Faculty Bibliography

BACKGROUND: A randomized clinical trial from the United Kingdom (EVAR trial 2) comparing endovascular aortic aneurysm repair (EVAR) with no intervention found no advantage for EVAR in patients with high risk. This finding was predominantly caused by the substantial in-hospital mortality after EVAR (9%). HYPOTHESIS: The nationwide in-hospital mortality for patients with the highest risk undergoing EVAR in the United States is lower than that reported in EVAR trial 2. DESIGN: Population-based, cross-sectional study. SETTING: The 2001-2004 Nationwide Inpatient Sample. PATIENTS AND METHODS: The Nationwide Inpatient Sample identified EVAR procedures for nonruptured abdominal aortic aneurysms. Risk stratification was based on comorbidities and the Charlson comorbidity index, a validated predictor of in-hospital mortality after abdominal aortic aneurysms repairs. Weighted univariate and logistic regression analyses were used to determine the association between comorbidity measures and risk-adjusted in-hospital mortality. RESULTS: During the 4-year period, 65 502 EVARs were performed with an in-hospital mortality of 2.2%. Risk-adjusted in-hospital mortality rates ranged from 1.2% to 3.7%. Stratified analyses, including only elective EVAR procedures, revealed that in-hospital mortality was significantly higher in patients with the most severe comorbidities (1.7%) vs those with lower comorbidity (0.4%; P<.001). Patients with high risk had only a 1.6-fold increased risk of adjusted in-hospital mortality (odds ratio, 1.6; 95% confidence interval, 1.2-2.2) compared with patients with low risk. CONCLUSIONS: The EVAR procedure is currently being performed in the United States with low in-hospital mortality, even in patients with the highest risk. Therefore, EVAR should not be denied to high-risk patients with abdominal aortic aneurysms in the United States on the basis of the level I evidence from the United Kingdom study

Obesity independently increases the risk of pulmonary embolism (PE). We compare a superobese population (body mass index [BMI] > 55 kg/m(2)) undergoing open gastric bypasses (OGBs) with a similarly matched group of laparoscopic gastric bypasses (LGB) to see if the incidence of PE differs. We included all patients undergoing OGB (n = 193, average BMI = 51 kg/m(2)) at our institution by a single surgeon between July 1999 and April 2001. Thirty-one patients were superobese (BMI > 55 kg/m(2)). LGB was started at our institution in April 2001. Since that time 213 patients (average BMI = 52 kg/m(2)) have undergone the procedure. One hundred and nine patients were superobese. Pre- and postoperative prophylaxis included sequential compression stockings and subcutaneous heparin. Postoperatively, patients who developed signs of hypoxia, tachypnea, or tachycardia underwent a chest X-ray and spiral computed tomography. In addition, all patients who expired in the 30-day postoperative period underwent postmortem examination. Data were analyzed using the chi-squared test. In the OGB group, four patients (2.1%) developed PE. All occurred in superobese patients with a BMI > 55 kg/m(2). Three were fatal PEs and one was nonfatal. None of these patients had a prior history of deep vein thrombosis, PE, venous stasis disease, or pulmonary hypertension. In the LGB group, one patient (0.9%) had a nonfatal PE. This patient had a history of deep vein thrombosis. The incidence of PE was statistically higher in the superobese OGB group (P < 0.01). Despite the theoretical hindrance to venous return and vena caval compression observed with pneumoperitoneum, fewer PEs occurred in the laparoscopic group. Our data, however, suggest that patients with a BMI > 55 kg/m(2) might be at an increased risk for PE independent of operative approach

When ruptured abdominal aortic aneurysms (AAAs) are not treated, they cause death. In addition, ruptured abdominal aortic aneurysms (RAAAs) have high mortality (35%-70%) and morbidity rates when treated by standard open surgical methods. These high perioperative mortality and morbidity rates have not been substantially reduced despite the introduction of many improvements in open operative technique or perioperative care. Endovascular approaches to treat AAAs introduced in the early 1990s provided an opportunity to substantially alter treatment outcomes when rupture occurred. This article details how these endovascular approaches, which include endovascular stented grafts, can be applied to the treatment of RAAAs, and what advantages these new catheter-based approaches to treatment offer

OBJECTIVE: Patients undergoing open gastric bypass (OGB) for morbid obesity are at significant risk for pulmonary embolism (PE) despite the use of subcutaneous heparin injections and sequential compression devices. Prophylactic preoperative inferior vena cava (IVC) filter placement may reduce this risk. We report our experience with simultaneous IVC filter placement and OGB in an operating room setting. METHODS: From July 1999 to April 2001, 193 patients (group 1) underwent OGB. Eight patients had prophylactic intraoperative IVC filters placed for deep vein thrombosis, PE, or pulmonary hypertension. From May 2001 to January 2003, 181 patients (group 2) underwent OGB. There were 33 IVC filters placed for body mass index (BMI) greater than 55 kg/m2 in addition to the above-mentioned criteria. To confirm observations made in group 1 and 2 patients, from July 2003 to May 2005, 197 patients (group 3) underwent OGB, and patients with a BMI greater than 55 kg/m2 (n = 35) were offered IVC filter placement. Group 3A (n = 17) consented to IVC filter placement, and group 3B (n = 18) did not. RESULTS: Fifty-eight IVC filters were placed (100% technical success rate) with an increase in operating room time of 20 +/- 5 minutes. In group 1, the eight patients with IVC filters had a BMI greater than 55 kg/m2. There were four PEs (3 fatal and 1 nonfatal) in the other 185 patients, all which occurred in patients with BMIs greater than 55 kg/m2. In group 2, there were no PEs. The perioperative PE rate in these patients was reduced from 13% (4/31; 95% confidence interval [CI], 1.1%-25.7%) to 0% (0/33; 95% CI, 0%-8.7%). Perioperative mortality was reduced from 10% (3/31; 95% CI, 0%-20.0%) to 0% (0/33; 95% CI, 0%-8.7%). There were no pulmonary emboli or deaths related to PE in group 3A patients. Group 3B patients had a 28% PE rate (two fatal and three nonfatal) and an 11% PE-related death rate. None of the remaining patients in group 3 had a PE. CONCLUSIONS: Intraoperative IVC filter placement for the prevention of PE in morbidly obese patients undergoing OGB is feasible. We observed a significant reduction in the perioperative PE rate when a BMI greater than 55 kg/m2 was used as an indication for IVC filter placement despite the use of subcutaneous heparin injections and sequential compression devices

PURPOSE: To retrospectively assess endoleak shapes and locations within aneurysms to differentiate type II from type I and type III endoleaks. MATERIALS AND METHODS: The institutional review board granted an exemption for this HIPAA-compliant study; patient informed consent was not required. A retrospective review of arterial phase helical computed tomographic (CT) studies and medical records was performed for 39 patients (29 men, 10 women; age range, 60-89 years; mean, 78.5 years) who had an endoleak after endoaortic graft implantation for treatment of abdominal aortic aneurysm and who subsequently underwent angiography (n = 25), surgery (n = 8), or long-term follow-up (n = 6) to classify their endoleak into a specific type. At CT, endoleak shape (tubular or nontubular) and location (central or peripheral) were recorded. An endoleak was classified as type II if it contained a peripheral tubular component (PTC) near the aortic wall, with or without an identifiable feeding vessel. Endoleaks without these features were classified as type I or III. The Fisher exact test was used to assess associations between CT findings and endoleak type. RESULTS: There were 22 type II and 17 type I or III endoleaks. CT enabled correct identification of 22 (100%) of 22 type II endoleaks, all of which contained a PTC. Of 17 type I or III endoleaks, only two (12%) contained a PTC and were misclassified as type II endoleaks; the remaining 15 (88%) were correctly classified. Overall, CT enabled correct identification of endoleaks as type II or type I or III in 37 (95%) of 39 patients. PTCs were significantly more common (P < .001) in type II than in type I or III endoleaks, with a sensitivity, specificity, accuracy, negative predictive value, and positive predictive value of 100%, 88.2%, 94.9%, 100%, and 91.7%, respectively. CONCLUSION: A PTC is a statistically significant predictor of type II endoleak in most patients