Síndrome de destret respiratori agutexperiència en una UCI pediàtrica

Abstract

Background. Despite recent advances, the acute respiratory distress syndrome (ARDS) continues to have very high mortality rates. In the pediatric literature, initial alveolar-arterial oxygen tension difference [D (a-A) O2] has been described as a useful prognostic factor. A value of [D (a-A) O2] higher than 420 mmHg during more than 16 hours correlates with high mortality, and this is a parameter used to select the patients that would be candidates for extracorporeal membrane oxygenation (ECMO). Objectives. 1) To report the incidence and evolution of ARDS in patients admitted to a PICU. 2) To describe the response of the oxygenation index to the use of PEEP > 5 cm H2O. 3) To evaluate the prognostic value of the oxygenation index in the first 48 hours following the diagnosis of ARDS. Methods. 1) Retrospective study performed between January 1995 and May 2000, including all patients (age 1 month - 18 years) diagnosed with ARDS in the PICU. 2) The oxygenation indexes, including the alveolar-arterial oxygen tension difference [D (a-A) O2], and the arterio-alveolar oxygen index [I (a-A) O2], were calculated at diagnosis and after using PEEP > 5 cm H2O. 3) Evaluation of the correlation between changes in oxygenation indexes at diagnosis and at 48 hours, and outcome. Results. A total of 20 patients were included in the study. The cause of the ARDS was an infectious pulmonary process in 12 patients, sepsis in 6 patients, aspiration pneumonia in 1 case, and pulmonary contusion in 1 case. After the use of PEEP > 5 cm H2O, the PaO2/FiO2 index increased significantly (p < 0.005). Other oxygenation parameters also improved, but none reached statistical significance. No correlation was found between the oxygenation indexes and death probability. In this study, a value of [D (a-A) O2] > 420 mm Hg did not predict death due to ARDS. Conclusions. 1) The use of high PEEP significantly improves the PaO2/FiO2 index. 2) In this study, the initial [D (a-A) O2] did not have a prognostic value.