Richard P. Wenzel

Bio: Richard P. Wenzel is an academic researcher from Virginia Commonwealth University. The author has contributed to research in topics: Infection control & Bacteremia. The author has an hindex of 103, co-authored 425 publications receiving 44403 citations. Previous affiliations of Richard P. Wenzel include University of Iowa & National Institutes of Health.

Nosocomial Bloodstream Infections in US Hospitals: Analysis of 24,179 Cases from a Prospective Nationwide Surveillance Study

Abstract: Background. Nosocomial bloodstream infections (BSIs) are important causes of morbidity and mortality in the United States. Methods. Data from a nationwide, concurrent surveillance study (Surveillance and Control of Pathogens of Epidemiological Importance [SCOPE]) were used to examine the secular trends in the epidemiology and microbiology of nosocomial BSIs. Results. Our study detected 24,179 cases of nosocomial BSI in 49 US hospitals over a 7-year period from March 1995 through September 2002 (60 cases per 10,000 hospital admissions). Eighty-seven percent of BSIs were monomicrobial. Gram-positive organisms caused 65% of these BSIs, gram-negative organisms caused 25%, and fungi caused 9.5%. The crude mortality rate was 27%. The most-common organisms causing BSIs were coagulasenegative staphylococci (CoNS) (31% of isolates), Staphylococcus aureus (20%), enterococci (9%), and Candida species (9%). The mean interval between admission and infection was 13 days for infection with Escherichia coli, 16 days for S. aureus, 22 days for Candida species and Klebsiella species, 23 days for enterococci, and 26 days for Acinetobacter species. CoNS, Pseudomonas species, Enterobacter species, Serratia species, and Acinetobacter species were more likely to cause infections in patients in intensive care units ( ). In neutropenic patients, infections P ! .001 with Candida species, enterococci, and viridans group streptococci were significantly more common. The proportion of S. aureus isolates with methicillin resistance increased from 22% in 1995 to 57% in 2001 ( , trend P ! .001 analysis). Vancomycin resistance was seen in 2% of Enterococcus faecalis isolates and in 60% of Enterococcus faecium isolates. Conclusion. In this study, one of the largest multicenter studies performed to date, we found that the proportion of nosocomial BSIs due to antibiotic-resistant organisms is increasing in US hospitals.

The Natural History of the Systemic Inflammatory Response Syndrome (SIRS): A Prospective Study

Abstract: Objective. —Define the epidemiology of the four recently classified syndromes describing the biologic response to infection: systemic inflammatory response syndrome (SIRS), sepsis, severe sepsis, and septic shock. Design. —Prospective cohort study with a follow-up of 28 days or until discharge if earlier. Setting. —Three intensive care units and three general wards in a tertiary health care institution. Methods. —Patients were included if they met at least two of the criteria for SIRS: fever or hypothermia, tachycardia, tachypnea, or abnormal white blood cell count. Main Outcomes Measures. —Development of any stage of the biologic response to infection: sepsis, severe sepsis, septic shock, end-organ dysfunction, and death. Results. —During the study period 3708 patients were admitted to the survey units, and 2527 (68%) met the criteria for SIRS. The incidence density rates for SIRS in the surgical, medical, and cardiovascular intensive care units were 857,804, and 542 episodes per 1000 patient-days, respectively, and 671,495, and 320 per 1000 patient-days for the medical, cardiothoracic, and general surgery wards, respectively. Among patients with SIRS, 649 (26%) developed sepsis, 467 (18%) developed severe sepsis, and 110 (4%) developed septic shock. The median interval from SIRS to sepsis was inversely correlated with the number of SIRS criteria (two, three, or all four) that the patients met. As the population of patients progressed from SIRS to septic shock, increasing proportions had adult respiratory distress syndrome, disseminated intravascular coagulation, acute renal failure, and shock. Positive blood cultures were found in 17% of patients with sepsis, in 25% with severe sepsis, and in 69% with septic shock. There were also stepwise increases in mortality rates in the hierarchy from SIRS, sepsis, severe sepsis, and septic shock: 7%, 16%, 20%, and 46%, respectively. Of interest, we also observed equal numbers of patients who appeared to have sepsis, severe sepsis, and septic shock but who had negative cultures. They had been prescribed empirical antibiotics for a median of 3 days. The cause of the systemic inflammatory response in these culture-negative populations is unknown, but they had similar morbidity and mortality rates as the respective culture-positive populations. Conclusions. —This prospective epidemiologic study of SIRS and related conditions provides, to our knowledge, the first evidence of a clinical progression from SIRS to sepsis to severe sepsis and septic shock. ( JAMA . 1995;273:117-123)

Nosocomial Bloodstream Infections in United States Hospitals: A Three-Year Analysis

Abstract: Nosocomial bloodstream infections are important causes of morbidity and mortality. In this study, concurrent surveillance for nosocomial bloodstream infections at 49 hospitals over a 3-year period detected >10,000 infections. Gram-positive organisms accounted for 64% of cases, gram-negative organisms accounted for 27%, and 8% were caused by fungi. The most common organisms were coagulase-negative staphylococci (32%), Staphylococcus aureus (16%), and enterococci (11%). Enterobacter, Serratia, coagulase-negative staphylococci, and Candida were more likely to cause infections in patients in critical care units. In patients with neutropenia, viridans streptococci were significantly more common. Coagulase-negative staphylococci were the most common pathogens on all clinical services except obstetrics, where Escherichia coli was most common. Methicillin resistance was detected in 29% of S. aureus isolates and 80% of coagulase-negative staphylococci. Vancomycin resistance in enterococci was species-dependent-3% of Enterococcus faecalis strains and 50% of Enterococcus faecium isolates displayed resistance. These data may allow clinicians to better target empirical therapy for hospital-acquired cases of bacteremia.

Nosocomial bloodstream infection in critically ill patients. Excess length of stay, extra costs, and attributable mortality.

Abstract: Objective. —To determine the excess length of stay, extra costs, and mortality attributable to nosocomial bloodstream infection in critically ill patients. Design. —Pairwise-matched (1:1) case-control study. Setting. —Surgical intensive care unit (SICU) in a tertiary health care institution. Patients. —All patients admitted in the SICU between July 1,1988, and June 30, 1990, were eligible. Cases were defined as patients with nosocomial bloodstream infection; controls were selected according to matching variables in a stepwise fashion. Methods. —Matching variables were primary diagnosis for admission, age, sex, length of stay before the day of infection in cases, and total number of discharge diagnoses. Matching was successful for 89% of the cohort; 86 matched case-control pairs were studied. Main Outcome Measures. —Crude and attributable mortality, excess length of hospital and SICU stay, and overall costs. Results. —Nosocomial bloodstream infection complicated 2.67 per 100 admissions to the SICU during the study period. The crude mortality rates from cases and controls were 50% and 15%, respectively (P Conclusions. —The attributable mortality from nosocomial bloodstream infection is high in critically ill patients. The infection is associated with a doubling of the SICU stay, an excess length of hospital stay of 24 days in survivors, and a significant economic burden. (JAMA. 1994;271:1598-1601)

Hospital-Acquired Candidemia: The Attributable Mortality and Excess Length of Stay

Abstract: • Between 1977 and 1984, estimates of hospital-acquired bloodstream infections caused byCandidaspecies increased in the United States from 0.5 to 1.5 per 10000 admissions (National Nosocomial Infection Study data). We examined crude and attributable mortality rates and excess length of stay in 88 closely matched pairs of cases and controls with illnesses occurring between July 1983 and December 1986. The crude mortality rates for cases and controls were 57% and 19%, respectively; thus the attributable mortality rate was 38% with a 95% confidence interval of 26% to 49%. The risk ratio was 2.94 with a 95% confidence interval of 1.95 to 4.43. The median length of stay was 48 days for all cases and 40 days for all controls. An analysis of the length of stay for the 34 matched pairs that survived showed a median of 70 days for cases and 40 days for controls.Candidabloodstream infections represented 10% of all nosocomial bloodstream infections in the period studied at our University Hospital; they are associated with a significant medical and economic burden well above that expected of the underlying diseases alone. (Arch Intern Med1988;148:2642-2645)

The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3)

Abstract: Importance Definitions of sepsis and septic shock were last revised in 2001. Considerable advances have since been made into the pathobiology (changes in organ function, morphology, cell biology, biochemistry, immunology, and circulation), management, and epidemiology of sepsis, suggesting the need for reexamination. Objective To evaluate and, as needed, update definitions for sepsis and septic shock. Process A task force (n = 19) with expertise in sepsis pathobiology, clinical trials, and epidemiology was convened by the Society of Critical Care Medicine and the European Society of Intensive Care Medicine. Definitions and clinical criteria were generated through meetings, Delphi processes, analysis of electronic health record databases, and voting, followed by circulation to international professional societies, requesting peer review and endorsement (by 31 societies listed in the Acknowledgment). Key Findings From Evidence Synthesis Limitations of previous definitions included an excessive focus on inflammation, the misleading model that sepsis follows a continuum through severe sepsis to shock, and inadequate specificity and sensitivity of the systemic inflammatory response syndrome (SIRS) criteria. Multiple definitions and terminologies are currently in use for sepsis, septic shock, and organ dysfunction, leading to discrepancies in reported incidence and observed mortality. The task force concluded the term severe sepsis was redundant. Recommendations Sepsis should be defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. For clinical operationalization, organ dysfunction can be represented by an increase in the Sequential [Sepsis-related] Organ Failure Assessment (SOFA) score of 2 points or more, which is associated with an in-hospital mortality greater than 10%. Septic shock should be defined as a subset of sepsis in which particularly profound circulatory, cellular, and metabolic abnormalities are associated with a greater risk of mortality than with sepsis alone. Patients with septic shock can be clinically identified by a vasopressor requirement to maintain a mean arterial pressure of 65 mm Hg or greater and serum lactate level greater than 2 mmol/L (>18 mg/dL) in the absence of hypovolemia. This combination is associated with hospital mortality rates greater than 40%. In out-of-hospital, emergency department, or general hospital ward settings, adult patients with suspected infection can be rapidly identified as being more likely to have poor outcomes typical of sepsis if they have at least 2 of the following clinical criteria that together constitute a new bedside clinical score termed quickSOFA (qSOFA): respiratory rate of 22/min or greater, altered mentation, or systolic blood pressure of 100 mm Hg or less. Conclusions and Relevance These updated definitions and clinical criteria should replace previous definitions, offer greater consistency for epidemiologic studies and clinical trials, and facilitate earlier recognition and more timely management of patients with sepsis or at risk of developing sepsis.

Out of the Crisis

Abstract: According to W. Edwards Deming, American companies require nothing less than a transformation of management style and of governmental relations with industry. In Out of the Crisis, originally published in 1982, Deming offers a theory of management based on his famous 14 Points for Management. Management's failure to plan for the future, he claims, brings about loss of market, which brings about loss of jobs. Management must be judged not only by the quarterly dividend, but by innovative plans to stay in business, protect investment, ensure future dividends, and provide more jobs through improved product and service. In simple, direct language, he explains the principles of management transformation and how to apply them.

Early Goal-Directed Therapy in the Treatment of Severe Sepsis and Septic Shock

Abstract: Background Goal-directed therapy has been used for severe sepsis and septic shock in the intensive care unit. This approach involves adjustments of cardiac preload, afterload, and contractility to balance oxygen delivery with oxygen demand. The purpose of this study was to evaluate the efficacy of early goal-directed therapy before admission to the intensive care unit. Methods We randomly assigned patients who arrived at an urban emergency department with severe sepsis or septic shock to receive either six hours of early goal-directed therapy or standard therapy (as a control) before admission to the intensive care unit. Clinicians who subsequently assumed the care of the patients were blinded to the treatment assignment. In-hospital mortality (the primary efficacy outcome), end points with respect to resuscitation, and Acute Physiology and Chronic Health Evaluation (APACHE II) scores were obtained serially for 72 hours and compared between the study groups. Results Of the 263 enrolled patients, 130 were ...

Epidemiology of severe sepsis in the United States: analysis of incidence, outcome, and associated costs of care.

Abstract: ObjectiveTo determine the incidence, cost, and outcome of severe sepsis in the United States.DesignObservational cohort study.SettingAll nonfederal hospitals (n = 847) in seven U.S. states.PatientsAll patients (n = 192,980) meeting criteria for severe sepsis based on the International Classification