Oxygen Delivery Devices & Stair Step Approach to Increasing O2
typical oxygen delivery devices
Fio2 per liter? (is general & not important)
1L .24 2L .28 3L .32
4L .36 5L .40 6L .44
Keep this in mind, from UC Denver Medical Schol:
"A given liter flow rate of nasal O2 does not = any specific FIO2. The oft-quoted rule that 2 l/min =an FIO2 of 24%, 3 l/min = 28%, etc., is an illusion, based on nothing experimental or scientific. The actual FIO2 with nasal oxygen depends on the patient's breathing rate and tidal volume, i.e., the amount of room air inhaled through the mouth and nose that mixes with the supplemental oxygen."
venturi mask Basic Info
Used when more O2 is needed than can be delivered from nasal cannula
Fio2 per liter?
More important: What is the trend of O2 needs? And, is the patient getting better, staying the same, or getting worse?
partial/non re-breather mask Basic Info
Partial mask: has no valves on sides to prevent air being rebreathed
Non rebreather mask: has the valves, expired air can't be re-breathed
Used at 10-15L
how long can a non re-breather be used?
Typically, it is not left on very long (vague answer on purpose) usually <24hrs. Either it is weaned, or stepped up to a High Flow Nasal Cannula or CPAP/BiPAP so that FiO2 and flow are more precisely regulated
Why does it have a bag?
Acts as a resovoir, limits O2 loss during breathing. Some one on a NRB is requiring increased O2.
Flow must also be high enough to maintain an inflated bag.
cpap/bipap basic info
CPAP = Continuous Positive Airway Pressure pressure delivered
BiPAP= An inspiratory & an expiratory pressure (Bilevel Positive Airway Pressure)
Pressures and FiO2 are adjustable
Which is used, bipap or cpap?
To keep this basic:
CPAP: for sleep apnea and a lower pressure required to solve the oxygen need.
BiPAP: When higher pressures are needed (but a lower pressure can be used in order to exhale); when CPAP fails
CPAP / Bipap fact sheet
Stair step approach to increasing oxygen needs (needs a few seconds to load)
As a nurse, you will often be the first to realize that a patient needs increased oxygen and/or ventilatory support, so it is good to know what the logical sequence is in increasing these needs.
Additional Methods Used to Support Respiration/Ventilation
Inhaled nitric oxide
- The unit above (picture) is used in conjuction with a ventilator (set up by RT)
- Works to reduce pulmonary artery tone
- Lowers pulmonary vascular resistance, improving oxygenation
- Used in patient with:
- Acute lung injury
- Acute respiratory distress syndrome
- Acute pulmonary embolism
- Right ventricular heart failure
Important things to know as a nurse
- Needs to be weaned slowly (managed by RT)
- Fairly elaborate protocols exist for weaning FiO2 and iNO
- You may see iNO delivered at 20ppm (parts per million)
- Then 10ppm, then 5ppm, then 4, 3, 2, and 1
- Just because iNO can go from 20 to 10 quickly, does not mean iNO can go from 5 to 1 quickly
- RT sets up iNO. You need to make sure that the iNO flow is also connected to the AMBU bag in case you need to bag the patient
It is important to wean slowly because:
- Rebound hypertension can occur
- Hypoxemia can occur
This is related to supression of indogenous NO (our own NO) when receiving iNO (therapeutic NO)
- Thus it is important to have iNO flowing through AMBU bag in case bagging is necessasry
- Is a mixture of helium and oxygen
- Used in obstructive airway disease (increased airway resistance)
- The physical properties of Heliox decrease the resistance within the airways and thus helps to decrease the work of breathing
- Heliox mixture is less dense than air, resistance to its flow is much less