Chromoendoscopy Is More Effective Than Standard Colonoscopy in Detecting Dysplasia During Long-term Surveillance of Patients With Colitis.

BACKGROUND & AIMS: Patients with colitis have an increased risk of colorectal cancer, compared with persons without colitis. Many studies have shown chromoendoscopy (CE) to be superior to standard methods of detecting dysplasia in patients with colitis at index examination. We performed a prospective, longitudinal study to compare standard colonoscopy vs CE in detecting dysplasia in patients with inflammatory bowel diseases in a surveillance program. METHODS: We analyzed data from 68 patients (44 men, 24 women) diagnosed with ulcerative colitis (n = 55) or Crohn's disease (n = 13) at Mount Sinai Medical Center from September 2005 through October 2011. The patients were followed from June 2006 through October 2011 (median, 27.8 months); each patient was analyzed by random biopsy, targeted white light examination (WLE), and CE. Specimens were reviewed by a single blinded pathologist. The 3 methods were compared by using the generalized estimating equations method, and the odds ratios (ORs) for detection of dysplasia were calculated (primary outcome). Time to colectomy was analyzed by using the Cox model. RESULTS: In the 208 examinations conducted, 44 dysplastic lesions were identified in 24 patients; 6 were detected by random biopsy, 11 by WLE, and 27 by CE. Ten patients were referred for colectomy, and no carcinomas were found. At any time during the study period, CE (OR, 5.4; 95% confidence interval [CI], 2.9-9.9) and targeted WLE (OR, 2.3; 95% CI, 1.0-5.3) were more likely than random biopsy analysis to detect dysplasia. CE was superior to WLE (OR, 2.4; 95% CI, 1.4-4.0). Patients identified as positive for dysplasia were more likely to need colectomy (hazard ratio, 12.1; 95% CI, 3.2-46.2). CONCLUSIONS: In a prospective study of 68 patients with inflammatory bowel diseases, CE was superior to random biopsy or WLE analyses in detecting dysplasia in patients with colitis during an almost 28-month period. A negative result from CE examination was the best indicator of a dysplasia-free outcome, whereas a positive result was associated with earlier referral for colectomy.

A simple tissue-handling technique performed in the endoscopy suite improves histologic section quality and diagnostic accuracy for serrated polyps.

BACKGROUND AND STUDY AIMS: Surveillance intervals after colonoscopic resection of serrated polyps are partially predicated on the histology of the polyp(s) removed during the index exam. Histologic discrimination between sessile serrated adenomas/polyps (SSA/P) and hyperplastic polyps is challenging. We devised and tested a simple tool--an envelope--that gastroenterologists can integrate into routine colonoscopy practice to address this problem. METHODS: In the "modified protocol," immediately after polypectomy each serrated polyp was flattened and enclosed in a paper envelope before being placed in formalin. In the pathology laboratory, each polyp was sectioned after processing. A two-site, prospective, randomized, single-blinded trial was performed to compare this modified protocol with the conventional protocol. Serrated polyps located proximal to the splenic flexure and 5-20 mm in diameter were included. A novel orientation score that measured the number of well-oriented crypts per unit area of polyp (higher orientation score = better orientation) was validated. Orientation score, SSA/P diagnosis rate, and inter-pathologist agreement were measured. RESULTS: A total of 375 polyps were enrolled, of which 264 were identified for analysis. The mean orientation scores in the modified and conventional protocol groups were 3.11 and 1.13, respectively (P < 0.0001). SSA/Ps were diagnosed in 103/135 cases (76.3%) in the modified protocol group vs. 54/129 (41.9%) in the conventional protocol group (P < 0.0001). Inter-pathologist agreement was higher with the modified than the conventional protocol (77.0% vs. 62.8%; P = 0.015). CONCLUSION: Standard polyp handling techniques may be sub-optimal for interpretation of serrated polyps resected at colonoscopy, and may lead to inadvertent histologic "under-grading" of many lesions. Our intervention improved histopathologic interpretation and increased the SSA/P diagnosis rate.

Localization of BRCA1 protein in breast cancer tissue and cell lines with mutations.

BACKGROUND: The breast and ovarian cancer susceptibility gene (BRCA1) encodes a tumor suppressor. The BRCA1 protein is found primarily in cell nuclei and plays an important role in the DNA damage response and transcriptional regulation. Deficiencies in DNA repair capabilities have been associated with higher histopathological grade and worse prognosis in breast cancer. METHODS: In order to investigate the subcellular distribution of BRCA1 in tumor tissue we randomly selected 22 breast carcinomas and tested BRCA1 protein localization in frozen and contiguous formalin-fixed, paraffin embedded (FFPE) tissue, using pressure cooker antigen-retrieval and the MS110 antibody staining. To assess the impact of BRCA1 germline mutations on protein localization, we retrospectively tested 16 of the tumor specimens to determine whether they contained the common Ashkenazi Jewish founder mutations in BRCA1 (185delAG, 5382insC), and BRCA2 (6174delT). We also compared co-localization of BRCA1 and nucleolin in MCF7 cells (wild type) and a mutant BRCA1 cell line, HCC1937 (5382insC). RESULTS: In FFPE tissue, with MS110 antibody staining, we frequently found reduced BRCA1 nuclear staining in breast tumor tissue compared to normal tissue, and less BRCA1 staining with higher histological grade in the tumors. However, in the frozen sections, BRCA1 antibody staining showed punctate, intra-nuclear granules in varying numbers of tumor, lactating, and normal cells. Two mutation carriers were identified and were confirmed by gene sequencing. We have also compared co-localization of BRCA1 and nucleolin in MCF7 cells (wild type) and a mutant BRCA1 cell line, HCC1937 (5382insC) and found altered sub-nuclear and nucleolar localization patterns consistent with a functional impact of the mutation on protein localization. CONCLUSIONS: The data presented here support a role for BRCA1 in the pathogenesis of sporadic and inherited breast cancers. The use of well-characterized reagents may lead to further insights into the function of BRCA1 and possibly the further development of targeted therapeutics.

Economic and safety implications of introducing fast tracking in congenital heart surgery.

BACKGROUND: The feasibility of fast-tracking children undergoing congenital heart disease surgery has not been assessed adequately. Current knowledge is based on limited single-center experiences without contemporaneous control groups. METHODS AND RESULTS: We compared administrative data for atrial septal defect (ASD) and ventricular septal defect (VSD) surgeries in children 2 months to 19 years of age at the Mount Sinai Medical Center (MSMC) with data from comparable patients at 40 centers contributing to the Pediatric Health Information System. Three-year blocks, early in and after fast tracking had been implemented at the MSMC, were examined. Seventy-seven and 89 children at MSMC undergoing ASD and VSD closure, respectively, were compared with 3103 ASD and 4180 VSD patients nationally. With fast tracking fully implemented, median length of stay at the MSMC decreased by 1 day compared with the earlier era (length of stay, 1 and 3 days for ASD and VSD, respectively). Nationally, median length of stay remained unchanged (3 days for ASD and 4 days for VSD) in the observed time periods. Hospitalization costs fell by 33% and 35% at MSMC (ASD and VSD, respectively), whereas they rose by 16% to 17% nationally. When analyzed in multiple regression models, the decrease in both length of stay and cost remained significantly greater at MSMC compared with nationally (P<0.0001 for all). Hospital mortality and 2-week readmission rates were unchanged at MSMC between the 2 time periods and were not different from the national rates. CONCLUSION: Shorter length of stay and cost savings compared with national data were observed after implementation of fast tracking.

Vocal cord paralysis after aortic surgery.

OBJECTIVE: The purpose of this study was to investigate variables associated with vocal cord paralysis during complex aortic procedures. DESIGN: A retrospective review. SETTING: A tertiary care center. PARTICIPANTS: Four hundred ninety-eight patients who underwent aortic surgery between 2002 and 2007. METHODS: Two groups were studied. Group A patients had procedures only involving their aortic root and/or ascending aorta. Group B patients had procedures only involving their aortic arch and/or descending aorta. RESULTS: The incidence of vocal cord paralysis was higher (7.26% v 0.8%) in group B patients (p < 0.0001). Increasing the duration of cardiopulmonary bypass time was associated with an increased risk of vocal cord paralysis and death in both groups A and B (p = 0.0002 and 0.002, respectively). Additionally, within group B, descending aneurysms emerged as an independent risk factor associated with vocal cord paralysis (p = 0.03). Length of stay was statistically significantly longer among group A patients who suffered vocal cord paralysis (p = 0.017) and trended toward significance in group B patients who suffered vocal cord paralysis (p = 0.059). The association between tracheostomy and vocal cord paralysis among group A patients reached statistical significance (p = 0.007) and trended toward significance in group B patients (p = 0.057). CONCLUSIONS: Increasing duration of cardiopulmonary bypass time was associated with a higher risk of vocal cord paralysis in patients undergoing aortic surgery. Additionally, within group B patients, descending aortic aneurysm was an independent risk factor associated with vocal cord paralysis. Most importantly, vocal cord paralysis appeared to have an association between an increased length of stay and tracheostomy among a select group of patients undergoing aortic surgery.

Early extubation in adults undergoing surgery for congenital heart disease.

OBJECTIVES: Early extubation in adults undergoing surgery for congenital heart disease has not been described. The authors report their experience with extubation in the operating room (OR), including factors associated with the decision to defer extubation to a later time. DESIGN: A retrospective chart review. SETTING: A tertiary-care teaching hospital. PARTICIPANTS: This study included adults undergoing surgery for congenital heart disease using cardiopulmonary bypass. Exclusion criteria were as follows: preoperative mechanical ventilation, age >70 years, inotrope score >20 after surgery, and surgical risk (Risk Adjustment for Congenital Heart Surgery [RACHS] score ≥4). INTERVENTIONS: A stepwise logistic regression model was used to test for the independent influence of the various factors on extubation in the OR. MEASUREMENTS AND MAIN RESULTS: Sixty-seven patients (age 18-59 years, median = 32 years) were included. Overall, 79% of patients were extubated in the OR. The RACHS score was the strongest predictor of deferring extubation (RACHS 3 v 1 or 2: odds ratio = 16.7; 95% confidence interval, 3.3-84.2; p = 0.0006). Further exploration of the high-risk group (RACHS 3) showed that 75% of the RACHS 3 patients with a body mass index <25 were extubated compared with only 20% of patients who had a body mass index ≥25 (p = 0.01). Other factors included in the analysis did not contribute any additional independent information. CONCLUSIONS: Extubation of adult patients in the OR after surgery for congenital heart disease is feasible in most cases. Surgical risk (RACHS score) and body mass index predict the decision for OR extubation in this patient population.

Is production pressure jeopardizing the quality of colonoscopy? A survey of U.S. endoscopists' practices and perceptions.

BACKGROUND: Fatigue is an underestimated cause of underperformance among physicians. There is evidence that fatigue or other byproducts of production pressure may negatively influence the quality of colonoscopy. OBJECTIVE: To investigate the practices and perceptions of U.S. endoscopists regarding the effect of production pressure on the performance of colonoscopy. DESIGN: We conducted a 40-question online survey to assess endoscopists' practices and perceptions concerning production pressure. SETTING: A total of 5030 U.S. American Society for Gastrointestinal Endoscopy members. MAIN OUTCOME MEASUREMENTS: The proportion of endoscopists responding positively to questions pertaining to the impact of production pressure on colonoscopy practice. RESULTS: Ninety-two percent of respondents indicated that production pressure influenced one or more aspects of their endoscopic practices. Examples of production pressure included (1) postponing polypectomy for a subsequent session (2.8%), (2) reducing the length of time spent inspecting the colon (7.2%), and (3) proceeding with colonoscopy in a patient with an unfavorable risk/benefit ratio (69.2%). Forty-eight percent of respondents reported witnessing the effects of production pressure on a colleague. Respondents working fee-for-service and those with >10 years since completion of fellowship were more likely to describe their weekly workloads as excessive compared with those who were salaried (81.3% vs 71.3%; P = .01) and <10 years out of training (81% vs 72.7%; P = .01). LIMITATIONS: Nonresponse bias due to low response rate (22.3%). CONCLUSION: Production pressure influences the conduct of colonoscopy for many endoscopists and could have an adverse effect on the outcome of colorectal cancer screening. ( CLINICAL TRIAL REGISTRATION NUMBER: RE:GIE D 11-01288R1.) The study was an Internet study and did not involve human subjects.

Preoperative arterial pulse pressure has no apparent association with perioperative mortality after lower extremity arterial bypass.

BACKGROUND: Arterial pulse pressure hypertension is associated with perioperative morbidity and mortality in cardiac surgery patients. However, its association with perioperative mortality in other high-risk surgical populations has not been determined. In this study, we tested the hypothesis that increased preoperative arterial pulse pressure is associated with 30-day and 1-year all-cause mortality after lower extremity arterial bypass surgery. METHODS: A retrospective review of patients who had infrainguinal arterial bypass surgery at a single center over a 6-year period (January 2002 to January 2008) was performed (n = 556). Mean, systolic, and diastolic arterial blood pressure were determined from a single noninvasive oscillometric blood pressure cuff reading in the operating room before the administration of anesthetic drugs. Pulse pressure was calculated from this measurement in a retrospective manner by subtracting diastolic pressure from systolic pressure. Mortality for all subjects was determined using the social security death index. Comorbid conditions, preoperative medications, and anesthetic techniques were recorded. Univariate and multivariate analyses were performed to evaluate the association between arterial pulse pressure and the primary outcome variables, and all-cause 30-day and 1-year mortality. RESULTS: Of the 556 patients, a large percentage had elevated pulse pressure (44.9% had pulse pressure ≥80). Thirty-day mortality was 5.1% and 1-year mortality was 17.8%. There was no apparent association between preoperative pulse pressure and 30-day (P = 0.35) or 1-year (P = 0.14) all-cause mortality. Independent predictors of 30-day mortality were age ≥80 years (P = 0.02), ASA physical status ≥IV (P = 0.04), baseline creatinine >2.0 mg/dL (P < 0.0001), and emergency surgery (P = 0.009). The same variables were associated with 1-year mortality, as were the Lee's Revised Cardiac Risk Index score, female gender, and gangrene or ulcer as an indication for surgery. CONCLUSION: Our results suggest that increased preoperative arterial pulse pressure might not be associated with all-cause mortality after lower extremity arterial bypass surgery.

A morphologic analysis of sessile serrated polyps observed during routine colonoscopy (with video).

BACKGROUND: Proximal colorectal cancer may arise from sessile serrated polyps (SSPs), which are often inconspicuous during colonoscopy. The gross morphologic characteristics of SSPs have not been systematically described, and this omission may contribute to colonoscopists overlooking them. OBJECTIVES: To analyze the gross morphologic characteristics of SSPs detected during routine colonoscopy. DESIGN: Retrospective analysis of high-resolution endoscopic video clips depicting SSPs in situ. SETTING: Outpatient gastroenterology practice. PATIENTS: A total of 124 subjects undergoing surveillance or screening colonoscopy after split-dose bowel preparation. INTERVENTIONS: Analysis of 158 SSPs performed by using validated descriptors. MAIN OUTCOME MEASUREMENTS: The prevalence of morphologic characteristics related to polyp shape, color, and texture. RESULTS: A total of 158 SSPs were studied. For 7 visual descriptors, a κ coefficient of ≥ 0.7 was achieved, indicating good to excellent intraobserver agreement. The most prevalent visual descriptors were the presence of a mucous cap (63.9%), rim of debris or bubbles (51.9%), alteration of the contour of a fold (37.3%), and interruption of the underlying mucosal vascular pattern (32.3%). The most common "sentinel signs" were the presence of a mucous cap and alteration of the contour of a mucosal fold (each 24.6%), rim of debris or bubbles (21.7%), and a dome-shaped protuberance (20.3%). When comparing SSPs with adenomatous polyps, the frequencies of 5 of 7 morphologic characteristics and the distribution of sentinel signs differed (P < .01). LIMITATIONS: Single-site, retrospective analysis. CONCLUSIONS: SSPs exhibit distinct, variable morphologic characteristics. Many do not display classic features such as a mucous cap. Enhanced appreciation of these morphologic characteristics may improve SSP detection and thereby colorectal cancer prevention.

Indication for surgery, the revised cardiac risk index, and 1-year mortality.

BACKGROUND: Patients who undergo vascular surgery are at increased risk of perioperative cardiovascular morbidity and mortality. The Revised Cardiac Risk Index (RCRI) is a validated and widely used bedside tool for estimating the risk of a perioperative major adverse myocardial event. We hypothesized that inclusion of the indication for surgery would add independent and prognostic information to the RCRI in predicting all-cause 30-day and 1-year mortality in open infrainguinal vascular surgical procedures. METHODS: This was a retrospective study of 603 patients who underwent open infrainguinal bypass vascular surgery between January 2002 and January 2008 at a tertiary care medical center. RCRI and indication for surgery were determined. The primary outcomes of interest were all-cause 30-day mortality (which included all in-hospital mortality, regardless of time) and all-cause 1-year mortality. RESULTS: Overall 30-day mortality was 32 (5.3%). Independent risk factors for early death were RCRI score, being of age ≥80 years, American Society of Anesthesiologists Physical Status classification = 4, and emergency surgery. Overall 1-year mortality, including early deaths, was 114 (18.9%). Indication for surgery, RCRI score, age, American Society of Anesthesiologists Physical Status classification = 4, female sex, and emergency surgery were all independent predictors of 1-year mortality. CONCLUSIONS: The RCRI score was associated with both 30-day and 1-year mortality in patients undergoing lower extremity bypass surgery. Indication for surgery was predictive of 1-year mortality but not of 30-day mortality.

Staged approach prevents spinal cord injury in hybrid surgical-endovascular thoracoabdominal aortic aneurysm repair: an experimental model.

BACKGROUND: In a porcine model, we investigated the impact of sudden stent graft occlusion of thoracic intercostal arteries after open lumbar segmental artery (SA) ligation. METHODS: After randomization into two groups, 20 juvenile Yorkshire pigs (27.1±0.6 kg) underwent open lumbar SA sacrifice (T13-L5) followed by endovascular coverage of all thoracic SAs (T4-T12) at 32°C, either in a single operation (group 1) or in two stages separated by seven days (group 2). Collateral network pressure (CNP) was monitored by catheterization of the SA L1, and postoperative hind limb function was assessed using a modified Tarlov score. RESULTS: The CNP in group 1 decreased to 34% of baseline, whereas CNP after lumbar SA ligation in group 2 fell to 55% of baseline (74±2.4 to 25±3.6 mm Hg vs 74±4.5 to 41±5.5 mm Hg; p<0.0001). Subsequent thoracic stenting (group 2) led to another significant but milder drop (p=0.002 versus stage 1) from the restored CNP (71±4.2 to 54±4.9 mm Hg). Five of ten pigs in group 1 suffered paraplegia, in contrast to none in group 2 (median Tarlov score 6, vs 9; p=0.0031). Histopathologic analysis showed more severe ischemic damage to the lower thoracic (p=0.05) and lumbar spinal cord (p=0.002) in group 1. CONCLUSIONS: These results underline the potential of the staged approach in hybrid procedures. Furthermore they highlight the need for established adjuncts for preventing paraplegia in hybrid and pure stent-graft protocols in which sudden occlusion of multiple SAs occurs.

Factors affecting the decision to defer endotracheal extubation after surgery for congenital heart disease: a prospective observational study.

BACKGROUND: Fast-tracking and early endotracheal extubation have been described in patients undergoing surgery for congenital heart disease (CHD); however, criteria for patient selection have not been validated in a prospective manner. Our goal in this study was to prospectively identify factors associated with the decision to defer endotracheal extubation in the operating room (OR). METHODS: We performed a prospective observational study of 275 patients (median age 18 months) at the Mount Sinai Medical Center (MSMC), New York, New York, and 49 patients (median age 25 months) at the University of Tokyo Hospital (UTH), Tokyo, Japan, undergoing surgery for CHD requiring cardiopulmonary bypass. These patients were all eligible for fast-tracking, including extubation in the OR immediately after surgery, according to the respective inclusion/exclusion criteria applied at the 2 sites. RESULTS: Eighty-nine percent of patients at the MSMC, and 65% of patients at the UTH were extubated in the OR. At the MSMC, all patients without aortic cross-clamp, and patients with simple procedures (Risk Adjustment for Congenital Heart Surgery [RACHS] score 1) were extubated in the OR. Among the remaining MSMC patients, regression analysis showed that procedure complexity was still an independent predictor for not proceeding with planned extubation in the OR. Extubation was more likely to be deferred in the RACHS score 3 surgical risk patients compared with the RACHS score 2 group (P = 0.005, odds ratio 3.8 [CI: 1.5, 9.7]). Additionally, trisomy 21 (P = 0.0003, odds ratio 9.9 [CI: 2.9, 34.5]) and age (P = 0.0015) were significant independent predictors for deferring OR extubation. We tested our findings on the patients from the UTH by developing risk categories from the MSMC data that ranked eligible patients according to the chance of OR extubation. The risk categories proved to predict endotracheal extubation in the 49 patients who had undergone surgery at the UTH relative to their overall extubation rate, despite differences in anesthetic regimen and inclusion/exclusion criteria. CONCLUSIONS: Preoperatively known factors alone can predict the relative chances of deferring extubation after surgery for CHD. The early extubation strategies applied in the 2 centers were successful in the majority of cases.

The detection of premalignant colon polyps during colonoscopy is stable throughout the workday.

BACKGROUND: Recent studies have shown that colonoscopic polyp detection decreases as the workday progresses. This may reflect time-dependent factors such as colonoscopist fatigue and decreased colon cleanliness, which can be addressed through adaptations in colonoscopy practice. OBJECTIVE: To test for time-of-day differences in adenomatous polyp (AP) and sessile serrated polyp (SSP) detection in a practice that uses split-dose bowel preparation and moderated daily colonoscopist procedure loads. DESIGN: Retrospective chart review. SETTING: Community-based, group gastroenterology practice. PATIENTS: This study involved 2439 patients undergoing surveillance or screening colonoscopy. INTERVENTION: Colonoscopy. MAIN OUTCOME MEASUREMENTS: Detection rate of all premalignant polyps (PMPs), and of APs and SSPs, individually. RESULTS: A total of 1183 PMPs were identified in 1486 eligible patients (mean PMP/colonoscopy = 0.80; PMP detection rate = 47%). In univariate and multivariate analyses, PMP detection as well as detection of APs or SSPs individually did not vary significantly in relation to the hour of the day. In a binary comparison of morning (am) versus afternoon (pm) procedures, the total polyp detection rate was 67% and 66%, respectively. For PMPs, APs, SSPs, and hyperplastic polyps (HPs), the am and pm detection rates were 46% and 47%, 41% and 44%, 8% and 8%, and 27% and 24%, respectively. Bowel preparation quality was independent of time of day and was rated excellent or good in 86% to 87% of cases. LIMITATIONS: Retrospective, nonrandomized study. CONCLUSION: Stable PMP, AP, SSP, and HP detection rates throughout the workday occur under certain practice conditions, including the use of split-dose bowel preparation and/or moderated daily colonoscopist procedure loads.

Is gastroduodenal biopsy safe in patients receiving aspirin and clopidogrel?: a prospective, randomized study involving 630 biopsies.

GOALS: To assess prospectively the bleeding risk attributable to gastroduodenal biopsy in subjects taking antiplatelet medications. BACKGROUND: No prospective data exist regarding the bleeding risk attributable to endoscopic biopsy in patients taking antiplatelet agents. A majority of Western endoscopists withdraw antiplatelet agents before upper endoscopy, despite expert guidelines to the contrary. STUDY: We performed a prospective, single-blind, randomized study in healthy volunteers participating in a larger study regarding the effect of antiplatelet agents on gastroduodenal mucosal healing. Multiple gastroduodenal biopsies were performed during 2 esophagogastroduodenoscopy in subjects dosed with aspirin enteric-coated 81 mg once daily or clopidogrel 75 mg once daily. Data for endoscopic bleeding, clinical bleeding, blood vessel size, and depth of biopsy in histology specimens were collected. RESULTS: Four hundred and five antral biopsies and 225 duodenal biopsies were performed during 90 esophagogastroduodenoscopy in 45 subjects receiving aspirin or clopidogrel. Median maximum blood vessel diameter per biopsy was 31.9 µ (range: 9.2 to 133.8). About 50.8% of biopsy specimens breached the muscularis mucosa. In the clopidogrel group, no bleeding events were noted after 350 biopsies [upper confidence limit (UCL) for probability of bleeding=0.0085]. In the aspirin group, there were no clinical events (UCL=0.0106) and one minor endoscopic bleeding event (UCL=0.0169). CONCLUSIONS: Consistent with expert guidelines, the absolute risk attributable to gastroduodenal biopsy in adults taking antiplatelet agents seems to be low. Half of routine biopsies enter submucosa. The largest blood vessels avulsed during biopsy correspond to midsized and large arterioles and venules.

The influence of simulation-based physiology labs taught by anesthesiologists on the attitudes of first-year medical students towards anesthesiology.

BACKGROUND: The development of medical students' perceptions of different medical specialties is based on many factors and influences their career choices and appreciation of other practitioners' knowledge and skills. The goal of this study was to determine if participation in a series of anesthesiologist-run, simulation-based physiology labs changed first year medical students' perceptions of anesthesiologists. METHODS: One hundred first-year medical students were surveyed at random three months before completion of a simulation-based physiology lab run by anesthesiologists. All participants received the same survey instrument, which employed a 5-point Rating Scale to rate the appropriateness of several descriptive terms as they apply to a particular specialist or specialty. A post-simulation survey was performed to track changes in attitudes. RESULTS: Response rates to the survey before and after the simulation labs were 75% and 97% (ofthe initial cohort responding), respectively. All students who filled out the post-simulation surveys had been exposed to anesthesiologists in the prior three months whereas none had interacted with surgeons in the interim. Nearly all had interacted with internal medicine specialists in that time period. No changes in the medical students' perceptions of surgeons or internal medicine specialists were evident. Statistically significant changes were found for most descriptors of anesthesiologists, with a trend towards a more favorable perception after the simulation program. CONCLUSIONS: Using a survey instrument containing descriptors of different medical specialists and specialties, we found an improved attitude towards anesthesiology after medical students participated in an anesthesiologist-run simulation-based physiology lab series. Given the importance of providing high quality medical education and attracting quality applicants to the field, integrati-on of anesthesiology staff into medical student courses at the non-clinical level appears useful.

Measuring the collateral network pressure to minimize paraplegia risk in thoracoabdominal aneurysm resection.

OBJECTIVE: To minimize paraplegia during thoracoabdominal aortic aneurysm repair, the concept of the collateral network was developed. That is, spinal cord perfusion is provided by an interconnecting complex of vessels in the intraspinal, paraspinous, and epidural space and in the paravertebral muscles, including intercostal and lumbar segmental as well as subclavian and hypogastric arteries. METHODS: Collateral network pressure was measured with a catheter in the distal end of a ligated segmental artery in pigs and human beings. RESULTS: In the pig, collateral network pressure was 75% of the simultaneous mean aortic pressure. With complete segmental arterial ligation, it fell to 27% of baseline, recovering to 40% at 24 hours and 90% at 120 hours. Spinal cord injury occurred in approximately 50% of animals. When all segmental arteries were taken in 2 stages a week apart, collateral network pressure fell only to 50% to 70% of baseline, and spinal cord injury was rare. In human beings, baseline collateral network pressure also was 75% of mean aortic pressure, fell in proportion to the number of segmental arteries ligated, and began recovery within 24 hours. Collateral network pressure was lower with nonpulsatile distal bypass than with pulsatile perfusion. CONCLUSIONS: After subtraction of a measure of spinal cord outflow pressure (cerebrospinal fluid pressure or central venous pressure), collateral network pressure provides a clinically useful estimate of spinal cord perfusion pressure.

The Bentall procedure: is it the gold standard? A series of 597 consecutive cases.

OBJECTIVES: We compared aortic root reconstructions using conduits with biological valves and mechanical valves. METHODS: Of 597 patients (1995-2008), 307 (mean age 71 years [23-89 years]) had biological valves and 290 (mean age 51 years [21-82 years]) had mechanical valves. The subgroup of 242 patients aged 50 to 70 years included 133 with biological and 109 with mechanical valves. RESULTS: Overall hospital mortality was 3.9% with biological valves (n = 15; elective: 3.7% [n = 10]) versus 2.8% with mechanical valves (n = 8; elective: 1.4% [n = 3]). In patients 50 to 70 years, age greater than 65 years (relative risk: 3.3 [P = .0001]), clot (relative risk: 2.5 [P = .05]), coronary artery disease (relative risk:3.5 [P < .0001]), and degenerative etiology (relative risk: 0.4 [P = .006]) were independent risk factors for long-term survival (after postoperative day 30); there was no difference in long-term survival between biological and mechanical valves (relative risk: 0.9 [P = .74]). The linearized rate for valve/ascending aorta reoperation was 0.86%/pt-y (2 in 2310 pt-y) after mechanical valves and 2.5%/pt-y (4 in 1586 pt-y) after Bentall procedures with the biological valve. CONCLUSIONS: The choice of valve for aortic root reconstruction seems to have no influence on long-term outcome. Emergency operation and the presence of clot/atheroma have a significant impact on short-term outcome. Reoperation for either ascending aorta and/or aortic valve is low.

Long-term outcome after aortic arch replacement with a trifurcated graft.

OBJECTIVE: We describe the long-term results of aortic arch replacement using a trifurcated graft, including an assessment of survival, neurologic complications, and graft patency. METHODS: A retrospective review was conducted on data from 206 consecutive patients (125 male; median age, 67 years; range, 20-87 years) who had a trifurcated graft used for aortic arch replacement between September 1999 and September 2009. Seventy-four patients (35.9%) had chronic dissection, 68 patients (33.0%) had atherosclerotic aneurysms, and 39 patients (18.9%) had degenerative disease. Ninety-one patients (44.2%) had undergone previous cardiac surgery. RESULTS: An elephant trunk was placed in 190 patients (92.2%) and completed in 101 patients (53.1%), with an interval of less than 365 days between stages in 94 of 101 patients. Hospital mortality was 6.8% (14/206). Adverse outcome (death/stroke within the first year postoperatively) occurred in 27.7% of patients (57/206; 50 deaths/7 strokes). Among 152 1-year survivors, the annual rates of transient ischemic attack and stroke were 0.85% and 1.1%, respectively. At 6 years, 75% of patients were still alive, compared with 92% in a matched New York State control population (P < .001). Follow-up computed tomography scans (189 studies in 176/206 patients [85.4%]) revealed 100% patency of the trifurcated graft limbs at a mean of 2.3 years. CONCLUSIONS: Aortic arch replacement using a trifurcated graft is highly durable, with excellent patency in the branch grafts, and is associated with a low incidence of cerebral embolization. However, the long-term outcome in these patients is compromised by extensive comorbidities.

When to operate on the bicuspid valve patient with a modestly dilated ascending aorta.

BACKGROUND: Bicuspid aortic valves (BAV) are frequently associated with root/ascending aorta dilatation, but there is controversy regarding when to operate to prevent dissection of a dilated aorta associated with a well-functioning BAV. METHODS: From 1988 through 2008, 158 patients (mean age: 56 ± 13.5 years) with a dilated ascending aorta (AA) and a well-functioning BAV were referred to our institution. All patients underwent computed tomographic (CT) scanning and digitization to calculate mean AA diameter. Forty-two patients underwent operation a median of 52 days after initial CT scan with a mean AA diameter of 5.6 ± 0.5 cm. One hundred sixteen patients (mean diameter 4.6 ± 0.5 cm) were enrolled in annual or semiannual surveillance. Seventy-one patients, 45 with 2 or more CT scans, are still under surveillance. RESULTS: Average follow-up was 6.5 ± 4.1 years. Overall survival after the first encounter was 93% at 5 years and 85% at 10 years. A total of 87 of 158 patients had a Bentall or Yacoub procedure, with two hospital deaths (2.3%). Mean duration of surveillance in the 116 patients without immediate operation was 4.2 ± 2.9 years (481 patient-years). Average growth rate of the AA in patients with 2 scans or greater was 0.77 mm/year (p < 0.0001 versus normal population) with no significant impact of hypertension, sex, smoking or age. Forty-five of the 116 surveillance patients underwent operation after a mean of 3.4 ± 2.9 years (mean age 55 ± 14.7 years; mean AA diameter 4.9 ± 0.6 cm). Six patients died without surgery, median age 82 (range, 44 to 87) years, but none within one year of the last CT scan. CONCLUSIONS: A consistent approach to patients with a well-functioning BAV and AA dilatation, recommending operation to those with an AA diameter greater than 5 cm and deferring operation in patients under surveillance in the absence of significant enlargement (>0.5 cm/year), resulted in overall survival equivalent to a normal age-matched and sex-matched population. Operation was necessary in approximately 10% of patients under surveillance each year.

The efficacy of post-cardiopulmonary bypass dosing of vancomycin in cardiac surgery.

Objective. Vancomycin is administered widely to patients undergoing cardiac surgery as prophylaxis against resistant Gram-positive sternal wound and venous donor site infections. The purpose of this study was to determine the efficacy of a standardized prebypass and postbypass dosing regimen of vancomycin by assessing plasma concentrations in the immediate postoperative period and postoperative surgical site infections (SSIs). Design. Retrospective cohort study. Setting . Cardiothoracic surgical intensive care unit in a tertiary care academic medical center. Methods. A total of 34 consecutive adult patients who had undergone cardiac surgery with cardiopulmonary bypass (CPB) were analyzed retrospectively. Each patient received 1000 mg of vancomycin administered over 1 hour around the time of induction of anesthesia and 500 mg after discontinuation of CPB. Trough vancomycin levels were sampled in the intensive care unit 12 hours after the last dose given in the operating room. Along with patient characteristics, postoperative readmission rates and SSIs were recorded for 1 year after surgery. Results. The nadir serum vancomycin level before the next dose was 9.3 ± 4.5 µg/mL (mean ± standard deviation). One superficial SSI was noted. Readmission rate for SSIs was 2.94%. Conclusion . Vancomycin concentrations in the serum were greater than the minimum inhibitory concentration for most staphylococci ranging from 4 to 19.3 µg/mL producing acceptable therapeutic serum concentrations and low rate of infectious complications. Thus postbypass dosing is acceptable in vancomycin cardiac surgical prophylaxis.