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Biomedical subjects

E W Nelson

Publications and source records attributed to E W Nelson.

At least 19 recordsLinked to original sources
PubMed2003

Laparoscopic treatment of post renal transplant lymphoceles.

BACKGROUND: Traditionally, a post transplant lymphocele (PTL) is drained by widely opening the wall connecting the lymphocele cavity to the intraperitoneal space via laparotomy. We hypothesize that laparoscopic techniques can be effectively used for the treatment of PTL. METHODS: Patients requiring intervention for PTL between 1993 and 2002 were identified via a retrospective review. Results of drainage via laparotomy and laparoscopy were compared. RESULTS: During the study period 685 renal transplants (391 cadaveric, 294 living) were performed. The incidence of lymphocele was 5% [34/685 (36 cases)]. The indications for surgical drainage were local symptoms (69%), graft dysfunction (14%), or both (17%). The mean time to surgical therapy was 4.9 months. Laparoscopic drainage was performed in 25 patients (74%) and open drainage in 9 patients (26%). Open procedures were performed in cases for: previous abdominal surgery (5), undesirable lymphocele characteristics or location (2), or with concomitant open procedures (3). There were no conversions or operative complications in either group. There was no difference in operative time for the laparoscopic group vs the open group (108 +/- 6 vs 123 +/- 18 min, p = 0.8). Hospital stay was significantly shorter for the laparoscopic group (1.7 +/- 0.8 vs 3.8 +/- 1.0, p = 0.0007), with 88% of laparoscopic patients being either overnight admissions or same day surgery. Two patients (5%) developed symptomatic recurrences requiring reoperation [1 laparoscopic (4%), 1 open (10%)]. CONCLUSIONS: Laparoscopic fenestration of a peritransplant lymphocele is a safe and effective treatment. The large majority of patients treated with laparoscopic fenestration were discharged within one day of surgery. Unless contraindications exist, laparoscopy should be considered first-line therapy for the surgical treatment of posttransplant lymphocele.

Adult↗
PubMed2000

Distal radial metaphyseal forces in an extrinsic grip model: implications for postfracture rehabilitation.

The purpose of this study was to establish the relationship between force at the distal radius and power grip force of the hand, a common functional and rehabilitation maneuver. This information will provide limits of allowable grip forces during postfixation rehabilitation and guide design requirements for fixation systems. By designing a model of power grip using the extrinsic hand musculotendinous units, we were able to compare grip force with force at the distal radius. Our results show that to obtain 10 N of grip force, approximately 26.3 N of force is transmitted through the distal radius, 52.4 N is transmitted through the radius and ulna combined, and 30.0 N needs to be applied to the flexor tendons. Fifty-one percent of the total forearm force was transmitted through the distal radius in this model. If all forearm forces were transmitted through the radius, 52 N of force would be transmitted through the distal radius to obtain 10 N of grip force. The clinical application of this model suggests that since failure forces of tested distal radius fixation systems range from 55 to 825 N, rehabilitation grip force should not exceed 10 to 159 N, depending on the type of fixation.

Biomechanical Phenomena↗
PubMed1999

Splenectomy in high-risk patients with splenomegaly.

BACKGROUND: Splenectomy in patients with massive splenomegaly and hematologic malignancy results in higher morbidity and mortality with primarily palliative benefit. METHODS: From a 14-year experience with 172 splenectomies, the perioperative course of 39 high-risk patients with splenomegaly was reviewed for comorbidities, indications, complications, and mortality. RESULTS: Twenty-three males and 16 females with a mean age of 54.2 years and a mean 12.8-day postoperative length of stay were reviewed. Sixteen patients (41%) had 23 major complications related to age (P = 0.047) and operative time (P = 0.01). Intraoperative transfusion was related to splenic size (P = 0.04), and estimated blood loss (P = 0.02) was inversely related to use of splenic artery preligation. Three perioperative deaths were secondary to sepsis and multi-organ system failure. CONCLUSION: Splenomegaly and comorbidities of the primary disease result in higher morbidity and mortality. Splenic artery preligation is valuable to limit intraoperative blood loss and facilitate splenectomy.

Comorbidity↗
PubMed1999

Gadolinium-enhanced breathhold three-dimensional time-of-flight renal MR angiography in the evaluation of potential renal donors.

PURPOSE: To evaluate the utility of gadolinium-enhanced three-dimensional (3D) time-of-flight (TOF) magnetic resonance angiography (MRA) of the renal arteries in the evaluation of potential renal donors. MATERIALS AND METHODS: Fifty consecutive patients underwent gadolinium-enhanced 3D-TOF MRA of the renal arteries as part of their evaluation as possible renal donors. All imaging was performed on a 1.5-T system with use of a torso phased-array coil. Conventional T1-weighted axial spin-echo and T2-weighted axial fast spin-echo imaging was performed to evaluate the renal parenchyma. Coronal dynamic MRA was performed during bolus injection of 40 mL of gadolinium with use of a 3D-TOF sequence requiring a breathhold of approximately 30 seconds. Maximum-intensity-projection reconstructions were obtained of the renal arterial and venous anatomy. All studies were prospectively evaluated by a single radiologist experienced with body MRA. Intraoperative findings were used as the reference standard in 35 patients. To evaluate interobserver variability, each examination was evaluated for image quality, renal artery number, and anatomy by two radiologists experienced with MRA and blinded to the other's interpretations and surgical results. RESULTS: Ninety-eight percent of all MRAs were graded as diagnostic quality (Kappa value = 0.38; P < .05). Multiple renal arteries were identified in 29 (29%) of 100 kidneys. Four of 50 patients studied (8%) had renal parenchymal abnormalities identified with MR imaging. Sensitivity and specificity for accessory renal artery detection was 71% and 95%, respectively. Overall, accuracy for MRA in determining renal artery number was 90%. CONCLUSION: Gadolinium-enhanced breathhold 3D-TOF renal MRA is sufficient to assess the renal arteries in potential donors.

Adult↗
PubMed1998

Distinct effects of allogeneic blood transfusion on splenocyte cytokine production after hemorrhagic shock.

UNLABELLED: Allogeneic blood transfusion is known to be immunosuppressive in the settings of cancer and transplantation, but the contribution of blood transfusion to immunomodulation after hemorrhage is unknown. Our purpose was to determine the influence of allogeneic blood transfusion upon cytokine profiles following hemorrhagic shock, using a model which approximates the clinical setting. METHODS: Male C3H/HeN mice were hemorrhaged via femoral arterial catheters to a mean arterial pressure (MAP) of 35 +/- 5 mm Hg, which was maintained for 1 h. Mice were resuscitated with autologous blood (auto BT) or allogeneic blood (allo BT) from Balb/c mice (both equivalent to volume of shed blood), and crystalloid (2X the volume of shed blood)-infused at 0.05 ml/min. Animals were sacrificed at 1, 2, and 5 days postshock, and splenocytes were cultured for 24 h with anti-CD3 antibody. Supernatants were assayed for IL-2, IL-6, IL-10, and gamma-IFN by ELISA. RESULTS: Regardless of transfusion status, hemorrhagic shock resulted in increased IL-6 and gamma-IFN by Day 2 postshock. Distinct cytokine alterations after allogeneic transfusion were as follows. IL-2: transient elevation of splenocyte IL-2 production in the shock + allo BT group (P < 0.005 vs. shock + auto BT) at Postshock Day 2. IL-6: suppression in IL-6 production in the shock + allo BT group by Postshock Day 5 (P < 0.05 vs. shock + auto BT). IL-10: persistently elevated IL-10 production following shock + allo BT (Day 1, P < 0.001 vs. shock + auto BT; Day 5; P < 0.05 vs. shock + auto BT). gamma-IFN: elevation in gamma-IFN production by Day 5 in the shock + allo BT group (P < 0.0005 vs. shock + auto BT). CONCLUSIONS: Allogeneic blood transfusion results in distinct alterations in splenocyte production of IL-2, IL-6, IL-10, and gamma-IFN after hemorrhagic shock. This model reflects the clinical usage of blood products and demonstrates some of the immune alterations after transfusion.

Animals↗
PubMed1998

Long-term cytokine alterations following allogeneic blood transfusion.

BACKGROUND: Allogeneic blood transfusion is associated with an increased risk of infection and higher cancer recurrence rates. Previous research has shown that blood transfusion results in multiple immune effects, including cytokine alterations. The purpose of this study was to measure the long term kinetics of splenocyte cytokine production in transfused mice. METHODS: Balb/c mice received either syngeneic transfusion (Syn-BT) or allogeneic transfusion (Allo-BT) from C3H-HeN mice. Splenocyte production of IL-2, IL-6, IL-10, and IFN-gamma was quantitated by ELISA on post-transfusion days 5, 10, 21, and 30. RESULTS: Both Allo-BT and Syn-BT produced significant alterations in cytokine production, but Allo-BT produced the most dramatic and enduring effects as summarized: IL-2: Production of IL-2 was suppressed at day 5, (p < 0.0001), but then rose, peaking at day 21, 30% greater than control values (p < 0.05). IL-6: Allo-BT mice showed suppression of IL-6 throughout the study period (p < 0.005 vs controls, each time point). IL-10: A 5-fold increase in IL-10 production was seen at day 5 after Allo-BT (p < 0.0001 vs control). Production of IL-10 was suppressed at days 10 and 21 (p < 0.001), but returned to control levels by day 30, gamma-IFN: At day 5 post Allo-BT, gamma-IFN was 4 x greater than controls (p < 0.0001). Gamma-IFN production was suppressed at day 10, but then rose at days 21 and 30 to nearly 3 x control levels (p < 0.0001). CONCLUSION: Allo-BT produced multiple cytokine alterations that were of prolonged duration. These results provide a theoretic explanation for the multiple, long-term immunomodulating effects seen in patients who have received transfusions.

Animals↗
PubMed1997

Stereotactic core needle biopsy and the workup of mammographic breast lesions.

OBJECTIVE: To evaluate the influence of stereotactic core needle biopsy (SCNB) as an alternative to wire localization biopsy (WLB) on the evaluation and workup of nonpalpable mammographic lesions. DESIGN: A 4-year retrospective clinical review. SETTING: University hospital and clinics. PATIENTS: All patients evaluated for nonpalpable mammographic lesions after screening, diagnostic mammography, or both during the 4-year period of the study were included. OUTCOME PARAMETERS: Changes in the number and types of mammograms and diagnostic biopsies and the histologic findings using each technique (SCNB vs WLB), including total number of cancers diagnosed. RESULTS: The number of screening mammograms and WLBs performed remained constant compared with a marked increase in the number of diagnostic mammograms and SCNBs. The rates of positive findings for each biopsy technique were consistent while the total number of cancers diagnosed increased dramatically. The percentage of biopsy specimens with positive results (ductal carcinoma in situ and invasive cancers) for SCNB was 13.3% compared with 26.2% for WLB specimens. There has also been an increase in the number of cancers found, from 22 in the first year to 54 in the fourth year. In the first year, 45% of these cancers were diagnosed by SCNB; in the fourth year, 83% of the cancers were diagnosed by SCNB. CONCLUSION: Stereotactic core needle biopsy has replaced WLB as the standard for the diagnostic biopsy of suspicious, nonpalpable mammographic lesions. Since adopting this technique, more patients have been examined and their conditions diagnosed as breast cancer in an efficient, cost-effective manner.

Algorithms↗
PubMed1996

Organ donors and nondonors. An American dilemma.

The principal motive for organ donation in the United States remains altruism. Surveys suggest that if the life-threatening and critical shortage of cadaveric donor organs were appropriately understood by the public, an altruistic response would lead to increased donation. However, despite intense educational efforts appealing to altruism, cadaveric organ donation has not increased substantially while the number of patients in need of a life-saving organ has grown markedly. To understand why organ donation has not increased, a telephone survey and focus group sessions of volunteers who were either for or against donation (donors and nondonors, respectively) were reviewed. The focus group nondonors demonstrated a remarkable lack of trust in the fairness of organ allocation and in the success of transplantation; indeed, this mistrust extended to the entire medical profession. The donors in the focus groups, on the other hand, believed that the system worked equitably, although their knowledge about organ donation and transplantation was equivalent to that of nondonors. For organ donation to increase, efforts must be directed toward those who are not convinced that donation is for the common welfare. One way to increase organ donation is for physicians to educate their patients better regarding the equity and success of transplantation.

Comprehension↗
PubMed1996

Magnetic resonance imaging characteristics of a lead pencil foreign body in the hand.

Foreign body detection and removal from the hand can present a challenging problem for the hand surgeon. Imaging studies often are of little help and may even be misleading regarding the size and location of the object. This article reports imaging techniques used in the detection of foreign bodies and presents a case in which magnetic resonance imaging was used to localize a lead-pencil foreign body in the hand prior to surgical removal. We also present the results of magnetic resonance imaging analysis of several lead pencils, showing a similar signal that indicates that iron and magnesium were responsible for the artifact seen on the magnetic resonance image.

Adult↗
PubMed1995

Thrombotic thrombocytopenic purpura: indications for and results of splenectomy.

BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a rare, life-threatening disorder of unknown pathophysiology. The role of splenectomy in the multimodality therapy of TTP is controversial. MATERIALS AND METHODS: All charts of patients with TTP at the University of Utah between 1984 and 1994 were reviewed to evaluate various treatment regimens, and specifically, the impact of splenectomy on morbidity and survival. RESULTS: Of the 15 patients identified, 14 underwent initial treatment with plasmapheresis and steroids. Nine patients were treated with medical therapy only, 6 of whom completely recovered, while 3 patients died. Six patients failed plasmapheresis and underwent splenectomy. There were no operative complications or postoperative deaths. All surgical patients had no active disease at last follow-up. CONCLUSION: Plasmapheresis and steroid administration remain the first-line therapy for TTP. This series documents that splenectomy offers excellent results with minimal morbidity and mortality in patients who do not respond to or who relapse after plasmapheresis.

Adult↗
PubMed1995

Selective use of image-guided large-core needle biopsy of the breast: accuracy and cost-effectiveness.

OBJECTIVE: We examined the accuracy and cost-effectiveness of large-core needle breast biopsy in a selected group of patients with mammographically detected lesions. MATERIALS AND METHODS: We selectively used large-core needle biopsy to sample breast lesions that were intermediate (neither clearly benign nor clearly malignant) and wire localization biopsy to sample breast lesions that were strongly suggestive of cancer. We compared 2 years' experience using this protocol with the preceding 2 years at the University of Utah Health Sciences Center during which we did only a few large-core needle biopsies on a nonselective basis. RESULTS: Our biopsy rate increased from one biopsy per 36 mammographic screening examinations to one per 26 (p = .001) when the protocol was used. The cost of biopsy per cancer detected decreased from $11,555 to $8356. The specificity of large-core needle biopsy was 98%; the sensitivity based on limited follow-up was 100%. CONCLUSION: Large-core needle biopsy is an accurate and cost-effective method for sampling breast lesions when used in a selective fashion.

Analysis of Variance↗
PubMed1994

The effects of oral pentoxifylline on the cytokine release syndrome during inductive OKT3.

The cytokine release syndrome (CRS) accompanying OKT3 therapy is a major cause of posttransplant morbidity. The pathogenesis of this syndrome has been attributed to the synthesis of tumor necrosis factor, interleukin 2 (IL-2), interleukin 6 (IL-6), and gamma-interferon in response on T lymphocyte stimulation by OKT3. The hemorrheologic agent pentoxifylline (PTX) inhibits the synthesis of TNF alpha in vitro in response to a variety of stimuli, including OKT3. We performed a randomized, double-blinded trial of PTX during OKT3 induction in recipients of cadaveric renal allografts. Patients received either PTX 800 mg or placebo 2 hr before the initial dose of OKT3 and every 8 hr thereafter during the first 3 posttransplant days. Serum TNF alpha and IL-6 concentrations were measured pre-OKT3 and at 2 and 6 hr post-OKT3 on the first 3 posttransplant days. Despite the achievement of apparently adequate plasma levels of PTX and its active metabolites, no difference was observed in the incidence or severity of clinical manifestations of CRS. Serious manifestations of CRS--including acute pulmonary edema, encephalopathy, and aseptic meningitis--were not seen in either group. Serum TNF alpha and IL-6 concentrations were similar in PTX and control patients throughout the course of the study. Plasma levels of PTX and its active metabolites did not correlate with serum TNF alpha levels, serum IL-6 levels, or the incidence and severity of clinical manifestations of CRS.

Adult↗
PubMed1991

Improving the use of early follow-up care after emergency department visits. A randomized trial.

OBJECTIVE: To test the hypothesis that the appropriateness of parents' use of early follow-up care after emergency department (ED) visits can be improved by postvisit support from a nurse practitioner. DESIGN: Randomized controlled trial, single blinded. SETTING: Urban university hospital ED linked to hospital's primary care center. PARTICIPANTS: Parents of 190 children younger than 8 years who sought care in the ED for acute illnesses and who were treated as outpatients with primary care center follow-up at the discretion of ED clinicians. INTERVENTION: Parents in the experimental group were called by a nurse practitioner who offered both individualized guidance regarding follow-up and access to a nurse practitioner for further help as needed. The control group received "usual" follow-up advice during ED visits. MEASUREMENTS/MAIN RESULTS: In the week after the ED visits, parents in the experimental group, compared with parents in the control group, were more compliant with instructions regarding follow-up (79% vs 61%), less apt to miss appointments (15% vs 31%), and less apt to "shop" elsewhere for care (2% vs 9%). Appropriateness of follow-up was assessed in "blinded" fashion using preestablished guidelines. Inappropriate use of follow-up care was significantly reduced among experimental group subjects (10% vs 20%). CONCLUSION: The nurse practitioner's intervention improved parents' use of follow-up care in our sample. Overall care for episodic ED users might be improved by similar interventions.

Aftercare↗
PubMed1990

Closure of refractory perineal Crohn's lesion. Integration of hyperbaric oxygen into case management.

A case is reported in which a comprehensive program of hyperbaric oxygen (HBO), surgical debridement and reconstruction, and continuing medical management resulted in complete and sustained closure of an extensive perineal Crohn's lesion refractory to conventional medical and surgical management. It is emphasized that in this case healing occurred in the setting of previous removal of all diseased intestinal tissue and only with the combined use of all three treatment modalities. HBO may be a useful adjunct in the therapy of large nonhealing perineal lesions post-proctocolectomy in patients who are unresponsive to metronidazole or to immunosuppressant therapy or who experience limiting side effects from continued medical therapy.

Combined Modality Therapy↗
PubMed1989

Major abdominal complications following cardiac transplantation. Utah Transplantation Affiliated Hospitals Cardiac Transplant Program.

Serious complications involving the alimentary tract are commonly reported following cardiac transplantation, and may be associated with significant morbidity and mortality. The aim of this report was to review the incidence, severity, and outcome of abdominal complications in our heart transplant population in whom we used corticosteroid-sparing protocols for immunosuppression. From March 1985 through September 1988, 178 patients underwent 185 cardiac transplants. Twenty-six cardiac transplant recipients (15%) sustained 33 major abdominal complications, including gastrointestinal bleeding (n = 8), pancreatitis (n = 8), bowel perforation (n = 6), cholecystitis (n = 4), and miscellaneous other problems (n = 7). Operative therapy was required in 61% of cases. No deaths were caused by the gastrointestinal complications of their operative management. Corticosteroid-sparing immunosuppression may be responsible for the low incidence of abdominal morbidity, and early, aggressive surgical intervention may reduce subsequent mortality.

Adult↗
PubMed1989

Effects of cyclopiazonic acid and aflatoxin singly and in combination on selected clinical, pathological and immunological responses of guinea pigs.

Cyclopiazonic acid (CPA) and aflatoxin are known sometimes to coexist in nature but little is known of possible biological interaction in mammals that consume mixtures of these two mycotoxins. Guinea pigs were dosed orally with CPA (2.2 mg/kg) or aflatoxin (0.045 mg B1/kg) singly or in combination. Effects of toxin consumption were determined on clinical health, body weight gain, pathological change, and several immunologically related parameters including delayed cutaneous hypersensitivity, antibody response, complement hemolytic titer, intracutaneous mitogen (PHA) and in vitro lymphocyte blastogenesis. In contrast to an earlier study by others, significant synergy between these two toxins was demonstrated in reduced rate of body weight gain, lethality and histologic changes (vacuolization) in hepatocytes. Reductions in complement titer, intradermal PHA, delayed cutaneous hypersensitivity response and in vitro lymphocyte blastogenesis were related to aflatin activity. No effects on antibody formation to Brucella abortus were observed with either toxin or the combination of toxins. Cyclopiazonic acid appeared to restore the suppressive effects of aflatoxin in delayed cutaneous hypersensitivity response and in vitro lymphocyte blastogenesis.

Administration, Oral↗