Non-Invasive Ventilation Flashcards
What are some limitations of non-invasive ventilation?
- Narrow range of patients
- Mode limitations
- Pressure and support level limitations
- Adjunctive treatments
What are some advantages of NIV?
- Decreased probability of intubation
- Decrease in nosocomial infections
- Decrease in sedation use
- Improved mobilization
- Improved ability to talk and communicate
Overall decrease in mortality and morbidity, time in ICU and hospital
What are some indications for use of NIV?
- Elevated work of breathing
- Poor oxygenation
- Inadequate ventilation
- Tachypnea
- Respiratory acidosis
- Acute or unresponsive hypoxemia
What are some contraindications for NIV?
- Impending respiratory failure
- Acute medical instability
- Uncooperative patient
- Decreased level of consciousness
- High aspiration risk
- Upper airway obstruction or lesion
- Unable to fit mask due to trauma, surgery, etc.
- Copious secretions
What are some interface problems?
Leaks from poor mask fit
What is the safe pressure limit for NIV and why?
20 cmH2O because it is the esophageal opening pressure. If we go above we risk putting air into the stomach
What is the difference between a single and dual limb circuit?
A dual limb has inspiratory and expiratory circuits; a single limb has only an inspiratory so the mask will have an anti-suffocation valve
Describe how NIV with a single-limb circuit works?
Has continuous flow which is adjusted to maintain set pressure. A drop in pressure reads as an inspiratory effort so the vent adjusts accordingly
When is non-invasive pressure control used?
- in “do not intubate” scenarios
- apneic or erratic drive to breath
- glottis opens fully on inspiration, may be ventilating against a closed glottis
What should CPAP level be set at?
5-15 cmH2O
Describe how BiPAP/BiLevel works?
EPAP: PEEP
IPAP: inspiratory positive airway pressure
Similar to pressure support
What is AVAPS?
Average volume assured pressure support
“Volume support” mode only available on the V60. We set Vt and pressure range. Pressure is adjusted by 1 cmH2O every minute based on patient effort
When would we and would we not use AVAPS?
Not for acute patients or patients severely SOB. Works well for neuromuscular disorders or nocturnal hypoventilation, gives better alveolar ventilation
What is PPV
similar to PAV but on V60 vent
