Prognostic value of cerebral tissue oxygen saturation during neonatal extracorporeal membrane oxygenation.

OBJECTIVES: Extracorporeal membrane oxygenation support is indicated in severe and refractory respiratory or circulatory failures. Neurological complications are typically represented by acute ischemic or hemorrhagic lesions, which induce higher morbidity and mortality. The primary goal of this study was to assess the prognostic value of cerebral tissue oxygen saturation (StcO2) on mortality in neonates and young infants treated with ECMO. A secondary objective was to evaluate the association between StcO2 and the occurrence of cerebral lesions. STUDY DESIGN: This was a prospective study in infants < 3 months of age admitted to a pediatric intensive care unit and requiring ECMO support. MEASUREMENTS: The assessment of cerebral perfusion was made by continuous StcO2 monitoring using near-infrared spectroscopy (NIRS) sensors placed on the two temporo-parietal regions. Neurological lesions were identified by MRI or transfontanellar echography. RESULTS: Thirty-four infants <3 months of age were included in the study over a period of 18 months. The ECMO duration was 10±7 days. The survival rate was 50% (17/34 patients), and the proportion of brain injuries was 20% (7/34 patients). The mean StcO2 during ECMO in the non-survivors was reduced in both hemispheres (p = 0.0008 right, p = 0.03 left) compared to the survivors. StcO2 was also reduced in deceased or brain-injured patients compared to the survivors without brain injury (p = 0.002). CONCLUSION: StcO2 appears to be a strong prognostic factor of survival and of the presence of cerebral lesions in young infants during ECMO.

Transpulmonary thermodilution enables to detect small short-term changes in extravascular lung water induced by a bronchoalveolar lavage.

OBJECTIVE: To take the opportunity of a bronchoalveolar lavage to challenge the transpulmonary thermodilution for detecting the time course of changes in extravascular lung water. DESIGN: Observational study. SETTING: Medical ICU. PATIENTS: Mechanically ventilated patients in whom a bronchoalveolar lavage by bronchoscopy was performed. INTERVENTION: Transpulmonary thermodilution before and after bronchoalveolar lavage. MEASUREMENTS AND MAIN RESULTS: Before and at different times after bronchoalveolar lavage, transpulmonary thermodilution was performed to record the value of indexed extravascular lung water. For each measurement, the values of three thermodilution measurements were averaged at the following steps: before bronchoalveolar lavage, after bronchoalveolar lavage, and 1 hour, 2 hours, 4 hours, and 6 hours after bronchoalveolar lavage. The amount of saline infusion left in the lungs after bronchoalveolar lavage was also recorded. Twenty-five patients with suspicion of pneumonia were included. Twenty-eight bronchoalveolar lavages were finally analyzed. On average, 200 mL (180-200 mL) of saline were injected and 130 mL (100-160 mL) were left in the lungs. Between before and immediately after bronchoalveolar lavage, indexed extravascular lung water significantly increased from 12 ± 4 to 15 ± 5 mL/kg, respectively, representing a 169 ± 166 mL increase in nonindexed extravascular lung water. After bronchoalveolar lavage, the value of indexed extravascular lung water was significantly different from the baseline value until 2 hours after bronchoalveolar lavage and became similar to the baseline value thereafter. CONCLUSIONS: Transpulmonary thermodilution enabled to detect small short-term changes of indexed extravascular lung water secondary to bronchoalveolar lavage.