Biomedical subjects

Fabián Jaimes

Publications and source records attributed to Fabián Jaimes.

7 recordsLinked to original sources

PubMed2006

A randomized clinical trial of unfractioned heparin for treatment of sepsis (the HETRASE study): design and rationale [NCT00100308].

INTRODUCTION: Infection promotes coagulation via a large number of molecular and cellular mechanisms, and this procoagulant activity has boosted basic and clinical research using anticoagulant molecules as therapeutic tools in sepsis. Heparin, which is a naturally occurring proteoglycan that acts by reducing thrombin generation and fibrin formation, has not been rigorously tested in a randomized clinical trial. METHODS: Randomized, double-masked, placebo-controlled, single-center clinical trial. Patients are recruited through the emergency room at Hospital Universitario San Vicente de Paul. This is a 650-bed University Hospital in Medellín, Colombia and is a referral center for a region with approximately 3 million habitants. The recruitment process started on July 2005 and will finish on June 2007. Patients aged 18 years or older, males or females, hospitalized with clinically or microbiological confirmed sepsis, have been included. The interventions are unfractioned heparin in low dose continuous infusion (500 units per hour for 7 days) or placebo, additionally to the standard of care for sepsis patients in Colombia. RESULTS: Our primary aims are to estimate the effects of heparin on hospital length of stay and change from baseline Multiple Organ Dysfunction (MOD) score. Secondary objectives are to estimate the effects of heparin on 28-day all-cause mortality, and to estimate the possible effect modification on 28-day all-cause mortality, in subgroups defined by source and site of infection, and baseline values of APACHE II score, MOD score and D-dimer. CONCLUSION: The available literature in animal and human research, and the understanding of the molecular biology regarding inflammation and coagulation, supports a randomized clinical trial for the use of heparin in sepsis. Our study will provide appropriate power to detect differences in valid surrogate outcomes, and it will explore important preliminary data for efficacy regarding the clinical end-point of mortality.

Journal Article↗

PubMed2006

[Anticoagulation and sepsis: the opportunity for a new use of heparin?].

Sepsis is a leading cause of morbidity and mortality worldwide, and the magnitude of the problem seems higher in developing countries. In the last two decades the accepted standard treatment has resulted in only a slight decrease in mortality, and that decrease has been overshadowed by an almost 300% increase in incidence. Recently has been documented the close relationship between infection, inflammation and coagulation in sepsis has been documented; and although clinically overt disseminated intravascular coagulation may occur in only 30% to 50% of septic patients, the activation of the coagulation cascade is an early and common response to the infectious challenge. Moreover most of the molecules involved in the pro-coagulant state that characterizes sepsis are also powerful generators or amplifiers of the inflammatory response. These findings have fostered a comprehensive body of research regarding biological products with anticoagulant activity, as additional therapies for patients with the most severe states of the sepsis syndrome. This review explains the biological and molecular aspects that support the potential use of anticoagulant treatments in sepsis. Furthermore, we analyze the evidence provided by experimental and pre-clinical studies, which suggest the usefulness of heparin as an effective complementary treatment throughout the clinical stages of the disease.

Animals↗

PubMed2005

Comparison between logistic regression and neural networks to predict death in patients with suspected sepsis in the emergency room.

INTRODUCTION: Neural networks are new methodological tools based on nonlinear models. They appear to be better at prediction and classification in biological systems than do traditional strategies such as logistic regression. This paper provides a practical example that contrasts both approaches within the setting of suspected sepsis in the emergency room. METHODS: The study population comprised patients with suspected bacterial infection as their main diagnosis for admission to the emergency room at two University-based hospitals. Mortality within the first 28 days from admission was predicted using logistic regression with the following variables: age, immunosuppressive systemic disease, general systemic disease, Shock Index, temperature, respiratory rate, Glasgow Coma Scale score, leucocyte counts, platelet counts and creatinine. Also, with the same input and output variables, a probabilistic neural network was trained with an adaptive genetic algorithm. The network had three neurone layers: 10 neurones in the input layer, 368 in the hidden layer and two in the output layer. Calibration was measured using the Hosmer-Lemeshow goodness-of-fit test and discrimination was determined using receiver operating characteristic curves. RESULTS: A total of 533 patients were recruited and overall 28-day mortality was 19%. The factors chosen by logistic regression (with their score in parentheses) were as follows: immunosuppressive systemic disease or general systemic disease (2), respiratory rate 24-33 breaths/min (1), respiratory rate > or = 34 breaths/min (3), Glasgow Come Scale score < or = 12 (3), Shock Index > or = 1.5 (2) and temperature < 38 degrees C (2). The network included all variables and there were no significant differences in predictive ability between the approaches. The areas under the receiver operating characteristic curves were 0.7517 and 0.8782 for the logistic model and the neural network, respectively (P = 0.037). CONCLUSION: A predictive model would be an extremely useful tool in the setting of suspected sepsis in the emergency room. It could serve both as a guideline in medical decision-making and as a simple way to select or stratify patients in clinical research. Our proposed model and the specific development method -- either logistic regression or neural networks -- must be evaluated and validated in an independent population.

Adolescent↗

PubMed2005

A literature review of the epidemiology of sepsis in Latin America.

OBJECTIVES: Epidemiological studies from the United States of America and from Europe have shown that sepsis is a widely prevalent syndrome, with either steady or slightly decreasing rates of morbidity and of mortality in recent decades. The objective of this paper is to provide a systematic review regarding the description and characterization of sepsis in Latin America. METHODS: To locate materials on sepsis in Latin America, a comprehensive search strategy was employed with three medical bibliographic databases, using combinations of the terms "sepsis," "septicemia," "bacteremia," "sepsis syndrome," "epidemiology," "incidence," and "prevalence." The materials selected were in English, Spanish, or Portuguese. RESULTS: The titles of more than 1,000 potentially relevant articles were screened, and more than 600 selected abstracts were reviewed in detail. Twenty papers published from 1990 through 2004 were selected and analyzed. The studies described in the 20 articles were extremely heterogeneous in design, population, sample size, end points, and follow-up. The studies did not all apply the same clinical definition for sepsis, thus making it impossible to produce a precise overall estimate of the magnitude of the problem of sepsis in Latin America. CONCLUSIONS: The results of the literature review suggest that the clinical and epidemiological approaches to the problem of sepsis in Latin America have sometimes been inappropriate with respect to research design, study population, and clinical outcome. Further, some data suggest that in terms of both frequency and mortality the situation with sepsis and severe systemic infections may be worse in Latin America than it is in developed countries.

Australia↗

PubMed2004

Predicting bacteremia at the bedside.

Our aim was to develop a clinical prediction rule for detection of bacteremia in a cohort of patients observed prospectively at a reference center in Medellín, Colombia. The significant predictors of bacteremia were an age of >or=30 years (odds ratio [OR], 2.07; 95% confidence interval [CI], 1.19-3.60), a heart rate of >or=90 beats/min (OR, 1.90; 95% CI, 1.13-3.17), a temperature of >or=37.8 degrees C (OR, 2.42; 95% CI, 1.41-4.14), a leukocyte count of >or=12,000 cells/microL (OR, 2.40; 95% CI, 1.41-4.10), use of a central venous catheter (OR, 1.89; 95% CI, 1.02-3.50), and a length of hospitalization of >or=10 days (OR, 2.02; 95% CI, 1.25-3.24). The Hosmer-Lemeshow test revealed a goodness-of-fit of 2.99 (P=.981), and the area under the receiver operating characteristics curve was 0.7186. Simple variables obtained from the clinical history of patients are associated with bloodstream infection in a reproducible fashion and should be instrumental for prioritizing the requests for blood cultures by clinicians.

Adult↗

PubMed2003

The systemic inflammatory response syndrome (SIRS) to identify infected patients in the emergency room.

OBJECTIVE: Evaluation of the usefulness of criteria for systemic inflammatory response syndrome (SIRS) compared with the final diagnosis of infection in patients admitted to the emergency room of two university-based hospitals. DESIGN: Longitudinal cohort study. SETTING: Hospital Universitario San Vicente de Paul and Hospital General de Medellín, Medellín, Colombia. PATIENTS. Seven hundred thirty-four patients with suspected infection as main diagnosis for admittance into the emergency room. MEASUREMENTS AND RESULTS: Sensitivity, specificity, predictive values and likelihood ratios (LR) of SIRS criteria at admission were determined using, as gold standards, the diagnosis at the time of discharge based on clinical history and evolution, and microbiological confirmation of infection. SIRS criteria were met by 503 patients (68.5%); the discharge diagnosis of infection was found in 657 (89.4%) and 276 (37%) had microbiological confirmation. SIRS criteria exhibited a sensitivity of 69%, specificity of 35%, positive predictive value (PPV) of 90%, negative predictive value (NPV) of 12% and positive LR of 1.06. There were no differences between the two gold standards. CONCLUSIONS: The finding of two or more SIRS criteria was of little usefulness for diagnosis of infection. It is necessary to work with new criteria and probably with biological markers, in order to obtain a simple, precise and operative definition of the sepsis phenomenon.

Adult↗

PubMed2002

Lack of microbiological concordance between bone and non-bone specimens in chronic osteomyelitis: an observational study.

BACKGROUND: Prognosis of chronic osteomyelitis depends heavily on proper identification and treatment of the bone-infecting organism. Current knowledge on selecting the best specimen for culture is confusing, and many consider that non-bone specimens are suitable to replace bone cultures. This paper compares the microbiology of non-bone specimens with bone cultures, taking the last as the diagnostic gold standard. METHODS: Retrospective observational analysis of 50 patients with bacterial chronic osteomyelitis in a 750-bed University-based hospital. RESULTS: Concordance between both specimens for all etiologic agents was 28%, for Staphylococcus aureus 38%, and for organisms other than S. aureus 19%. The culture of non-bone specimens to identify the causative organisms in chronic osteomyelitis produced 52% false negatives and 36% false positives when compared against bone cultures. CONCLUSIONS: Diagnosis and therapy of chronic osteomyelitis cannot be guided by cultures of non-bone specimens because their microbiology is substantially different to the microbiology of the bone.

Adolescent↗