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BACKGROUND: Vascular leakage is a major feature of acute respiratory distress syndrome (ARDS). We aimed to evaluate the efficacy of FX06, a drug under development that stabilizes interendothelial cell junctions, at reducing vascular leakage during SARS-CoV-2-induced ARDS. METHODS: This multicenter, double-blinded, randomized trial included adults with COVID-19-associated ARDS who had received invasive mechanical ventilation for < 5 days and were randomized to receive either intravenous FX06 (400 mg/d, for 5 days) or its vehicle as placebo. The primary endpoint was the lowering-from day 1 to day 7-of the transpulmonary thermodilution-derived extravascular lung-water index (EVLWi). RESULTS: Twenty-five patients were randomized to receive FX06 and 24 the placebo. Although EVLWi was elevated at baseline (median [IQR] 15.6 mL/kg [13.5; 18.5]), its declines from day 1 to day 7 were comparable for FX06 recipients and controls (respectively, - 1.9 [- 3.3; - 0.5] vs. - 0.8 [- 5.5; - 1.1] mL/kg; estimated effect - 0.8 [- 3.1; + 2.4], p = 0.51). Cardiac indexes, pulmonary vascular permeability indexes, and fluid balances were also comparable, as were PaO2/FiO2 ratios and durations of mechanical ventilation. Adverse event rates were similar for the 2 groups, although more FX06 recipients developed ventilator-associated pneumonia (16/25 (64%) vs. 6/24 (24%), p = 0.009). CONCLUSIONS: In this unique-dosing-regimen study, FX06 did not lower SARS-CoV-2-induced pulmonary vascular leakage. Future investigations will need to evaluate its efficacy at earlier times during the disease or using other regimens. Trial registration NCT04618042. Registered 5 November 2020.
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COVID-19 , Síndrome de Dificultad Respiratoria , Adulto , Humanos , COVID-19/complicaciones , SARS-CoV-2 , Síndrome de Dificultad Respiratoria/terapia , Administración Intravenosa , Permeabilidad CapilarRESUMEN
Introduction: Acute kidney injury (AKI) is frequently observed in patients with COVID-19 admitted to intensive care units (ICUs). Observational studies suggest that cardiovascular comorbidities and mechanical ventilation (MV) are the most important risk factors for AKI. However, no studies have investigated the renal impact of longitudinal covariates such as drug treatments, biological variations, and/or MV parameters. Methods: We performed a monocentric, prospective, longitudinal analysis to identify the dynamic risk factors for AKI in ICU patients with severe COVID-19. Results: Seventy-seven patients were included in our study (median age: 63 [interquartile range, IQR: 53-73] years; 58 (75%) men). Acute kidney injury was detected in 28 (36.3%) patients and occurred at a median time of 3 [IQR: 2-6] days after ICU admission. Multivariate Cox cause-specific time-dependent analysis identified a history of hypertension (cause-specific hazard (CSH) = 2.46 [95% confidence interval, CI: 1.04-5.84]; P = .04), a high hemodynamic Sequential Organ Failure Assessment score (CSH = 1.63 [95% CI: 1.23-2.16]; P < .001), and elevated Paco2 (CSH = 1.2 [95%CI: 1.04-1.39] per 5 mm Hg increase in Pco2; P = .02) as independent risk factors for AKI. Concerning the MV parameters, positive end-expiratory pressure (CSH = 1.11 [95% CI: 1.01-1.23] per 1 cm H2O increase; P = .04) and the use of neuromuscular blockade (CSH = 2.96 [95% CI: 1.22-7.18]; P = .02) were associated with renal outcome only in univariate analysis but not after adjustment. Conclusion: Acute kidney injury is frequent in patients with severe COVID-19 and is associated with a history of hypertension, the presence of hemodynamic failure, and increased Pco2. Further studies are necessary to evaluate the impact of hypercapnia on increasing the effects of ischemia, particularly in the most at-risk vascular situations.
Introduction: L'insuffisance rénale aiguë (IRA) est fréquemment observée chez les patients atteints de COVID-19 admis dans les unités de soins intensifs (USI). Des études observationnelles suggèrent que les comorbidités cardiovasculaires et la ventilation mécanique (VM) seraient les plus importants facteurs de risque de l'IRA. Aucune étude n'a cependant examiné l'impact sur la fonction rénale de covariables longitudinales telles que les traitements médicamenteux, les variations biologiques et/ou les paramètres de la VM. Méthodologie: Nous avons procédé à une analyse prospective et longitudinale dans un seul centre hospitalier afin d'identifier les facteurs de risque dynamiques de l'IRA chez les patients hospitalisés aux USI en raison d'une forme grave de la COVID-19. Résultats: Soixante-dix-sept patients ont été inclus dans notre étude (75 % d'hommes [n=58]; âge médian: 63 ans [ÉIQ: 53-73]). L'IRA a été détectée chez 28 patients (36,3 %) et est survenue dans un délai médian de 3 jours (ÉIQ: 2-6 jours) après l'admission à l'USI. Une analyse de Cox multivariée, spécifique à la cause et tenant compte du temps, a permis de dégager les éléments suivants comme étant des facteurs de risque indépendants pour l'IRA: des antécédents d'hypertension (probabilité par cause [PPC]=2,46 [IC 95 %: 1,04-5,84]; p=0,04), un score SOFA hémodynamique élevé (PPC=1,63 [IC 95 %: 1,23-2,16]; p<0,001) et une concentration élevée de PaCO2 (PPC=1,2 [IC 95 %: 1,04-1,39] pour chaque augmentation de 5 mmHg de pCO2; p = 0,02). En ce qui concerne les paramètres de la VM, une pression expiratoire positive (PPC=1,11 [IC 95 %: 1,01-1,23] pour chaque augmentation de 1 cm H2O; p = 0,04) et l'utilisation d'un bloc neuromusculaire (PPC=2,96 [IC 95 %: 1,22-7,18]; p=0,02) ont été associés à l'IRA dans l'analyse univariée seulement, et non après ajustement. Conclusion: L'IRA est fréquente chez les patients atteints d'une forme grave de COVID-19 et elle est associé à des antécédents d'hypertension, à la présence d'une instabilité hémodynamique et à une augmentation de la pCO2. D'autres études sont nécessaires pour évaluer l'impact de l'hypercapnie sur l'augmentation des effets de l'ischémie, en particulier dans les situations vasculaires les plus à risque.
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Cateterismo/métodos , Catéteres , Falla de Equipo , Adulto , Anciano , Arterias , Humanos , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
OBJECTIVES: Providing appropriate training of procedural skills to residents while ensuring patient safety through trainee supervision is a difficult and constant challenge. We sought to determine how effective and safe procedural skill acquisition is in French ICUs and to identify failure and complication risk factors. DESIGN: Multicenter prospective observational study. Invasive procedures performed by residents were recorded during two consecutive semesters. SETTING: Eighty-four residents. SUBJECTS: Eighty-four residents. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: Number of invasive procedures performed, failure and complication rates, supervision, and assistance provided. Five thousand six hundred seventeen procedures were prospectively studied: 1,007 tracheal intubations, 1,272 arterial and 2,586 central venous catheter insertions, 457 fiberoptic bronchoscopies, and 295 chest tube insertions. During the semesters, residents performed a median of 10 intubations, 14 arterial catheter insertions, and 26 central venous catheter insertions. Complication rates were low, similar to those in the literature: 8.6% desaturation and 7.4% esophageal placement during intubation; 0.4% and 2.3% pneumothorax with jugular and subclavian central venous catheter insertions, respectively. We identified risk factors for failure and complications. Higher rates of failure and complications for intubation were associated with residents with no or little previous experience (p < 0.001); failure of internal jugular vein catheterization was associated with left-side insertion (p = 0.005) and absence of mechanical ventilation (p = 0.007). Supervision and assistance were more frequent at the beginning of the semester and for intubation and chest tube insertion. Finally, residents had less access to fiberoptic bronchoscopy and chest tube insertion. CONCLUSION: Procedural skills acquisition by residents in the ICU appears feasible and safe with complication rates comparable to what has previously been reported. We identified specific procedures and situations associated with higher failure and complication rates that could require proactive training. Questions still remain regarding minimal numbers of procedures to attain competence and how best to provide procedural training.
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Competencia Clínica , Capacitación en Servicio/organización & administración , Unidades de Cuidados Intensivos/organización & administración , Internado y Residencia/organización & administración , Adulto , Cateterismo Venoso Central/efectos adversos , Cateterismo Venoso Central/métodos , Tubos Torácicos/efectos adversos , Femenino , Francia , Humanos , Intubación Intratraqueal/efectos adversos , Intubación Intratraqueal/métodos , Masculino , Estudios Prospectivos , Factores de Riesgo , Factores de TiempoRESUMEN
RATIONALE: Ventilator-associated pneumonia (VAP) causes substantial morbidity and mortality. The influence of subglottic secretion drainage (SSD) in preventing VAP remains controversial. OBJECTIVES: To determine whether SSD reduces the overall incidence of microbiologically confirmed VAP. METHODS: Randomized controlled clinical trial conducted at four French centers. A total of 333 adult patients intubated with a tracheal tube allowing drainage of subglottic secretions and expected to require mechanical ventilation for ≥48 hours was included. Patients were randomly assigned to undergo intermittent SSD (n = 169) or not (n = 164). MEASUREMENTS AND MAIN RESULTS: Primary outcome was the overall incidence of VAP based on quantitative culture of distal pulmonary samplings performed after each clinical suspicion. Other outcomes included incidence of early- and late-onset VAP, duration of mechanical ventilation, and hospital mortality. Microbiologically confirmed VAP occurred in 67 patients, 25 of 169 (14.8%) in the SSD group and 42 of 164 (25.6%) in the control group (P = 0.02), yielding a relative risk reduction of 42.2% (95% confidential interval, 10.4-63.1%). Using the Day 5 threshold, the beneficial effect of SSD in reducing VAP was observed in both early-onset VAP (2 of 169 [1.2%] patients undergoing SSD vs. 10 of 164 [6.1%] control patients; P = 0.02) and late-onset VAP (23 of 126 [18.6%] patients undergoing SSD vs. 32 of 97 [33.0%] control patients; P = 0.01). VAP was clinically suspected at least once in 51 of 169 (30.2%) patients undergoing SSD and 60 of 164 (36.6%) control patients (P = 0.25). No significant between-group differences were observed in duration of mechanical ventilation and hospital mortality. CONCLUSIONS: Subglottic secretion drainage during mechanical ventilation results in a significant reduction in VAP, including late-onset VAP. Clinical trial registered with www.clinicaltrials.gov (NCT00219661).
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Drenaje/métodos , Glotis/metabolismo , Intubación Intratraqueal/instrumentación , Neumonía Asociada al Ventilador/prevención & control , Anciano , Femenino , Francia , Humanos , Unidades de Cuidados Intensivos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana EdadRESUMEN
OBJECTIVE: To compare the 28-day mortality and hospital length of stay of patients with community-acquired pneumonia who were transferred to an intensive care unit on the same day of emergency department presentation (direct-transfer patients) with those subsequently transferred within 3 days of presentation (delayed-transfer patients). DESIGN: Secondary analysis of the original data from two North American and two European prospective, multicenter, cohort studies of adult patients with community-acquired pneumonia. PATIENTS: In all, 453 non-institutionalized patients transferred within 3 days of emergency department presentation to an intensive care unit were included in the analysis. Supplementary analysis was restricted to patients without an obvious indication for immediate transfer to an intensive care unit. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The sample consisted of 138 delayed-transfer and 315 direct-transfer patients, among whom 150 (33.1%) were considered to have an obvious indication for immediate intensive care unit admission. After adjusting for the quintile of propensity score, delayed intensive care unit transfer was associated with an increased odds ratio for 28-day mortality (2.07; 95% confidence interval, 1.12-3.85) and a decreased odds ratio for discharge from hospital for survivors (0.53; 95% confidence interval, 0.39-0.71). In a propensity-matched analysis, delayed-transfer patients had a higher 28-day mortality rate (23.4% vs. 11.7%; p = 0.02) and a longer median hospital length of stay (13 days vs. 7 days; p < .001) than direct-transfer patients. Similar results were found after excluding the 150 patients with an obvious indication for immediate intensive care unit admission. CONCLUSIONS: Our findings suggest that some patients without major criteria for severe community-acquired pneumonia, according to the recent Infectious Diseases Society of America/American Thoracic Society consensus guideline, may benefit from direct transfer to the intensive care unit. Further studies are needed to prospectively identify patients who may benefit from direct intensive care unit admission despite a lack of major severity criteria for community-acquired pneumonia based on the current guidelines.
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Servicio de Urgencia en Hospital , Unidades de Cuidados Intensivos , Tiempo de Internación/estadística & datos numéricos , Admisión del Paciente , Transferencia de Pacientes , Neumonía/mortalidad , Anciano , Infecciones Comunitarias Adquiridas/mortalidad , Europa (Continente) , Femenino , Humanos , Modelos Logísticos , Masculino , América del Norte , Estudios Prospectivos , Factores de TiempoRESUMEN
INTRODUCTION: To identify risk factors for early (< three days) intensive care unit (ICU) admission of patients hospitalised with community-acquired pneumonia (CAP) and not requiring immediate ICU admission, and to stratify the risk of ICU admission on days 1 to 3. METHODS: Using the original data from four North American and European prospective multicentre cohort studies of patients with CAP, we derived and validated a prediction rule for ICU admission on days 1 to 3 of emergency department (ED) presentation, for patients presenting with no obvious reason for immediate ICU admission (not requiring immediate respiratory or circulatory support). RESULTS: A total of 6560 patients were included (4593 and 1967 in the derivation and validation cohort, respectively), 303 (4.6%) of whom were admitted to an ICU on days 1 to 3. The Risk of Early Admission to ICU index (REA-ICU index) comprised 11 criteria independently associated with ICU admission: male gender, age younger than 80 years, comorbid conditions, respiratory rate of 30 breaths/minute or higher, heart rate of 125 beats/minute or higher, multilobar infiltrate or pleural effusion, white blood cell count less than 3 or 20 G/L or above, hypoxaemia (oxygen saturation < 90% or arterial partial pressure of oxygen (PaO2) < 60 mmHg), blood urea nitrogen of 11 mmol/L or higher, pH less than 7.35 and sodium less than 130 mEq/L. The REA-ICU index stratified patients into four risk classes with a risk of ICU admission on days 1 to 3 ranging from 0.7 to 31%. The area under the curve was 0.81 (95% confidence interval (CI) = 0.78 to 0.83) in the overall population. CONCLUSIONS: The REA-ICU index accurately stratifies the risk of ICU admission on days 1 to 3 for patients presenting to the ED with CAP and no obvious indication for immediate ICU admission and therefore may assist orientation decisions.
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Infecciones Comunitarias Adquiridas/fisiopatología , Unidades de Cuidados Intensivos , Internacionalidad , Admisión del Paciente , Neumonía/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Servicio de Urgencia en Hospital , Europa (Continente) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , América del Norte , Valor Predictivo de las Pruebas , Prohibitinas , Estudios Prospectivos , Medición de Riesgo/normasRESUMEN
BACKGROUND: Although the Pneumonia Severity Index (PSI) has been extensively validated, little is known of the impact of its routine use as an aid to site-of-treatment decisions for patients with pneumonia who present to emergency departments (EDs). METHODS: A prospective, observational, controlled cohort study of patients with pneumonia was conducted in 8 EDs that used the PSI (PSI-user EDs) and 8 EDs that did not use the PSI (PSI-nonuser EDs) in France. The outcomes examined included the proportion of "low-risk" patients (PSI risk classes I-III) treated as outpatients, all-cause 28-day mortality, admission of inpatients to the intensive care unit, and subsequent hospitalization of outpatients. RESULTS: Of the 925 patients enrolled in the study, 472 (51.0%) were treated at PSI-user EDs, and 453 (49.0%) were treated at PSI-nonuser EDs; 449 (48.5%) of all patients were considered to be at low risk. In PSI-user EDs, 92 (42.8%) of 215 patients at low risk were treated as outpatients, compared with 56 (23.9%) of 234 patients at low risk in PSI-nonuser EDs. The adjusted odds ratios for outpatient treatment were higher for patients in PSI risk classes I and II who were treated in PSI-user EDs, compared with PSI-nonuser EDs (adjusted odds ratio, 7.0 [95% confidence interval, 2.0-25.0] and 4.6 [95% confidence interval, 1.3-16.2], respectively), whereas the adjusted odds ratio did not differ by PSI-user status among patients in risk class III or among patients at high risk. After adjusting for pneumonia severity, mortality was lower in patients who were treated in PSI-user EDs; other safety outcomes did not differ between patients treated in PSI-user and PSI-nonuser EDs. CONCLUSIONS: The routine use of the PSI was associated with a larger proportion of patients in PSI risk classes I and II who had pneumonia and who were treated in the outpatient environment without compromising their safety.
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Bacteriemia/tratamiento farmacológico , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Toma de Decisiones , Servicio de Urgencia en Hospital , Neumonía Bacteriana/tratamiento farmacológico , Índice de Severidad de la Enfermedad , Anciano , Anciano de 80 o más Años , Bacteriemia/microbiología , Bacteriemia/mortalidad , Bacteriemia/fisiopatología , Estudios de Cohortes , Infecciones Comunitarias Adquiridas/microbiología , Infecciones Comunitarias Adquiridas/mortalidad , Infecciones Comunitarias Adquiridas/fisiopatología , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neumonía Bacteriana/microbiología , Neumonía Bacteriana/mortalidad , Neumonía Bacteriana/fisiopatología , Estudios Prospectivos , Medición de RiesgoRESUMEN
RATIONALE: Intensive care unit (ICU) admission of a relative is a stressful event that may cause symptoms of post-traumatic stress disorder (PTSD). OBJECTIVES: Factors associated with these symptoms need to be identified. METHODS: For patients admitted to 21 ICUs between March and November 2003, we studied the family member with the main potential decision-making role. MEASUREMENTS: Ninety days after ICU discharge or death, family members completed the Impact of Event Scale (which evaluates the severity of post-traumatic stress reactions), Hospital Anxiety and Depression Scale, and 36-item Short-Form General Health Survey during a telephone interview. Linear regression was used to identify factors associated with the risk of post-traumatic stress symptoms. MAIN RESULTS: Interviews were obtained for family members of 284 (62%) of the 459 eligible patients. Post-traumatic stress symptoms consistent with a moderate to major risk of PTSD were found in 94 (33.1%) family members. Higher rates were noted among family members who felt information was incomplete in the ICU (48.4%), who shared in decision making (47.8%), whose relative died in the ICU (50%), whose relative died after end-of-life decisions (60%), and who shared in end-of-life decisions (81.8%). Severe post-traumatic stress reaction was associated with increased rates of anxiety and depression and decreased quality of life. CONCLUSION: Post-traumatic stress reaction consistent with a high risk of PTSD is common in family members of ICU patients and is the rule among those who share in end-of-life decisions. Research is needed to investigate PTSD rates and to devise preventive and early-detection strategies.
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Enfermedad Crítica , Salud de la Familia , Trastornos por Estrés Postraumático/epidemiología , Adulto , Anciano , Ansiedad/epidemiología , Comunicación , Toma de Decisiones , Depresión/epidemiología , Análisis Factorial , Femenino , Indicadores de Salud , Humanos , Unidades de Cuidados Intensivos , Modelos Logísticos , Masculino , Persona de Mediana Edad , PaternalismoRESUMEN
OBJECTIVE: To evaluate the opinions of intensive care unit staff and family members about family participation in decisions about patients in intensive care units in France, a country where the approach of physicians to patients and families has been described as paternalistic. DESIGN: Prospective multiple-center survey of intensive care unit staff and family members. SETTING: Seventy-eight intensive care units in university-affiliated hospitals in France. PATIENTS: We studied 357 consecutive patients hospitalized in the 78 intensive care units and included in the study starting on May 1, 2001, with five patients included per intensive care unit. INTERVENTIONS: We recorded opinions and experience about family participation in medical decision making. Comprehension, satisfaction, and Hospital Anxiety and Depression Scale scores were determined in family members. MEASUREMENTS AND MAIN RESULTS: Poor comprehension was noted in 35% of family members. Satisfaction was good but anxiety was noted in 73% and depression in 35% of family members. Among intensive care unit staff members, 91% of physicians and 83% of nonphysicians believed that participation in decision making should be offered to families; however, only 39% had actually involved family members in decisions. A desire to share in decision making was expressed by only 47% of family members. Only 15% of family members actually shared in decision making. Effectiveness of information influenced this desire. CONCLUSION: Intensive care unit staff should seek to determine how much autonomy families want. Staff members must strive to identify practical and psychological obstacles that may limit their ability to promote autonomy. Finally, they must develop interventions and attitudes capable of empowering families.
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Actitud Frente a la Salud , Toma de Decisiones , Familia/psicología , Unidades de Cuidados Intensivos , Adulto , Anciano , Ansiedad , Actitud del Personal de Salud , Comportamiento del Consumidor , Depresión , Femenino , Francia , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios ProspectivosRESUMEN
OBJECTIVE: To evaluate the extent to which respiratory changes in inferior vena cava (IVC) diameter can be used to predict fluid responsiveness. DESIGN: Prospective clinical study. SETTING: Hospital intensive care unit. PATIENTS: Twenty-three patients with acute circulatory failure related to sepsis and mechanically ventilated because of an acute lung injury. MEASUREMENTS: Inferior vena cava diameter (D) at end-expiration (Dmin) and at end-inspiration (Dmax) was measured by echocardiography using a subcostal approach. The distensibility index of the IVC (dIVC) was calculated as the ratio of Dmax - Dmin / Dmin, and expressed as a percentage. The Doppler technique was applied in the pulmonary artery trunk to determine cardiac index (CI). Measurements were performed at baseline and after a 7 ml/kg volume expansion using a plasma expander. Patients were separated into responders (increase in CI > or =15%) and non-responders (increase in CI <15%). RESULTS: Using a threshold dIVC of 18%, responders and non-responders were discriminated with 90% sensitivity and 90% specificity. A strong relation (r = 0.9) was observed between dIVC at baseline and the CI increase following blood volume expansion. Baseline central venous pressure did not accurately predict fluid responsiveness. CONCLUSION: Our study suggests that respiratory change in IVC diameter is an accurate predictor of fluid responsiveness in septic patients.
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Insuficiencia Respiratoria/fisiopatología , Sepsis/fisiopatología , Vena Cava Inferior/patología , Adulto , Anciano , Presión Sanguínea , Presión Venosa Central , Ecocardiografía Doppler , Pruebas de Función Cardíaca , Frecuencia Cardíaca , Humanos , Unidades de Cuidados Intensivos , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Respiración Artificial , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/terapia , Sepsis/complicaciones , Sepsis/terapia , Vena Cava Inferior/fisiopatologíaRESUMEN
We describe the first fatal evolution of cellulitis due to Neisseria meningitidis serogroup Y involving an 85-year-old woman. She presented with an extensive cellulitis of the left side of the face, neck, and thorax and septic shock. In spite of active antibiotic therapy, evolution was rapidly fatal.
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Celulitis (Flemón)/microbiología , Meningitis Meningocócica/diagnóstico , Neisseria meningitidis Serogrupo Y/aislamiento & purificación , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Celulitis (Flemón)/diagnóstico por imagen , Resultado Fatal , Femenino , Francia , Humanos , Lactamas , Meningitis Meningocócica/diagnóstico por imagen , Pruebas de Sensibilidad Microbiana , Neisseria meningitidis Serogrupo Y/efectos de los fármacos , Choque Séptico/etiología , Tomografía Computarizada por Rayos XRESUMEN
Results of routine microbiologic cultures of specimens obtained before the onset of ventilator-associated pneumonia (VAP) in intensive care unit (ICU) patients might help to identify the causative microorganisms and thus to select effective initial antimicrobial therapy. To test this hypothesis, we prospectively studied 125 consecutive VAP episodes for which the causative microorganisms were determined using bronchoscopic techniques. Upon entry into the study, each patient's hospital chart was reviewed and culture results of all previously obtained microbiologic specimens were recorded (mean number +/- SD per patient, 45 +/- 38). A total of 220 microorganisms were cultured at significant concentrations (> or = 10(3)/10(4) colony-forming units [cfu]/ml) from bronchoscopic specimens and considered responsible for pneumonia. Of these 220 organisms, only 73 (33%) were recovered before VAP onset, sometimes from multiple sites in the same patient but mainly from prior respiratory secretion cultures (n = 53). Also previously isolated were 342 organisms that were not responsible for VAP, making prospective identifications of the true pathogens difficult. Among the 102 episodes for which prior respiratory secretion culture results had been obtained (mean time before VAP onset, 8 +/- 9 d), all the organisms ultimately responsible for pneumonia were previously recovered from only 36 (35%) of these specimens. Based on these data, the contribution of routine microbiologic specimens in guiding initial antimicrobial therapy decisions for patients with suspected VAP appears limited.