Endovascular aneurysm repair simulation can lead to decreased fluoroscopy time and accurately delineate the proximal seal zone.

BACKGROUND: The use of simulators for endovascular aneurysm repair (EVAR) is not widespread. We examined whether simulation could improve procedural variables, including operative time and optimizing proximal seal. For the latter, we compared suprarenal vs infrarenal fixation endografts, right femoral vs left femoral main body access, and increasing angulation of the proximal aortic neck. METHODS: Computed tomography angiography was obtained from 18 patients who underwent EVAR at a single institution. Patient cases were uploaded to the ANGIO Mentor endovascular simulator (Simbionix, Cleveland, Ohio) allowing for three-dimensional reconstruction and adapted for simulation with suprarenal fixation (Endurant II; Medtronic Inc, Minneapolis, Minn) and infrarenal fixation (C3; W. L. Gore & Associates Inc, Newark, Del) deployment systems. Three EVAR novices and three experienced surgeons performed 18 cases from each side with each device in randomized order (n = 72 simulations/participant). The cases were stratified into three groups according to the degree of infrarenal angulation: 0° to 20°, 21° to 40°, and 41° to 66°. Statistical analysis used paired t-test and one-way analysis of variance. RESULTS: Mean fluoroscopy time for participants decreased by 48.6% (P < .0001), and total procedure time decreased by 33.8% (P < .0001) when initial cases were compared with final cases. When stent deployment accuracy was evaluated across all cases, seal zone coverage in highly angulated aortic necks was significantly decreased. The infrarenal device resulted in mean aortic neck zone coverage of 91.9%, 89.4%, and 75.4% (P < .0001 by one-way analysis of variance), whereas the suprarenal device yielded 92.9%, 88.7%, and 71.5% (P < .0001) for the 0° to 20°, 21° to 40°, and 41° to 66° cases, respectively. Suprarenal fixation did not increase seal zone coverage. The side of femoral access for the main body did not influence proximal seal zone coverage regardless of infrarenal angulation. CONCLUSIONS: Simulation of EVAR leads to decreased fluoroscopy times for novice and experienced operators. Side of femoral access did not affect precision of proximal endograft landing. The angulated aortic neck leads to decreased proximal seal zone coverage regardless of infrarenal or suprarenal fixation devices.

Prevalence of Bovine Aortic Arch Configuration in Adult Patients with and without Thoracic Aortic Pathology.

BACKGROUND: Bovine aortic arch (BA) occurs in approximately 15-35% of the US population and is regarded as a clinically insignificant, normal variant. The aim of this study was to assess the prevalence of types I (type I bovine arch [T1BA], common origin of innominate and/or left common carotid artery) and II (type II bovine arch [T2BA], left common carotid originating from innominate) bovine arch in patients with and without thoracic aortic pathology. METHODS: We retrospectively reviewed all serial computed tomography images (n = 817) performed at our institution over 4 months to determine the overall prevalence of BA. Thoracic aorta and/or arch vessels were visualized, with images read by certified radiologists. A separate analysis compared a series of 156 consecutive patients with thoracic pathology (dissection or aneurysm ≥ 4.0 cm), from a 25-month period, with 757 control patients without pathology from the original sample. Statistical analysis included a chi-squared contingency table. RESULTS: Analysis revealed a bovine arch prevalence of 31.1% (n = 254), including 14.9% T1BA and 16.2% T2BA. Patients with thoracic aortopathy (n = 156) had aortic dissection (n = 26) or aneurysm (n = 130). These patients were older and had an increased prevalence of hypertension, hyperlipidemia, and aortic calcification. In addition, there was increased prevalence of T2BA in the pathology group (23.7%) compared with controls (15.9%; P = 0.03). T1BA was not significantly different between groups (11.5% vs. 14.9%; P = 0.59). When thoracic disease was stratified by pathology type, T2BA occurred more frequently in patients with thoracic aortic aneurysm (24.6% vs. 15.9%; P = 0.04). BA trended upward, in patients with thoracic aortic dissection (42.3% vs. 30.8%; P = 0.28). CONCLUSIONS: Our analyses revealed a prevalence of bovine arch of 31% in our patient population. BA occurred more frequently in patients with thoracic aortopathy than controls. Therefore, patients with BA may be associated with higher levels of thoracic aortic pathology and may benefit from increased clinical vigilance.

Comparative occupational radiation exposure between fixed and mobile imaging systems.

OBJECTIVE: Endovascular intervention exposes surgical staff to scattered radiation, which varies according to procedure and imaging equipment. The purpose of this study was to determine differences in occupational exposure between procedures performed with fixed imaging (FI) in an endovascular suite compared with conventional mobile imaging (MI) in a standard operating room. METHODS: A series of 116 endovascular cases were performed over a 4-month interval in a dedicated endovascular suite with FI and conventional operating room with MI. All cases were performed at a single institution and radiation dose was recorded using real-time dosimetry badges from Unfors RaySafe (Hopkinton, Mass). A dosimeter was mounted in each room to establish a radiation baseline. Staff dose was recorded using individual badges worn on the torso lead. Total mean air kerma (Kar; mGy, patient dose) and mean case dose (mSv, scattered radiation) were compared between rooms and across all staff positions for cases of varying complexity. Statistical analyses for all continuous variables were performed using t test and analysis of variance where appropriate. RESULTS: A total of 43 cases with MI and 73 cases with FI were performed by four vascular surgeons. Total mean Kar, and case dose were significantly higher with FI compared with MI. (mean ± standard error of the mean, 523 ± 49 mGy vs 98 ± 19 mGy; P < .00001; 0.77 ± 0.03 mSv vs 0.16 ± 0.08 mSv, P < .00001). Exposure for the primary surgeon and assistant was significantly higher with FI compared with MI. Mean exposure for all cases using either imaging modality, was significantly higher for the primary surgeon and assistant than for support staff (ie, nurse, radiology technologist) beyond 6 feet from the X-ray source, indicated according to one-way analysis of variance (MI: P < .00001; FI: P < .00001). Support staff exposure was negligible and did not differ between FI and MI. Room dose stratified according to case complexity (Kar) showed statistically significantly higher scattered radiation in FI vs MI across all quartiles. CONCLUSIONS: The scattered radiation is several-fold higher with FI than MI across all levels of case complexity. Radiation exposure decreases with distance from the radiation source, and is negligible outside of a 6-foot radius. Modern endovascular suites allow high-fidelity imaging, yet additional strategies to minimize exposure and occupational risk are needed.

Representativeness of enrollment into a perinatal research repository.

OBJECTIVE: To describe enrollment and compare demographic and clinical characteristics of neonates enrolled in the perinatal research repository (PRR) with eligible, but non-enrolled neonates. METHODS: Characteristics from enrolled infants were compared with eligible, but non-enrolled infants using t-tests, Wilcoxon rank tests and χ(2) tests. RESULTS: Between 1 January 2010 and 31 December 2011, 622 infants admitted to the neonatal intensive care unit (NICU), born < 37 weeks were screened for the PRR were eligible for enrollment. Of these, 233 enrolled in the study. There were no significant differences between enrolled and non-enrolled infants with regard to race, birth weight, gestational age and Apgar scores. Enrolled patients had a significantly longer length of stay [mean (standard deviation) = 55.0 (58.9) versus 38.0 (45.8) days; p < 0.01]. Mortality was significantly greater in the non-enrolled group (11.7 versus 3.0%; p < 0.01). Both groups had a similar total number of diagnoses [mean (standard deviation) = 5.7 (3.1) versus 5.8 (3.2)]; however, among survivors enrolled infants had slightly lower prevalence of hypoxic ischemic encephalopathy (0.0 versus 2.9%; p < 0.01) and seizures (1.8 versus 6.4%; p < 0.01). There were no significant differences in enrollment by prevalence of other morbidities. CONCLUSIONS: These results suggest that a specimen collecting repository can enroll a sufficiently representative sample of eligible patients.

Cancer in pregnancy: fetal and neonatal outcomes.

Cancer during pregnancy represents a potential conflict between optimal maternal treatment and fetal development. Traditionally, clinicians operated under the assumption that cancer treatment during pregnancy is incompatible with normal fetal development. However, recent evidence suggests that many diagnostic and treatment modalities cause little or no harm to the developing fetus. As such, both maternal and neonatal interests should be considered when developing management strategies for pregnant cancer patients. In this review, we will discuss issues related to fetal and neonatal health associated with conventional diagnostic and treatment approaches in the care of pregnant women with cancer. In addition, we offer recommendations on strategies to maximize fetal outcomes in pregnancies complicated by cancer.

Fellows as teachers: a model to enhance pediatric resident education.

OBJECTIVE: Pressures on academic faculty to perform beyond their role as educators has stimulated interest in complementary approaches in resident medical education. While fellows are often believed to detract from resident learning and experience, we describe our preliminary investigations utilizing clinical fellows as a positive force in pediatric resident education. Our objectives were to implement a practical approach to engage fellows in resident education, evaluate the impact of a fellow-led education program on pediatric resident and fellow experience, and investigate if growth of a fellowship program detracts from resident procedural experience. METHODS: This study was conducted in a neonatal intensive care unit (NICU) where fellows designed and implemented an education program consisting of daily didactic teaching sessions before morning clinical rounds. The impact of a fellow-led education program on resident satisfaction with their NICU experience was assessed via anonymous student evaluations. The potential value of the program for participating fellows was also evaluated using an anonymous survey. RESULTS: The online evaluation was completed by 105 residents. Scores were markedly higher after the program was implemented in areas of teaching excellence (4.44 out of 5 versus 4.67, p<0.05) and overall resident learning (3.60 out of 5 versus 4.61, p<0.001). Fellows rated the acquisition of teaching skills and enhanced knowledge of neonatal pathophysiology as the most valuable aspects of their participation in the education program. The anonymous survey revealed that 87.5% of participating residents believed that NICU fellows were very important to their overall training and education. CONCLUSIONS: While fellows are often believed to be a detracting factor to residency training, we found that pediatric resident attitudes toward the fellows were generally positive. In our experience, in the specialty of neonatology a fellow-led education program can positively contribute to both resident and fellow learning and satisfaction. Further investigation into the value of utilizing fellows as a positive force in resident education in other medical specialties appears warranted.