigation was to identify the potential risk factors of major infection after diagnosis with schizophrenia.

METHODS

This national prospective observational cohort study included 7788 people with schizophrenia born in Denmark between 1975 and 1990. Socio-demographic, psychiatric and health related data were obtained from Danish national registers. The Cox regression model was used for data analyses. Crude and adjusted hazard ratios (HRs) with 95% confidence intervals (95%CIs) are presented.

RESULTS

The most significant risk factors associated with the development of major infections included young age, female gender, medical comorbidity and substance abuse. A history of treatment with antipsychotics preceding the diagnosis was negatively associated with such morbidity.

CONCLUSION

This study reports several factors that might increase the risk of infections in individuals with schizophrenia. Early intervention towards infections should be considered in the subpopulation of schizophrenia patients who are at increased risk of infections.

Readmissions to an alternate hospital in patients undergoing vascular intervention for claudication and critical limb ischemia associated with significantly higher mortality

BACKGROUND

Hospital readmissions with 30 days after vascular surgical interventions have been associated with increased morbidity, mortality, and cost. Readmission rates, now a Centers for Medicare and Medicaid Services quality measure, have been studied in databases that have excluded certain payer types and states and have not accounted for readmission to a hospital different from that of the index admission. More accurate and nationally representative data are needed, because this fragmentation of care could lead to flawed conclusions. The purpose of the present study was to examine the incidence and risk factors for readmission to a nonindex hospital for patients admitted for claudication or critical limb ischemia (CLI). We also examined how this disruption of patient care affects mortality.

METHODS

The 2013 to 2014 Nationwide Readmissions Database was queried for all patients admitted for claudication or CLI who had undergone angioplasty, lower extremity bypass, or aortobifemoral bypass. The outcomes of interest were 30- and 365-day readmission rates to any hospital, 30- and 365-day readmission rates to a nonindex hospital, and mortality rates. Multivariable logistic regression was used to identify risk factors for readmission to a nonindex hospital. The most common readmission diagnoses and diagnosis-related groups were identified.

RESULTS

A total of 92,769 patients had been admitted with peripheral vascular disease (33,055 with claudication and 59,714 with CLI). The 30- and 365-day readmission rate was 8.97% and 21.49% and 19.26% and 40.36%, for claudication and CLI, respectively. Of the 30- and 365-day readmissions, 20.47% and 24.92% had occurred at a nonindex hospital, respectively. Significantly higher mortality rates were found for patients with 30- or 365-day readmissions to different hospitals (odds ratio, 1.4 and 1.8, respectively). Multivariable analysis revealed that procedural indication and angioplasty are not significant risk factors for readmission to a different hospital. However, female sex, length of stay >7 days, and Charlson Comorbidity Index >3 remained significant risk factors for nonindex readmissions. The most common disease groups for nonindex readmission were "septicemia and disseminated infections" (6.5%), "heart failure" (6.4%), "other vascular procedures" (6.1%), and "amputation of lower limb except toes" (4.0%).

CONCLUSIONS

Previously unreported, ≥1 in 4 readmissions after lower extremity vascular procedures for peripheral vascular disease will occur at a nonindex hospital. This fragmentation of care is associated with increased mortality and has serious implications for guiding outcome and quality measures. With a sizeable portion of patients missed by current metrics, concern exists that providers are using flawed data. Further study into social- and patient-specific risk factors might provide methods to prevent these readmissions and improve outcomes in this difficult patient population.

Comparative Study of the Effects of Customized 3D printed insole and Prefabricated Insole on Plantar Pressure and Comfort in Patients with Symptomatic Flatfoot

BACKGROUND There are many shortcomings in traditional prefabricated rehabilitation insoles for symptomatic flatfoot patients. This study investigated the effects of customized 3-dimensional (3D) printed insoles on pressure and comfort of the plantar foot in symptomatic flatfoot patients. MATERIAL AND METHODS Eighty patients with bilateral flatfoot participated in this study. At week 0, patients were randomly assigned into 1 of 2 groups. In the control group, the patients wore standardize shoes with prefabricated insoles; and in the experimental group the patients wore standardize shoes and customized insoles. The Footscan® system recorded peak pressure, peak force, and peak contact area in 10 areas of the sole at weeks 0 and at week 8. Patients used visual analogue scale scores at week 0 and at week 8 to assess overall comfort of insoles. RESULTS At week 0, compared with the control group, the peak pressure in the metatarsal was significantly lower in the experimental group (P<0.05) while the peak pressure in the mid-foot was significantly higher than the control group (P<0.05). At week 8, in the experimental group, the peak pressures in the mid-foot were significantly higher than the control group (P<0.05). The comfort scores (measured by pain scale) reported by the experimental group were significantly lower than those reported by the control group (P<0.05). CONCLUSIONS Customized 3D printed insoles reduced the pressure on the metatarsals by distributed it over the mid-foot area, thus reduced the damage from symptomatic flatfoot. Customized 3D printed insoles were more effective than prefabricated insoles and offered better comfort for patients with symptomatic flatfoot.

Cohort study of risk factors for 30-day readmission after abdominal aortic aneurysm repair

Background: We conducted a retrospective cohort study of thirty-day readmission after abdominal aortic aneurysm (AAA) repair. Patients and methods: Inpatients (2009-2016) undergoing elective AAA repair were selected from the multicenter Cerner Health Facts® database using ICD-9 procedure codes. We identified characteristics associated with 30-day readmission with chi-square analysis and logistic regression. Results: 4,723 patients undergoing elective AAA procedures were identified; 3,101 endovascular aneurysm repairs (EVAR) and 1,622 open procedures. Readmission differed by procedure type (6.5 % EVAR vs. 9.3 % open, p =.0005). Multivariable logistic regression found that patients undergoing EVAR were less likely to be readmitted (OR 0.71, 95 % CI 0.54-0.92) than patients undergoing open repair. The following risk factors were associated with 30-day readmission following any AAA repair: surgical site infection during the index admission (OR 2.79, 95 % CI 1.25-6.22), age (OR 1.03, 95 % CI 1.01-1.05), receipt of bronchodilators (OR 1.34, 95 % CI 1.06-1.70) or steroids (OR 1.45, 95 % CI 1.04-2.02), serum potassium > 5.2 mEq/L (OR 1.89, 95 % CI 1.16-3.06), and higher Charlson co-morbidity scores (OR 1.12, 95 % CI 1.04-1.21). Subgroup analysis revealed that age (OR 1.02, 95 % CI 1.01-1.04), higher Charlson comorbidity scores (OR 1.20, 95 % CI 1.09-1.33), and receipt of post-operative bronchodilators (OR 1.39, 95 % CI 1.03-1.88) were risk factors for 30-day readmission following EVAR. After open procedures, readmission was associated with surgical site infection during the index admission (OR 2.91, 95 % CI 1.17-7.28), chronic heart failure (OR 2.18, 95 % CI 1.22-3.89), and receipt of post-operative steroids (OR 1.92, 95 % CI 1.24-2.96). The most common infections were pneumonia after open procedures and urinary tract infection after EVAR. Conclusions: The risk factor most associated with 30-day readmission after elective AAA repair was surgical site infection. Awareness of these risk factors and vulnerable groups may help identify high-risk patients who could benefit from increased surveillance programs to reduce readmission.

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

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.

LEVEL OF EVIDENCE

III.

Impact of Patient Safety Indicators on readmission after abdominal aortic surgery

Patient safety is a critical component of health-care quality and measures created by the Agency for Healthcare Research and Quality (AHRQ) to identify hospitalizations with potentially preventable adverse events. This analysis evaluated whether Patient Safety Indicator (PSI) events after open surgical repair (OSR) or endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm (AAA) were associated with increased risk of readmission. Patients undergoing elective repair of nonruptured AAA from 2009 to 2012 were selected in the Medicare Provider Analysis and Review files using the International Classification of Diseases, Ninth Revision, Clinical Modification codes. To identify PSI events, we used the AHRQ PSI International Classification of Diseases, Ninth Revision, Clinical Modification numerator codes. Chi-square test, multivariable logistic regression analysis, nonparametric Wilcoxon rank sum test, and Kaplan-Meier survival analysis were used for statistics. A total of 66,923 patients undergoing elective AAA repair were evaluated: (1) 9,315 with OSR and (2) 57,608 with EVAR. The most frequent PSI events after OSR versus EVAR were postoperative respiratory failure (PSI, 11; 17.7% vs 1.8%; P < .0001); perioperative hemorrhage/hematoma (PSI, 9; 3.6% vs 2.6%; P < .0001); postoperative sepsis (PSI, 13; 3.5% vs 0.4%; P < .0001); accidental puncture or laceration (PSI, 15; 2.1% vs 0.6%; P < .0001); and postoperative acute kidney injury requiring dialysis (PSI, 10; 1.4% vs 0.2%; P < .0001). The overall 30-day readmission rate was 10.5%. The occurrence of any PSI event overall significantly increased 30-day readmission compared with no event cases (odds ratio [OR] = 1.71; 95% confidence interval [CI], 1.57-1.86). Likelihood of 30-day readmission was greater for postoperative acute kidney injury requiring dialysis (OR = 1.66; 95% CI, 1.28-2.15), postoperative respiratory failure (OR = 1.36; 95% CI, 1.22-1.52), perioperative hemorrhage (OR = 1.34; 95% CI, 1.18-1.52), and postoperative pressure ulcer (OR = 2.88; 95% CI, 1.99-4.17). Occurrence of any PSI event was associated with an increased total hospital and intensive care unit length of stay and total hospital charges (all P < .001). In conclusion, AHRQ PSI events may be used to identify patients at the greatest risk for readmission after AAA repair. The risk for 30-day readmission was 71% higher when a PSI event occurred and was not associated with the type of repair. Minimizing preventable PSI events may be beneficial to reducing hospital readmissions after open and endovascular AAA repair and to improving hospital resource utilization.