Analysis of Early Lower Extremity Re-amputation.

BACKGROUND: Data is scarce regarding the need for early re-amputation to a higher anatomic level. This study seeks to define outcomes and risk factors for re-amputation. METHODS: Patients undergoing primary major lower extremity amputation were identified within the 2012-2016 ACS-NSQIP database. Demographics, outcomes, and peri-operative characteristics were compared, and multivariable logistic regression model was used to determine association with early re-amputation. RESULTS: Over a 4-year period, 8306 below knee amputations and 6367 above knee amputations were identified. Thirty-day re-amputation occurred in 262 patients (1.8%) and was associated with increased length of stay (12.9 vs. 7.3 days, P < 0.001), higher rates of readmission (64.9% vs. 13.6%, P < 0.001), and overall complications (69.5% vs. 39.3%, P < 0.01). On multivariable analysis, advanced age (OR 1.02, CI 1.01-1.03), smoking (OR 1.75, CI 1.32-2.33), dialysis dependence (OR 1.67, CI 1.23-2.26), preoperative septic shock (OR 2.53, CI 1.29-4.97), and bleeding disorders (OR 1.72, CI 1.34-2.22) were associated with early re-amputation. CONCLUSIONS: Thirty-day re-amputation rates are low, but are associated with significant morbidity, prolonged hospitalization, and frequent readmissions.

Present-day analysis of early failure after forefoot amputation.

BACKGROUND: Forefoot transmetatarsal amputation is performed commonly to achieve limb salvage, but transmetatarsal amputations have a high rate of failure, requiring more proximal amputations. Few contemporary studies have examined the incidence of major amputation (transtibial or transfemoral) after transmetatarsal amputation. The goal of this study is to determine risk factors and outcomes for a more proximal amputation after forefoot amputation. METHODS: We queried the 2012 to 2016 database of the American College of Surgeons National Quality Improvement Program for patients undergoing a complete transmetatarsal amputation with wound closure by Current Procedural Terminology code. Patients requiring early (within 30 days) more proximal amputation after transmetatarsal amputation were compared with those who did not need further amputation. Characteristics of patients requiring more proximal amputation were examined, and a multivariable logistic regression model was created to identity risk factors for early more proximal amputation. RESULTS: In the study, 1,582 transmetatarsal amputation were identified. Most patients were male (70%), white (59%), and diabetic (74%), with a median age of 63 years. More proximal amputation occurred in 4.2% of patients within the first 30 days postoperatively. This early failure was associated with greater hospital stays postoperatively (10 days vs 7 days), more wound complications (29% vs 11%), pneumonia (8% vs 2%), stroke (3% vs 0.1%), and overall complications (50% vs 28%; P ≤ .025 each). Although there was no difference in 30-day mortality (P = .27), there was a marked increase in unplanned readmission (59% vs 14%; P < .0001) for those undergoing reamputation. On multivariable analysis, preoperative systemic inflammatory response, sepsis, or septic shock (odds ratio 2.1; 95% confidence interval, 1.2-3.6) were independent predictors of more proximal amputation. CONCLUSION: Early below-knee or above-knee amputation early after transmetatarsal amputation leads to increased morbidity. Because patients with preoperative sepsis may be at increased risk of failure after transmetatarsal amputation, the level of amputation should be considered carefully in these patients.

Diabetes and Its Effect on Abdominal Aortic Aneurysm Growth Rate in Hispanic Patients.

BACKGROUND: The growth rate of abdominal aortic aneurysms (AAA) can vary depending on age, baseline diameter, blood pressure, race, and history of smoking. Paradoxically, previous studies show evidence of a protective effect of diabetes on the rate of AAA expansion despite its well-established role in the morbidity and mortality of cardiovascular disease. This study aims to investigate the impact diabetes plays on AAA growth within a Hispanic population. METHODS: Data were collected from patients who were predominantly Mexican-American at a single hospital site. Baseline and follow-up measures for AAA diameter were obtained from serial imaging studies. Demographics, medical history, the presence of type 2 diabetes, and medication use were extracted from hospital records. Linear mixed-effects growth models were used to calculate the overall AAA growth rate and to assess the difference in AAA growth rate between demographics, comorbidities, and medication use. RESULTS: The study comprised 201 patients (70.4% male) with a mean baseline age of 79.1 years, of whom 43.2% were diabetic. The average monthly AAA growth rate across all study participants was 0.15 mm (SE = 0.02 mm). Independently, the average AAA expansion rate for the diabetic and nondiabetic groups was 0.07 mm (SE = 0.04 mm) and 0.21 mm (SE = 0.03 mm) per month, respectively. This demonstrates a 65% lower linear AAA expansion rate per month in patients with diabetes. CONCLUSIONS: This study confirms a difference of AAA physiology between diabetics and nondiabetics in the Hispanic community. The observed significant difference in AAA growth rate may be a combination of factors associated with race/ethnicity, prevalence of diabetes mellitus, and low compliance with diabetic control exhibited in the Mexican-American population.

The effect of Hispanic ethnicity on surgical outcomes: An analysis of the NSQIP database.

BACKGROUND: Existing literature has shown racial/ethnic disparities between white and black surgical populations, however, surgical outcomes for Hispanic patients are limited in both scope and quantity. METHODS: Data from the American College of Surgeons National Surgical Quality Improvement Program from 2007 to 2015 was used to analyze surgical outcomes in approximately 3.5 million patients. RESULTS: Overall, Hispanics experienced lower odds of mortality compared to non-Hispanic White, non-Hispanic Black, and non-Hispanic American Indian or Alaska Native patients (all P < 0.0001). No difference was found in mortality odds between Hispanics and non-Hispanic Asian or Native Hawaiian patients. Hispanics experienced minimal disparities in complications as compared to non-Hispanic White and non-Hispanic Black but had a higher rate of select complications when compared to Non-Hispanic Asian, Native Hawaiian, or Pacific Islander. CONCLUSION: Hispanics, in general, had lower odds of 30-day postoperative mortality and major morbidity compared to most of the races/ethnicities included in the ACS NSQIP database.

Thirty-day outcomes after fenestrated endovascular repair are superior to open repair of abdominal aortic aneurysms involving visceral vessels.

OBJECTIVE: Although few studies have reported outcomes after branched or fenestrated endovascular aortic aneurysm repair (FEVAR) of abdominal aortic aneurysms involving visceral vessels (AAA-Vs), no multi-institutional study has compared FEVAR with open surgery (OS) for AAA-Vs. Our objective was to compare 30-day outcomes after FEVAR vs OS for AAA-Vs. METHODS: Patients who underwent FEVAR (n = 535) and OS (n = 1207) for elective AAA-Vs were identified from the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) 2008 to 2013 database. Thoracoabdominal aneurysms were excluded. Univariable and multivariable logistic regression analyses were performed. RESULTS: There were more men (82% vs 72%; P < .0001), diabetic patients (16% vs 11%; P = .005), patients with dependent functional status (4% vs 2%; P = .002), and nonsmokers (70% vs 56%; P < .0001) in the FEVAR group vs OS. There was no difference in rates of chronic obstructive pulmonary disease, cardiac history, peripheral artery disease, hypertension, and dialysis (P > .05). FEVAR had fewer major postoperative pulmonary complications (3.0% vs 19.0%; P < .0001), less renal failure requiring dialysis (1.9% vs 6.4%; P < .0001), less frequent cardiac arrest or myocardial infarction (2.2% vs 5.8%; P = .001), less bleeding with major transfusion (17.4% vs 50.2%; P < .0001), and decreased incidence of return to the operating room (4.5% vs 9.6%; P < .0001) and death (2.4% vs 4.7%; P = .02). The median length of stay was also significantly shorter for FEVAR (2 days vs 7 days; P < .0001). On multivariable analyses, OS was associated with higher risk than FEVAR for 30-day death (odds ratio [OR], 2.6; 95% confidence interval [CI], 1.3-5.0), pulmonary complications (OR, 8.8; 95% CI, 5.1-15.0), cardiac complications (OR, 3.4; 95% CI, 1.8-6.6), renal failure needing dialysis (OR, 3.8; 95% CI, 1.9-7.7), and return to the operating room (OR 2.5; 95% CI, 1.6-4.0). CONCLUSIONS: FEVAR is associated with a lower risk for 30-day mortality and adverse events compared with OS for AAA-Vs.

Outcomes After Use of Aortouniiliac Endoprosthesis Versus Modular or Unibody Bifurcated Endoprostheses for Endovascular Repair of Ruptured Abdominal Aortic Aneurysms.

OBJECTIVES: Outcomes after endovascular repair (EVAR) of ruptured abdominal aortic aneurysms (rAAAs) have been widely published. There is, however, controversy on the role of the use of aortouniiliac endoprosthesis (AUI) versus modular or unibody bifurcated endoprosthesis (MUB) for repair of rAAAs. We study and compare 30-day outcomes after use of AUI and MUB for all rAAAs focusing specifically on patients with instability. MATERIALS AND METHODS: Patients who underwent EVAR for rAAA (n = 425) using AUI (n = 55; 12.9%) and MUB (n = 370; 87.1%) were identified from the American College of Surgeons' National Surgical Quality Improvement Program (2005-2010) database. Univariable and multivariable logistic regression analyses were performed. RESULTS: No significant difference ( P > .5) was seen in comorbidities between patients who underwent EVAR with AUI or MUB; there was also no change in endoprosthesis use from 2005 to 2010 ( P = .7). Patients who underwent EVAR with AUI more commonly had a history of peripheral arterial procedure (10.9% vs 4.6%; P = .053) and preoperative transfusion of >4 U packed red blood cells (18.2% vs 6.8%; P = .004). Use of AUI versus MUB was associated with more 30-day wound complications (16.4% vs 6.2%; P = .01), return to operating room (38.2% vs 20.0%; P = .003), and mortality (34.5% vs 21.4%; P = .03). On multivariable analysis, use of AUI was associated with an increased risk of 30-day mortality (odds ratio: 2.4; 95% confidence interval: 1.1-5.3). On subanalysis of the cohort for only the patients with unstable rAAA (n = 159; AUI = 29 and MUB = 130), 30-day mortality for AUI versus MUB was still higher but not statistically significant (44.8% vs 32.3%; P = .2). CONCLUSION: Endovascular repair for ruptured AAA using aortouniliac endoprosthesis is associated with higher 30-day mortality than using modular or unibody bifurcated endoprosthesis.

Outcomes of Aortic Surgery for Abdominal Aortic Graft Infections.

BACKGROUND: Literature on postoperative outcomes following aortic surgery for aortic graft infection (AGI) is limited by relatively small sample sizes, resulting in lack of national benchmarks for quality of care. We report in-hospital outcomes following abdominal aortic surgery for AGI and identify factors associated with postoperative complications using the Nationwide Inpatient Sample (NIS) database. METHODS: Patients who underwent aortic graft resection for AGI were identified from the 2002 to 2008 NIS database, a multicenter database capturing 20% of all US admissions. Multivariable logistic regression analyses were performed. RESULTS: Among 394 patients (men: 73.4%) who underwent abdominal aortic surgery for AGI, 53% of the admissions were emergent/urgent. A significant trend for decreasing number of abdominal aortic surgery for AGIs per year was observed (Pearson r correlation: -.96; P = .0006). Over the same time span, a significant correlation was also seen with decrease in open and increase in endovascular aortic aneurysm repairs in the NIS database. In-hospital rates of overall postoperative morbidity and mortality were 68.3% and 19.8%, respectively. In-hospital rates of postoperative respiratory failure, renal failure, and cardiac arrest were 35.5%, 14.2%, and 8.9%, respectively. Median length of stay was 26 days, with median hospital charges being US$184 162. On multivariable analysis, increase in age per year (odds ratio [OR] 1.07; 95% confidence interval [CI]: 1.03-1.12) was independently associated with postoperative morbidity, while higher hospital volume for this procedure was protective (OR: 0.71; 95% CI: 0.56-0.89). No preoperative factors were independently associated with postoperative mortality. CONCLUSION: Incidence of abdominal aortic surgery for AGI has progressively declined over the span of our study in association with decreased open and increased endovascular aortic aneurysm repairs. Aortic surgery for AGI is associated with very high morbidity and mortality rates along with prolonged lengths of stay and elevated hospital charges. The outcomes of operations for AGI are better in younger patients and higher volume hospitals.

Morbidity and mortality after use of iliac conduits for endovascular aortic aneurysm repair.

OBJECTIVE: Although placement of an open iliac conduit for endovascular aortic aneurysm repair (EVAR) is generally felt to result in higher morbidity and mortality, published literature is scarce. Our objective was to assess 30-day outcomes after elective EVAR with an open iliac conduit using a multi-institutional database. METHODS: Patients who underwent elective EVAR (n = 14,339) for abdominal aortic aneurysm were identified from the American College of Surgeons National Surgical Quality Improvement Program 2005 to 2011 database. Univariable and multivariable logistic regression analyses were performed. RESULTS: An open iliac conduit was used in 231 patients (1.6%), and the remainder had femoral exposure or percutaneous EVAR. Women comprised 32% of patients with iliac conduits in contrast to 17% of those without iliac conduits. Patients with iliac conduits were older and had a lower body mass index. Univariable analysis showed patients with open iliac conduits had a higher incidence of postoperative pneumonia (3.0% vs 1.1%), ventilator dependence (4.8% vs 1.0%), renal failure (3.0% vs 0.7%), cardiac arrest or myocardial infarction (5.2% vs 1.1%), return to the operating room (9.1% vs 3.7%), major morbidity (16.0 vs 6.6%), and death (3.0% vs 0.9%). On multivariable analysis, the use of open iliac conduits was associated with higher risk of 30-day mortality (odds ratio, 2.7; 95% confidence interval, 1.2-6.0) and 30-day major morbidity (odds ratio, 2.3; 95% confidence interval, 1.6-3.3). CONCLUSIONS: Patients with open iliac conduits for EVAR are more likely to be female and have higher postoperative morbidity and mortality. For patients with complex iliac artery disease, conduits are a viable alternative after EVAR to be performed, albeit at an increased risk. These data do suggest the need for lower-profile grafts and other alternative strategies for navigating complex iliac artery disease.

Percutaneous thoracic endovascular aortic repair for ascending aortic pseudoaneurysm after prosthetic aortic valve repair.

Ascending aortic pseudoaneurysms are an uncommon and challenging surgical problem that requires intervention to avoid rupture and hemorrhage. Preceding cardiac procedures often compound the high rate of morbidity and mortality associated with open repair. A case is described of an iatrogenic pseudoaneurysm in a patient with a recently placed prosthetic aortic valve and a clinical course precluding repeat open operative procedure. An endovascular approach was used, with placement of a thoracic aorta endograft with temporary cardiac pacing and a double-curved Lunderquist wire to avoid instrumenting the prosthetic aortic valve. At 9 months of follow-up, the patient returned to his baseline activity status, and at 24 months, had no symptoms or signs of infection, and a computed tomography angiogram demonstrated pseudoaneurysm exclusion with no graft migration.

Preoperative frailty Risk Analysis Index to stratify patients undergoing carotid endarterectomy.

OBJECTIVE: Rapid and objective preoperative assessment of patients undergoing carotid endarterectomy (CEA) remains problematic. Preoperative variables correlate with increased morbidity and mortality, yet no easily implemented tool exists to stratify patients. We determined the relationship between our fully implemented frailty-based bedside Risk Analysis Index (RAI) and complications after CEA. METHODS: Patients undergoing CEA in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database from 2005 to 2011 were included. Variables of frailty RAI were matched to preoperative NSQIP variables, and outcomes including stroke, mortality, myocardial infarction (MI), and length of stay were analyzed. We further analyzed patients who were symptomatic and asymptomatic before CEA. RESULTS: With use of the NSQIP database, 44,832 patients undergoing CEA were analyzed (17,696 [39.5%] symptomatic; 27,136 [60.5%] asymptomatic). Increasing frailty RAI score correlated with increasing stroke, death, and MI (P < .0001) as well as with length of stay. RAI demonstrated increasing risk of stroke and death on the basis of risk stratification (low risk [0-10], 2.1%; high risk [>10], 5.0%). Among patients undergoing CEA, 88% scored low (<10) on the RAI. In symptomatic patients, the risk of stroke and death for patients with a score of ≤10 is 2.9%, whereas if the RAI score is 11 to 15, it is 5.0%; 16 to 20, 6.9%; and >21, 8.6%. In asymptomatic patients, the risk of stroke and death for patients with a score of ≤10 is 1.6%, whereas if the RAI score is 11 to 15, it is 2.9%; 16 to 20, 5.2%; and >21, 6.2%. CONCLUSIONS: Frailty is a predictor of increased stroke, mortality, MI, and length of stay after CEA. An easily implemented RAI holds the potential to identify a limited subset of patients who are at higher risk for postoperative complications and may not benefit from CEA.

A comparison of open surgery versus endovascular repair of unstable ruptured abdominal aortic aneurysms.

OBJECTIVE: Two randomized trials to date have compared open surgery (OS) and endovascular (EVAR) repair for ruptured abdominal aortic aneurysm (rAAA); however, neither addressed optimal management of unstable patients. Single-center reports have produced conflicting data regarding the superiority of one vs the other, with the lack of statistical power due to low patient numbers. Furthermore, previous studies have not delineated between the outcomes of stable patients with a contained rupture vs those patients with instability. Our objective was to compare 30-day outcomes in patients undergoing OS vs EVAR for all rAAAs, focusing specifically on patients with instability. METHODS: Patients who underwent repair of rAAA were identified from the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database (2005 to 2010). Unstable patients with rupture were identified as those who were American Society of Anesthesiologists Physical Status Classification 4 or 5 requiring emergency repair with at least one of the following: preoperative shock, preoperative transfusion of >4 units, preoperative intubation, or preoperative coma or impaired sensorium. Univariable and multivariable logistic regression analyses were performed. RESULTS: Of the 1447 patients with rAAA, 65.5% underwent OS and 34.5% EVAR. Forty-five percent were unstable, and for these patients, OS was performed in 71.3% and EVAR in 28.7%. The 30-day mortality rate was 47.9% (OS, 52.8%; EVAR, 35.6%; P < .0001) for unstable rAAAs and was 22.4% for stable rAAAs (OS, 26.3%; EVAR, 16.4%; P = .001). Amongst patients with unstable rAAA, 26% had a myocardial infarction or cardiac arrest ≤ 30 days (OS, 29.0%; EVAR, 19.1%; P = .006), and 17% needed postoperative dialysis (OS, 18.7%; EVAR, 12.8%; P = .04). Amongst patients with stable rAAA, 13.6% had a myocardial infarction or cardiac arrest ≤ 30 days (OS, 14.9%; EVAR, 11.6%; P = .20), and 11.5% needed postoperative dialysis (OS, 13.3%; EVAR, 8.7%; P = .047). Multivariable analyses showed OS was a predictor of 30-day mortality for unstable rAAA (odds ratio, 1.74; 95% confidence interval, 1.16-2.62) and stable rAAA (odds ratio, 1.64; 95% confidence interval, 1.10-2.43). CONCLUSIONS: Approximately one-third of patients treated for rAAA undergo EVAR in NSQIP participating hospitals. Not surprisingly, unstable patients have less favorable outcomes. In both stable and unstable rAAA patients, EVAR is associated with a diminished 30-day mortality and morbidity.

Unplanned readmissions after vascular surgery.

OBJECTIVE: Existing literature on readmission after vascular surgery is limited. The upcoming reduction in Medicare reimbursement for institutions with high readmission rates mandates an accurate understanding of this issue. In this study, we characterize the frequency and causes of 30-day unplanned readmissions after elective vascular surgery. METHODS: Patients who underwent elective carotid endarterectomy (CEA), endovascular aortic repair (EVAR), open abdominal aortic aneurysm (oAAA) repair, or infrainguinal bypass grafting (BPG) were identified from the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) 2011 database (n = 11,246). Multivariable logistic regression was used to determine variables that contributed to 30-day unplanned readmissions for each surgery type. RESULTS: The unadjusted unplanned readmission rates after the four vascular procedures ranged from 6.5% for CEA to 15.7% for BPG. In multivariable analyses, patient comorbidities were associated with unplanned readmission after BPG and CEA (P < .05), whereas postoperative complications were more consistently associated with unplanned readmission after EVAR and oAAA repair (P < .05). For all procedures, complications leading to readmission developed more frequently after discharge. Thirty-day mortality was significantly higher in readmitted patients after BPG (1.9% vs 0.3%), EVAR (3.9% vs 0.1%), and CEA (2.2% vs 0.2%; P < .001 for each), but not after oAAA repair. CONCLUSIONS: Select comorbidities and postoperative complications contribute to unplanned readmissions after vascular surgery. The characteristics of readmitted patients vary with the type of procedure. Interventions designed to mitigate these factors have the potential to reduce unplanned readmissions but likely need to vary with the type of vascular treatment.

Clinical characteristics associated with readmission among patients undergoing vascular surgery.

OBJECTIVE: Readmission after a vascular surgery intervention is frequent, costly, and often considered preventable. Vascular surgery outcomes have recently been scrutinized by Medicare because of the high rates of readmission. We determined patient and clinical characteristics associated with readmission in a cohort of vascular surgery patients. METHODS: From 2009 to 2013, the medical records of all patients (n = 2505) undergoing interventions by the vascular surgery service at a single tertiary care institution were retrospectively reviewed. Sociodemographic and clinical characteristics were examined for association with 30-day readmission to the same institution. RESULTS: The 30-day readmission rate to the same institution was 9.7 % (n = 244). Procedures most likely to result in readmission were below-knee (25%), foot (22%), and toe amputations (19%), as well as lower extremity revascularization (22%). Patients covered by Medicaid (16.8%) and Medicare (10.0%) were most likely to be readmitted, followed by fee-for-service (9.5%), self-pay (8.0%), and health maintenance organizations (5.5%; P < .05). Patients urgently admitted were more likely to be readmitted (16.2%) than those electively admitted (9.1%; P < .01). Patient severity as rated using the All Patient Refined Diagnosis Related Groups software (3M Health Information Systems, Wallingford, Conn) predicted readmission (16.2% high vs 6.2% low severity; P < .01). Initial length of stay was longer for readmitted than nonreadmitted patients (8.5 vs 6.1 days, respectively; P < .01). Intensive care unit admission during the initial hospitalization was associated with higher readmission rates in univariable analysis (18.3% with vs 9.5% without intensive care unit stay; P < .05). Discharge destination was also a strong predictor of readmission (rehabilitation, 19.2%; skilled nursing facility, 16.2%; home, 6.2%; P < .01). The effects of urgent admission, proximity to hospital, length of stay, lower extremity open procedure or amputation, and discharge destination persisted in multivariable logistic regression (P < .05). CONCLUSIONS: To reduce readmission rates effectively, institutions must identify high-risk patients. Efforts should focus on subgroups undergoing selected interventions (amputations, lower extremity revascularization), those with urgent admissions, and patients with extended hospital stays. Patients in need of postacute care upon discharge are especially prone to readmission, requiring special attention to discharge planning and coordination of postdischarge care. By focusing on subgroups at risk for readmission, preventative resources can be efficiently targeted.

Postdischarge outcomes after endovascular abdominal aortic aneurysm repair.

OBJECTIVE: Perioperative outcomes after endovascular repair (EVAR) of abdominal aortic aneurysms (AAA) have been rigorously studied; however, inpatient and postdischarge outcomes have not been separately analyzed. The objective of this study was to examine postdischarge 30-day outcomes after elective EVAR. METHODS: Patients who underwent an elective EVAR for AAA (n = 11,229) were identified from the American College of Surgeons 2005-2010 National Surgical Quality Improvement Project database. Univariable and multivariable logistic regression analyses were performed. RESULTS: The median length of hospital stay was 2 days (interquartile range, 1-3 days). Overall 30-day mortality was 1.0% (n = 117), with 31% (n = 36) of the patients dying after discharge. Overall 30-day morbidity was 10.7% (n = 1204), with 40% (n = 500) of the morbidities being postdischarge. The median time of death and complication was 9 and 3 days, respectively, after surgery. Eighty-eight percent of the wound infections (n = 205 of 234), 33% of pneumonia (n = 44 of 133), and 55% of venous thromboembolism (n = 36 of 65) were postdischarge. Multivariable analyses showed age, congestive heart failure, admission from nursing facility, postoperative pneumonia, myocardial infarction, and renal failure were independently associated with postdischarge mortality, and peripheral arterial disease, female gender, previous cardiac surgery, age, smoking, and diabetes with postdischarge morbidity (P < .05 for all). CONCLUSIONS: Patient characteristics associated with a higher risk for postdischarge adverse events after EVAR were identified. Whether improved predischarge surveillance and close postdischarge follow-up of identified high-risk patients will further improve 30-day outcomes after EVAR needs to be prospectively studied.

Development and validation of a risk calculator for predicting postoperative pneumonia.

OBJECTIVE: To identify preoperative factors associated with an increased risk of postoperative pneumonia and subsequently develop and validate a risk calculator. PATIENTS AND METHODS: The American College of Surgeons' National Surgical Quality Improvement Program, a multicenter, prospective data set (2007-2008) was used. Univariate and multivariate logistic regression analyses were performed. The 2007 data set (N=211,410) served as the training set, and the 2008 data set (N=257,385) served as the validation set. RESULTS: In the training set, 3825 patients (1.8%) experienced postoperative pneumonia. Patients who experienced postoperative pneumonia had a significantly higher 30-day mortality (17.0% vs 1.5%; P<.001). On multivariate logistic regression analysis, 7 preoperative predictors of postoperative pneumonia were identified: age, American Society of Anesthesiologists class, chronic obstructive pulmonary disease, dependent functional status, preoperative sepsis, smoking before operation, and type of operation. The risk model based on the training data set was subsequently validated on the validation data set, with model performance being very similar (C statistic: 0.860 and 0.855, respectively). The high C statistic indicates excellent predictive performance. The risk model was used to develop an interactive risk calculator. CONCLUSION: Preoperative variables associated with an increased risk of postoperative pneumonia include age, American Society of Anesthesiologists class, chronic obstructive pulmonary disease, dependent functional status, preoperative sepsis, smoking before operation, and type of operation. The validated risk calculator provides a risk estimate for postoperative pneumonia and is anticipated to aid in surgical decision making and informed patient consent.

Development of a risk index for prediction of mortality after open aortic aneurysm repair.

OBJECTIVE: Open infrarenal abdominal aortic aneurysm (oAAA) repair is associated with significant morbidity and mortality. Although there has been a shift toward endovascular repair, many patients continue to undergo an open repair due to anatomic considerations. Tools currently existing for estimation of periprocedural risk in patients undergoing open aortic surgery have certain limitations. The objective of this study was to develop a risk index to estimate the risk of 30-day perioperative mortality after elective oAAA repair. METHODS: Patients who underwent elective oAAA repair (n = 2845) were identified from the American College of Surgeons' 2007 to 2009 National Surgical Quality Improvement Program (NSQIP), a prospective database maintained at >250 centers. Univariable and multivariable analyses were performed to evaluate risk factors associated with 30-day mortality after oAAA repair and a risk index was developed. RESULTS: The 30-day mortality after oAAA repair was 3.3%. Multivariable analysis identified six preoperative predictors of mortality, and a risk index was created by assigning weighted points to each predictor using the ß-coefficients from the regression analysis. The predictors included dyspnea (at rest: 8 points; on moderate exertion: 2 points; none: 0 points), history of peripheral arterial disease requiring revascularization or amputation (3 points), age >65 years (3 points), preoperative creatinine >1.5 mg/dL (2 points), female gender (2 points), and platelets <150,000/mm(3) or >350,000/mm(3) (2 points). Patients were classified as low (<7%), intermediate (7%-15%), and high (>15%) risk for 30-day mortality based on a total point score of <8, 8 to 11, and >11, respectively. There were 2508 patients (88.2%) patients in the low-risk category, 278 (9.8%) in the intermediate-risk category, and 59 (2.1%) in the high-risk category. CONCLUSIONS: This risk index has excellent predictive ability for mortality after oAAA repair and awaits validation in subsequent studies. It is anticipated to aid patients and surgeons in informed patient consent, preoperative risk assessment, and optimization.

Preoperative anemia is an independent predictor of postoperative mortality and adverse cardiac events in elderly patients undergoing elective vascular operations.

OBJECTIVE: The objective of this study was to assess the impact of preoperative anemia (hematocrit <39%) on postoperative 30-day mortality and adverse cardiac events in patients 65 years or older undergoing elective vascular procedures. BACKGROUND: Preoperative anemia is associated with adverse outcomes after cardiac surgery, but its association with postoperative outcomes after open and endovascular procedures is not well established. Elderly patients have a decreased tolerance to anemia and are at high risk for complications after vascular procedures. METHODS: Patients (N = 31,857) were identified from the American College of Surgeons' 2007-2009 National Surgical Quality Improvement Program-a prospective, multicenter (>250) database maintained across the United States. The primary and secondary outcomes of interest were 30-day mortality and a composite end point of death or cardiac event (cardiac arrest or myocardial infarction), respectively. RESULTS: Forty-seven percent of the study population was anemic. Anemic patients had a postoperative mortality and cardiac event rate of 2.4% and 2.3% in contrast to the 1.2% and 1.2%, respectively, in patients with hematocrit within the normal range (P < 0.0001). On multivariate analysis, we found a 4.2% (95% confidence interval, 1.9-6.5) increase in the adjusted risk of 30-day postoperative mortality for every percentage point of hematocrit decrease from the normal range. CONCLUSIONS: The presence and degree of preoperative anemia are independently associated with 30-day death and adverse cardiac events in patients 65 years or older undergoing elective open and endovascular procedures. Identification and treatment of anemia should be important components of preoperative care for patients undergoing vascular operations.

In-hospital and postdischarge venous thromboembolism after vascular surgery.

OBJECTIVE: Recent single-center reports demonstrate a high (up to 10%) incidence of postoperative venous thromboembolism (VTE) after major vascular surgery. Moreover, vascular patients rarely receive prolonged prophylaxis despite evidence that it reduces thromboembolic events after discharge. This study used a national, prospective, multicenter database to define the incidence of overall and postdischarge VTE after major vascular operations and assess risk factors associated with VTE development. METHODS: Patients with VTE who underwent elective vascular procedures (n = 45,548) were identified from the 2007-2009 National Surgical Quality Improvement Program (NSQIP) database. The vascular procedures included carotid endarterectomy (CEA; n = 20,785), open thoracoabdominal aortic aneurysm (TAAA) repair (n = 361), thoracic endovascular aortic repair (TEVAR; n = 732), open abdominal aortic (OAA) surgery (n = 6195), endovascular aneurysm repair (EVAR; n = 7361), and infrainguinal bypass graft (BPG; n = 10,114). Univariable and multivariable analyses were performed to ascertain risk factors associated with VTE. RESULTS: VTE was diagnosed in 187 patients (1.3 %) who underwent aortic surgery, with TAAA repair having the highest rate of VTE (4.2%), followed by TEVAR (2.2%), OAA surgery (1.7%), and EVAR (0.7%). In this subgroup, pulmonary embolisms (PE) were diagnosed in 52 (0.4%) and deep venous thrombosis (DVT) in 144 (1%). VTE rates were 1.0% and 0.2% for patients who underwent a BPG or CEA, respectively. Forty-one percent of all VTEs were diagnosed after discharge. The median (interquartile range) number of days from surgery to PE and DVT were 10 (5-15) and 10 (4-18), respectively. On multivariable analyses, type of surgical procedure, totally dependent functional status, disseminated cancer, postoperative organ space infection, postoperative cerebrovascular accident, failure to wean from ventilator ≤48 hours, and return to the operating room were significantly associated with development of VTE. In those experiencing a DVT or PE, overall mortality increased from 1.5% to 6.2% and from 1.5% to 5.7% respectively (P < .05 for both). CONCLUSIONS: Postoperative VTE is associated with the type of vascular procedure and is highest after operations in the chest and abdomen/pelvis. About 40% of VTE events in elective vascular surgery patients were diagnosed after discharge, and the presence of VTE was associated with a quadrupled mortality rate. Future studies should evaluate the benefit of DVT screening and postdischarge VTE prophylaxis in high-risk patients.

Impact of COPD on postoperative outcomes: results from a national database.

BACKGROUND: Although COPD affects large sections of the population, its effects on postoperative outcomes have not been rigorously studied. The objectives of this study were to describe the prevalence of COPD in patients undergoing surgery and to analyze the associations between COPD and postoperative morbidity, mortality, and hospital length of stay. METHODS: Patients with COPD who underwent surgery were identified from the National Surgical Quality Improvement Program database (2007-2008). Univariate and multivariate analyses were performed on this multicenter, prospective data set (N = 468,795). RESULTS: COPD was present in 22,576 patients (4.82%). These patients were more likely to be older, men, white, smokers, and taking corticosteroids and had a lower BMI (P < .0001 for each). Median length of stay was 4 days for patients with COPD vs 1 day in those without COPD (P < .0001). Thirty-day morbidity rates were 25.8% and 10.2% for patients with and without COPD, respectively (P < .0001). Thirty-day death rates were 6.7% and 1.4% for patients with and without COPD, respectively (P < .0001). After controlling for > 50 comorbidities through logistic regression modeling, COPD was independently associated with higher postoperative morbidity (OR, 1.35; 95% CI, 1.30-1.40; P < .0001) and mortality (OR, 1.29; 95% CI, 1.19-1.39; P < .0001). Multivariate analyses with each individual postoperative complication as the outcome of interest showed that COPD was associated with increased risk for postoperative pneumonia, respiratory failure, myocardial infarction, cardiac arrest, sepsis, return to the operating room, and renal insufficiency or failure (P < .05 for each). CONCLUSIONS: COPD is common among patients undergoing surgery and is associated with increased morbidity, mortality, and length of stay.