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Robert J Feezor

Publications and source records attributed to Robert J Feezor.

13 recordsLinked to original sources
PubMed2007

Perioperative differences between endovascular repair of thoracic and abdominal aortic diseases.

BACKGROUND: With the US Food and Drug Administration approval of the TAG thoracic device, more thoracic pathologies are being treated using endovascular techniques. Although endovascular abdominal and thoracic aortic repairs have some apparent similarities, there are substantive anatomic, pathologic, and technical differences that could impact perioperative outcomes. The purpose of this study is to identify these differences. METHODS: During a 5-year period, 121 endovascular thoracic aortic repairs (TEVAR) and 450 abdominal aortic repairs (EVAR) were performed at a single institution. Preoperative, intraoperative, and early postoperative data were prospectively collected and retrospectively reviewed. Aggregate outcome measures were compared between the two cohorts, with statistical significance achieved at P < .05. RESULTS: The mean age of patients undergoing EVAR was 72.8 +/- 8.3 compared with 68.3 +/- 13.9 for TEVAR (P = .02). More women underwent TEVAR (30.6% vs 11.1%, P < .001). Aneurysms undergoing TEVAR were larger than those for EVAR (62.0 mm vs 58.3 mm, P = .01). Intraoperatively, EVAR required 26.2 minutes of fluoroscopy compared with 22.1 minutes for TEVAR (P < .001). The amount of contrast used was higher in TEVAR (133.6 mL vs 93.6 mL, P < .001). The mean procedure times were 164 minutes for EVAR and 115 minutes for TEVAR (P < .001). Iliac conduits were required in 46 patients (10.2%) undergoing EVAR, and in 24 (19.8%) undergoing TEVAR (P = .007). The 30-day or in-hospital mortality was 2.0% for EVAR and 5.0% for TEVAR (P = NS). The median length of stay was longer for TEVAR (3 days vs 2 days, P =.034). There were 54 postoperative complications in 36 TEVAR patients (29.8%), including 13 neurologic (10.7%), 8 renal (6.6%), 7 pulmonary (5.8%), 6 ischemic (5.0), and 5 (4.1%) hemorrhagic events. Among the EVAR group, 136 (30.2%) patients had postoperative complications, which included 45 ischemic (10.0%), 34 wound (7.6%), 22 renal (4.9%), 12 cardiac (2.7%), 8 pulmonary (1.8%), 5 gastrointestinal (1.1%), and 4 neurologic (0.9%) events. CONCLUSIONS: A relatively higher proportion of women underwent TEVAR than EVAR, and this was reflected in the greater need for iliac conduits to accommodate the larger delivery catheters of the thoracic devices. Intraoperative imaging techniques were also different, and TEVAR required higher contrast volumes despite shorter overall procedure times. The incidence of strokes and spinal cord ischemia was also higher during TEVAR. Despite apparent similarities of devices and techniques, EVAR and TEVAR are fundamentally different procedures with different perioperative outcomes.

Adult↗
PubMed2006

Laparoscopic repair of a type II endoleak.

A 72-year-old male underwent an uncomplicated endovascular repair of a 6.1-cm infrarenal abdominal aortic aneurysm. Routine follow-up at 18 months postoperatively revealed the presence of a type II endoleak, and that the aneurysm had increased in size. The endoleak was repaired by laparoscopic ligation of the inferior mesenteric artery. A postoperative computerized tomography scan revealed cessation of flow through the inferior mesenteric artery. The patient tolerated the procedure well and was discharged home on the same day.

Aged↗
PubMed2005

Functional genomics and gene expression profiling in sepsis: beyond class prediction.

Functional genomics involving genome-wide expression analyses is rapidly finding applications in clinical medicine. New technologies now permit the simultaneous analysis of mRNA levels for the entire human transcriptome from as few as 1000 cells. This approach is dramatically changing the way we define health and disease, allowing, for the first time, an unbiased view of the global changes in gene expression that are occurring. For the study of trauma biology and sepsis, this technology offers a powerful tool to develop molecular signatures for inflamed tissues and specific cell populations. At present, functional genomics is being used to classify the progress of disease and survival in response to traumatic and burn injury, sepsis and visceral ischemia, and reperfusion injury, as well as to describe patterns of gene expression in response to varying microbial pathogens. As the number of bioinformatics tools increases, functional genomics is beginning to reveal the underlying complexity of the biological response to a variety of inflammatory diseases and is providing new approaches for their exploration. Functional genomics is becoming a standard tool in inflammation research as a means to unravel the basic biological processes.

Animals↗
PubMed2004

Whole blood and leukocyte RNA isolation for gene expression analyses.

The analysis of gene expression data in clinical medicine has been plagued by the lack of a critical evaluation of accepted methodologies for the collection, processing, and labeling of RNA. In the present report, the reliability of two commonly used techniques to isolate RNA from whole blood or its leukocyte compartment was compared by examining their reproducibility, variance, and signal-to-noise ratios. Whole blood was obtained from healthy subjects and was either untreated or stimulated ex vivo with Staphylococcus enterotoxin B (SEB). Blood samples were also obtained from trauma patients but were not stimulated with SEB ex vivo. Total RNA was isolated from whole blood with the PAXgene proprietary blood collection system or from isolated leukocytes. Biotin-labeled cRNA was hybridized to Affymetrix GeneChips. The Pearson correlation coefficient for gene expression measurements in replicates from healthy subjects with both techniques was excellent, exceeding 0.985. Unsupervised analyses, including hierarchical cluster analysis, however, revealed that the RNA isolation method resulted in greater differences in gene expression than stimulation with SEB or among different trauma patients. The intraclass correlation, a measure of signal-to-noise ratio, of the difference between SEB-stimulated and unstimulated blood from healthy subjects was significantly higher in leukocyte-derived samples than in whole blood: 0.75 vs. 0.46 (P = 0.002). At the P < 0.001 level of significance, twice as many probe sets discriminated between SEB-stimulated and unstimulated blood with leukocyte isolation than with PAXgene. The findings suggest that the method of RNA isolation from whole blood is a critical variable in the design of clinical studies using microarray analyses.

Adolescent↗
PubMed2004

Genomic and proteomic determinants of outcome in patients undergoing thoracoabdominal aortic aneurysm repair.

Thoracoabdominal aortic aneurysm repair, with its requisite intraoperative mesenteric ischemia-reperfusion, often results in the development of systemic inflammatory response syndrome, multiorgan dysfunction syndrome (MODS), and death. In the present study, an adverse clinical outcome following thoracoabdominal aortic aneurysm repair was identified by blood leukocyte genomic and plasma proteomic responses. Time-dependent changes in the expression of 146 genes from blood leukocytes were observed (p < 0.001). Expression of 138 genes (p < 0.001) and the concentration of seven plasma proteins discriminated between patients who developed MODS and those who did not, and many of these differences were evident even before surgery. These findings suggest that changes in blood leukocyte gene expression and plasma protein concentrations can illuminate pathophysiological processes that are subsequently associated with the clinical sequelae of systemic inflammatory response syndrome and MODS. These changes in gene expression and plasma protein concentrations are often observed before surgery, consistent with either a genetic predisposition or pre-existing inflammatory state.

Aged↗
PubMed2004

Temporal patterns of gene expression in murine cutaneous burn wound healing.

The global changes in gene expression in injured murine skin were characterized following a second-degree scald burn. Dorsal skin was harvested from uninjured and from burned mice at 2 h and at 3 and 14 days following immersion in 65 degrees C water for 45 s. Gene expression was surveyed using an Affymetrix U74Av2 GeneChip, and patterns of gene expression were analyzed using hierarchical clustering and supervised analysis. Burn injury produced significant alterations in the expression of a number of genes, with the greatest changes seen 3 and 14 days after the scald burn. Using a supervised analysis with a false discovery rate of 1% or 5%, differences in the expression of 192 or 1,116 genes, respectively, discriminated among the unburned skin and the three time points after the burn injury. Gene expression was primarily a transient and time-dependent upregulation. The expression of only 24 of the 192 discriminating genes was downregulated after the burn injury. No gene exhibited a sustained increase in expression over the entire 14 days following the burn injury. Gene ontologies revealed an integrated upregulation of inflammatory and protease genes at acute time intervals, and a diminution of cytoskeletal and muscle contractile genes at 3 or 14 days after the injury. Following a second-degree scald burn, global patterns of gene expression in the burn wound change dramatically over several weeks in a time-dependent manner, and these changes can be categorized based on the biological relevance of the genes.

Animals↗
PubMed2004

Should decisions on internal mammary lymph node irradiation be based on current lymphoscintigraphy techniques for sentinel lymph node identification?

BACKGROUND: Treatment of internal mammary lymph node (IMN) metastases remains controversial because of the difficulty in predicting involvement, potential treatment-related morbidity, and questionable efficacy. Lymphoscintigraphy with sentinel lymph node biopsy offers a means to identify occult involvement of IMN, allowing appropriate patient selection for IMN treatment. METHODS: The authors retrospectively reviewed 262 lymphoscintigraphies (LS) of 248 patients treated at the University of Florida (Gainesville, FL) between 1998 and 2002. Tumor characteristics were assessed for their value in predicting IMN drainage and their association with IMN radiation. RESULTS: Lymph flow to the IMN was documented with LS in 23 of 262 tumor specimens (9%). Flow to the IMN was not correlated with any of the five factors: tumor location, tumor size, lymphovascular invasion, pathologic lymph node status, and laterality of the involved breast (right vs. left breast). Identification of IMN flow increased from 5.7% to 10.1% with the use of a deep injection technique. IMN radiotherapy was used more frequently in patients with larger tumors (15 of 188 in Tis/T1 vs. 31 of 70 in T2-T4; P<0.0001) and positive lymph nodes (17 of 91 in lymph node-negative patients vs. 28 of 66 in lymph node-positive patients; P<0.0001). In patients with T2N0 tumors (n=32), IMN radiotherapy was used more frequently with medial tumors (5 of 11 [45%]) than with lateral tumors (4 of 21 [19%]). CONCLUSIONS: The incidence of flow to the IMN documented with the current LS technique was low compared with other LS and extended radical mastectomy series. Histopathologic information was obtained for the sentinel IMN when IMN flow was identified on the LS. In the absence of histopathologic information, treatment decisions should continue to be based on clinical factors known to be correlated with occult IMN involvement.

Adult↗
PubMed2003

Molecular characterization of the acute inflammatory response to infections with gram-negative versus gram-positive bacteria.

Sepsis caused by gram-negative bacteria and that caused by gram-positive bacteria often manifest similar clinical features. We investigated plasma proinflammatory cytokine profiles in patients with sepsis due to gram-positive and gram-negative bacteria and studied the cytokine production and differential gene regulation of leukocytes stimulated ex vivo with Escherichia coli lipopolysaccharide or heat-killed Staphylococcus aureus. Concentrations of tumor necrosis factor alpha, interleukin 1 receptor antagonist (IL-1Ra), IL-8, IL-10, IL-18 binding protein, procalcitonin, and protein C in plasma did not differ between patients with sepsis due to gram-negative and gram-positive bacteria. However, plasma IL-1beta, IL-6, and IL-18 concentrations were significantly higher in patients with sepsis due to gram-positive bacteria. Ex vivo stimulation of whole blood with heat-killed S. aureus markedly increased IL-1beta and IL-18 levels more than E. coli lipopolysaccharide stimulation. Microarray analysis revealed at least 359 cross-validated probe sets (genes) significant at the P < 0.001 level whose expression discriminated among gram-negative-organism-stimulated, gram-positive-organism-stimulated, and unstimulated whole-blood leukocytes. The host inflammatory responses to gram-negative and gram-positive stimuli share some common response elements but also exhibit distinct patterns of cytokine appearance and leukocyte gene expression.

Cytokines↗
PubMed2003

Principles of immunology.

The immune system, composed of innate and acquired immunity, allows an organism to fight off foreign pathogens. Healthy immunity accomplishes four essential principles: (1) ability to detect and fight off infection; (2) ability to recognize a host's own cells as "self," thereby protecting them from attack; (3) a memory from previous foreign infections; and (4) ability to limit the response after the pathogen has been removed. In an unaltered state, the intricate network of immunologic organs and cells creates an environment for proper host defense. Without adequate execution of immunologic mechanisms, a host is rendered defenseless against pathogens. Conversely, an unchecked immune response can be self-destructive. As a result of either of these untoward sequelae, immune dysfunction can elicit disease states in the host. The goal of this review is to elucidate the characteristics of a healthy immune system, focusing on the principles of immunity and the cells that participate in host protection. We also briefly discuss the clinical ramifications of immune dysfunction.

Journal Article↗
PubMed2002

Duodenal perforation with an inferior vena cava filter: an unusual cause of abdominal pain.

The insertion of inferior vena cava (IVC) filters results in device migration at rates that exceed 50% in some studies, although the clinical significance of migration remains in question. These filters can also erode or penetrate the IVC wall, injuring adjacent retroperitoneal and abdominal structures. The risk of erosion or perforation is estimated to be as much as 25%, although clinical symptoms are observed far less frequently in patients with these complications. We describe the presentation, evaluation, and treatment of a patient with an IVC strut protruding into the duodenum. This case report discusses complications, presenting symptoms, and treatment of patients with IVC filters complications.

Abdominal Pain↗
PubMed2002

Sequential dermal-peritumoral radiocolloid injection for sentinel node biopsy for breast cancer: the University of Florida experience.

Although sentinel lymph node (SLN) biopsy is rapidly becoming the standard of care for small breast cancers the optimal radiocolloid injection technique remains controversial. We report our experience with sequential dermal-peritumoral radiocolloid injection that takes advantage of both techniques. One hundred eighteen patients with clinical stage T(is), T1, T2 and N0 breast cancer underwent SLN biopsy at the University of Florida. Twelve to 18 hours before surgery patients received either an injection of 0.5 to 1.0 mCi 50:50 filtered:unfiltered technetium sulfur colloid into the dermis overlying the tumor and/or a peritumoral injection of a 3 to 4-mCi of radiocolloid 30 minutes later. Dynamic lymphoscintigraphy was performed and the topographical location of all imaged lymph nodes was marked on the skin. The next morning the surgeon utilized a hand-held gamma probe to remove all SLN(s) defined as any lymph node with radioactive counts 10 per cent or more of the ex vivo counts of the most radioactive SLN [internal mammary (IM) nodes were not removed]. The SLN identification rate was 98.5 per cent (3 IM nodes) for dermal injection (d.), 83.3 per cent (1 IM node) for peritumoral injection (p.), and 100 per cent (14 IM nodes) for sequential dermal-peritumoral injection (d.p.) (p < 0.05 DP versus D). Sequential d.p. 50:50 filtered:unfiltered technetium sulfur colloid injection results in a rapid, high SLN identification rate that persists until surgery the next morning. Delineation of nonaxillary SLNs may lead to more accurate breast cancer staging and may also influence the delivery of IM node radiation.

Aged↗