Comparing Patency Rates of Arteriovenous Dialysis Access following Percutaneous Thrombectomy Using Various Catheter Directed Therapies.

BACKGROUND: Arteriovenous fistulas often require frequent interventions to maintain patency for hemodialysis. Interventions may include open or percutaneous thrombectomy with additional targeted interventions as indicated. We evaluated the primary and cumulative functional patency rates following three unique approaches to percutaneous thrombectomy of thrombosed dialysis access. METHODS: A retrospective review of 236 unique patients who presented with thrombosed hemodialysis access was analyzed over a period of 4 years from 2016 to 2020. We analyzed a total of 413 procedures that utilized 3 separate percutaneous thrombectomy devices to assist with restoring patency. The Indigo System CAT-D Aspiration Thrombectomy Catheter (Penumbra; Alameda, CA), the Arrow-Trerotola Rotational Thrombectomy System (Teleflex; Wayne, PA) and the Angiojet Rheolytic Thrombectomy Catheter (Boston Scientific, Marlborough, MA) devices were compared for primary and cumulative functional patency. Primary patency was defined as time from percutaneous thrombectomy to next intervention (Angioplasty, stenting, and repeat thrombectomy). Cumulative functional patency was defined as time from percutaneous thrombectomy to time of access abandonment. Medical record chart review was utilized to determine patency rates. RESULTS: A total of 413 percutaneous thrombectomy procedures were performed. Of the procedures performed, 98 utilized Angiojet, 103 utilized Trerotola, and 212 used Penumbra. The mean primary patency rates in (days) for the devices were as follows: Angiojet (194), Trerotola (204), and Penumbra (107). The mean cumulative functional patency rates (in days) for the devices were as follows: rheolytic thrombectomy (450 days), aspiration thrombectomy (292 days), and rotational thrombectomy (475 days). Angiojet versus Penumbra and Trerotola versus Penumbra both showed diminished patency rates when using the Penumbra catheter that were statistically significant (P < 0.05). CONCLUSIONS: All percutaneous thrombectomy approaches do not result in the same primary or cumulative functional patency rates. Approaches with Trerotola and Angiojet resulted in improved primary and cumulative functional patency rates compared to those using Penumbra.

Results of pectus excavatum correction using a minimally invasive approach with subxyphoid incision and three-point fixation.

OBJECTIVES: This study reviews the results of our previously described modification of the minimally invasive (Nuss) procedure for correction of pectus excavatum. It utilizes a subxyphoid incision with central fixation to maximize safe bar passage and minimize bar displacement. METHODS: Consecutive patients corrected with the modified Nuss procedure between 2010 and 2015 form the basis of this study. RESULTS: During the study period, 73 patients had correction of their pectus excavatum by the modified Nuss procedure, utilizing subxyphoid incision and central fixation. Average age was 14.3 (range 8-19). 54 patients were male, 19 female. The average Haller index was 4.3 (range 3.2-7.2). No episodes of cardiac perforation, hemothorax or significant pneumothorax were recorded. Bar displacement occurred in two patients (2.7%) with one late recurrence after bar removal. CONCLUSIONS: Our modification of the Nuss procedure is effective at preventing intrathoracic complications and cardiac perforation. Central fixation had a lower rate of bar displacement compared to published reports. Additional efforts are needed to further reduce bar displacement.

Successful Percutaneous Retrieval of IVC Filter with Wide Retroperitoneal Penetration Presenting with Gastrointestinal Bleeding.

Symptomatic penetration of the retroperitoneal structures by inferior vena cava (IVC) filter is a rare clinical entity. Vast majority of these patients require laparotomy and open retrieval of the filter. We report a case of a filter penetrating into the duodenum within two months of implantation resulting in gastrointestinal bleeding. The patient was successfully managed with percutaneous retrieval of the filter, blood transfusion and serial abdominal examination thus avoiding laparotomy.

Use of granulocyte colony-stimulating factor during pregnancy in women with chronic neutropenia.

OBJECTIVE: To report outcomes associated with the administration of granulocyte colony-stimulating factor (G-CSF) to women with chronic neutropenia during pregnancy. METHODS: We conducted an observational study of women of childbearing potential with congenital, cyclic, idiopathic, or autoimmune neutropenia enrolled in the Severe Chronic Neutropenia International Registry to determine outcomes of pregnancies, without and with chronic G-CSF therapy, 1999-2014. Treatment decisions were made by the patients' personal physicians. A research nurse conducted telephone interviews of all enrolled U.S. women of childbearing potential using a standard questionnaire. Comparisons used Fisher's exact test analysis and Student's t test. RESULTS: One hundred seven women reported 224 pregnancies, 124 without G-CSF therapy and 100 on chronic G-CSF therapy (median dose 1.0 micrograms/kg per day, range 0.02-8.6 micrograms/kg per day). There were no significant differences in adverse events between the groups considering all pregnancies or individual mothers, for example, spontaneous terminations (all pregnancies: no G-CSF in 27/124, G-CSF in 13/100; P=.11, Fisher's exact test), preterm labors (all pregnancies, no G-CSF in 9/124, G-CSF in 2/100, P=.12). A study with at least 300 per group would be needed to detect a difference in these events with 80% statistical power (α=0.05). Four newborns of mothers with idiopathic or autoimmune neutropenia not on G-CSF (4/101) had life-threatening infections, whereas there were no similar events (0/90) in the treated group, but this difference was also not statistically significant (P=.124). Adverse events in the neonates were similar for the two groups. CONCLUSION: This observational study showed no significant adverse effects of administration of G-CSF to women with severe chronic neutropenia during pregnancy. LEVEL OF EVIDENCE: III.

Is USMLE Step 1 score a valid predictor of success in surgical residency?

BACKGROUND: Many programs rely extensively on United States Medical Licensing Examination (USMLE) scores for interviews/selection of surgical residents. However, their predictive ability remains controversial. We examined the association between USMLE scores and success in surgical residency. METHODS: We compared USMLE scores for 123 general surgical residents who trained in the past 20 years and their performance evaluation. Scores were normalized to the mean for the testing year and expressed as a ratio (1 = mean). Performances were evaluated by (1) rotation evaluations; (2) "dropouts;" (3) overall American Board of Surgery pass rate; (4) first-time American Board of Surgery pass rate; and (5) a retrospective comprehensive faculty evaluation. For the latter, 16 surgeons (average faculty tenure 22 years) rated residents on a 1 to 4 score (1 = fair; 4 = excellent). RESULTS: Rotation evaluations by faculty and "drop out" rates were not associated with USMLE score differences (dropouts had average above the mean). One hundred percent of general surgery practitioners achieved board certification regardless of USMLE score but trainees with an average above the mean had a higher first-time pass rate (P = .04). Data from the comprehensive faculty evaluations were conflicting: there was a moderate degree of correlation between board scores and faculty evaluations (r = .287, P = .001). However, a score above the mean was associated with a faculty ranking of 3 to 4 in only 51.7% of trainees. CONCLUSION: Higher USMLE scores were associated with higher faculty evaluations and first-time board pass rates. However, their positive predictive value was only 50% for higher faculty evaluations and a high overall board pass rate can be achieved regardless of USMLE scores. USMLE Step 1 score is a valid tool for selecting residents but caution might be indicated in using it as a single selection factor.

Recurrent neutropenic enterocolitis in a pediatric patient.

Management of an 8-year-old boy with Hodgkin lymphoma is presented. The patient had several recurrences of neutropenic enterocolitis and eventually required ileocecectomy. A review of the literature on this difficult problem affecting pediatric oncology patients is presented.

Genomic organization of zebrafish microRNAs.

BACKGROUND: microRNAs (miRNAs) are small (~22 nt) non-coding RNAs that regulate cell movement, specification, and development. Expression of miRNAs is highly regulated, both spatially and temporally. Based on direct cloning, sequence conservation, and predicted secondary structures, a large number of miRNAs have been identified in higher eukaryotic genomes but whether these RNAs are simply a subset of a much larger number of noncoding RNA families is unknown. This is especially true in zebrafish where genome sequencing and annotation is not yet complete. RESULTS: We analyzed the zebrafish genome to identify the number and location of proven and predicted miRNAs resulting in the identification of 35 new miRNAs. We then grouped all 415 zebrafish miRNAs into families based on seed sequence identity as a means to identify possible functional redundancy. Based on genomic location and expression analysis, we also identified those miRNAs that are likely to be encoded as part of polycistronic transcripts. Lastly, as a resource, we compiled existing zebrafish miRNA expression data and, where possible, listed all experimentally proven mRNA targets. CONCLUSION: Current analysis indicates the zebrafish genome encodes 415 miRNAs which can be grouped into 44 families. The largest of these families (the miR-430 family) contains 72 members largely clustered in two main locations along chromosome 4. Thus far, most zebrafish miRNAs exhibit tissue specific patterns of expression.