Intraprocedural Safety and Technical Success of the MVP Micro Vascular Plug for Embolization of Pulmonary Arteriovenous Malformations.

This case series describes early experience, intraprocedural safety, and technical success of the MVP Micro Vascular Plug (MVP; Covidien, Irvine, California) for embolization of 20 pulmonary arteriovenous malformations (PAVMs) using 23 plugs in seven patients with hereditary hemorrhagic telangiectasia. There was no device migration, and all devices were successfully detached electrolytically. Immediate cessation of flow through the feeding artery was achieved in 21 of 23 (91%) deployments. There was one minor complication. This series demonstrates the MVP to be safe and technically successful in the treatment of PAVMs.

Ethnic differences in arm vein diameter and arteriovenous fistula creation rates in men undergoing hemodialysis access.

OBJECTIVE: The National Kidney Foundation recommends that arteriovenous fistulas (AVFs) be placed in at least 65% of hemodialysis patients. Some studies suggest that African American patients are less likely to receive a first-time AVF than patients of other ethnicities, although the reason for this disparity is unclear. The purpose of our study is to determine (1) whether there are ethnic differences in AVF creation, (2) whether this may be related to differences in vein diameters, and (3) whether AVF patency rates are similar between African American and non-African American male patients. METHODS: Consecutive male patients undergoing first-time hemodialysis access from 2006 to 2010 at two institutions were retrospectively reviewed. Data collected included age, ethnicity, weight, height, body mass index, diabetes, hypertension, congestive heart failure, smoking history, intravenous drug abuse, need for temporary access placement, and preoperative venous ultrasound measurements. Categoric variables were compared using χ(2) analysis, and the Wilcoxon rank-sum test was used to compare continuous variables. RESULTS: Of 249 male patients identified, 95 were African American. Median age in African American and non-African American patients was 63 years. Hypertension and hyperlipidemia were statistically significantly greater in African American patients. The need for temporary access before hemoaccess was similar between the cohorts. African American patients demonstrated significantly smaller median basilic and cephalic vein diameters at most measured sites. Overall, 221 of 249 (88.8%) underwent AVF first. An AV graft was created in 17.9% of African American patients vs in only 7.1% of non-African Americans (odds ratio, 2.8; 95% confidence interval, 1.3-6.4; P = .009). The difference between median vein diameters used for autologous fistula creation in African American and non-African American patients was not significant. There was no significant difference in the primary patency (80.8% vs 76.2%; P = .4), primary functional patency (73.1% vs 69.2%; P = .5), or secondary functional patency rates (91.0% vs 96.5%; P = .1). Average primary fistula survival time was 257 days in African American and 256 in non-African American patients (P = .2). CONCLUSIONS: African American patients are less likely than non-African American patients to undergo AVF during first-time hemodialysis access surgery. This ethnic discrepancy appears to be due to smaller arm vein diameters in African American patients. In African American patients with appropriate vein diameters who do undergo AVF, primary and functional patencies are equivalent to non-African American patients.

A comparison between one- and two-stage brachiobasilic arteriovenous fistulas.

OBJECTIVES: Brachiobasilic arteriovenous fistulas (BBAVF) can be performed in one or two stages. We compared primary failure rates, as well as primary and secondary patency rates of one- and two-stage BBAVF at two institutions. METHODS: Patients undergoing one- and two-stage BBAVF at two institutions were compared retrospectively with respect to age, sex, body mass index, use of preoperative venous duplex ultrasound, diabetes, hypertension, and cause of end-stage renal disease. Categorical variables were compared using chi-square and Fisher's exact test, whereas the Wilcoxon rank-sum test was used to compare continuous variables. Patency rates were assessed using the Kaplan-Meier survival analysis and the Cox proportional hazards model with propensity analysis to determine hazard ratios. RESULTS: Ninety patients (60 one-stage and 30 two-stage) were identified. Mean follow-up was 14.2 months and the mean time interval between the first and second stage was 11.2 weeks. Although no significant difference in early failure existed (one-stage, 22.9% vs two-stage, 9.1%; P = .20), the two-stage BBAVF showed significantly improved primary functional patency at 1 year at 88% vs 61% (P = .047) (hazard ratio, 0.2 (95% confidence interval [CI], .04-.80; P = .03). Patency for one-stage BBAVF markedly decreased to 34% at 2 years compared with 88% for the two-stage procedure (P = .047). Median primary functional patency for one-stage BBAVF was 31 weeks (interquartile range [IQR], 11-54) vs 79 weeks (IQR, 29-131 weeks) for the two-stage procedure, respectively (P = .0015). Two-year secondary functional patency for one- and two-stage procedures were 41% and 94%, respectively (P = .015). CONCLUSIONS: Primary and secondary patency at 1 and 2 years as well as functional patency is improved with the two-stage BBAVF when compared with the one-stage procedure. Lower primary failure rates prior to dialysis with the two-stage procedure approached, but did not reach statistical significance. While reasons for these finding are unclear, certain technical aspects of the procedure may play a role.

Use of clinical triage criteria decreases monitored care bed utilization in gallstone pancreatitis.

Admission indicators for monitored care in gallstone pancreatitis have been lacking. Recently, we established three criteria for admission to intensive care unit or step down versus ward beds: (1) concomitant cholangitis, (2) heart rate >110 beats/min, and (3) blood urea nitrogen >15 mg/dL. The purpose of this study was to determine whether these criteria would be effective in decreasing monitored care bed utilization without adversely affecting outcomes. A retrospective review of all patients with gallstone pancreatitis at a public teaching hospital was performed (2003-2009). A comparison was made of patients before (2003-2005, Period 1) and after (2006-2009, Period 2) establishment of monitored care triage criteria. Over the study period, there were 379 patients. The median Ranson score for both periods was 1. The median ages were 41 and 39, (P = 0.7). In Period 1, 28 per cent of patients were admitted to the intensive care unit/step down unit versus 12 per cent in Period 2. None of the patients required transfer from the ward to a monitored care setting in Period 2. There were no mortalities in either period. In conclusion, the presence of concomitant cholangitis, heart rate >110, and blood urea nitrogen >15 are useful and safe triage criteria for admission to a monitored care setting. Use of these criteria significantly decreased monitored care bed utilization and resulted in fewer mis-triages without adversely affecting patient outcomes.

Acute care surgery performed by sleep deprived residents: are outcomes affected?

BACKGROUND: The Institute of Medicine recently recommended further reductions in resident duty hours, including a 5-h rest time for on-call residents after 16 h of work. This recommendation was purportedly intended to better protect patients against fatigue-related errors made by physician trainees. Yet no data are available regarding outcomes of operations performed by surgical trainees working without rest beyond 16 h in the current 80-h workweek era. METHODS: A retrospective review of all laparoscopic cholecystectomies (LC) and appendectomies performed by surgery residents at a public teaching hospital from July 2003 through March 2009. Operations after 10 PM were performed by residents who began their shift at 6 AM and had thus been working 16 or more hours. An outcomes comparison between time periods was conducted for operations performed between 6 AM and 10 PM (daytime) and 10 PM and 6 AM (nighttime). Outcome measures were rates of total complications, bile duct injury, conversion to open operation, length of surgery, and mortality. RESULTS: Over the 7-y study period, 2908 LC and 1726 appendectomies were performed. Appendectomies were performed laparoscopically in 73% of cases in patients for both time periods. There were no differences in rates of overall morbidity and mortality for operations when performed in nighttime compared with daytime. On multivariable analysis, there were no differences in outcomes between the two groups. CONCLUSION: The two most commonly performed general surgical operations performed at night by unrested residents have favorable outcomes similar to those performed during the day. Instituting a 5-h rest period at night is unlikely to improve the outcomes for these commonly performed operations.

Popliteal artery pseudoaneurysm after isolated hyperextension of the knee.

We report an unusual case of a traumatic pseudoaneurysm of the popliteal artery after an isolated blunt hyperextension injury to the knee. A 56-year-old man presented with a 1-month history of left knee pain that occurred after a fall onto his buttocks with hyperextension of the knee while transferring a relative out of a wheelchair. A large pulsatile mass in the posterior aspect of the left knee was palpated on physical examination, although he had warm distal extremities and 2+ distal pulses bilaterally. Magnetic resonance angiography revealed a 7.6 × 6.2 × 4.9 cm left popliteral artery pseudoaneurysm, which was subsequently treated with aneurysm exclusion with end to end reverse saphenous vein graft bypass. The development of a popliteal artery pseudoaneurysm after blunt knee injury without dislocation, fracture, or ligament injury is extremely unusual, but requires prompt treatment to avoid the potential complications of permanent functional impairment and limb loss.

A survey of demographics, motivations, and backgrounds among applicants to the integrated 0 + 5 vascular surgery residency.

OBJECTIVE: The 0 + 5 integrated vascular surgery (VS) residency has altered the training paradigm for future vascular specialists. Rising interest in these novel programs highlights our need to better understand the applicant pool. We compared demographics and surveyed recent applicants to our integrated program to gain more insight into their background and motivation for accelerated vascular training. METHODS: Demographics and objective parameters were determined from all 65 applicants to the integrated VS program at Stanford University Medical Center and compared to 58 applicants interviewed by the general surgery (GS) program at Harbor-UCLA Medical Center by querying the Electronic Residency Application System for the programs in 2009. There was no overlap of applicants between programs. An anonymous, voluntary Web-based survey was sent to these cohorts with a response rate of 82% for VS applicants and 60% for GS applicants. Subjects were queried regarding their background, personal experience, prior exposure to VS, and motivations for residency specialty selection. RESULTS: Applicants to integrated VS programs tended to be older, were less likely to be from a US medical school, had a higher number of publications, and a higher percentage of cardiovascular-related publications than the GS applicants. When stratified by the 27 VS applicants (41%) that were offered an interview, this highly selected and desirable group for training was nearly 40% female, more likely to have an additional degree (PhD, master's), just as likely to be in the top quartile of their medical school class (60%), and score equally well on standardized board examinations (90th percentile) than the top GS applicants offered interviews. Survey data revealed that the majority of career choices (65%) were made during the third and fourth years of medical school. Factors most strongly influencing the decision to choose VS as a career were endovascular technologies/devices, challenging open vascular operations, clinical rotations on vascular surgery, the aging patient population, and perceived need for vascular surgeons and vascular surgeon mentorship. The most common reasons cited for particularly pursuing an integrated 0 + 5 VS training program were (1) more focused training/integration of cardiovascular medicine, (2) interest in catheter-based endovascular therapies, and (3) shorter time in training. Of the GS applicants, 58% indicated they would be interested in applying to an integrated residency in their subspecialty of interest, and 45% listed vascular surgery as a potential fellowship option after general surgery. CONCLUSION: Applicants to 0 + 5 integrated vascular residencies were more likely to have rotated on a vascular surgery service, observed vascular cases, identified a vascular surgery mentor, and been actively involved in cardiovascular research. The quality of the top VS applicant based on class rank and test scores is comparable to the top GS applicants, yet the VS applicant has a higher percentage of advanced degrees, more publications, and more involvement in cardiovascular research. Institutional strategies to increase medical student exposure to vascular surgery clinically and via research programs will optimize our ability to attract and train the best candidates in these new training programs.

Acute thrombosis of an abdominal aortic aneurysm followed by delayed rupture associated with bacterial infection.

Sudden thrombosis of an abdominal aortic aneurysm (AAA) is distinctly rare and is associated with up to 50% mortality. Almost equally rare is infection of a preexisting AAA. We report an extremely unusual case of an AAA that thrombosed leading to acute limb ischemia. This was followed several months later by a delayed rupture of the thrombosed AAA associated with an Escherichia coli infection. We suspect the aortic thrombus was hematogenously seeded by a urinary tract infection. A review of the literature revealed that bacterial infection of a previously thrombosed AAA, leading to a delayed rupture, has not been previously reported.

Iatrogenic pseudoaneurysm of the superior gluteal artery presenting as pelvic mass with foot drop and sciatica: case report and review of literature.

We report an unusual case of a pseudoaneurysm of the superior gluteal artery as a complication of bone marrow biopsy. A 51-year-old man presented with sciatic pain and foot drop after undergoing bone marrow biopsy and was initially diagnosed as having degenerative disc disease based on his past medical history. Pelvic magnetic resonance imaging (MRI) revealed a large heterogeneous mass suggestive of a neurogenic tumor, but pulsatile blood was instead encountered during computed tomography (CT)-guided needle biopsy. Subsequent workup established the diagnosis of a superior gluteal artery pseudoaneurysm, which was treated with coil embolization, followed by surgical evacuation of the hematoma, which relieved his sciatic pain. However, the patient continues to have a persistent foot drop. Gluteal artery pseudoaneurysms are exceedingly uncommon but should be considered in the workup of a patient with gluteal pain or sciatic nerve palsy following trauma or medical procedures in the gluteal region.