Evaluación de la ventilación mecánica no invasiva en pacientes con insuficiencia respiratoria aguda / Evaluation of non-invasive ventilation in patients with acute respiratory failure

Antecedentes: Existe evidencia que avala la utilidad de la ventilación mecánica no invasiva (VMNI) en el manejo de la insuficiencia respiratoria aguda (IRA), no obstante, la definición de variables que permitan predecir el éxito o fracaso de este recurso terapéutico es controversial. Objetivo: Evaluar el comportamiento de parámetros clínicos y de laboratorio en relación con el éxito o fracaso de la VMNI en pacientes con IRA. Metodología: Estudio prospectivo de cohorte descriptivo que incluye pacientes consecutivos que cumplieron con criterios de conexión a VMNI e ingresaron a la UPC de Clínica Alemana de Santiago entre marzo de 2005 y julio de 2007. Los pacientes se dividieron en dos grupos, aquellos que fracasan con VMNI y requirieron intubación, grupo fracaso (GF) y los que no la requirieron, grupo éxito (GE). Se registraron variables demográficas, APACHE II, diagnóstico de ingreso. La mecánica respiratoria, gasometría arterial y hemodinámica se obtuvieron en tres momentos de la evolución evolución: previo a la conexión, a las dos horas y al término del uso de VMNI (preintubación y destete de VMNI). Resultados: De los 132 pacientes incluidos se logró evitar la intubación en 99 de ellos (75 por ciento), 33 fueron intubados (25 por ciento), de los cuales 1 falleció. El pH fue menor en el GF (7,42+/-0,06 v/s 7,39+/-0,08; p =0,04). La saturación de oxígeno por pulsioximetría (SpO2) también fue menor en el GF tanto a las dos horas (96+/-2 v/s 95+/-3; p=0,01) como al final del uso de VMNI (96+/-2 v/s 95+/-3; p =0,04). La PaO2/FiO2 fue menor en el mismo grupo, en los tres momentos de medición: previo a la conexión (196+/-66 v/s 144+/-59; p =0,001), a las dos horas (223+/-92 v/s 179+/-88;p =0,022) y al término del uso de VMNI (252+/-78 v/s 208+/-104; p =0,021). Al final del uso de VMNI, tanto la frecuencia cardiaca (FC) (86+/-16 v/s 94+/-20; p =0,03) como el nivel de IPAP (12+/-2 v/s 13+/-3; p =0,02) fueron mayores en el GF. Conclusiones: El GF muestra..

Background: There is evidence supporting the benefits of non-invasive ventilation (NIV) in the treatment of acute respiratory failure (ARF), however, the role of different variables in the evaluation of this technique’s success are controversial. Objective: To evaluate the performance of the different clinical parameters and relate them with the success and failure of NIV in patients with ARF. Methodology: Prospective study of descriptive cohort that includes consecutive patients who fulfilled criteria of connection to NIV and entered to the ICU (Intensive Care Unit)of Clínica Alemana de Santiago between March of 2005 to July 2007. These patients were divided into two groups, those presenting failure with NIV and required intubation, failure group (GF) and those that did not require it, success sgroup (GE). The demographic registered variables measured were APACHE II, diagnosis of entrance were registered. The respiratory mechanics, arterial gasometry and haemodynamics were obtained at three moments of the evolution: previous to the connection, the two hours and at the end of the use of NIV (pre-intubation and weaning of NIV). Results: From the 132 patients included, intubation was avoided in 99 of them (75 percent) 33 percent were entubated from which only 1 died. The pH was lower in the FG (7.42 +/- 0.06v/s 7.39 +/- 0.08; p = 0.04). The oxygen saturation by pulsometry (SpO2), was also lower in the GF after two hours (96+/-2 v/s 95+/-3; p =0.01) and at the end of NIV use (96+/-2 v/s 95+/-3; p =0.04). The PaO2/FiO2 was lower in the same group, at the three moments of measurement: previous to the connection (196+/-66 v/s 144+/-59; p =0.001), two hours post connection (223+/-92 v/s 179+/-88; p =0.022) and at the end of the NIV use (252+/-78 v/s 208+/-104; p =0.021). At the end of the NIV use both, the cardiac frequency (FC) (86+/-16 v/s94+/-20; p =0.03) and the IPAP level (12+/-2 v/s 13+/-3; p=0.02)...

Balance hídrico y uso de drogas vasoactivas como predictores de mortalidad en pacientes con lesión pulmonar aguda y síndrome de distress respiratorio agudo: Estudio multicéntrico / Water balance and drug use vasoactive as predictors of mortality in patients with acute lung injury and respiratory distress syndrome acute: Multicentric study

Introducción. Desde la década de 1990, la mortalidad por el síndrome de distress respiratorio agudo ha disminuido. Sin embargo, no hay datos concluyentes acerca de que una nueva estrategia sea responsable de esta evolución (p. ej., el manejo de los fluidos). Aún no se ha dilucidado cuál es la cantidad óptima de fluidos para tratar a estos pacientes. Clásicamente la discusión se basa en estrategias liberales o conservadoras. Objetivo. El objetivo principal fue conocer cómo impacta el balance de fluidos asociado con el uso de noradrenalina en la evolución. Materiales y métodos. Se llevó a cabo un estudio observacional en 87 pacientes con síndrome de distress respiratorio agudo entre agosto y diciembre de 2007, en tres hospitales universitarios. Se utilizó el protocolo de tratamiento estándar de las Unidades de Cuidados Intensivos permitiendo la expansión en forma liberal cuando se sospechaba hipovolemia no resuelta. Resultados. Se detectaron tres situaciones de mayor riesgo y mala evolución: a) la asociación de noradrenalina y balance positivo de fluidos <2500 ml en las primeras 24 h (OR: 5,4; IC95%: 2,1-13,9; p = 0,0004), b) la asociación de noradrenalina y balance acumulativo >5500 ml en las primeras 72 h (OR: 2,7; IC95%: 1,1-6,5; p = 0,032) y c) pacientes con puntaje APACHE II >21, noradrenalina y balance positivo <2500 ml en las primeras 24 h (OR: 8,4; IC95%: 1,8-39; p = 0,008). Conclusión. La utilización de noradrenalina y escaso fluido en estrategias de reanimación que intentan "proteger" al pulmón con lesión parece no ser adecuada, según este estudio observacional(AU)

Introduction. Recent studies have shown an important decline in mortality due to acute respiratory distress syndrome since 1990. However, to date, there is no definitive evidence to demonstrate that any mode of specific therapeutic approach (i.e., fluid management) make a difference in survival or other outcome measures. The optimal fluid management of acute lung injury is not established. Classically there are two arguments: the wet or dry strategy. Objective. The main goal was to know the impact on outcome of fluid balance and the use of noradrenaline as a vasoactive drug. Materials and methods. In this observational study, 87 ventilated patients with acute respiratory distress syndrome were included from August to December 2007 in three University Critical Care Units. A standard protocol of resuscitation was used, fluid intake was liberal only in hypovolemic patients. Results. Three categories of risk and poor outcome were detected: a) noradrenaline plus positive fluid balance <2500 mL in first day (OR: 5.4; IC95%: 2.1-13.9; p = 0.0004), b) noradrenaline plus a cumulative positive balance >550 mL in first 72 hours (OR: 2.7; IC95%: 1.1-6.5; p = 0.032), c) APACHE II >21 and noradrenaline plus positive fluid balance <2500 mL in the first day (OR: 8.4; IC95%: 1.8-39; p = 0.008). Conclusion. The use of noradrenaline and conservative resuscitation with fluid in critically ill patients with acute respiratory distress syndrome in order to minimize the risk of excessive fluid therapy was associated with poor outcome and higher mortality(AU)

Síndrome cardiopulmonar por Hantavirus: utilidad de la monitorización con el sistema PiCCO / Hantavirus cardiopulmonary syndrome: utility of the PICCO(Pulse contour cardiac output) system for monitoring

We report a 68 years old man, farmer from the metropolitan region, admitted with a Hantavirus Cardiopulmonary Syndrome. The diagnosis was made using serologic test and was later confirmed by the Public Health Institute. He evolved to an early multiple organ failure, requiring high concentrations of oxygen and invasive ventilatory assistance, vasopressor drugs and renal replacement therapy. Swan Ganz and PiCCO were used simultaneously for hemodynamic monitoring. Treatment consisted in global support therapy, antimicrobial therapy and systemic corticosteroids. Intrathoracic blood volume was a more reliable parameter than pulmonary capillary wedge pressure for the assessment of preload. As expected in situations of increased vascular permeability, there was an increase in extravascular lung water. There was a good correlation between extravascular lung water and oxygenation parameters (PaO2/FiO2 and oxygenation index). PiCCO system may become a helpful tool in the management of patients with Hantavirus Cardiopulmonary Syndrome.

Impacto hemodinámico de la presión positiva de fin de espiración (PEEP) durante la falla respiratoria grave: visión actual / Hemodynamic impact of positive end expiratory pressure (PEEP) during severe respiratory failure: present view

Bedside evaluation of pulmonary mechanics and thoracic computed axial tomography have changed the ventilatory management of patients suffering an acute respiratory failure caused by adult respiratory distress syndrome (ARDS). Mortality has been reduced limiting tidal volumes, which avoids alveolar overdistention and by the use of positive end expiratory pressure (PEEP), that reduces the damage caused by cyclical alveolar collapse-reopening. Nowadays, it is well known that inappropriate mechanical ventilation enhances lung damage caused by the underlying disease. However, the optimal adjustment of PEEP is not yet established. Usually, it is not easy to achieve an equilibrium between an optimal lung recruitment without producing alveolar overdistention and hemodynamic adverse effects such as hypotension and reduction of cardiac output. This paper reviews the interactions between heart and lung.