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Nasal Mask (nasal + mask)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Flow-dependent resistance of nasal masks used for non-invasive positive pressure ventilation

RESPIROLOGY, Issue 4 2006
Wolfram WINDISCH
Objective and background: Endotracheal tube resistance is known to be flow-dependent and this understanding has improved the application of invasive ventilation. However, similar physiological studies on the interface between patients and non-invasive positive pressure ventilation (NPPV) have not been performed. Therefore, this study was aimed at investigating the resistance of nasal masks used for NPPV. Methodology: The flow-dependent pressure drop of the small (S), medium-small (MS) and medium (M) Contour Nasal Mask (Respironics Inc., Murrysville, PA, USA) was measured with and without a connecting tube (length 18 cm, internal diameter 1.5 cm) in a laboratory study. The resistance was calculated by Rohrer's equation using the standard least-squares-fit technique. The present study explicitly differentiated between the resistance of the nasal mask alone when measured against atmosphere and the additional resistance caused by the nasal mask when airtightly fitted to a model head (interaction with the face). Results: Higher flow rates resulted in a non-linearly increasing pressure drop across the interface. This flow-dependent resistance of the S/MS/M mask was comparably low when not interacting with the face, but increased when interacting with the face. This flow-dependent resistance of the mask was several-fold higher when adding the connection tube and tended to be higher during expiration. Conclusion: There is a non-linear flow-dependent pressure drop across the nasal mask which is low and independent of its size, but increases when interacting with the face. The connecting tube is the major determinant of the resistance originating from facial appliances used for NPPV. [source]

Recurrent pneumothoraces associated with nocturnal noninvasive ventilation in a patient with muscular dystrophy

PEDIATRIC PULMONOLOGY, Issue 1 2002
Lee R. Choo-Kang MD
Abstract Although a common complication of mechanical ventilation in acute respiratory failure, spontaneous pneumothorax has been rarely reported among patients on chronic, intermittent, noninvasive positive pressure support. We report the first case of recurrent pneumothoraces associated with nocturnal bilevel positive airway pressure ventilation via a nasal mask. A 26-year old man with chronic respiratory failure secondary to an unclassified neuromuscular condition suffered four separate episodes of spontaneous pneumothorax over a 12-month period. Two episodes occurred while he was asleep on bilevel positive airway pressure support. He was found to have numerous subpleural blebs, and we propose a mechanism for their development. Following open pleurodesis and blebectomy, the patient has not had another pneumothorax. Given the increasing utilization of chronic nocturnal bilevel positive airway pressure ventilation, we suggest that healthcare providers and patients be made aware of this potentially life-threatening complication. Pediatr Pulmonol. 2002; 34:73,78. © 2002 Wiley-Liss, Inc. [source]

Home mechanical ventilation in children: Retrospective survey of a pediatric population

PEDIATRICS INTERNATIONAL, Issue 6 2007
GIANCARLO OTTONELLO
Abstract Background: Home care support is beneficial for children needing mechanical ventilation, when clinically stable. Methods: A retrospective analysis was carried out of the long-term home ventilation management of a pediatric population with chronic respiratory failure composed of 20 ventilator-dependent children categorized according to age, diagnosis and ventilation support. Age groups consisted of 10% under 1 year, 30% between 2 and 5 years, 30% between 6 and 12 years, and 30% older than 12 years. Diagnostic categories included myopathic disorder, n = 5; congenital central hypoventilation syndrome, n = 6; chest wall disorder, n = 5; cystic fibrosis, n = 1; pulmonary hypertension, n = 1; and diaphragmatic paralysis, n = 2. Results: Sixty-five percent were ventilated using non-invasive mode (NIMV): eight with nasal mask, five with full-face mask, and two children in NIMV also used negative pressure mode; 35% were ventilated using tracheostomy, one of them also used a diaphragmatic pacer. Seventy percent needed nocturnal ventilatory support, (20% 12,18 h, 10% full-day). A total of 18 children were included in the home care and follow-up program. Two children died: one because of worsening of his chronic disease and one because of septic shock. Conclusion: Although home care ventilation is not yet widely diffused, it represents a valid alternative to long hospitalization for children with stable chronic respiratory failure. [source]