Neurally adjusted ventilatory assist vs pressure support ventilation in infants recovering from severe acute respiratory distress syndrome: nested study.

OBJECTIVE: Neurally adjusted ventilatory assist (NAVA) is a new ventilator modality with an innovative synchronization technique. Our aim is to verify if NAVA is feasible and safe in terms of physiological and clinical variables in infants recovering from severe acute respiratory distress syndrome (ARDS). DESIGN: This is a pilot nested study to help future trial design. SETTING: The study was performed in third-level academic pediatric intensive care units. PATIENTS: Infants affected by severe ARDS requiring high-frequency ventilation and weaned with NAVA during 2010 were included. Controls (2:1 ratio) were ARDS infants weaned with pressure support ventilation (PSV) during 2008-2009 matched for age, gas exchange impairment, and weight. MAIN OUTCOME MEASURES: The main outcome measures were the physiological and ventilator parameters and the duration of ventilator support in PSV or NAVA. RESULTS: Ten infants treated with NAVA and 20 with PSV were studied. Heart rate (P < .001) and mean arterial pressure (P < .001) increased less during NAVA than during PSV. Similarly, Pao2/Fio2 ratio decreased less in NAVA than in PSV (P < .001). Neurally adjusted ventilatory assist also resulted in lower Paco2 (P < .001) and peak pressure (P = .001), as well as higher minute ventilation (P = .013). COMFORT score (P = .004) and duration of support were lower in NAVA than in PSV (P = .011). CONCLUSIONS: Neurally adjusted ventilatory assist is safe and suitable in infants recovering from severe ARDS. It could provide better results than PSV and is worth to be investigated in a multicenter randomized trial.

Ex vivo effect of varespladib on secretory phospholipase A2 alveolar activity in infants with ARDS.

BACKGROUND: Secretory phospholipase A2 (sPLA2) plays a pivotal role in acute respiratory distress syndrome (ARDS). This enzyme seems an interesting target to reduce surfactant catabolism and lung tissue inflammation. Varespladib is a specifically designed indolic sPLA2 inhibitor, which has shown promising results in animals and adults. No specific data in pediatric ARDS patients are yet available. METHODS: We studied varespladib in broncho-alveolar lavage (BAL) fluids obtained ex vivo from pediatric ARDS patients. Clinical data and worst gas exchange values during the ARDS course were recorded. Samples were treated with saline or 10-40-100 µM varespladib and incubated at 37°C. Total sPLA2 activity was measured by non-radioactive method. BAL samples were subjected to western blotting to identify the main sPLA isotypes with different sensitivity to varespladib. Results was corrected for lavage dilution using the serum-to-BAL urea ratio and for varespladib absorbance. RESULTS: Varespladib reduces sPLA2 activity (p<0.0001) at 10,40 and 100 µM; both sPLA2 activity reduction and its ratio to total proteins significantly raise with increasing varespladib concentrations (p<0.001). IC(50) was 80 µM. Western blotting revealed the presence of sPLA2-IIA and -IB isotypes in BAL samples. Significant correlations exist between the sPLA2 activity reduction/proteins ratio and PaO(2) (rho = 0.63;p<0.001), PaO(2)/FiO(2) (rho = 0.7; p<0.001), oxygenation (rho = -0.6; p<0.001) and ventilation (rho = -0.4;p = 0.038) indexes. CONCLUSIONS: Varespladib significantly inhibits sPLA2 in BAL of infants affected by post-neonatal ARDS. Inhibition seems to be inversely related to the severity of gas exchange impairment.

The number of failing organs predicts non-invasive ventilation failure in children with ALI/ARDS.

PURPOSE: Non-invasive positive pressure ventilation (NIV) is being increasingly used in paediatric critical care, although its use in acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) is still debated. No definite data are available for the prediction of NIV outcome in such selected populations. We aimed to identify which factors might affect NIV failure in paediatric ALI/ARDS patients. METHODS: A retrospective cohort study using comprehensive predictivity analysis was performed. All children admitted to our paediatric intensive care unit over a 4-year period for ALI/ARDS were reviewed. Basic, clinical, physiological parameters and their change after 1 h of NIV were considered and subjected to univariate analysis. Candidate prognostic variables were then subjected to multicollinearity scrutiny and logistic regression. Finally, variables significant in the logistic regression were subjected to predictivity analysis. RESULTS: The number of organ failures at admission (NOF) is a strong predictor of NIV failure (odds ratio 5.26; p = 0.004). Having only one organ failure provides a probability of NIV success of 85.7% (sensitivity 87%; specificity 49%). One NIV failure will be predicted and avoided for every four cases in which the presence of other organ failures is incorporated into the clinical decision. CONCLUSIONS: NOF significantly predicts the NIV failure. Children with no organ failures other than ALI/ARDS may safely be treated with NIV.

Tension chylothorax complicating acute malignant airway obstruction.

Acute upper airway obstruction represents one of the most challenging emergencies in pediatric practice. In particular, a tension chylothorax complicating a malignant airway obstruction is a rare and life-threatening complication. We report a rapidly progressing tension chylothorax associated with a cervical mass in a 10-month-old male infant. To our knowledge, the extension of a cervical mass to the supraclavear region resulting in a compressive chylothorax represents an exceptional event in pediatrics. Early recognition and prompt treatment resulted to be essential to relieve the compression and to avoid end-stage hemodynamic and respiratory function derangement.

Neurogenic stunned myocardium presenting as left ventricular hypertrabeculation in childhood: a variant of Takotsubo cardiomyopathy?

OBJECTIVE: To report the first case of neurogenic stunned myocardium presenting with heart left ventricle noncompaction requiring intensive care in the perioperative period of tension tumor-induced hydrocephalus. METHODS AND DESIGN: Case report and literature review. Our Institutional Review Board waived the need for consent. PATIENT: A 12-yr-old female with intracranial astrocytoma and hypertensive hydrocephalus presented with severe heart dysfunction and life-threatening ventricular ectopies intraoperatively. A severe heart failure developed requiring hemodynamic and ventilatory support for 10 days. Echocardiography showed a transient noncompaction aspect of the left ventricular wall, further confirmed by a cardiac magnetic resonance image. The noncompaction aspect lasted until 15 days postadmission, as was the case for the QT interval prolongation; no life-threatening ectopies were demonstrated on the subsequent Holter electrocardiogram monitoring. CONCLUSIONS: This report describes a unique presentation of myocardial stunning in association with an intracranial illness, namely, a hypertensive hydrocephalus complicating an intracranial neoplasm.