Biomedical subjects

Robert G Sawyer

Publications and source records attributed to Robert G Sawyer.

At least 19 recordsLinked to original sources

PubMed2007

Cost of Gram-negative resistance.

OBJECTIVE: It is unclear that infections with Gram-negative rods resistant to at least one major class of antibiotics (rGNR) have a greater effect on patient morbidity than infections caused by sensitive strains (sGNR). We wished to test the hypothesis that rGNR infections are associated with higher resource utilization. DESIGN: Retrospective observational cohort study of prospectively collected data. SETTING: University hospital surgical intensive care unit and ward. PATIENTS: Surgical patients with at least one GNR infection. MEASUREMENTS: We compared admissions treated for rGNR infection with those with sGNR infections. Primary outcomes were total hospital costs and hospital length of stay. Other outcomes included antibiotic treatment cost, in-hospital death, and intensive care unit length of stay. After univariate analysis comparing outcomes after rGNR infection with those after sGNR infection, multivariate linear regression models for hospital cost and length of stay were created to account for potential confounders. MAIN RESULTS: Cost data were available for 604 surgical admissions treated for at least one GNR infection (Centers for Disease Control and Prevention criteria), 137 (23%) of which were rGNR infections. Admissions with rGNR infections were associated with a higher severity of illness at the time of infection (Acute Physiology and Chronic Health Evaluation II score, 17.6 +/- 0.6 vs. 13.9 +/- 0.3), had higher median hospital costs ($80,500 vs. $29,604, p < .0001) and median antibiotic costs ($2,607 vs. $758, p < .0001), and had longer median hospital length of stay (29 vs. 13 days, p < .0001) and median intensive care unit length of stay (13 days vs. 1 day, p < .0001). Infection with rGNR within the first 7 days of admission was independently predictive of increased hospital cost (incremental increase in median hospital cost estimated at $11,075; 95% confidence interval, $3,282-$20,099). CONCLUSIONS: Early infection with rGNR is associated with a high economic burden, which is in part related to increased antibiotic utilization compared with infection with sensitive organisms. Efforts to control overuse of antibiotics should be pursued.

Analysis of Variance↗

PubMed2006

Part-time training in general surgery: results of a web-based survey.

HYPOTHESIS: The recent increase in female medical school enrollment and emphasis on lifestyle considerations for both men and women pose challenges for residency recruitment and retention. This study was designed to assess interest in part-time surgical training. We hypothesized that more women than men would be interested in this option. DESIGN: A Web-based survey soliciting demographic information and opinions about training priorities was distributed to medical students, surgery residents, fellows, and trained surgeons. Respondents were asked to express on a 5-point Likert scale interest in (and deterrents to) substituting 1 or more years of standard residency with a shorter workweek (< 80 hours but > 40 hours) in exchange for a proportionately overall longer length of training. SETTING: The survey was located on the American College of Surgeons Web site. PARTICIPANTS: Medical students (482), surgical residents (789), fellows (179), and fully trained surgeons (2858) affiliated with at least 1 of 4 major surgical societies. RESULTS: There were 4308 respondents (76% male). Of physician respondents, 9.1% had taken time out of residency for nonresearch reasons. Thirty-six percent of female and 24% of male students agreed to increased interest in surgical careers if part-time training were an option (P = .005). Twenty-five percent of female and 13% of male residents (P<.001) expressed interest in this option. Prolonged training was cited as the primary deterrent. CONCLUSIONS: Eleven percent to 36% of total male and female respondents expressed interest in pursuing part-time training. Significantly more women than men favored a part-time option.

Adult↗

PubMed2006

Anastomotic leak and the loop ileostomy: friend or foe?

PURPOSE: Anastomotic disruption is an uncommon but morbid complication of colon and rectal surgery. This study was designed to evaluate the use of proximal diversion and surgical drainage as an alternative to anastomotic resection in the operative management of patients with anastomotic complications. METHODS: A retrospective chart review was undertaken of all patients on the colon and rectal surgery service at an academic medical center requiring operative intervention for an anastomotic complication between 1998 and 2005. Demographic data, operative management, morbidity, and mortality were collected and analyzed for each patient. RESULTS: Twenty-seven patients with anastomotic leaks were included in the study. Nineteen patients were managed with proximal diversion and surgical drainage, six patients had resection of their anastomosis and creation of an end colostomy, and two patients were treated by primary reanastomosis. There was 0 percent mortality. Sixty-three percent of the patients treated with proximal diversion had restoration of intestinal continuity vs. 33 percent of the patients who had the anastomosis resected. Of the 13 patients treated with proximal diversion who underwent fluoroscopic evaluation, 92 percent were normal without evidence of persistent leak or stricture. CONCLUSIONS: Based on this retrospective study, proximal diversion without resection of the anastomosis seems to be a safe and effective alternative for the treatment of anastomotic complications. Sepsis is well controlled with limited mortality and there is a high rate of anastomotic salvage. Prospective studies are needed to further delineate the optimal management for this complicated patient population.

Adult↗

PubMed2006

The other fungi: it's not just Candida albicans anymore.

BACKGROUND: Candida albicans continues to be the fungus most often causing disease in surgical patients, but with the treatment of an increasing number of critically ill and immunosuppressed patients, other candidal and non-candidal fungal pathogens are becoming more common. METHODS: Review of current practice and guidelines. RESULTS: The presentation and management of non-C. albicans fungal infections differs depending on the genus and species. The availability of newer anti-fungal agents has in many cases improved outcomes or decreased toxicities associated with these diseases. CONCLUSIONS: Although such infections are still relatively uncommon, a working knowledge of infections with non-C. albicans fungi may be beneficial for surgeons, who are likely to encounter such patients both primarily and in consultation. Prompt recognition and treatment of these diseases should improve outcomes.

Cross Infection↗

PubMed2006

Does enteral glutamine supplementation decrease infectious morbidity?

BACKGROUND: Although some studies have demonstrated lower infectious morbidity in patients receiving supplemental glutamine, there remains no consensus on the utility of such treatment. This study was designed to investigate the effects of supplemental enteral glutamine on the rate and outcomes of infection in critically ill surgical patients. METHODS: All 185 surgical and trauma patients admitted to a single university surgical trauma intensive care unit (STICU) over an approximately three-year period who were to receive enteral nutrition support were assigned sequentially to one of three diets: standard 1-kCal/mL feedings with added protein (Group 1), standard feedings with glutamine 0.6 g/kg per day (Group 2), or immune-modulated feedings with a similar amount of glutamine (Group 3). Group compositions and patient characteristics were similar at baseline. Data were collected prospectively on infections acquired during hospitalization. RESULTS: A total of 119 patients had at least one infection: 59% of the patients in Group 1, 64% of Group 2, and 69% of Group 3 (p = NS). There were no differences among the groups in the mean number of infections. The most common sites in all groups were the lungs, blood, and urine; and the frequencies of these infections did not differ between groups. Minor differences were found between groups in the organisms isolated. Antibiotic usage did not differ. CONCLUSION: Supplemental enteral glutamine in the dose studied does not appear to influence the acquisition or characteristics of infection in patients admitted to a mixed STICU.

Adult↗

PubMed2006

Can we define the ideal duration of antibiotic therapy?

BACKGROUND: Because of the increasing development of antimicrobial resistance, there is a greater responsibility within the medical community to limit the exposure of patients to antibiotics. We tested the hypothesis that shorter courses of antibiotics are associated with similar or better results than longer durations. We also sought to investigate the difference between a fixed duration of therapy and one based on physiologic measures such as fever and leukocytosis. METHODS: All infectious episodes on the general surgery units of the University of Virginia Health System from December 15, 1996, to July 31, 2003, were analyzed retrospectively for the relation between the duration of antibiotic therapy and infectious complications (recurrent infection with the same organism or at the same site). All infections associated with either fever or leukocytosis were categorized into quartiles on the basis of the absolute length of antibiotic administration or the duration of treatment following resolution of fever or leukocytosis. Multivariate logistic regression models were developed to estimate the independent risk of recurrence associated with a longer duration of antibiotic use. RESULTS: Of the 5,561 treated infections, 4,470 were associated with fever (temperature > or =38 degrees C) or leukocytosis (white blood cell count > or =11,000/mm(3)). For all infections, whether analyzed by absolute duration or time from resolution of leukocytosis or fever, the first or second quartiles (0-12 days, 0-9 days, 0-9 days, respectively) were associated with the lowest recurrence rates (14-18%, 17-23%, 18-19%, respectively). Individual analysis of intra-abdominal infections and pneumonia yielded similar results. The fixed-duration groups received fewer days of antibiotics on average, with outcomes similar to those in the physiologic parameters group. CONCLUSIONS: Shorter courses of antibiotics were associated with similar or fewer complications than prolonged therapy. In general, adopting a strategy of a fixed duration of therapy, rather than basing duration on resolution of fever or leukocytosis, appeared to yield similar outcomes with less antibiotic use.

Adult↗

PubMed2006

Prevention of surgical site infections.

In the current era of pay-for-performance standards, the incidence of surgical site infections is increasingly becoming an institutional marker of quality assurance. Surgical site infections lead to increased morbidity and mortality in the surgical population and contribute to an already rising healthcare cost. As a result, the surgical community goes to great lengths to prevent this costly and occasionally lethal complication. Many practices are evidence based, however, many are not. In this article, the most commonly used preventive strategies in practice today and the evidence behind each are reviewed. In addition, an overview of the epidemiology, pathophysiology and microbiology of surgical site infections will be provided.

Anti-Bacterial Agents↗

PubMed2006

Screening practices of patients presenting for resection of a colorectal neoplasm.

Multiple studies demonstrate the efficacy of colorectal cancer (CRC) screening in patients over 50 years of age. However, there is a lack of consensus regarding which screening method to use, and compliance has been poor. The objective of this study was to identify the CRC screening practices at two institutions and determine the relationship between screening and pathologic stage for patients presenting with a colorectal neoplasm. This study, conducted at the University of Virginia (UVA) Health System and the Salem Veterans Affairs Medical Center (VAMC) between October 30, 2000, and September 1, 2004, included 198 patients > or = 50 years who presented for resection of a primary colorectal neoplasm. Pathologic stage and prior screening were identified retrospectively through chart review and patient response to an anonymous survey. Prior screening was demonstrated in 71 per cent of patients. Colonoscopy was the most commonly used modality. There was a higher percentage of CRC screening at VAMC compared with UVA (80% vs 62%, P < 0.0008). Patients at UVA were more likely screened with colonoscopy, whereas fecal occult blood testing (FOBT) was most common at VAMC (P < 0.0001). Prior CRC screening and cancer stage were inversely related. Ninety-one per cent of patients with benign polyps had been screened prior to diagnosis, compared with 72 per cent of patients with stage I and II cancer and 54 per cent of patients with stage III and IV cancer (P < 0.05). Of patients presenting for surgery, 71 per cent underwent CRC screening. Variability exists in the methods employed for CRC screening. CRC screening facilitates diagnosis at an early stage.

Aged↗

PubMed2005

Primary human hepatocytes in spheroid formation to study hepatitis C infection.

BACKGROUND: Hepatitis C (HCV) is a worldwide health problem, affecting nearly 170 million people. Current models for studying Hepatitis C have focused primarily on the use of poorly permissive cell lines and viral constructs, because of the lack of a suitable animal model or an in vitro system for studying functional infection. As hepatocytes are the primary reservoir for the virus in vivo, we report on a model using primary human hepatocytes cultured in spheroid formation. MATERIALS AND METHODS: The hepatocytes were harvested from uninfected liver resections and cultured as spheroids (that promotes a differentiated phenotype) or monolayers. Spheroids expressed the putative receptors CD81 and human scavenger receptor B1 in a variable pattern throughout the culture period. Samples were inoculated with infectious HCV serum, and HCV RNA was detected using RT-PCR. RNA was detected in the cells and culture medium by 3 days and 5 days after inoculation, respectively. Selection of HVR1 variants occurred in a differential pattern based on culture technique, suggesting that viral selection was dependent on host phenotype. Detection of NS5A by Western blot analysis of infected samples and immunofluorescence for HCV core protein was seen only in infected spheroids. CONCLUSION: The use of spheroid formation to study Hepatitis C is associated with the establishment of HVR1 selection and functional infection. This represents a promising alternative model to study Hepatitis C.

Antigens, CD↗

PubMed2005

Magnetic resonance urography for the assessment of potential renal donors: comparison of the RARE technique with a low-dose gadolinium-enhanced magnetic resonance urography technique in the absence of pharmacological and mechanical intervention.

The aim of this study was to determine whether magnetic resonance urography without pharmacological (diuretic) stimulation and mechanical compression allows conclusive evaluation of the urinary system in potential renal donors. In 28 consecutive patients magnetic resonance urography (MRU) was performed on a 1.5-T system. Two techniques, rapid acquisition with relaxation enhancement (RARE) and a gadolinium (Gd)-enhanced 3D fast low angle shot (FLASH) sequence were compared in the absence of adjunctive measures. Two reviewers assessed image quality, presence of artifacts and completeness of visualization of the collecting systems and ureters. Among the 53 MR urograms, there was no difference in image quality and presence of artifacts between RARE and Gd-MRU. Despite high image quality, visualization of the urinary collecting system was insufficient. Continuous visualization from the collecting system to the distal ureter was demonstrated bilaterally in only 14% of the RARE and 26% of Gd-enhanced MR urograms, respectively. Overall, Gd-enhanced MRU was superior to the RARE technique in displaying the segments of the urinary collecting system, but this difference was not found to be statistically significant. Neither the RARE technique nor the gadolinium-enhanced MRU technique is accurate enough to allow the evaluation of the collecting system and ureters in potential renal donors in the absence of pharmacological intervention and compression.

Adult↗

PubMed2005

MRI for the diagnosis of blunt abdominal trauma: a case report.

Blunt abdominal trauma is a leading cause of trauma related mortality. Currently, the gold standard in the radiographic evaluation of intra-abdominal injury is computed tomography (CT) with iodinated contrast material. However, in the setting of renal failure or a previous anaphylactic reaction to contrast material, radiographic evaluation of the trauma patient may prove difficult. Without contrast material, the sensitivity of CT in the diagnosis of solid organ injury is diminished. We present a case report and literature review of magnetic resonance imaging in the evaluation of blunt abdominal trauma.

Abdominal Injuries↗

PubMed2005

Infected physicians and invasive procedures: safe practice management.

There is currently no public policy that provides guidance concerning whether and when physicians infected with hepatitis B virus (HBV), hepatitis C virus (HCV), and/or human immunodeficiency virus (HIV) can safely perform invasive procedures. A committee of experts in the fields of medicine, law, and biomedical ethics and 1 community member, aided by an advisory board, was established to produce recommendations for policy reform. An extensive literature review was conducted for these 3 infectious diseases, medicine, surgery, epidemiology, law, and bioethics to gather all relevant data. Special recommendations are made regarding the management of physicians who are infected with HIV, HBV, and/or HCV. This policy proposal includes a list of exposure-prone procedures and a decision chart that indicates under what conditions infected physicians can practice beyond the need for disclosure of their serological status.

Decision Making↗

PubMed2005

The training needs and priorities of male and female surgeons and their trainees.

BACKGROUND: Over the past decade, interest in general surgery careers has declined and the number of female medical school graduates has increased. This study was performed to identify the needs of both male and female surgical trainees and to guide design of training programs because attracting medical students to, and maintaining residents in, general surgery training programs can be difficult without a clear understanding of the training needs and priorities of both men and women. We hypothesized that men and women would express similar training priorities, yet have subjectively different experiences. STUDY DESIGN: Medical students, surgical residents, fellows, and fully trained surgeons affiliated with at least one of four major surgical societies were asked to complete a level-specific survey located on the American College of Surgeons Web site. RESULTS: There were 4,308 respondents (76% men). Men and women selected similar reasons for choosing a surgical career and residency program and criteria critical to a successful residency program, with women placing greater emphasis on clerkship experience and faculty diversity. There were no statistically significant differences between the men and women's perceptions of their own training. Although, when asked to evaluate whether certain aspects of training were comparable for male and female residents, women were statistically less likely to agree that their experiences were comparable with those of their male colleagues. CONCLUSIONS: Male and female surgical residents, fellows, and trained surgeons identified almost identical training needs and priorities yet women perceived disparate treatment.

Attitude of Health Personnel↗

PubMed2005

Health-care-associated infections and prevention.

Health-care-associated infections (HAIs) are an important cause of perioperative morbidity and mortality. Currently, one out of every 10 surgical patients develops an HAI. Causes of HAIs vary, but include the transient immunodeficiency associated with surgery,immobility, and the presence of indwelling devices. With rates of antimicrobial resistance increasing, prevention remains the best solution. The investigators review the most frequently encountered health-care-associated infections with an emphasis on preventative strategies. The article addresses issues related to the diagnosis,treatment, and prevention of health-care-related pneumonia,health-care-associated urinary tract infections, and intravascular-catheter-related infections. The article also discusses the utility of hand hygiene policies.

Anti-Bacterial Agents↗

PubMed2005

Nature of gram-negative rod antibiotic resistance during antibiotic rotation.

PURPOSE: The aim of this study was to characterize the evolution of gram-negative antibiotic resistance during a study of empiric antibiotic rotation. METHODS: We showed previously that quarterly rotation of a single antibiotic class is inferior to cycling two antibiotics per quarter for empiric treatment of gram-negative rod (GNR) infections, as evidenced by increased incidence of antibiotic-resistant GNR (rGNR) infections. Resistance patterns were examined by quantifying GNRs resistant to one or more of the following drug classes: Aminoglycosides, cephalosporins, carbapenems, fluoroquinolones, or piperacillin-tazobactam. For all rGNR isolates, the mean number of antibiotic classes to which an organism was resistant was calculated per quarter, as was the number of rGNR species. RESULTS: Single-antibiotic rotation (SAR) was associated with significant increases in the incidence of piperacillin-tazobactam (p < 0.0005) and cephalosporin (p = 0.003) resistance, reaching nearly 25% and 30% of rGNR isolates respectively, most notably during the quarter of designated cephalosporin use (VI). Multi-drug resistance emerged over time; resistant classes/resistant GNR isolates ranged from 1.2 in the dual-antibiotic rotation (DAR) to 1.9 in the SAR period (p = 0.02). Resistance was evident in an increasing number of unique GNR species. On average, 1.3 species were isolated per month in the DAR period and 3.0/month in the SAR period (p = 0.004), but proportionally, no single GNR species became significantly more resistant across time. Compared to only 5.8% in the DAR period, 29% noncompliance was observed in the SAR, with a six-fold increase in the use of nonscheduled empiric antibiotics due to the presence of an organism resistant to the scheduled rotation drug. CONCLUSIONS: A single-antibiotic rotation is associated with increased incidence and heterogeneity of resistant GNR isolates, as well as increased multiple-drug-class resistance. The attenuation of resistance observed in the single-antibiotic rotation may reflect the effect of unintended antibiotic heterogeneity driven by increasing resistance to the antibiotic class recommended for use each quarter. This suggests that reliance on a single antibiotic class for empiric treatment of GNR infection exerts sufficient pressure within the environment to encourage the development of diversified resistance, as well as cross-resistance over antibiotic classes, thus narrowing the availability of effective antibiotic treatment.

Anti-Bacterial Agents↗

PubMed2005

Comparison of fungal and nonfungal infections in a broad-based surgical patient population.

BACKGROUND: Our aim was to compare fungal and nonfungal infections among a diverse surgical patient population. METHODS: Data on all hospital-acquired infectious episodes among surgical intensive care unit and ward patients were collected prospectively over six years at a single university hospital. The relationships between fungal and nonfungal infection and over 100 variables were examined using univariate and multiple logistic regression analysis. RESULTS: During the study period, 3,980 infectious episodes were identified; 554 were associated with fungal infection. Multiple logistic regression analysis demonstrated that markers of severity of acute illness (higher APACHE II scores and white blood cell counts, greater transfusion of cellular blood products, mechanical ventilator dependency, and prior infection) predicted fungal infection, whereas markers of chronic illness (comorbidities) did not independently predict either fungal or nonfungal infection. Patients with fungal infection were treated with more antibiotics for longer periods of time, had prolonged lengths of stay, and more often died compared with nonfungal infection patients. A separate multiple logistic regression analysis demonstrated that both fungal infection and the number of fungal sites of infection independently predicted mortality. Of all fungal isolates, only Candida albicans and Aspergillus spp. independently predicted mortality. CONCLUSIONS: Fungal infections differ significantly in character and outcomes from nonfungal infections among surgical patients.

APACHE↗

PubMed2005

Does the addition of glutamine to enteral feeds affect patient mortality?

OBJECTIVE: Studies have failed to consistently demonstrate improved survival in intensive care unit (ICU) patients receiving immune-modulating nutrient-enhanced enteral feeds when compared with standard enteral feeds. The objective was to study in a prospective fashion the effects of adding glutamine to standard or immune-modulated (supplemented with omega-3 fatty acids, beta-carotene, and amino acids such as glutamine and arginine) tube feeds. DESIGN: Prospective, unblinded study using sequential allocation. SETTING: A university surgical trauma ICU. PATIENTS: All surgical and trauma patients admitted to the surgical trauma ICU at a university hospital over a 3-yr period who were to receive enteral feeds (n = 185). INTERVENTIONS: Sequential assignment to three isocaloric, isonitrogenous diets was performed as follows: standard 1-kcal/mL feeds with added protein (group 1), standard feeds with the addition of 20-40 g/day (0.6 g/kg/day) glutamine (group 2), or an immune-modulated formula with similar addition of glutamine (group 3). The goal for all patients was 25-30 kcal/kg/day and 2 g/kg/day protein. MEASUREMENTS AND MAIN RESULTS: Patients were followed until discharge from the hospital. The primary end point was in-hospital mortality, and multiple secondary end points were recorded. In-hospital mortality for group 1 was 6.3% (four of 64) vs. 16.9% (ten of 59, p = .09) for group 2 and 16.1% (ten of 62, p = .09) for group 3. After controlling for age and severity of illness, the difference in mortality between patients receiving standard tube feeds and all patients receiving glutamine was not significant (p < or = .11). There were no statistically significant differences between the groups for secondary end points. CONCLUSIONS: The addition of glutamine to standard enteral feeds or to an immunomodulatory formula did not improve outcomes. These findings suggest that enteral glutamine should not be routinely administered to patients with surgical critical illness.

APACHE↗

PubMed2005

HCV infection of the transplanted liver: changing CD81 and HVR1 variants immediately after liver transplantation.

The second envelope protein at hypervariable region 1 (HVR1) has been implicated in contributing to hepatitis C virus (HCV)-host cell interactions and CD81 (a multifunctional protein) has been demonstrated to act as a cell surface receptor for HCV and may interact directly with HVR1. The purpose of the current study was to determine if certain HVR1 quasispecies variants more effectively associate with and infect allografts after liver transplantation than other HVR1 variants and whether CD81 receptor expression changes after transplantation. Blood and allograft samples were obtained from the peritransplant period in seven patients. Clones of RT-PCR product were directly sequenced to identify HVR1 quasispecies variants. Explanted liver and serial allograft biopsies in recipients with HCV were examined by immunohistochemistry (IHC) for CD81 expression. Examination of HVR1 sequences demonstrated that only a fraction of the quasispecies variants recovered from each patient's blood sampled immediately prior to transplantation associated with and infected the allografts. Genetic diversity at HVR1 decreased with reperfusion but did not significantly decrease with infection. Expression of CD81 varied during the immediate post-transplant period. In conclusion, HVR1 quasispecies variants differentially associate with, and infect allografts, after liver transplantation. Additionally, allografts express variable amounts of CD81 after transplantation.

Amino Acid Sequence↗