Acute Respiratory Failure & ARDS Flashcards
1
Q
Types of respiratory failure
A
- hypoxemic
- hypercapneic
2
Q
Characteristics of hypoxemic respiratory
A
- respiratory failure due to inadequate oxygenation
- cause: any process that impairs oxygen transport across alveolar/capillary barrier
3
Q
Examples of hypoxemic respiratory failure
A
- alveolar filling processes:
- LHF w/pulmonary edema
- pneumonia
- alveolar hemorrhage
- ARDS
- extra-alveolar proccesses:
- pulmonary vascular disease
- shunt
4
Q
Characteristics of hypercapneic respiratory failure
A
- due to inadequate ventilation/inadequate CO2 removal
- caused by any process that impairs ventilation
- e.g. obstructive lung disease, restrictive lung disease, central hypoventilation
5
Q
Four parameters for managing patients on the ventilator
A
- FIO2 - the fraction of inspired oxygen between 21% (room air) and 100% (pure oxygen.
- PEEP - Positive end-expiratory pressure.
- Respiratory rate
- Tidal volume
- Ventilation (minute) = RR x TV
- increase these to increase ventilation
- Oxygenation determinants = FIO2 & PEEP
- increase these to increase oxygenation
6
Q
Dx criteria for ALI/ARDS
A
- “Acute Lung Injury”/”Acute Respiratory Distress Syndrome”
- Diffuse bilateral radiographic infiltrates
- PaO2:FIO2 ratio < 300(ALI) or <200(ARDS)
- No evidence of a cardiogenic etiology (e.g. LHF)
7
Q
Characteristics of ARDS + common causes
A
- intense alveolar inflammation w/increased pulmonary capillary permeability ==>
- neutrophil influx, epithelial cell damage/death, alveolar flooding, hyaline membrane deposition, hemmorhage
- predisposition: inflammation
- common causes:
- sepsis
- pancreatitis
- trauma
- aspiration
- transfusion
8
Q
Strategies for management of ARDS to improve survival
A
- ARMA trial ==> low tidal volumes = only successful tx to increase survival
- 6 cc/kg = better volume (vs. 12 cc/kg)
- continue low volumes even if pt develops hypercapnea and respiratory acidosis = “permissive hypercapnea”
