Module 4: Non-invasive Respiratory Support Flashcards
What are 4 goals of respiratory support?
- to achieve and maintain adequate pulmonary gas exchange
- to minimize the risk of lung injury
- to reduce patient work of breathing (WOB)
- to optimize patient comfort
What are the effects of non-invasive respiratory support (NIRS)? (4)
Decreased intrapulmonary shunting (ventilation/perfusion miss match).
Increased compliance and functional residual capacity and prevention of atelectasis
Recruits additional alveoli and splints the airways
Improved oxygenation
Decreased thoracoabdominal asynchrony
Decreased obstructive and mixed apnea
Conservation of surfactant
Improved lung growth
What are the mechanism of non invasive respiratory support (NIRS)?
Recruits additional alveoli, decreases pulmonary vascular resistance
Decreases pulmonary vascular resistance
Splints the airways and diaphragm, stabilizes chest wall
Supports and slows respiratory rate
Recruits alveoli, improves pulmonary blood flow, improves oxygenation
Stretches lung tissue
What does infants need to be suitable for NIRS?
- respiratory drive is intact,
- but who have difficulty with maintaining ventilation due to stiff lungs (RDS, atelectasis, BPD) or energy-related issues
What conditions where non invasive respiratory support (NIRS) is contraindicated (5)?
Respiratory failure defined as pH < 7.25, pCO2 > 60 (acidosis and hypercapnia)
Congenital malformations of the upper airway (T-E fistula, E.g. choanal atresia, cleft palate)
Congenital diaphragmatic hernia, bowel obstruction, omphalocele, or gastroschisis
Severe cardiovascular instability
Poor respiratory drive
What does CPAP stand for?
Continuous Positive Airway Pressure
What is CPAP?
CPAP applies positive pressure to the airways of the spontaneously breathing infant during inhalation and expiration.
CPAP is a form of respiratory support that provides a small amount of continuous flow, or a constant pressure, to the lungs.
This small amount of pressure works to keep the alveoli open at the end of expiration, maintaining lung volumes and assisting in alveolar recruitment.
Are neonates nose or mouth breathers?
- neonates are preferential nose breathers,
- which easily facilitates the application of nasal CPAP.
How is CPAP given to neonates?
- This is accomplished by affixing nasal prongs or fitting a nasal mask to the infant.
- The device provides heated and humidified continuous flow from a circuit connected to a continuous gas source, mechanical ventilator designed for neonates, or a suitably equipped multipurpose ventilator - set in Non-Invasive Ventilation CPAP mode.
What happens when CPAP maintain expiratory pressure (3)?
- in an increase in functional residual capacity (FRC) and
- improvement in lung compliance, and
- decreased airway resistance in the infant with unstable lung mechanics.
- This allows a greater tidal volume with subsequent reduction in the work of breathing and stabilization of minute ventilation.
What is MAP?
- mean airway pressure (MAP)
- the average pressure in the lungs during one complete breath, including inspiration and expiration
What are the 4 necessary parts to any CPAP system?
- A source of flow to create positive pressure
- The interface component that connects the CPAP to the neonate (prongs or mask)
- The driving force or method of positive pressure generation in the CPAP circuit, which includes the flow meter as an oxygen source and a blender or a ventilator to determine fraction of inspired oxygen (FiO2)
- The humidity and heating system.
What are 3 ways CPAP can be delivered?
- by nasal ET tube placed no deeper than the nasopharynx,
- nasal prongs, or
- a tight-fitting mask.
What are the 3 main types of CPAP?
- continuous flow CPAP,
- Variable Flow CPAP, and
- Bubble CPAP
What are two ways to supply positive airway pressure to neonate in respiratory distress?
- constant airway pressure
- variable airway pressure
What is constant airway pressure?
- airway pressure is achieved when a continuous flow creates the pressure determined by the CPAP setting on the respiratory device being used.
- The amount of flow will create the continuous positive pressure generated and applied to the lungs
What are the two ways nasal cannula supply positive pressure?
- low flow nasal cannula (LFNC)
- Fisher & Paykel OptiV-Flow Jr. : Heated and humidified high flow nasal cannula is a simple, noninvasive method of oxygen delivery that can produce positive pressure in a premature infant. This device requires a 50% leak around the prongs to allow for C02 clearance.