The outcome in the United States after thoracoabdominal aortic aneurysm repair, renal artery bypass, and mesenteric revascularization.

OBJECTIVES: The purpose of this study was to determine outcome and identify predictors of death after thoracoabdominal aortic aneurysm (TAA) repair, renal artery bypass (RAB), and revascularization for chronic mesenteric ischemia (CMI). PATIENTS AND METHODS: In this retrospective analysis, data were obtained from the Nationwide Inpatient Sample, a 20% all-payer stratified sample of hospitals in the United States during 1993 to 1997. Patients were identified by the presence of a diagnostic or procedure code from the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM). The main outcomes we examined were death, ICD-9-CM -based complications, length of stay, hospital charges, and disposition. A multivariate model was constructed to predict death. RESULTS: A total of 2934 patients were identified (TAA, 540; RAB, 2058; CMI, 336) in the database. The mean age was comparable (TAA, 69 +/- 9 years; RAB, 66 +/- 12 years; CMI, 66 +/- 11 years), but the breakdown between the sexes varied by procedure (male: TAA, 53%; RAB, 55%; CMI, 24%). The mortality rate (TAA, 20.3%; RAB, 7.1%; CMI, 14.7%), complication rate (TAA, 62.2%; RAB, 37.4%; CMI, 44.6%), and the percentage of patients discharged to another institution (TAA, 21.2%; RAB, 9.3%; CMI, 12.0%) were clinically significant for all procedures. The mortality rate for RAB was greater when performed concomitant with an aortic reconstruction (4.4% vs 8.3%). All three procedures were resource intensive as reflected by the median length of stay (TAA, 14 days; RAB, 9 days; CMI, 14 days) and median hospital charges (TAA, $64,493; RAB, $36,830; CMI, $47,390). The multivariate model identified several variables for each procedure that had an impact on the predicted mortality rate (TAA, 14%-76%; RAB, < 1%-46%; CMI, < 2%-87%). CONCLUSIONS: The operative mortality rates across the United States for patients undergoing TAA repair and RAB are greater than commonly reported in the literature and mandate reexamining the treatment strategies for these complex vascular problems.

Experience in the United States with intact abdominal aortic aneurysm repair.

OBJECTIVES: The purpose of this study was to determine the current outcome in the United States and to identify predictors of mortality and "bad outcome" after open, intact abdominal aortic aneurysm (AAA) repair. METHODS: In a retrospective analysis, data were obtained from the Nationwide Inpatient Sample during 1994-1996. The Nationwide Inpatient Sample is a 20% all-payer stratified sample of nonfederal United States hospitals. Patients older than 49 years were identified by the presence of primary diagnostic (441.4-intact AAA) and procedure (38.44-resection of abdominal aorta with replacement) codes of the International Classification of Diseases, Ninth Revision (ICD-9 ). In-hospital mortality rate, discharge disposition, bad outcome (death or discharge to an institution), complications (ICD-9 postoperative codes), length of stay, and charges were determined. The mortality rate and bad outcome were analyzed by the use of patient demographics (age, sex, race), patient comorbidities (ICD-9 diagnostic codes), calendar year, and hospital characteristics (size, location, teaching status) with univariate and multivariate analyses. RESULTS: We identified 16,450 intact AAAs repairs during the study years. The mean patient age was 72 +/- 7 (+/- SD) years, and most patients were male (79.7%) and white (94.6%). Most repairs were performed at large (67.3%), urban (92.5%), and nonteaching (66.7%) institutions. The in-hospital mortality rate was 4.2%, the overall complication rate was 32.4%, and 91.2% of patients were discharged home, whereas the bad outcome rate was 12.6%. The median length of stay was 8 days (mean, 10.0 +/- 8.1), and median hospital charges were $28,052 (mean, $35,681 +/- $33,006) in 1996 dollars. Multivariate analysis showed that the mortality rate (P <.05) increased with age (70-79 years, 1.8 odds ratio [OR] [95% CI, 1.4-2.3], > 79 years, 3.8 OR [95% CI, 2.9-4.9]), sex (female, 1.6 OR [95% CI, 1.3-1.9]), cerebral vascular occlusive disease (1.8 OR [95% CI, 1.3-2.5]), preoperative renal insufficiency (9.5 OR [95% CI, 7.7-11.7]), and more than three comorbidities (11.2 OR [95% CI, 3.6-35.4]). Multivariate analysis also showed that bad outcome was associated with the same variables in addition to hospital size (small/medium), year of procedure (1996), chronic obstructive pulmonary disease, and two to three comorbidities. CONCLUSIONS: Outcome after open repair of intact AAA across the United States is quite good. Older, sicker patients may benefit from nonoperative treatment or the potentially lower risk endovascular approaches.

Financial impact of tertiary care in an academic medical center.

OBJECTIVE: To analyze the financial impact of three complex vascular surgical procedures to both an academic hospital and a department of surgery and to examine the potential impact of decreased reimbursements. SUMMARY BACKGROUND DATA: The cost of providing tertiary care has been implicated as one potential cause of the financial difficulties affecting academic medical centers. METHODS: Patients undergoing revascularization for chronic mesenteric ischemia, elective thoracoabdominal aortic aneurysm repair, and treatment of infected aortic grafts at the University of Florida were compared with those undergoing elective infrarenal aortic reconstruction and carotid endarterectomy. Hospital costs and profit summaries were obtained from the Clinical Resource Management Office. Departmental costs and profit summary were estimated based on the procedural relative value units (RVUs), the average clinical cost per RVU ($33.12), surgeon charges, and the collection rate for the vascular surgery division (30.2%) obtained from the Faculty Group Practice. Surgeon work effort was analyzed using the procedural work RVUs and the estimated total care time. The analyses were performed for all payors and the subset of Medicare patients, and the potential impact of a 15% reduction in hospital and physician reimbursement was analyzed. RESULTS: Net hospital income was positive for all but one of the tertiary care procedures, but net losses were sustained by the hospital for the mesenteric ischemia and infected aortic graft groups among the Medicare patients. In contrast, the estimated reimbursement to the department of surgery for all payors was insufficient to offset the clinical cost of providing the RVUs for all procedures, and the estimated losses were greater for the Medicare patients alone. The surgeon work effort was dramatically higher for the tertiary care procedures, whereas the reimbursement per work effort was lower. A 15% reduction in reimbursement would result in an estimated net loss to the hospital for each of the tertiary care procedures and would exacerbate the estimated losses to the department. CONCLUSIONS: Caring for complex surgical problems is currently profitable to an academic hospital but is associated with marginal losses for a department of surgery. Economic forces resulting from further decreases in hospital and physician reimbursement may limit access to academic medical centers and surgeons for patients with complex surgical problems and may compromise the overall academic mission.

Impact of race on the treatment for peripheral arterial occlusive disease.

PURPOSE: The purpose of this study was to determine the impact of race on the treatment of peripheral artery occlusive disease (PAOD) and to examine the role of access to care and disease distribution on the observed racial disparity. METHODS: The study was performed as a retrospective analysis of hospital discharge abstracts from 1992 to 1995 in 202 non-federal, acute-care hospitals in the state of Florida. The subjects were patients older than 44 years of age who underwent major lower extremity amputation or revascularization (bypass grafting or angioplasty) for PAOD. The main outcome measures were incidence of intervention, incidence per demographic group, multivariate predictors of amputation versus revascularization, multivariate predictors of amputation versus revascularization among those patients with access to sophisticated care (hospital with arteriographic capabilities), and multivariate predictors of surgical bypass graft type (aortoiliac vs infrainguinal). RESULTS: A total of 51,819 procedures (9.1 per 10,000 population) were performed for PAOD during the study period and included 15,579 major lower extremity amputations (30.1%) and 36,240 revascularizations (69.9%). Although the incidence of a procedure for PAOD was comparable between African Americans and whites (9.0 vs 9.6 per 10, 000 demographic group), the incidence of amputation (5.0 vs 2.5 per 10,000 demographic group) was higher and the incidence of revascularization (4.0 vs 7.1 per 10,000 demographic group) was lower among African Americans. Furthermore, multivariate analysis results showed that African Americans (odds ratio, 3.79; 95% confidence interval [CI], 3.34 to 4.30) were significantly more likely than whites to undergo amputation as opposed to revascularization. The secondary multivariate analyses results revealed that African Americans (odds ratio, 2.29; 95% CI, 1.58 to 3. 33) were more likely to undergo amputation among those patients (n = 9193) who underwent arteriography during the procedural admission and to undergo infrainguinal bypass grafting (odds ratio, 2.00; 95% CI, 1.48 to 2.71) among those patients (n = 27,796) who underwent surgical bypass grafting. CONCLUSION: There is a marked racial disparity in the treatment of patients with PAOD that may be caused in part by differences in the severity of disease or disease distribution.

Impact of a clinical pathway for elective infrarenal aortic reconstructions.

OBJECTIVE: To determine the impact of a clinical pathway for elective infrarenal aortic reconstruction on outcome, resource utilization, and cost in a university medical center. SUMMARY BACKGROUND DATA: Clinical pathways have been reported to control costs, reduce resource utilization, and maintain or improve the quality of patient care, although their use during elective aortic reconstructions remains unresolved. METHODS: A clinical pathway was developed for elective infrarenal aortic reconstructions by a multidisciplinary group comprised of representatives from each involved service. The prepathway practice and costs were analyzed and an efficient, cost-effective practice with specific outcome measures was defined. The impact of the pathway was determined by retrospective comparison of outcome, resource utilization, and cost (total and direct variable) between the pathway patients (PATH, n = 45) and a prepathway control group (PRE, n = 20). RESULTS: There were no significant differences in the patient demographics, comorbid conditions, operative indications, or type of reconstruction between the groups. There were no operative deaths and the overall complication rate (PRE, 35% vs. PATH, 34%) was similar. The pathway resulted in significant decreases in the total length of stay and preoperative length of stay and a trend toward a significant decrease (p = 0.08) in the intensive care length of stay for the admission during which the operation was performed. The pathway also resulted in significant decreases in both direct variable and total hospital costs for this admission, as well as a significant decrease in the overall direct variable and total hospital costs for the operative admission and the preoperative evaluation (< or =30 days before operative admission). Despite these reductions, the discharge disposition, 30-day readmissions, and number of postoperative clinic visits within 90 days of discharge were not different. CONCLUSIONS: Implementation of a clinical pathway for elective infrarenal aortic reconstructions dramatically decreased resource utilization and hospital costs without affecting the quality of patient care and did not appear to shift the costs to another setting.

Utility of magnetic resonance arteriography for distal lower extremity revascularization.

PURPOSE: Magnetic resonance arteriography (MRA) of the lower extremities affords several possible advantages over conventional contrast arteriography (CA). We hypothesized that MRA of the infrageniculate vessels was sufficiently accurate to replace CA before revascularization procedures in patients with limb-threatening ischemia. METHODS: Fifty-three extremities in 49 patients were prospectively evaluated before attempted infrageniculate revascularization procedures with preoperative infrageniculate time-of-flight MRA (cost, $170/study) and standard contrast arteriography (cost, $1310/study) of the aortoiliac and runoff vessels. Independent operative plans were formulated based on the MRA and CA results before the revascularization procedure. Intraoperative, prebypass arteriograms (IOA; cost, $46/study) were obtained in all patients to confirm the adequacy of the distal runoff. The preoperative plans formulated by the results of MRA and CA were compared with the actual procedure performed based on the IOA. All arteriograms (CA, MRA, IOA) were reviewed after the operation by two independent reviewers, and the number of patent vessel segments and those with < 50% stenosis was determined. RESULTS: Revascularization procedures were performed in 44 of 53 extremities (83%), and amputation was performed in nine extremities (17%) because of an absence of a suitable bypass target. The CA and MRA were equally effective in predicting the optimal operative plans as determined from IOA (CA, 42 of 53 [77%] vs MRA, 40 of 53 [75%]; p = 0.79). More patent vessel segments were seen on CA than MRA (reviewer A, 229 vs 174, kappa = 0.32; reviewer B, 321 vs 314, kappa = 0.46); however, a comparable number of segments were seen if the vessels of the foot were excluded. The accuracy (reviewer A, 78% vs 68%, p = 0.003; reviewer B, 75% vs 67%, p = 0.003) and sensitivity (reviewer A, 69% vs 51%, p = 0.001; reviewer B, 68% vs 46%, p = 0.0001) of CA relative to IOA were superior to those of MRA, although the specificity was comparable (reviewer A, 86% vs 90%, p = 0.31; reviewer B, 82% vs 87%, p = 0.52). The combination of MRA and IOA would have resulted in the optimal operative plan in 51 of the 53 cases (96%) and was comparable with CA and IOA (53 of 53; 100%; p = 0.50). Substitution of MRA and IOA for CA and IOA could potentially have saved an estimated $60,420. CONCLUSIONS: The combination of MRA and IOA provides an accurate, cost-efficient strategy for visualization of the infrageniculate vessels before revascularization procedures.

Improving the cost-effectiveness of carotid endarterectomy.

PURPOSE: Carotid endarterectomy (CEA) has been shown to significantly reduce the risk of stroke caused by carotid artery stenosis. Limiting the costs of CEA without increasing the risks will improve the cost-effectiveness of this procedure. METHODS: Results were prospectively collected from 63 consecutive CEAs performed in 60 patients who were entered into a clinical pathway for CEA that included avoidance of cerebral arteriography, preferential use of regional anesthesia, selective use of the intensive care unit (ICU), and early hospital discharge. The mortality rate, complications, hospital costs, and net income in these patients were then compared with results from 45 CEAs performed in 42 consecutive patients immediately before beginning the CEA pathway. Age, comorbid risk factors, incidence of symptoms, and degree of carotid artery stenosis were similar in both patient groups. RESULTS: The rates of mortality and complications associated with CEA were low (mortality rate, 0%; stroke, 0.9%; transient ischemic attack, 2.8%) and did not vary between the two groups. Implementation of the CEA pathway resulted in significant (p < 0.001) reductions in the use of arteriography (74% to 13%), general anesthesia (100% to 24%), ICU use (98% to 30%), and mean hospital length of stay (5.8 days to 2.0 days). These changes resulted in a 41% reduction in mean total hospital cost ($9652 to $5699) and a 124% increase in mean net hospital income ($1804 to $4039) per CEA (p < 0.01). For the 39 patients (62%) who achieved all elements of the CEA pathway, the mean hospital length of stay was 1.3 days, the mean hospital cost was $4175, and the mean hospital income was $4327. CONCLUSIONS: Costs associated with CEA can be reduced substantially without increased risk. This makes CEA an extremely cost-effective treatment of carotid disease against which new therapeutic approaches must be measured.

Intraoperative prebypass arteriography for infrageniculate revascularization.

BACKGROUND: Selection of the optimal distal target for infrageniculate arterial revascularization remains difficult in patients with multilevel occlusive disease due to poor visualization of the distal vasculature by preoperative arteriography. Prebypass, intraoperative arteriography (IOA) with direct injection of contrast into the infrageniculate arteries may improve distal arterial visualization and bypass target selection. METHODS: One hundred fourteen extremities in 104 consecutive patients requiring infrageniculate bypass were prospectively studied. All patients underwent preoperative contrast arteriography (CA) of the aortoiliac and lower extremity arteries using iodinated and/or CO2 contrast and digital subtraction techniques. IOAs were obtained at operation to confirm the adequacy of the distal runoff from the predicted bypass target and to identify potentially superior targets. The preoperative plan formulated from the CA was compared to the actual procedure performed based on the IOA. The CA and IOA were also independently reviewed postoperatively by two blinded vascular surgeons to determine the number of patent vessel segments visualized and the number of segments with <50% stenosis. RESULTS: Revascularization was done in 105 of 114 extremities (92%), whereas amputation was required as the initial procedure in 9 patients (8%). The IOA altered the operative plan based on the CA in 27 of 144 patients (24%). Changes in the planned bypass procedures included selection of a more distal anastomotic site in 13 of 102 patients (13%), selection of a more proximal anastomotic site in 4 of 102 (4%), selection of a different artery for the distal anastomosis in 3 of 102 (3%), and amputation rather than bypass in 2 of 102 patients (2%) with no suitable distal bypass target on the IOA. The IOA also resulted in bypass rather than planned amputation in 5 of 12 patients (42%) deemed unreconstructable on the preoperative CA. A mean of 13 minutes was required for IOA and an adequate study was obtained on the first attempt in 98 of 144 patients (86%). On postoperative review, more patent vessel segments but fewer segments with <50% stenosis were identified on the IOA compared to the CA. CONCLUSIONS: Prebypass intraoperative arteriography facilitates selection of the optimal distal bypass target during infrageniculate revascularization and can result in initial limb salvage in select patients deemed unreconstructable by preoperative contrast arteriography.

Intraoperative autologous transfusion during elective infrarenal aortic reconstruction: a decision analysis model.

PURPOSE: The use of intraoperative autologous transfusion devices expanded during the last decade as a result of the increased awareness of transfusion-associated complications. This study was designed to determine whether routine use of an intraoperative autologous transfusion device (Haemonetics Cell Saver [CS]) during elective infrarenal aortic reconstructions is cost-effective ($50,000/QALYs threshold). METHODS: A decision analysis tree was constructed to model all of the complications that are associated with red blood cell replacement during aortic reconstructions for both abdominal aortic aneurysm (AAA) and aortoiliac occlusive disease (AIOD). It was assumed that a unit of CS return (CSR; 250 ml/unit) equaled a unit of packed red blood cells (PRBCs) and that all CS transfusions were necessary. Transfusion requirements (AAA:PRBC = 2.8 +/- 3.2 units, CSB = 3.7 +/- 3.2 units; AIOD:PRBC = 3.1 +/- 3.0 units, CSR = 2.1 +/- 1.7 units) were determined from retrospective review of all elective aortic reconstructions (AAA, N = 63; AIOD, N = 75) from Jan. 1991 to June 1995 in which the CS was used (82.1% of all reconstructions). Risk of allogenic transfusion-related complications (transfusion reaction, hepatitis B, hepatitis C, human immunodeficiency virus, human T-cell lymphotropic virus types I and II) and their associated treatment costs (expressed in dollars and quality-adjusted life years (QALYs) were obtained from the medical literature, institutional audit, and a consensus of physicians. RESULTS: Routine use of the CS during elective infrarenal aortic reconstructions was not cost-effective in our practice. Use during reconstructions for AAA repairs cost $263.75 but added only 0.00218 QALYs, for a rate of $120,794/QALY. Use during reconstructions for AIOD was even more costly at $356.68 and provided even less benefit at 0.00062 QALYs, for a rate of $578,275/QALY. The sensitivity analyses determined that the routine use of the CS would be cost-effective in our practice only for AAA repairs if the incidence of hepatitis C were tenfold greater than the baseline assumption. The model determined that CS was cost-effective if the CSR exceed 5 units during reconstructions for AAA and 6 units during reconstructions for AIOD. CONCLUSIONS: The routine use of the CS during elective infrarenal aortic reconstructions is not cost-effective. The use of the device should be reserved for a select group of aortic reconstructions, including those in which cost-effective salvage volumes are anticipated. Alternatively, the CS should be used as a reservoir and activated as a salvage device if significant bleeding is encountered.

Intraoperative autologous transfusion during elective infrarenal aortic reconstruction.

Intraoperative autologous transfusion devices have been purported to reduce allogenic transfusions and their associated complications. However, the value of their routine use during elective cardiovascular operations remains undefined. This study was designed to examine the efficacy of the Haemonetics Cell Saver (CS) during elective aortic reconstructions and identify predictors of clinically significant (> or = 500 cc) and cost-efficient (> or = 1250 cc) salvage volumes. The medical records of all patients undergoing elective infrarenal aortic reconstructions between January 1991 and June 1995 were retrospectively reviewed to determine blood loss, CS return, predictors of clinically significant/ cost-efficient CS returns, blood products transfused, and estimated cost per unit CS return. The CS was used for 138 (82.1%) of all reconstructions during the study period. Estimated blood loss (2127 +/- 1467 vs 1415 +/- 1047) and CS return (927 +/- 790 vs 515 +/- 408) were significantly greater in patients with aneurysms (AAA, N = 63) compared to those with aortoiliac occlusive disease (AIOD, N = 75). CS returns > or = 500 cc were common (79.4% AAA, 52.0% AIOD) and predictors of > or = 500 cc CS returns were large aneurysms (6.79 +/- 1.84 vs 5.72 +/- 0.71 cm) and male sex (82.0 vs 46.2%) in AAA patients and lower preoperative platelet counts (262 +/- 93 vs 311 +/- 113 K/mm3), concomitant renal revascularizations (20.5 vs 0%), and prolonged operative time (7.9 +/- 2.4 vs 6.9 +/- 2.1 hr) in AIOD patients. In contrast, CS returns > or = 1250 cc were relatively uncommon (28.6% AAA, 5.3% AIOD), and predictors of these CS returns were found only for AAA patients and included any concomitant vascular procedures (38.8 vs 15.6%) and the need for suprarenal aortic clamping (27.8 vs 6.7%). Despite the use of the CS, 73.8% of all patients required allogenic packed red blood cells with a mean of 3.0 +/- 3.1 units transfused in the perioperative period; no difference was seen between AAA and AIOD patients. The calculated cost for a unit of CS return was +128.77 for the AAA patients and +231.91 for the AIOD patients. Not using the CS and substituting the return with allogenic packed red blood cells would have saved +252.80 and +352.84 for the AAA and AIOD patients, respectively. Routine use of the CS during elective infrarenal aortic reconstructions is not cost efficient and should be abandoned. Use of the device should be reserved only for complex reconstruction.

Visceral ischemia and organ dysfunction after thoracoabdominal aortic aneurysm repair. A clinical and cost analysis.

OBJECTIVE: Repair of thoracoabdominal aortic aneurysms (TAAAs) is associated with significant postoperative morbidity and mortality. Reperfusion of acutely ischemic abdominal viscera in animals leads to release of multiple factors that cause local and distant organ damage, and similar phenomena occurring in humans after TAAA repair could contribute to the high morbidity/mortality and cost associated with this procedure. METHODS: Twenty-nine patients undergoing elective TAAA repair were studied prospectively. Preoperative organ dysfunction and intraoperative risk factors (cross-clamp time, blood loss, operative time) were assessed and compared with postoperative organ dysfunction (defined as: pulmonary, positive pressure ventilation for > 7 days; renal, increase in serum creatinine > 2.0 mg/dL over baseline; hepatic, lactate dehydrogenase > 500 international units and total bilirubin > 3.0 mg/dL or serum transaminase level > 200 international units; hematopoietic, platelet count > 50 K or leukocyte count > 4.5 K, mortality, and costs. RESULTS: No relationship between preoperative organ dysfunction, blood loss, or operative time and postoperative organ dysfunction or mortality was seen; however, cross-clamp times > 40 minutes were associated with a significantly greater incidence of pulmonary (59%), renal (47%), hepatic (35%), and hematopoietic (47%) dysfunction. In addition, multiple-organ dysfunction (> 2 organ systems) was more common after > 40 minutes of visceral ischemia and led to significantly greater overall hospital ($88,465 + $76,155 vs. $41,782 + $31,244) and intensive care unit ($26,726 + $28,256 vs. $11,234 + $12,146) costs (p < 0.01, Mann-Whitney U test). Mortality associated with leukopenia was 67% compared with 4% without leukopenia (p < 0.01). CONCLUSION: Increasing durations of acute visceral ischemia led to significant multiple organ dysfunction after TAAA repair. Methods of limiting visceral ischemia or the systemic effects of visceral ischemia may decrease both the morbidity and mortality and the overall hospital cost associated with this procedure.