Non-Invasive Ventilation Flashcards
When is non-invasive ventilation used?
Non-invasive ventilation is used as an alternative to full intubation and ventilation to support the lungs in respiratory failure due to obstructive lung disease.
What is the difference between full intubation & ventilation and non-invasive ventilation?
Intubation and ventilation involves giving the patient a general anaesthetic, putting a plastic tube into the trachea and ventilating the lungs artificially.
Non-invasive ventilation involves using a full face mask or a tight fitting nasal mask to blow air forcefully into the lungs and ventilate them without having to intubate them.
What are the two types of non-invasive ventilation?
BiPAP or CPAP
What is BiPAP?
Bilevel positive airway pressure
What does BiPAP involve?
This involves a cycle of high and low pressure to correspond to the patients inspiration and expiration.
With what type of respiratory failure uses BiPAP?
BiPAP is used where there is type 2 respiratory failure, typically due to COPD.
What is the criteria for using BiPAP?
Respiratory acidosis (pH < 7.35, PaCO2 >6) despite adequate medical treatment.
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What are the contraindications of BiPAP?
Untreated pneumothorax or any structural abnormality or pathology affecting the face, airway or GI tract.
What steps should be taken when considering NIV
Patients should have a chest Xray prior to NIV to exclude pneumothorax where this does not cause a delay.
A plan should be in place in case the NIV fails so that everyone agrees whether the patient should proceed to intubuation and ventilation and ICU or whether palliative care is more appropriate.
Define IPAP
IPAP (inspiratory positive airway pressure) is the pressure during inspiration. This is where air is forced into the lungs.
Define EPAP
EPAP (expiratory positive airway pressure) is the pressure during expiration. This provides some pressure during expiration so that the airways don’t collapse and it helps air to escape the lungs in patients with obstructive lung disease.
Starting points for BiPAP for an average male patient might be…
The initial pressures are estimated based on the patients body mass and measured in cm of water. Potential starting points for an average male patient might be:
IPAP 16-20cm H2O
EPAP 4-6cm H2O
How often should you repeat an Arterial Blood Gas test after BiPAP?
Repeat an ABG 1 hour after every change and 4 hours after that until stable. The IPAP is increased by 2-5 cm increments until the acidosis resolves.
What is CPAP?
CPAP stands for continuous positive airway pressure.
It provides continuous air being blown into the lungs that keeps the airways expanded so that air can more easily travel in and out.
It is used to maintain the patient’s airway in conditions where it is prone to collapse.
