Quantifying the risk-adjusted hospital costs of postoperative complications after lower extremity bypass in patients with claudication.

OBJECTIVE: Increasing evidence has shown that the risks associated with surgical revascularization for intermittent claudication outweigh the benefits. The aim of our study was to quantify the cost of care associated with perioperative complications after elective lower extremity bypass (LEB) in patients presenting with intermittent claudication. METHODS: All patients undergoing first-time LEB for claudication in the Healthcare Database (2009-2015) were included. The primary outcome was in-hospital postoperative complications, including major adverse limb events (MALE), major adverse cardiac events (MACE), acute kidney injury, and wound complications. The overall crude hospital costs are reported, and a generalized linear model with log link and inverse Gaussian distribution was used to calculate the predicted hospital costs for specific complications. RESULTS: Overall, 7154 patients had undergone elective LEB for claudication during the study period. The median age was 66 years (interquartile range, 59-73 years), 67.5% were male, and 75.3% were white. Two thirds of patients (61.2%) had Medicare insurance, followed by private insurance (26.9%), Medicaid (7.7%), and other insurance (4.2%). In-hospital complications occurred in 8.5% of patients, including acute kidney injury in 3.0%, MALE in 2.8%, wound complications in 2.3%, and MACE in 1.0%. The overall median crude hospital cost was $11,783 (interquartile range, $8911-$15,767) per patient. The incremental increase in cost associated with a postoperative complication was significant, ranging from $6183 (95% confidence interval, $4604-$7762) for MALE to $10,485 (95% confidence interval, $6529-$14,441) for MACE after risk adjustment. CONCLUSIONS: Postoperative complications after elective LEB for claudication are not uncommon and increase the in-hospital costs by 46% to 78% depending on the complication. Surgical revascularization for claudication should be used sparingly in carefully selected patients.

Real-world cost analysis of endovascular repair versus open repair in patients with nonruptured abdominal aortic aneurysms.

BACKGROUND: The aim of this study was to provide a nationwide, all-payer, real-world cost analysis of endovascular aortic aneurysm repair (EVAR) versus open aortic aneurysm repair (OAR) in patients with nonruptured abdominal aortic aneurysms (non-rAAA). METHODS: All non-rAAA patients registered between July 2009 and March 2015 in the Premier Healthcare Database were analyzed. The Student t-test and the χ2 test were used for continuous and categorical variables, respectively; median value comparisons were done with the Wilcoxon-Mann-Whitney rank-sum test. The in-hospital absolute mean total cost (sum of fixed cost and variable cost) and subcategories were analyzed after adjustment for inflation at July 2015. Fixed costs included all overhead costs while variables costs included in-hospital services including procedures, room and board, services provided by hospital staff, and pharmacy costs. Total cost was stratified based on admission type (emergency vs nonemergency), 75th percentile of length of hospital stay among individual procedures (expected vs extended stay), mortality, and complications. Student t-test and Fisher's analysis of variance were used for comparing mean cost. Year-wise comparison of mean cost was done with analysis of variance to look for a trend over time. RESULTS: Our study cohort included 38,809 non-rAAA patients (33,171 EVAR and 5638 OAR). The mean total cost of index admission was lower in EVAR in comparison with OAR ($32,052 vs $36,091; P < .001), with lower fixed costs ($11,309 vs $16,818; P < .001) and higher variable costs ($20,743 vs $19,272; P < .001). Cost of pharmacy, labor, operating room, room and board and other costs were significantly higher with OAR, whereas the supply cost was higher with EVAR. The expected hospital length of stay of patients who underwent EVAR was associated with a higher total cost ($27,271 vs $25,680; P < .001) and a higher variable cost ($18,186 vs $13,671; P < .001) than OAR patients. However, the extended hospital stay of patients who underwent EVAR had lower costs in all categories compared with the extended length of stay of those who underwent OAR. Mortality associated with EVAR was costlier than OAR associated mortality (mean $72,483 vs $59,804; P = .017). From 2009 to 2014, the mean total cost of EVAR increased significantly by 18.5% ($28,745 vs $34,049; P < .001) owing to a 7.8% increase in fixed costs ($10,931 vs $11,789; P < .001) and a 25.0% increase in variable costs ($17,804 vs $22,257; P < .001). The mean total cost OAR remained stable over time. CONCLUSIONS: Overall hospitalization costs associated with EVAR of non-rAAA was lower than the hospitalization cost of OAR. Interestingly, we found that, among patients who had an expected hospital length of stay, the hospitalization cost after OAR was significantly lower than after EVAR. The average hospitalization cost of OAR was stable during the 5 years study period, whereas the hospitalization cost of EVAR increased significantly over time. Further studies are required to identify reasons for increased costs associated with EVAR.

Elective infrainguinal lower extremity bypass for claudication is associated with high postoperative intensive care utilization.

BACKGROUND: The overall use of intensive care units (ICUs) in the United States has been steadily increasing and is associated with tremendous health care costs. We suspect that the burden of ICU utilization after elective infrainguinal lower extremity bypass (LEB) procedures is high, despite relatively low risks of complications in the immediate postoperative period. We sought to identify the burden of ICU utilization after elective LEB in patients with claudication. METHODS: We queried the Premier Healthcare Database for all adult patients undergoing first recorded elective infrainguinal LEB for claudication from 2009 to 2015. Baseline characteristics and ICU utilization on postoperative day 0 (POD 0) were identified for each patient using Premier room and board chargemaster codes. A bivariate logistic regression was performed and postestimation concordance statistics were calculated to identify predictors of postoperative ICU vs regular surgical floor admission immediately after surgery. RESULTS: There were 6010 patients who met the selection criteria, of whom 2772 (46.1%) were admitted to the ICU and 3238 (53.9%) to the regular surgical floor on POD 0. Whereas patient-level factors were responsible for minor differences found in postoperative admission to the ICU after elective LEB, hospital characteristics made up the majority of variation in admission practices. Specifically, patients undergoing elective infrainguinal LEB in rural, nonteaching, small hospitals and those in certain geographic regions were more likely to be admitted to the ICU than to the floor (all, P < .001). Patient-level factors were poorly predictive of admission to the ICU immediately postoperatively, with C statistics ranging from 0.50 to 0.53. In contrast, hospital-level factors had higher C statistics ranging from 0.51 to 0.66, with geographic location being the strongest predictor of post-LEB ICU admission. There were no significant differences in the incidence of postoperative wound complications, major adverse limb events, major adverse cardiac events, or in-hospital mortality between groups (all, P ≥ .32). The median total hospital cost was $2340 higher for ICU compared with floor admission ($13,273 [interquartile range, $10,136-$17,883] vs $10,927 [interquartile range, $8342-$14,523]; P < .001). CONCLUSIONS: Nearly half of patients are admitted to an ICU directly after elective infrainguinal LEB for claudication. This practice is associated with significantly higher hospital cost and is predominantly influenced by hospital-level rather than by patient-level factors. Perioperative morbidity and mortality were similar regardless of postoperative disposition. To minimize ICU utilization, postoperative care intensity should be determined by clinical severity of the patient rather than by hospital routine.

Risk factors and outcomes for bowel ischemia after open and endovascular abdominal aortic aneurysm repair.

OBJECTIVE: Bowel ischemia (BI) is a serious complication after abdominal aortic aneurysm (AAA) repair. We sought to identify the incidence and risk factors associated with the development of postoperative BI and the post-BI outcomes for patients undergoing open aortic repair (OAR) and endovascular aortic repair (EVAR) of AAAs. METHODS: A retrospective analysis was conducted for all patients who had undergone OAR or EVAR from 2003 to 2017 using the Vascular Quality Initiative database. Univariate (Student's t test, χ2, median) and multivariable (logistic regression) analyses were used to identify independent factors associated with postoperative BI and compare the post-BI in-hospital outcomes and mortality. RESULTS: We identified 45,474 patients who had undergone infrarenal AAA repair (OAR, 21.5%; EVAR, 78.5%). The overall incidence of postoperative BI was 1.9% (OAR, 6.2% vs EVAR, 0.8%; P < .001). OAR was associated with a threefold increased odds of BI compared with EVAR (adjusted odds ratio [aOR], 3.24; 95% confidence interval [CI], 2.49-4.22; P < .001). The independent factors associated with BI after OAR included older age (aOR per year of age, 1.02; 95% CI, 1.00-1.03), congestive heart failure (aOR, 1.44; 95% CI, 1.05-1.98), and ruptured aneurysm (aOR, 4.16; 95% CI, 2.98-5.81; P < .01 for all). We also found that transfusion ≥1 U (aOR, 1.69; 95% CI, 1.30-2.20), a transperitoneal approach (aOR, 2.13; 95% CI, 1.03-1.87), supraceliac clamping (aOR, 1.58; 95% CI, 1.08-2.33), and inferior mesenteric artery reimplantation (aOR, 1.41; 95% CI, 1.06-1.89) were associated with greater odds of BI after OAR (P < .01 for all). Similarly, we found that ruptured aneurysms, a longer operative time, and transfusion of ≥1 U of blood were associated with BI after EVAR (P < .001 for all). For both OAR and EVAR, the postoperative stay (median, 13 days [interquartile range (IQR), 7-26 days] vs 7 days [IQR, 5-10 days] and 11 days [IQR, 4-23 days] vs 1 day [IQR, 1-3 days], respectively) and 30-day mortality (35.0% vs 6.4% and 40.5% vs 1.9%, respectively) were significantly higher for patients with BI (P < .001 for all). The predictors of mortality for patients with BI were surgical management (aOR, 2.05; 95% CI, 1.28-3.30), older age (aOR, 1.05; 95% CI, 1.02-1.07), symptomatic aneurysm (aOR, 1.26; 95% CI, [0.60-2.62), ruptured aneurysm (aOR, 2.23; 95% CI, 1.43-3.48), longer operative time (aOR, 1.11; 95% CI, 1.01-1.22), and postoperative renal complications (aOR, 2.98; 95% CI, 1.80-4.96; P < .05 for all). CONCLUSIONS: Confirming the results from previous studies, we found that BI is more common after a ruptured aneurysm and OAR. Other associated intraoperative factors included a transperitoneal approach, supraceliac clamping, and a reimplanted inferior mesenteric artery. More than one third of patients who developed postoperative BI in our cohort had died within 30 days after AAA repair. The factors associated with mortality after BI included surgical management and postoperative renal failure. A high index of suspicion for the signs and symptoms of BI should be maintained postoperatively for patients presenting with the risk factors identified.

Metabolic syndrome is associated with increased cardiac morbidity after infrainguinal bypass surgery irrespective of the use of cardiovascular risk-modifying agents.

BACKGROUND: The burden of metabolic syndrome (MetS) is increasing in the United States and is pervasive among patients with peripheral arterial disease. Whereas MetS has been implicated in the development of all types of cardiovascular disease and adverse outcomes after vascular interventions, little is known about how MetS influences perioperative outcomes of lower extremity bypass surgery and whether any negative effects can be modified by use of cardiovascular risk-modifying medications. METHODS: We used the National Surgical Quality Improvement Program vascular procedure-targeted database to capture patients undergoing infrainguinal bypass surgery between 2011 and 2015. We defined MetS using the modified MetS criteria: concomitant diabetes, hypertension, and body mass index >30 kg/m2. We used multivariable logistic regression analyses to examine the association between MetS and 30-day postoperative morbidity and mortality. We also examined whether preoperative aspirin, statin, and beta blockade modify the effects of MetS on 30-day postoperative outcomes. RESULTS: Of 10,053 patients who underwent infrainguinal bypass, 16% (1693) met criteria for MetS. After adjusting for covariates, MetS was significantly (P ≤ .05) associated with higher odds of postoperative myocardial infarction (odds ratio [OR], 1.66), infection (OR, 1.76), renal dysfunction (OR, 2.42), and length of stay (0.34 days). Within the MetS subgroup, there were no significant associations between use of preoperative cardiovascular risk-modifying agents and postoperative outcomes, with the exception of beta blockade and an increase in length of stay (0.33 days). CONCLUSIONS: Patients with MetS undergoing infrainguinal bypass surgery are at an increased risk of postoperative complications, including myocardial infarction. This elevated risk persists despite medical therapy with preoperative aspirin, statin, and beta blockade.

Effect of Beta Blockers on Mortality After Open Repair of Abdominal Aortic Aneurysm.

OBJECTIVE: To assess the effect of perioperative beta blocker (BB) use on postoperative in-hospital mortality after open repair of abdominal aortic aneurysm (OAR). BACKGROUND: Postoperative mortality after OAR ranges from 3.0% to 4.5%. Insight about the effect of BBs on postoperative mortality after OAR is currently lacking. METHODS: This is a retrospective study of patients undergoing OAR from 2009-Q3 to 2015-Q1 in the Premier Healthcare Database. The Premier Healthcare Database includes data representing 20% of all inpatient US discharges annually. Patients under 45 years, admitted after a trauma or who underwent multiple aortic repair procedures, were excluded. Multivariable logistic regression models were created to assess the relationship between perioperative BB use and postoperative in-hospital mortality. RESULTS: Of 6515 patients admitted for OAR, 5423 (83.2%) received perioperative BBs. Patients who received BBs were more likely to develop major adverse events compared with those who did not (45.6% vs 35.2%; P < 0.001); however, failure to rescue was lower among BB users (7.6% vs 19.5%; P < 0.001). In a multivariable logistic regression model, BB use was associated with 57% [odds ratio 0.43, 95% confidence interval (CI) 0.31-0.56, P = 0.001) and 81% (odds ratio 0.19, 95% CI 0.11-0.31, P < 0.001) lower odds of mortality among patients without and with a history of coronary artery disease, respectively. The predicted mortality (95% CI) for patients who did not receive BBs, or received low, intermediate, or high-intensity BBs was 11.6% (8.0%-15.2%), 5.4% (4.4%-6.5%), 2.5% (1.9%-3.0%), and 3.3% (2.3%-4.3%), respectively. CONCLUSIONS: In-hospital use of BBs was associated with a significant reduction in postoperative mortality after OAR. This is the first study to demonstrate a dose-response relationship between BBs and postoperative mortality after OAR.

Financial Impact of Acute Kidney Injury After Cardiac Operations in the United States.

BACKGROUND: Acute kidney injury (AKI) after major cardiac operations is a potentially avoidable complication associated with increased morbidity, death, and costly long-term treatment. The financial impact of AKI at the population level has not been well defined. We sought to determine the incremental index hospital cost associated with the development of AKI. METHODS: All patients undergoing coronary artery bypass grafting (CABG) or valve replacement operations, or both (clinical classification software codes 43 and 44), between 2008 and 2011 were identified from the Nationwide Inpatient Sample. AKI was identified using International Classification of Diseases, 9th Revision, Clinical Modification diagnosis codes (584.xx); patients with chronic renal failure were excluded. Mean total index hospitalization costs were compared between patients with and without AKI. RESULTS: At the population level, 1,078,036 individuals underwent major cardiac procedures from 2008 to 2011, with AKI developing in 105,648 (9.8%). Specifically, AKI developed in 8.0% of CABG, 11.4% of valve replacement, and 17.0% of CABG plus valve replacement patients (p < 0.001). Death was more common among patients with AKI vs those without (13.9% vs 1.3%, p < 0.001). Mean total index hospitalization cost was $77,178 for patients with AKI vs $38,820 for those without (p < 0.001). At the national level, the overall incremental annual index hospitalization cost associated with AKI was $1.01 billion. CONCLUSIONS: AKI developed in 1 in every 10 patients nationwide after a cardiac operation. Achieving a 10% reduction in AKI in this population would likely result in an annual savings of approximately $100,000,000 in index-hospital costs alone. Support for research on mechanisms to detect impending damage and prevent AKI may lead to reduced patient morbidity and death and to substantial health care cost savings.

Intensive care unit admission after endovascular aortic aneurysm repair is primarily determined by hospital factors, adds significant cost, and is often unnecessary.

BACKGROUND: A large proportion of endovascular aortic aneurysm repair (EVAR) patients are routinely admitted to the intensive care unit (ICU) for postoperative observation. In this study, we aimed to describe the factors associated with ICU admission after EVAR and to compare the outcomes and costs associated with ICU vs non-ICU observation. METHODS: All patients undergoing elective infrarenal EVAR in the Premier database (2009-2015) were included. Patients were stratified as ICU vs non-ICU admission according to location on postoperative day 0. Both patient-level (sociodemographics, comorbidities) and hospital-level (teaching status, hospital size, geographic location) factors were analyzed using univariate and multivariable logistic regression to determine factors associated with ICU vs non-ICU admission. Overall outcomes and hospital costs were compared between groups. RESULTS: Overall, 8359 patients underwent elective EVAR during the study period, including 4791 (57.3%) ICU and 3568 (42.7%) non-ICU admissions. Patients admitted to ICU were more frequently nonwhite and had more comorbidities, including congestive heart failure, coronary artery disease, chronic kidney disease, chronic obstructive pulmonary disease, diabetes, and hypertension, than non-ICU patients (all, P < .03). ICU admissions were more common in small (<300 beds), urban, and nonteaching hospitals and varied greatly depending on surgeon specialty and geographic region (P < .001). A pattern emerged when admission location was clustered by hospital; ICU patients were treated at hospitals where 96.7% (interquartile range, 84.5%-98.9%) of patients were admitted to ICU after EVAR, whereas non-ICU patients were treated at hospitals where only 7.5% (interquartile range, 4.9%-25.8%) were admitted to ICU after EVAR. A multivariable logistic regression model accounting for patient-, operative-, and hospital-level differences had a significantly lower area under the curve for predicting ICU admission after EVAR than a model accounting only for hospital factors (area under the curve, 0.76 vs 0.95; P < .001). The overall rate of adverse events was higher for ICU vs non-ICU patients (16.3% vs 13.7%; P < .001). Failure to rescue (2.9% vs 3.9%; P = .42) and in-hospital mortality (0.4% vs 0.4%; P = .81) were similar between groups. After adjusting for patient and hospital factors as well as for postoperative adverse events, ICU admission after EVAR cost $1475 (95% confidence interval, $768-2183) more than non-ICU admission (P < .001). CONCLUSIONS: Among patients undergoing elective EVAR, postoperative ICU admission is more closely associated with hospital practice patterns than with individual patient risk. Routine ICU admission after EVAR adds significant cost without reducing failure to rescue or in-hospital mortality.

Perioperative Outcomes of Thoracic Outlet Syndrome Surgical Repair in a Nationally Validated Database.

We evaluated the occurrence of thoracic outlet syndrome (TOS) and 30-day postoperative outcomes. Patients undergoing cervical/first rib resection surgery were identified in the American College of Surgeons National Surgical Quality Improvement Program database (2005-2013). Thoracic outlet syndrome types were then examined. Propensity score matching was performed to account for potential confounders; 1180 patients were explored during the study period, 1007 (85.3%) were of the neurogenic TOS (NTOS), 32 (2.7%) patients had arterial TOS (ATOS), and 141 (12.0%) patients had venous TOS (VTOS). Patients with ATOS were significantly older (median age [interquartile range, IQR]-NTOS: 34 [25-44], ATOS: 49.5 [42.5-57], VTOS: 34 [23-43]; P < .001). Median operating time was significantly longer for patients with ATOS. Median in-hospital stay was also longer for patients with ATOS (median length of in-hospital stay [LOS; IQR]-NTOS: 2 [1-4]; ATOS: 6 [3-7]; and VTOS: 5 [2-7] days; P < .001). Patients with VTOS showed twice longer LOS when compared to NTOS after matching. Presentation and treatment of TOS have been studied extensively at highly experienced centers.

"Halo effect" in trauma centers: does it extend to emergent colectomy?

BACKGROUND: Trauma centers (TCs) have been demonstrated to improve outcomes for some nontrauma surgical conditions, such as appendicitis, but it remains unclear if this extends to all emergency general surgery procedures. Using emergent colectomy in patients with diverticulitis as index condition, this study compared outcomes between TCs and nontrauma centers (NTCs). MATERIALS AND METHODS: The Nationwide Emergency Department Sample (2006-2011) was queried for patients ≥16 y with diverticulitis who underwent emergency surgical intervention. Outcomes included mortality, total charges, and length of stay (LOS). Mortality in TC and NTC was compared using logistic regression, controlling for patient, procedure, and hospital-level characteristics. Adjusted total charges and LOS were analyzed using generalized linear models with gamma and Poisson distributions, respectively. RESULTS: A total of 25,396 patients were included, 5189 (20.4%) were treated at TC and 20,207 (79.6%) at NTC. Median age and sex distribution were similar. Unadjusted proportional in-hospital mortality did not differ between TC and NTC; median charges and LOS were greater in TC. After adjusting, the odds of mortality were significantly higher in TC (odds ratio [OR], 1.23; 95% confidence interval [CI], 1.02-1.51; P = 0.003) as were mean charges and LOS (P < 0.001). CONCLUSIONS: The improved outcomes reported for other nontrauma conditions in TC were not observed for patients undergoing an emergent colectomy for diverticulitis after accounting for patient, procedure, and hospital-level characteristics. Future research is needed to assess differences in case mix between TC versus NTC and possible case-mix effects on outcomes to elucidate potential benefit of surgical care in a TC across the breadth of emergency general surgery conditions.