Fredi Alexander Díaz-Quijano

Effect of Lung Recruitment and Titrated Positive End-Expiratory Pressure (PEEP) vs Low PEEP on Mortality in Patients With Acute Respiratory Distress Syndrome: A Randomized Clinical Trial

Importance The effects of recruitment maneuvers and positive end-expiratory pressure (PEEP) titration on clinical outcomes in patients with acute respiratory distress syndrome (ARDS) remain uncertain. Objective To determine if lung recruitment associated with PEEP titration according to the best respiratory-system compliance decreases 28-day mortality of patients with moderate to severe ARDS compared with a conventional low-PEEP strategy. Design, Setting, and Participants Multicenter, randomized trial conducted at 120 intensive care units (ICUs) from 9 countries from November 17, 2011, through April 25, 2017, enrolling adults with moderate to severe ARDS. Interventions An experimental strategy with a lung recruitment maneuver and PEEP titration according to the best respiratory–system compliance (n = 501; experimental group) or a control strategy of low PEEP (n = 509). All patients received volume-assist control mode until weaning. Main Outcomes and Measures The primary outcome was all-cause mortality until 28 days. Secondary outcomes were length of ICU and hospital stay; ventilator-free days through day 28; pneumothorax requiring drainage within 7 days; barotrauma within 7 days; and ICU, in-hospital, and 6-month mortality. Results A total of 1010 patients (37.5% female; mean [SD] age, 50.9 [17.4] years) were enrolled and followed up. At 28 days, 277 of 501 patients (55.3%) in the experimental group and 251 of 509 patients (49.3%) in the control group had died (hazard ratio [HR], 1.20; 95% CI, 1.01 to 1.42; P = .041). Compared with the control group, the experimental group strategy increased 6-month mortality (65.3% vs 59.9%; HR, 1.18; 95% CI, 1.01 to 1.38; P = .04), decreased the number of mean ventilator-free days (5.3 vs 6.4; difference, −1.1; 95% CI, −2.1 to −0.1; P = .03), increased the risk of pneumothorax requiring drainage (3.2% vs 1.2%; difference, 2.0%; 95% CI, 0.0% to 4.0%; P = .03), and the risk of barotrauma (5.6% vs 1.6%; difference, 4.0%; 95% CI, 1.5% to 6.5%; P = .001). There were no significant differences in the length of ICU stay, length of hospital stay, ICU mortality, and in-hospital mortality. Conclusions and Relevance In patients with moderate to severe ARDS, a strategy with lung recruitment and titrated PEEP compared with low PEEP increased 28-day all-cause mortality. These findings do not support the routine use of lung recruitment maneuver and PEEP titration in these patients. Trial Registration clinicaltrials.gov Identifier: NCT01374022

A simple method for estimating relative risk using logistic regression.

BackgroundOdds ratios (OR) significantly overestimate associations between risk factors and common outcomes. The estimation of relative risks (RR) or prevalence ratios (PR) has represented a statistical challenge in multivariate analysis and, furthermore, some researchers do not have access to the available methods. Objective: To propose and evaluate a new method for estimating RR and PR by logistic regression.MethodsA provisional database was designed in which events were duplicated but identified as non-events. After, a logistic regression was performed and effect measures were calculated, which were considered RR estimations. This method was compared with binomial regression, Cox regression with robust variance and ordinary logistic regression in analyses with three outcomes of different frequencies.ResultsORs estimated by ordinary logistic regression progressively overestimated RRs as the outcome frequency increased. RRs estimated by Cox regression and the method proposed in this article were similar to those estimated by binomial regression for every outcome. However, confidence intervals were wider with the proposed method.ConclusionThis simple tool could be useful for calculating the effect of risk factors and the impact of health interventions in developing countries when other statistical strategies are not available.

Factors Associated with Dengue Mortality in Latin America and the Caribbean, 1995–2009: An Ecological Study

In this study, we aimed to estimate the effect that environmental, demographic, and socioeconomic factors have on dengue mortality in Latin America and the Caribbean. To that end, we conducted an observational ecological study, analyzing data collected between 1995 and 2009. Dengue mortality rates were highest in the Caribbean (Spanish-speaking and non-Spanish-speaking). Multivariate analysis through Poisson regression revealed that the following factors were independently associated with dengue mortality: time since identification of endemicity (adjusted rate ratio [aRR] = 3.2 [for each 10 years]); annual rainfall (aRR = 1.5 [for each 10(3) L/m(2)]); population density (aRR = 2.1 and 3.2 for 20-120 inhabitants/km(2) and > 120 inhabitants/km(2), respectively); Human Development Index > 0.83 (aRR = 0.4); and circulation of the dengue 2 serotype (aRR = 1.7). These results highlight the important role that environmental, demographic, socioeconomic, and biological factors have played in increasing the severity of dengue in recent decades.

Dificultad para el diagnóstico clínico temprano del dengue en un área endémica y su impacto sobre el manejo médico inicial

BACKGROUND Early detection of dengue could help to prevent its complications. The usefulness of clinical criteria for diagnosis of the disease must be ascertained. AIMS To assess the correlation between laboratory and clinical diagnosis of dengue, done during the first consultation in the emergency room. To estimate the impact of clinical diagnosis on the initial medical treatment. PATIENTS AND METHODS Patients older than 5 years with an acute febrile syndrome that consulted during the first 72 hours of disease, during 2004, at an emergency room in Bucaramanga, Colombia, were studied. Symptoms and the clinical diagnosis of the initial evaluation were registered. Paired serum samples for dengue specific ELISA-IgM test and viral isolation were obtained. The association of the initial clinical diagnosis with early symptoms, initial medical treatment and laboratory diagnosis was evaluated. RESULTS One hundred sixty eight patients were enrolled (54 with confirmed dengue infection). Clinical diagnosis of dengue was associated to a higher request of complete blood counts (p = 0.01) and greater use of intravenous fluids (p = 0.02). However, clinical diagnosis was not correlated with the laboratory diagnosis (p = 0.15). The percentage of agreement was less than would be expected by chance (Kappa = -0.1). Headache was associated to the initial clinical diagnosis of dengue (p = 0.03), and only metrorrhagia was associated with confirmed dengue infection (p = 0.04). CONCLUSIONS The early clinical suspicion of dengue has a low concordance with the laboratory confirmation of the disease.

Complicaciones asociadas a la trombocitopenia profunda en pacientes con dengue

Patients with clinical andserologic (positive IgM) diagnosis of dengue, consulting at hospitals located in Santander,Colombia, during the period 1993-1998, were studied. Clinical findings and laboratory tests(including hematocrit and platelets counts) were registered. The association between severethrombocytopenia and the presence of complications, such as hemorrhagic manifestations(positive tourniquet test, petechiae, ecchymoses, bleeding from gums, epistaxis, hematemesis,hematuria and metrorrhagia) and signs of plasma leakage (pleural effusions andhaemoconcentration), were evaluated using a univariate and multivariate analysis.

Predictors of spontaneous bleeding in patients with acute febrile syndrome from a dengue endemic area

BACKGROUND Spontaneous bleeding is a common complication of dengue and is associated with an increased mortality. OBJECTIVE To evaluate early clinical manifestations and simple laboratory tests as predictors of spontaneous hemorrhage in patients with forms of acute febrile syndrome (AFS) such as dengue from an endemic area. STUDY DESIGN A prospective cohort study was performed including 729 non-bleeding AFS patients who were enrolled during the first 4 days of disease. Basal evaluation included anamnesis, physical examination and complete blood cell count. Follow-up was extended at least until the sixth day of disease. Dengue infection was studied with paired serologic tests and viral isolation. Potential predictors of spontaneous bleeding were evaluated with bivariate and multivariate analysis. RESULTS Incidence of outcome was not significantly different between the dengue group and those with non-dengue AFS. The tourniquet test was not associated with outcome (p=0.38). In a binomial regression model, the following variables were associated with outcome: age between 12 and 45 years (RR=2.22; 95% CI: 1.25-3.94), rash (RR=1.66; 95% CI: 1.25-2.2), vomiting (RR=1.46; 95% CI: 1.16-1.83), temperature >38 degrees C (RR=2.63; 95% CI: 1.6-4.33), leukocyte count <4500/microL (RR=1.87; 95% CI: 1.19-2.96), and platelet count <90.000/microL (RR=1.8; 95% CI: 1.1-2.94). With these variables a risk score was formulated that showed an area under ROC curve of 70.5% (95% CI: 64.9-76.2) to predict spontaneous bleeding. The score was useful for predicting bleeding in both dengue and non-dengue AFS groups. CONCLUSION Some variables evaluated in the first days of disease helped to predict the risk of spontaneous bleeding in patients with dengue and non-dengue AFS.

Indicadores tempranos de infección por dengue en niños

OBJECTIVE: To identify clinical manifestations and laboratory findings useful for the early diagnosis of dengue in children. MATERIALS AND METHODS: We prospectively evaluated 125 children (aged 5 to 12 years old) with acute febrile syndrome with no apparent etiology. Paired serologic tests and/or viral culture were performed and dengue infection was confirmed in 40 patients and ruled out in 68 (17 indefinite cases). Early clinical manifestations (within the first 4 days of the disease) in the groups with dengue and other causes of febrile syndrome were compared. Independent indicators of dengue were determined in a multivariate logistic regression analysis. RESULTS: When clinical manifestations and complete blood count were considered, the independent indicators of dengue were: absence of nasal discharge, facial flushing, and leukocyte count 14 seconds, and partial thromboplastin time > 29 seconds. Two of these findings suggested a diagnosis of dengue with a sensitivity of 90 % and a specificity of 52.9 %. With at least 3 findings, specificity increased to 89.7 % and sensitivity decreased to 50 %. The presence of the four components of this latter model shows a specificity of 100 %. CONCLUSIONS: Some clinical manifestations and simple laboratory tests could aid the early detection of dengue infection in children.

Burden of chikungunya in Latin American countries: estimates of disability-adjusted life-years (DALY) lost in the 2014 epidemic.

El Salvador 135 383 61 031 67 867 23 890 26 566 376.78 418.99 Puerto Rico 28 619 12 901 14 347 5050 5616 148.23 164.83 Colombia 83 832 37 791 42 025 14 793 16 450 30.61 34.04 Guatemala 22 057 9943 11 057 3892 4328 25.16 27.98 Venezuela 37 015 16 686 18 556 6532 7263 21.48 23.89 Nicaragua 3556 1603 1783 627 698 10.32 11.48 Honduras 4086 1842 2048 721 802 8.90 9.90 Costa Rica 238 107 119 42 47 0.86 0.96 Brazil 305

Sex differences in cardiac autonomic function of depressed young adults

BACKGROUND Cardiac autonomic dysfunction has been proposed as an important contributing factor to the increased cardiovascular risk observed in major depression (MDD). However, the evidence regarding alterations in heart rate variability (HRV) in otherwise healthy depressed subjects has been inconclusive. METHODS A case-control study in 50 treatment-naïve young adults with a first MDD episode without comorbid psychiatric disorders and 50 healthy control subjects was conducted. Time- and frequency-domain indexes of HRV were determined at baseline supine and after 5-min of orthostatic stress at 60°. RESULTS There were no significant differences in the time- or frequency-domain variables of HRV between depressed patients and controls. However, a random-effect ANOVA model showed that during orthostatic stress depressed men had a reduced HRV and decreased parasympathetic activity compared to control subjects, while no differences were found between depressed women and controls. CONCLUSION These results suggest a sex-dependent relationship between major depression and cardiac autonomic dysfunction and provide one potential explanation for sex differences in the association of depressive symptoms with cardiovascular morbidity.

Pluviosidad como Predictor de Consulta por Síndrome Febril Agudo en un Área Endémica de Dengue

Objetivo Describir los patrones de consulta por SFA asociado al dengue y evaluar su asociacion con la pluviosidad. Metodos En dos clinicas, durante un periodo de 7 meses (de marzo a septiembre) se identificaron 318 casos de SFA indiferenciado que se incluyeron en un seguimiento clinico sistematico. El 31 % (81/281) fueron IgM positivos para dengue. Se evaluo la pluviosidad (litros/metro cuadrado por dia) previa como variable explicatoria del patron de consultas. Resultados Los meses con mas casos de SFA fueron junio, julio y septiembre. Los casos de dengue solo fueron significativamente mas frecuentes en julio. Al evaluar los patrones de pluviosidad de las semanas anteriores, la consulta por SFA estuvo asociada con la pluviosidad promedio registrada 5 semanas antes y esta asociacion fue independiente de la institucion y del mes (Razon de tasas de incidencia ajustada: RTI=1,04; IC95 % 1-1,08; p=0,045). Por otra parte, un promedio de la pluviosidad de 5 semanas consecutivas fue un predictor independiente de consulta por dengue, 4 semanas despues (RTI=1,6; IC95 % 1,15-2,22; p=0.006). Se evidencio una relacion lineal entre la pluviosidad y las consultas por dengue: pluviosidad (promedio de 5 semanas) x 0,72 (IC95 % 0,60-0,84; p<0,001)=casos por cada 100 000 habitantes en una semana (4 semanas despues). Conclusiones La pluviosidad podria predecir el patron de consulta por dengue en una region endemica.