Acute Respiratory Failure Flashcards
Pulse oximetry
Measures amount of hemoglobin that is bound to oxygen (saturation percentage)
Normal is 94% or better
Goal in respiratory distress/failure is to get pulse ox at 90% of better
Oxygen delivery ways
Nasal cannula
- adult flow rates are between 1-6L
- adding 1 liter increases FIO2 by 4%, starting at 21% (i.e 4L of room air oxygen = 21+ 16 = 37%)
- use for mildly hypoxic
Non-rebreather mask
- used usually if patients oxy sat rates don’t increase to stable levels after 6L
- FIO2 is approximately 70% with this bag (varies based on seal of the bag)
Respiratory failure
Defined as inadequate gas exchange due to malfunction of one or more components of respiratory system
Two main types
1) hypoxemia
2) hypercapnic
* note a patient can have both simultaneously*
Signs/symptoms
- mental altered status
- extreme fatigue
- Cyanosis
- bad ABG values
- accessory muscle use and supraclavicular retraction
Hypoxemia respiratory failure
ABG saturation of less than 90% while received ing increased inspired oxygen
Caused by Impaired alveolar diffusion via inflammation or fibrosis development along the alveolar membrane
Causes = pneumonia, ARDS, PE, pulmonary edema, alveolar hemorrhage
Treatment:
- treat underlying issue
- increase oxygen given (both total Liters and type of device)
- CPAP and BiPAP is most common
- endotracheal tube is required if they cant breath on their own due to altered mental status/constant vomiting, GCS <8 or complete apnea is seen.
Hypercapnic respiratory failure
Unable to ventilate alveoli
- PaCO2 will be > 45mmHg
Results in respiratory acidosis
- every increase in 10 with PaCO2, pH will decrease by 0,08 (vise verse in alkalosis)
Causes =
- Drug OD
- obstructive COPD
- aspiration of foreign bodies
- neuromuscular diseases (MS and muscular dystrophy are most common)
- flail chest
- strokes