AIRWAY AND 02 SKILL SHEET Flashcards
PEEP improves oxygenation, improves ventilation and reduces the workload of breathing, via the following physiological effects:
> The expiratory pressure assists small and medium sized airways to remain open during expiration, preventing lung collapse. Once collapsed, significant additional pressure is required to re- expand them.
The positive pressure in the thoracic cavity reduces the preload (filling) of the right ventricle by reducing venous return to the heart (this will be further compounded by GTN administration).
The positive pressure in the thoracic cavity increases the afterload of the right ventricle. This reduces blood flow through lung vessels, reducing the amount of fluid entering the lungs.
The expiratory pressure increases the amount of air remaining in the lungs at the end of expiration (also called the functional residual capacity) and this causes the lungs to be more expanded. From this more expanded resting position, less work
is required to inspire as a result of the non-linear compliance of the lungs, particularly when the lungs are wet.
PEEP Indications
> When a manual ventilation bag is being used to provide ventilation.
Cardiogenic pulmonary oedema if CPAP is indicated but unavailable.
PEEP Contraindications:
> Cardiac arrest for an adult or child (excludes neonates).
PEEP Cautions:
– Ventilation is occurring via an ETT or LMA and the patient has signs of shock.
– PEEP is being applied using a manual ventilation bag and mask, and the patient has an altered level of consciousness, vomiting or signs of shock.
PEEP setting for cardiogenic pulmonary oedema
> Apply PEEP set to 10 cmH2O. Do not assist with the patient’s breathing unless it is ineffective.
Increase the PEEP to 15 cmH2O if the patient is not improving
PEEP for neonate
Apply PEEP set to 5 cmH2O, including during cardiac arrest.
PEEP for child
Do NOT attach PEEP during cardiac arrest
> Apply PEEP set to 5 cmH2O for all other conditions
PEEP for adult
> Do NOT attach PEEP during cardiac arrest
Apply PEEP set to 5 cmH2O if the patient has TBI, COPD, asthma or signs of shock
Apply PEEP set to 10 cmH2O for all other conditions
PEEP increases intracranial pressure in patients with TBI by
reducing venous return from the brain. In this setting, there is a balance between the benefit of PEEP improving oxygenation and the risk of PEEP increasing intracranial pressure. This is why PEEP is set to 5cm H2O for these patients.
PEEP is not applied to adults and children during CPR because
an increase in intrathoracic pressure reduces the blood flow achieved during CPR. If ROSC is achieved it is appropriate to apply PEEP, but this is not an immediate priority.
flow rate and indication for nasal prongs
1-4L/min
when patient requires minimal 02, chronic respiratory condition or won’t tolerate a mask
flow rate and indication for simple mask
6-8L/min
breathing adequate, needs support 02
flow rate and indication for reservoir mask
10-15 L/min
breathing adequate, requires high flow 02 such as deacersed LOC or extremely low 02
flow rate and indication for BVM
breathing absent, inadequate 10/15L/min
what happens when 02 is administered
02 is a vasoconstrctor, causing less perfusion to tissue and organs, it can also increase inflammation AND BP
indication for 02
-airway obstruction
-resp distress
severe shock
-severe TBI
- less than 94% ORA
The physiological effects of CPAP
A The positive pressure assists small and medium sized airways to remain open during expiration, reducing lung collapse. This also may aid expiration in patients with bronchospasm by reducing dynamic hyperinflation.
A The positive pressure during inspiration means that less work is required, reducing the work of breathing.
A The positive pressure in the thoracic cavity reduces the preload (filling) of the right ventricle by reducing venous return to the heart.
A The positive pressure in the thoracic cavity increases the afterload of the right ventricle. This reduces blood flow through lung vessels, reducing the amount of fluid entering the lungs.
A The expiratory pressure increases the amount of air remaining in the lungs at the end of expiration (the functional residual capacity) and this causes the lungs to be more expanded. From this more expanded resting position, less work is required for inspiration because of the non-linear compliance of the lungs, particularly when the lungs are wet.
A CPAP allows the clinician to postpone or prevent invasive techniques in patients who present with acute respiratory failure.
Indications of CPAP
A Cardiogenic pulmonary oedema with moderate to severe respiratory distress,
or
A Asthma, COPD, or undifferentiated respiratory problem with severe respiratory distress that is not improving with treatment,
or
A An SpO2 of less than 92% due to a respiratory problem despite treatment (less than 88% if COPD or known chronic hypoxia).
CPAP contrindications
A Active vomiting, or
A Ineffective breathing.
CPAP cautions
A An altered level of consciousness, or A Signs of shock, or
A Clinical suspicion of pneumothorax.
CPAP reduces cardiac output and should be used with caution in patients showing signs of shock. The reduction in cardiac output may be significant in patients with:
– A clinical condition reducing right ventricular filling, such as hypovolaemia.
– A clinical condition increasing right ventricular afterload, such as pulmonary embolism.
possible complications of CPAP
A Mask seal
A Tolerance/anxiety
A Reduced cardiac output.
medical air indication
Medical air (air) is indicated when administering nebulised bronchodilators to patients with chronic obstructive pulmonary disease (COPD).
OPA indication
OPAs should be routinely placed in patients requiring airway support unless there is a good reason not to.