Pediatric pulmonology
-
Pediatric pulmonology · Feb 2009
The impact of instrumental dead-space in volume-targeted ventilation of the extremely low birth weight (ELBW) infant.
Volume-targeted ventilation is increasingly used in neonatal ventilation to reduce the risk of volutrauma and inadvertent hyperventilation. However, normative data for appropriate tidal volume (V(T)) settings are lacking, especially in extremely low birth weight (ELBW) infants in whom the added dead space (DS) of the flow sensor may be important. ⋯ Effective alveolar ventilation occurs with V(T) at or below calculated DS. This can be explained by the fact that at the high flow rates seen in these tiny infants who have extremely short inspiratory times, fresh gas penetrates through the dead space gas, rather than pushing it ahead. Therefore there is no need to forego synchronized and volume targeted ventilation because of dead space concerns. In infants <800 g, initial V(T) of 5-6 mL/kg was associated with normocapnia when using assist/control or pressure support ventilation.
-
Pediatric pulmonology · Jan 2009
Strategic plan for pediatric respiratory diseases research: an NHLBI working group report.
The Division of Lung Diseases of the National Heart, Lung and Blood Institute (NHLBI) recently held a workshop to identify gaps in our understanding and treatment of childhood lung diseases and to define strategies to enhance translational research in this field. Leading experts with diverse experience in both laboratory and patient-oriented research reviewed selected areas of pediatric lung diseases, including perinatal programming and epigenetic influences; mechanisms of lung injury, repair, and regeneration; pulmonary vascular disease (PVD); sleep and control of breathing; and the application of novel translational methods to enhance personalized medicine. This report summarizes the proceedings of this workshop and provides recommendations for emphasis on targeted areas for future investigation. The priority areas identified for research in pediatric pulmonary diseases included: (1) epigenetic and environmental influences on lung development that program pediatric lung diseases, (2) injury, regeneration, and repair in the developing lung, (3) PVD in children, (4) development and adaptation of ventilatory responses to postnatal life, (5) nonatopic wheezing: aberrant large airway development or injury? (6) strategies to improve assessment, diagnosis, and treatment of pediatric respiratory diseases, and (7) predictive and personalized medicine for children.
-
Pediatric pulmonology · Jan 2009
Sequential changes of hemodynamics and blood gases in newborn piglets with developing pneumothorax.
Little information is available regarding the temporal changes in hemodynamics and blood gases during the development of a moderate pneumothorax in a neonate. In this study, we aim to investigate the temporal changes of hemodynamics and arterial blood gases in a neonatal swine model of unilateral pneumothorax. ⋯ Deterioration in oxygenation was noted early in the development of pneumothorax in newborn piglets followed by metabolic acidosis. CVP progressively increased despite the lack of significant changes in systemic hemodynamics when moderate pneumothorax developed. Although CCAF increased during a moderate pneumothorax, carotid oxygen delivery decreased.
-
Pediatric pulmonology · Nov 2008
Prospective assessment of protracted bacterial bronchitis: airway inflammation and innate immune activation.
Protracted bacterial bronchitis (PBB) is a common cause of paediatric chronic moist cough. PBB is defined as the presence of isolated chronic moist cough which resolves with antibiotic therapy within 2 weeks and an absence of pointers suggesting alternative diagnoses. Our aim was to describe the clinical profile and examine the airway cellularity and likely promoters of neutrophilic inflammation in the bronchoalveolar lavage (BAL) of children with PBB compared with chronic cough due to other causes and controls. ⋯ Children with PBB had marked airway neutrophilia and increased median cytokine levels when compared to those with cough that resolved naturally and no cough controls: IL-8 0.67 versus 0.07 and 0.06 ng/ml (P < 0.005) and active MMP-9 7.25 versus 1.35 and 0.38 ng/ml (P < 0.005). The values for TLR-2 and TLR-4 mRNA expression were significantly elevated in children with PBB when compared to the control group. PBB is a paediatric condition which presents with chronic moist cough and its airway profile is characterized by intense neutrophilic airway inflammation with marked inflammatory mediator response and evidence of innate immune activation.
-
Pediatric pulmonology · Nov 2008
Measurement of maximal inspiratory pressure in ventilated children.
Maximal inspiratory pressure (PIMAX), the maximum negative pressure generated during temporary occlusion of the airway, is commonly used to measure inspiratory muscle strength in mechanically ventilated infants and children. There are, however, no guidelines as to how the PIMAX measurement should be made. We compared the maximum inspiratory pressure generated during airway occlusion (PIMAX(OCC)) to that when a unidirectional valve (PIMAX(UNI)), which allowed expiration, but not inspiration was used. ⋯ Regardless of technique, PIMAX was reached in 10 inspiratory efforts or 15 sec of airway occlusion. A unidirectional valve allowing expiration, but not inspiration yields greater PIMAX values in children. Occlusions should be maintained for 12 sec or eight breaths (99% CI of mean).