High or conventional positive end-expiratory pressure in adult respiratory distress syndrome.

Patients with acute respiratory distress syndrome may require high positive end-expiratory pressure (PEEP) levels, though the optimum level remains to be established. Several clinical trials have compared high PEEP levels versus conventional PEEP. Overall, although high PEEP levels improve oxygenation and are safe, they do not result in a significant reduction of the mortality rates. Nevertheless, some metaanalyses have revealed 2 situations in which high PEEP may decrease mortality: When used in severe distress and when PEEP is set following the characteristics of lung mechanics. Five studies have explored this latter scenario. Unfortunately, all of them have small sample sizes and have used different means to determine optimum PEEP. It is therefore necessary to conduct studies of sufficient sample size to compare the treatment of patients with severe acute respiratory distress syndrome, using a protective ventilation strategy with high PEEP guided by the characteristics of lung mechanics and ventilation with the protocol proposed by the ARDS Network.

Prognosis of elderly patients subjected to mechanical ventilation in the ICU.

OBJECTIVE: To analyze the prognosis of mechanically ventilated elderly patients in the Intensive Care Unit (ICU). DESIGN AND SCOPE: Sub-analysis of a prospective multicenter observational cohort study conducted over a period of two years in 13 medical-surgical ICUs in Spain. PATIENTS: Adult patients who required mechanical ventilation (MV) for longer than 24 hours. INTERVENTIONS: None. STUDY VARIABLES: Demographic data, APACHE II, SOFA, reason for MV, comorbidity, functional condition, reintubation, duration of MV, tracheotomy, ICU mortality, in-hospital mortality. RESULTS: A total of 1661 patients were recruited. Males accounted for 67.9% (n=1127), with a mean age of 62.1 ± 16.2 years. APACHE II: 20.3 ± 7.5. Total SOFA: 8.4 ± 3.5. Four hundred and twenty-three patients (25.4%) were ≥ 75 years of age. Comorbidity and functional condition rates were poorer in these patients (p<0.001 for both variables). Mortality in the ICU was higher in the elderly patients (33.6%) than in the younger subjects (25.9%) (p=0.002). Also, in-hospital mortality was higher in those ≥ 75 years of age. No differences in duration of MV, prevalence of tracheostomy or reintubation incidence were found. Regarding the indication for MV, only the patient ≥ 75 years of age with pneumonia, sepsis or trauma had a higher in-ICU mortality than the younger patients (46.3% vs 33.1%, p=0.006; 55% vs 25.8%, p=0.002; 63.6% vs 4.5%, p<0,001, respectively). No differences were found referred to other reasons for MV. CONCLUSION: Older patients (≥ 75 years) have significantly higher in-ICU and in-hospital mortality than younger patients without differences in the duration of mechanical ventilation. Differences in mortality were at the expense of pneumonia, sepsis and trauma.

[Prolonged mechanical ventilation probability model]. / Modelo de probabilidad de ventilación mecánica prolongada.

OBJECTIVE: To design a probability model for prolonged mechanical ventilation (PMV) using variables obtained during the first 24 hours of the start of MV. DESIGN: An observational, prospective, multicenter cohort study. SCOPE: Thirteen Spanish medical-surgical intensive care units. PATIENTS: Adult patients requiring mechanical ventilation for more than 24 hours. INTERVENTIONS: None. STUDY VARIABLES: APACHE II, SOFA, demographic data, clinical data, reason for mechanical ventilation, comorbidity, and functional condition. A multivariate risk model was constructed. The model contemplated a dependent variable with three possible conditions: 1. Early mortality; 2. Early extubation; and 3. PMV. RESULTS: Of the 1661 included patients, 67.9% (n=1127) were men. Age: 62.1±16.2 years. APACHE II: 20.3±7.5. Total SOFA: 8.4±3.5. The APACHE II and SOFA scores were higher in patients ventilated for 7 or more days (p=0.04 and p=0.0001, respectively). Noninvasive ventilation failure was related to PMV (p=0.005). A multivariate model for the three above exposed outcomes was generated. The overall accuracy of the model in the training and validation sample was 0.763 (95%IC: 0.729-0.804) and 0.751 (95%IC: 0.672-0.816), respectively. The likelihood ratios (LRs) for early extubation, involving a cutoff point of 0.65, in the training sample were LR (+): 2.37 (95%CI: 1.77-3.19) and LR (-): 0.47 (95%CI: 0.41-0.55). The LRs for the early mortality model, for a cutoff point of 0.73, in the training sample, were LR (+): 2.64 (95%CI: 2.01-3.4) and LR (-): 0.39 (95%CI: 0.30-0.51). CONCLUSIONS: The proposed model could be a helpful tool in decision making. However, because of its moderate accuracy, it should be considered as a first approach, and the results should be corroborated by further studies involving larger samples and the use of standardized criteria.

Presión positiva teleespiratoria alta o convencional en el síndrome de distrés respiratorio agudo / High or conventional positive end-expiratory pressure in acute respiratory distress

En el síndrome de distrés respiratorio agudo se puede necesitar una presión positiva teleespiratoria (PEEP) elevada, sin embargo, no se ha llegado a determinar cuánto. Varios ensayos clínicos han comparado esos niveles con los convencionales en este síndrome. Globalmente, aunque la PEEP elevada mejora la oxigenación y es segura, no mejora la mortalidad. No obstante, los metaanálisis han puesto de manifiesto 2 situaciones en las que una PEEP elevada puede disminuir la mortalidad: en el síndrome de distrés respiratorio agudo grave y cuando se titula mediante las características de la mecánica pulmonar. Cinco estudios han explorado esto último, todos de pequeño tamaño muestral, usando diferentes maneras de determinar la PEEP óptima. Resulta necesario, por tanto, realizar un estudio con el suficiente tamaño muestral que compare el tratamiento de pacientes con síndrome de distrés respiratorio agudo grave mediante una estrategia de ventilación protectora, con PEEP elevada, guiada por las características de la mecánica pulmonar y la ventilación según el protocolo de la ARDS Network

Patients with acute respiratory distress syndrome may require high positive endexpiratory pressure (PEEP) levels, though the optimum level remains to be established. Several clinical trials have compared high PEEP levels versus conventional PEEP. Overall, although high PEEP levels improve oxygenation and are safe, they do not result in a significant reduction of the mortality rates. Nevertheless, some metaanalyses have revealed 2 situations in which high PEEP may decrease mortality: When used in severe distress and when PEEP is set following thec haracteristics of lung mechanics. Five studies have explored this latter scenario. Unfortunately, all of them have small sample sizes and have used different means to determine optimum PEEP. It is therefore necessary to conduct studies of sufficient sample size to compare the treatment of patients with severe acute respiratory distress syndrome, using a protective ventilation strategy with high PEEP guided by the characteristics of lung mechanics and ventilation with the protocol proposed by the ARDS Network

[High PEEP vs. conventional PEEP in the acute respiratory distress syndrome: a systematic review and meta-analysis]. / PEEP alta frente a PEEP convencional en el síndrome de distrés respiratorio agudo. Revisión sistemática y metaanálisis.

OBJECTIVE: To perform a systematic review and meta-analysis of the literature to evaluate the effects of high PEEP versus conventional PEEP on mortality and on the risk of barotrauma in patients with the acute respiratory distress syndrome (ARDS). SOURCE OF DATA: Computer search of Medline, Embase, CINAHL, CANCERLIT, Pascal-Biomed, ACP Journal Club, Cochrane library (CDSR, DARE, CCTR), ISI Proceedings, Current Contents, and Web of Science, as well as manual search of selected references. SELECTION OF STUDIES: Controlled random clinical trials published after NAECC (1994) that evaluated the effect of two levels of PEEP and that reported the mortality and incidence of barotrauma in the series. DATA EXTRACTION: By two investigators working independently, with discrepancies resolved by group consensus. Contingency tables were elaborated and the RRs with corresponding confidence intervals were obtained for each study. RESULTS: Four articles were selected for the meta-analysis of mortality and three for the meta-analysis of barotrauma. No effects of PEEP level on mortality were found (RR 0.73, 95% CI: 0.49 to 1.10) or on the incidence of barotrauma (RR 0.50, 95% CI: 0.14 to 1.73). However, an analysis of the studies in which PEEP was individualized in function of Pflex showed a significant decrease in mortality (RR 0.59, 95% CI: 0.43 to 0.82) (p=0.001) CONCLUSIONS: The use of high or conventional PEEP in function of oxygenation does not affect mortality or the incidence of barotrauma in patients with ARDS. However, there might be a decrease in mortality associated to high PEEP individualized in function of the pulmonary mechanics of each patient.

Modelo de probabilidad de ventilación mecánica prolongada / Prolonged mechanical ventilation probability model

Objetivo: Diseñar un modelo de probabilidad de ventilación mecánica prolongada (VMP) con variables clínicas obtenidas durante las primeras 24 horas de su instauración. Diseño: Estudio de cohorte, observacional, prospectivo, multicéntrico. Ámbito: Trece UCI españolas polivalentes. Pacientes: Adultos ventilados durante más de 24 horas. Intervenciones: Ninguna. Variables de interés: APACHE II, SOFA, variables clínicas y demográficas, motivo de VM, comorbilidad y estado funcional. Se construyó un modelo de riesgo multivariante en el que la variable dependiente tenía tres posibles estados: 1.- Muerte precoz. 2.- Retirada precoz de la VM. 3.- VMP. Resultados: Se incluyeron 1.661 pacientes. El 67,9% (n=1.127) fueron hombres. Edad: 62,1±16,2 años. APACHE II: 20,3±7,5. SOFA: 8,4±3,5. Las puntuaciones APACHE II y SOFA fueron mayores en pacientes ventilados > 7 días (p=0,04 y p=0,0001 respectivamente). El fracaso de la ventilación no invasiva (VNI) se asoció a VMP (p=0,005). Se generó un modelo de riesgo multivariante con las siguientes variables: APACHE II, SOFA, fracaso de VNI, ubicación hospitalaria antes del ingreso en UCI y motivo de ventilación mecánica. La exactitud del modelo global (..) (AU)

Objective: To design a probability model for prolonged mechanical ventilation (PMV) using variables obtained during the first 24hours of the start of MV. Design: An observational, prospective, multicenter cohort study. Scope: Thirteen Spanish medical-surgical intensive care units. Patients: Adult patients requiring mechanical ventilation for more than 24hours. Interventions: None. Study variables: APACHE II, SOFA, demographic data, clinical data, reason for mechanical ventilation, comorbidity, and functional condition. A multivariate risk model was constructed. The model contemplated a dependent variable with three possible conditions: 1. Early mortality; 2. Early extubation; and 3. PMV. Results: Of the 1661 included patients, 67.9% (n=1127) were men. Age: 62.1±16.2 years. APACHE II: 20.3±7.5. Total SOFA: 8.4±3.5. The APACHE II and SOFA scores were higher in patients ventilated for 7 or more days (p=0.04 and p=0.0001, respectively). Noninvasive ventilation failure was related to PMV (p=0.005). A multivariate model for the three above exposed outcomes was generated. The overall accuracy of the model in the training and validation sample was 0.763 (95%IC: 0.729-0.804) and 0.751 (95%IC: 0.672-0.816), respectively. The likelihood ratios (LRs) for early extubation, involving a cutoff point of 0.65, in the training sample were LR (+): 2.37 (95%CI: 1.77-3.19) and LR (-): 0.47 (95%CI: 0.41-0.55). The LRs for the early mortality model, for a cutoff point of 0.73, in the training sample, were LR (+): 2.64 (95%CI: 2.01-3.4) and LR (-): 0.39 (95%CI: 0.30-0.51). Conclusions: The proposed model could be a helpful tool in decision making. However, because of its moderate accuracy, it should be considered as a first approach, and the results should be corroborated by further studies involving larger samples and the use of standardized criteria (AU)

[Use of internet and electronic resources among Spanish intensivist physicians. First national survey]. / Uso de Internet y recursos electrónicos entre médicos intensivistas españoles. Primera encuesta nacional.

OBJECTIVE: Estimate knowledge and use habits of different electronic resources in a sample of Spanish intensivists: Internet, E-mail, distribution lists, and use of portable electronic devices. DESIGN: Self-applied questionnaire. METHODS: A 50-question questionnaire was distributed among Spanish intensivists through the hospital marketing delegates of a pharmaceutical company and of electronic forums. RESULTS: A total of 682 questionnaires were analyzed (participation: 74%). Ninety six percent of those surveyed used Internet individually: 67% admitted training gap. Internet was the second source of clinical consultations most used (61%), slightly behind consultation to colleagues (65%). The pages consulted most were bibliographic databases (65%) and electronic professional journals (63%), with limited use of Evidence Based Medicine pages (19%). Ninety percent of those surveyed used e-mail regularly in the practice of their profession, although 25% admitted that were not aware of its possibilities. The use of E-mail decreased significantly with increase in age. A total of 62% of the intensivists used distribution lists. Of the rest, 42% were not aware of its existence and 32% admitted they had insufficient training to handle them. Twenty percent of those surveyed had portable electronic devices and 64% considered it useful, basically due to its rapid consultation at bedside. Female gender was a negative predictive factor of its use (OR 0.35; 95% CI 0.2-0.63; p=0.0002). CONCLUSIONS: A large majority of the Spanish intensivists use Internet and E-mail. E-mail lists and use of portable devices are still underused resources. There are important gaps in training and infrequent use of essential pages. There are specific groups that require directed educational policies.

Pronóstico de los ancianos ventilados mecánicamente en la UCI / Prognosis of elderly patients subjected to mechanical ventilation in the ICU

Objetivo Analizar el pronóstico de los pacientes ancianos ventilados mecánicamente en la Unidad de Cuidados Intensivos (UCI).Diseño y ámbito Análisis secundario de un estudio observacional prospectivo y multicéntrico llevado a cabo durante un periodo de 2 años en 13 UCI españolas. Pacientes Pacientes adultos que precisaron ventilación mecánica (VM) invasiva durante más de 24 horas. Intervencione Ninguna. Variables de interés Datos demográficos, APACHE II, SOFA, motivo de VM, comorbilidad, situación funcional, reintubación, duración de la VM, traqueotomía, mortalidad en la UCI, mortalidad hospitalaria. Resultados Se incluyeron 1.661 pacientes. De ellos 1.127 (67,9%) eran hombres. Edad: 62,1±16,2 años. APACHE II: 20,3±7,5. SOFA total: 8,4±3,5. Cuatrocientos veintitrés pacientes (25,4%) tenían 75 años o más. Los índices de comorbilidad y capacidad funcional fueron peor en este grupo de pacientes (p<0,001 para ambas variables). La mortalidad en la UCI fue superior en este grupo (33,6%) que en los más jóvenes (25,9%) (p=0,002), al igual que la mortalidad hospitalaria (41,8 vs 31,8%; p<0,0001). No hubo diferencias en cuanto a tiempo de VM, incidencia de traqueotomías o índice de reintubaciones. Por causas de VM solo los pacientes ≥ 75 años ventilados por neumonía, sepsis o trauma presentaron una mortalidad en UCI más alta que los menores de esa edad (46,3 vs 33,1% p=0,006; 55 vs 25,8% p=0,002; 63,6 vs 4,5% p<0,001 respectivamente).Conclusiones Los ancianos (≥ 75 años) tienen una mayor mortalidad en UCI y hospitalaria que los más jóvenes sin diferencias en la duración de la VM. Las diferencias son a expensas de patologías como neumonía, sepsis y trauma (AU)

Objective To analyze the prognosis of mechanically ventilated elderly patients in the Intensive Care Unit (ICU).Design and scope Sub-analysis of a prospective multicenter observational cohort study conducted over a period of two years in 13 medical-surgical ICUs in Spain. Patients Adult patients who required mechanical ventilation (MV) for longer than 24hours.InterventionsNone.Study variables Demographic data, APACHE II, SOFA, reason for MV, comorbidity, functional condition, reintubation, duration of MV, tracheotomy, ICU mortality, in-hospital mortality. Results A total of 1661 patients were recruited. Males accounted for 67.9% (n=1127), with a mean age of 62.1±16.2 years. APACHE II: 20.3±7.5. Total SOFA: 8.4±3.5. Four hundred and twenty-three patients (25.4%) were ≥ 75 years of age. Comorbidity and functional condition rates were poorer in these patients (p<0.001 for both variables). Mortality in the ICU was higher in the elderly patients (33.6%) than in the younger subjects (25.9%) (p=0.002). Also, in-hospital mortality was higher in those ≥ 75 years of age. No differences in duration of MV, prevalence of tracheostomy or reintubation incidence were found. Regarding the indication for MV, only the patient ≥ 75 years of age with pneumonia, sepsis or trauma had a higher in-ICU mortality than the younger patients (46.3% vs 33.1%, p=0.006; 55% vs 25.8%, p=0.002; 63.6% vs 4.5%, p<0,001, respectively). No differences were found referred to other reasons for MV. Conclusion Older patients (≥ 75 years) have significantly higher in-ICU and in-hospital mortality than younger patients without differences in the duration of mechanical ventilation. Differences in mortality were at the expense of pneumonia, sepsis and trauma (AU)

PEEP alta frente a PEEP convencional en el síndrome de distrés respiratorio agudo Revisión sistemática y metaanálisis / High PEEP vs. conventional PEEP in the acute respiratory distress syndrome: a systematic review and meta-analysis

Objetivo. Evaluar, mediante revisión sistemática y metaanálisis, el efecto de presión positiva al final de la espiración (PEEP) alta frente PEEP convencional sobre la mortalidad y riesgo de barotrauma de los pacientes con síndrome de distrés respiratorio agudo (SDRA). Fuente de datos. Búsqueda electrónica en Medline, Embase, CINAHL, CANCERLIT, Pascal-Biomed, ACP Journal Club, biblioteca Cochrane (CDSR, DARE, CCTR), ISI Proceedings, Current Contents y Web of Science y búsqueda manual sobre las referencias seleccionadas. Selección de estudios. Ensayos clínicos controlados aleatorizados publicados tras la NAECC (1994) que evaluaran el efecto de dos niveles de PEEP y que informaran sobre la mortalidad e incidencia de barotrauma. Extracción de datos. Independiente por dos investigadores y las discrepancias se resuelven por consenso en el grupo. Se realizaron las tablas de contingencia y se obtuvieron los riesgos relativos (RR) con los intervalos de confianza (IC) de cada estudio. Resultados. Se seleccionaron 4 artículos para el metaanálisis de mortalidad y 3 para el de barotrauma. No se encontró efecto de ninguno de los niveles de PEEP sobre la mortalidad (RR 0,73, IC 95%: 0,49 a 1,10) ni sobre la incidencia de barotrauma (RR 0,59, IC 95%: 0,14 a 1,73). Sin embargo, analizando los estudios en los que la PEEP se individualizó en función del punto de inflexión (Pflex), se objetiva una reducción significativa de la mortalidad (RR 0,59, IC 95%: 0,43 a 0,82) (p = 0,001). Conclusiones. El empleo de PEEP alta o convencional en función de la oxigenación no afecta a la mortalidad o a la incidencia de barotrauma en pacientes con SDRA. Sin embargo, es posible que exista una reducción de la mortalidad asociada al empleo de PEEP alta individualizada en función de la mecánica pulmonar de cada paciente

Objective. To perform a systematic review and meta-analysis of the literature to evaluate the effects of high PEEP versus conventional PEEP on mortality and on the risk of barotrauma in patients with the acute respiratory distress syndrome (ARDS). Source of data. Computer search of Medline, Embase, CINAHL, CANCERLIT, Pascal-Biomed, ACP Journal Club, Cochrane library (CDSR, DARE, CCTR), ISI Proceedings, Current Contents, and Web of Science, as well as manual search of selected references. Selection of studies. Controlled random clinical trials published after NAECC (1994) that evaluated the effect of two levels of PEEP and that reported the mortality and incidence of barotrauma in the series. Data extraction. By two investigators working independently, with discrepancies resolved by group consensus. Contingency tables were elaborated and the RRs with corresponding confidence intervals were obtained for each study. Results. Four articles were selected for the meta-analysis of mortality and three for the meta-analysis of barotrauma. No effects of PEEP level on mortality were found (RR 0.73, 95% CI: 0.49 to 1.10) or on the incidence of barotrauma (RR 0.50, 95% CI: 0.14 to 1.73). However, an analysis of the studies in which PEEP was individualized in function of Pflex showed a significant decrease in mortality (RR 0.59, 95% CI: 0.43 to 0.82) (p = 0.001) Conclusions. The use of high or conventional PEEP in function of oxygenation does not affect mortality or the incidence of barotrauma in patients with ARDS. However, there might be a decrease in mortality associated to high PEEP individualized in function of the pulmonary mechanics of each patient