Showing papers by "Avery B. Nathens published in 2003"

Guidelines for the Selection of Anti-infective Agents for Complicated Intra-abdominal Infections

Abstract: Joseph S. Solomkin, John E. Mazuski, Ellen J. Baron, Robert G. Sawyer, Avery B. Nathens, Joseph T. DiPiro, Timothy Buchman, E. Patchen Dellinger, John Jernigan, Sherwood Gorbach, Anthony W. Chow, and John Bartlett Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio; Department of Surgery, Washington University School of Medicine, St. Louis, Missouri; Department of Microbiology, Stanford University School of Medicine, Palo Alto, California; Department of Surgery, University of Virginia, Charlottesville; Department of Surgery, University of Washington, Seattle; University of Georgia College of Pharmacy, Department of Surgery, Medical College of Georgia, Augusta, and Centers for Disease Control and Prevention, Atlanta; Department of Medicine, Tufts University School of Medicine, Boston, Massachusetts; Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland; and Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada

Randomized, Prospective Trial of Antioxidant Supplementation in Critically Ill Surgical Patients

Abstract: OBJECTIVE: To determine the effectiveness of early, routine antioxidant supplementation using α-tocopherol and ascorbic acid in reducing the rate of pulmonary morbidity and organ dysfunction in critically ill surgical patients. SUMMARY BACKGROUND DATA: Oxidative stress has been associated with the development of the acute respiratory distress syndrome (ARDS) and organ failure through direct tissue injury and activation of genes integral to the inflammatory response. In addition, depletion of endogenous antioxidants has been associated with an increased risk of nosocomial infections. The authors postulated that antioxidant supplementation in critically ill surgical patients may reduce the incidence of ARDS, pneumonia, and organ dysfunction. METHODS: This randomized, prospective study was conducted to compare outcomes in patients receiving antioxidant supplementation (α-tocopherol and ascorbate) vs those receiving standard care. The primary endpoint for analysis was pulmonary morbidity (a composite measure ...

Renal injury and operative management in the United States: results of a population-based study.

Abstract: Background: To evaluate the extent to which nonoperative renal trauma management has been adopted, we determined the incidence of renal injury and the rate of operative management across the United States. Methods: International Classification of Diseases, Ninth Revision diagnosis and procedure codes identified patients with renal injuries in an 18-state administrative database representing 62% of the U.S. population. Results: Of 523,870 patients hospitalized for trauma in 1997 or 1998, 6,231 (1.2%) had renal injuries (4.89 per 100,000 population). Sixty-four percent of patients with injuries that were classified had contusions/hematomas, 263% had lacerations, 5.3% had parenchymal disruption, and 4% had vascular injuries. Eleven percent of renal trauma patients required surgical management of their kidney injuries, of whom 61%, or 7% of patients with renal injuries overall, underwent nephrectomy. Injury Severity Score, mechanism, and renal injury severity were independent predictors of nephrectomy. Conclusion: The nephrectomy rate in community and academic centers reflects renal and global injury severity. Prospective trials are indicated to determine whether, in the traumatized patient with severe kidney injury, renal preservation could lead to improved outcomes compared with nephrectomy.

The effect of interfacility transfer on outcome in an urban trauma system.

Abstract: Background Transporting all trauma patients to regional trauma centers is inefficient; however, the bypass of nearer, nondesignated hospitals in deference to regional trauma centers decreases mortality in the severely injured. One approach to improving efficiency is to allow the initial assessment of selected patients at lower level (Level III/IV) designated centers. We set out to evaluate whether patients initially assessed at these centers and then transferred to a Level I facility were adversely affected by delays to definitive care. Methods This is a retrospective cohort study in which the primary exposure being evaluated is initial assessment at a Level III or IV trauma center before transport to a Level I center in an urban setting. The outcomes in this transfer cohort were compared with outcomes in patients transported directly from the scene to a Level I center (direct cohort). The outcomes of interest were mortality, length of stay, and hospital charges. Multivariate analyses were used to adjust for differences in baseline characteristics across these two cohorts. Results Crude length of stay was comparable, whereas mortality was lower and charges were 40% higher in the transfer cohort (n = 281) compared with the direct cohort (n = 4,439). After adjusting for confounders, mortality and length of stay were similar and total charges were significantly greater in the transferred patients. Conclusion Interfacility transfers in a mature urban trauma system do not appear to impact on clinical outcome. However, transfer patients use significantly greater resources as measured by hospital charges. This effect is likely because of the nature of their injuries or, alternatively, delays in reaching definitive care.

Risk factors for severe sepsis in secondary peritonitis.

Abstract: Background: The incidence and risk factors for severe sepsis (SS, organ failure associated with infection) in the context of peritonitis are not well established; thus, it is not clear which patien...

Management of the injured patient: Identification of research topics for systematic review using the delphi technique

Abstract: Background Systematic reviews of controlled clinical trials in the form of meta-analyses can serve as an important guide to direct clinical practice. This study identifies the most important research questions pertaining to the acute care of the injured patient using a Web-based Delphi technique to achieve consensus of expert opinion. Methods Experts in trauma care from the United States and Canada (n = 68) were asked to generate structured research questions and were then required to rank these questions in order of importance and estimate the amount of research currently published. Results The questions ranking in the highest tertile are presented along with an estimate of their importance and the amount of research published using an ordinal scale. Only 9 of 16 (56%) questions had some or a substantial amount of research available on which to perform a systematic review. Conclusion This study identifies the areas of trauma care in which research efforts might best be directed. In the absence of sufficient data for systematic reviews, these research topics represent important areas for the design and implementation of clinical trials.

Patient outcomes in academic medical centers: Influence of fellowship programs and in-house on-call attending surgeon

Abstract: Background There are very few data on characteristics or policies that improve patient outcomes in academic medical institutions. We were interested in 2 such policies or characteristics that are commonly implemented in academic centers: an in-house on-call attending physician policy and the existence of postgraduate medical education. Hypothesis An in-house attending surgeon on-call policy and the presence of trauma and critical care fellowship programs improve outcomes of critically injured patients. Design Multicenter cohort study. Two cohorts were analyzed: blunt trauma (n = 601; mortality, 16.0%) and penetrating abdominal trauma (n = 503; mortality, 7.5%). Setting Thirty-one academic level I trauma centers, 10 (32.3%) with in-house on-call policy and 11 (35.5%) with fellowship programs. Main Outcome Measures Mortality, hospital length of stay, and intensive care unit length of stay. Results In-house on-call surgeon policy had no impact on mortality or length of hospital or intensive care unit stay for either the blunt or penetrating trauma cohort. However, the presence of fellowship programs was associated with a significant decrease in blunt trauma mortality (odds ratio, 0.4; 95% confidence interval [CI], 0.1-0.8) and a decrease in length of intensive care unit stay (mean difference, 4.7 days; 95% CI, 0.6-8.8 days) and hospital stay (mean difference, 3.2 days; 95% CI, 0.6-5.9 days). There were no significant effects of fellowship programs on penetrating trauma outcomes. Conclusions An in-house on-call attending surgeon policy is not associated with improved outcomes. In contrast, presence of a trauma and surgical critical care fellowship program, a potential surrogate marker for an institution that is committed to this specialty interest, is associated with improved outcomes for critically injured patients. An investment in advanced postgraduate medical education has potential benefits in patient care and outcomes.

Mitogen-activated protein kinases in the intensive care unit: prognostic potential.

Abstract: Multiple organ dysfunction syndrome (MODS) is the predominant cause of late death in patients requiring intensive care. Most consider it the pathologic sequela of an excessive host inflammatory response. The failure of current therapeutic interventions focused on the host’s immunoinflammatory response to affect the outcome of MODS stems, in part, from an incomplete understanding of the complex underlying pathophysiology and an inability to identify early the patients at greatest risk for development of MODS. 1 In the severely injured patient, our ability to predict many important outcomes is limited. Current scoring systems, such as the Acute Physiology and Chronic Health Evaluation II (APACHE II) score, use population-based analyses and require the acquisition of many variables to compute a mathematical model to derive a numerical score indicative of outcome. 2–10 These scores define the net physiologic state of a heterogeneous population and, while valuable in estimating overall population mortality, correlate poorly with other important morbidity endpoints. Moreover, even a score associated with a high incidence of death frequently fails to identify the patient early enough so that potentially effective interventions may be implemented before the onset of an irreversible pathologic sequence. Regardless of the initiating sequence, an aberrant immunoinflammatory response is thought to underlie the pathophysiology of ischemia/reperfusion states, the systemic inflammatory response syndrome (SIRS), septic shock, and MODS. Identification of various components of these inflammatory states has generated a series of investigations to establish a potential association between the plasma concentrations of inflammatory products and patient outcome, specifically mortality. While the results are variable, several trials have demonstrated an association between the concentrations of certain inflammatory mediators and mortality. 1 Consequently, numerous clinical trials have been conducted employing selective anticytokine or antimediator compounds. While many of these agents have been proven effective in controlled animal models, they have failed to alter outcome when applied in the clinical arena. 1,11–18 Many of the implicated inflammatory mediators are regulated by intracellular signaling cascades involving the mitogen-activated protein kinases (MAPK). 19–24 One prominent member, p38, mediates the signal transduction induced by many environmental stresses, such as endotoxin and osmotic stress. While its activation is required for the production of such potent cytokines as tumor necrosis factor-alpha (TNF-α) and interleukin 8, p38 also participates in the reprogramming of inflammatory cells, including platelet-activating factor-induced “priming” of peripheral blood mononuclear cells. 19,24,25 Thus, the activation status of critical early signal transduction pathways, such as p38, might permit characterization of the host stress state, thereby enabling early identification of patients at risk for developing an aberrant host inflammatory response and subsequent MODS. Such a diagnostic tool would give clinicians the opportunity to institute and test potential therapeutic interventions. In this study we investigate the activation status of p38 in cells obtained by bronchoalveolar lavage from critically ill trauma patients in an attempt to identify the patients at greatest risk for progression of MODS.

Antibiotics as an Adjunct to Source Control: Revised Surgical Infection Society Guidelines for Antimicrobial Therapy of Intra-abdominal Infections

Abstract: • Antimicrobial therapy is an adjunct to primary source control procedures in treating patients with intra-abdominal infections. • Therapeutic antimicrobials (those given for longer than 24 h) are required only for patients with established intra-abdominal infections. Patients with limited exposure to contamination from a perforated viscus and those who have a removable focus of inflammation should be treated with prophylactic antimicrobials only (those given for less than 24 h). • Therapeutic antimicrobials for intra-abdominal infections should generally be limited to no more than 5–7 days. Ongoing clinical evidence of infection should prompt a search for a new or recurrent infection rather than arbitrary prolongation of antimicrobial therapy with new or different agents. • Antimicrobial regimens for intra-abdominal infections should cover common aerobic and anaerobic enteric flora. A number of different regimens are available, but the choice of antimicrobials for most patients with community-acquired infections should be dictated primarily by considerations of cost, convenience, and potential toxicity. • Patients at high risk for therapeutic failure include those with preexisting physiological compromise and those with difficult-to-treat organisms, which many times have been acquired in the hospital. Antimicrobial therapy may need to be intensified in some of these patients to cover resistant Gram-negative aerobic organisms, enterococci, and yeast.