tags:
  - paeds/respi/extra

Ventilatory support & assessing ventilation

1. High flow humidified oxygen

flow via a tight nasal cannula (Airvo or Optiflow)
this delivers air and oxygen continuously with some added pressure blown in through that tight nasal cannula that helps to oxygenate the lungs and prevent the lungs from collapsing
it adds 'Positive End Expiratory Pressure' (PEEP) to maintain the airway at the end of expiration and stop the airways from collapsing

2. Continuous Positive Airway Pressure (CPAP)

involves using a sealed nasal cannula that goes into the nose and performs in a similar way to the Airvo or the Optiflow but it can deliver higher and more controlled pressures

3. Intubation and ventilation

this is the final step of ventilatory support
this involves inserting an endotracheal tube into the trachea and fully controlling ventilation

Assessing ventilation

Capillary blood gases are useful in severe respiratory distress and in monitoring children who are having ventilatory support. The most helpful signs of poor ventilation are a rising pCO2. The CO2 level is going up and this shows that the airway have collapsed and are failing to clear waste carbon dioxide from the lungs. A falling pH shows that carbon dioxide is building up and the baby is not able to buffer the acidosis that is caused by the excessive carbon dioxide. Remember carbon dioxide becomes carbonic acid and is acidic. Which means the blood becomes acidic if it can't be buffered. This is classed as a respiratory acidosis. If the baby is also hypoxic meaning they've got a low level of oxygen this is classed as a type 2 respiratory failure.

However remember that if you're taking a capillary blood gas that's not going to show an accurate oxygen level because you need an arterial sample (ABG) to get an accurate oxygen level.