08.14 - Respiratory, Ventilatory Failure (Muthiah) - Questions Flashcards
__ is what actually drives breathing, via ___
PCO2, via hydrogen ions
High CO2 receptors at baseline means you’re workin on ___
Hypoxic Drive
Peripheral Chemoreceptors are primarily driven by ____
PaCO2 dissolved in plasma
PaCO2 levels in ARDS
If anything, hypocapnea: Hypoxemia driving hyperventilation
PaCO2 levels in COPD
Hypercapnea: Obstruction traps/retains CO2
PaCO2 levels in Pulmonary Fibrosis
Gradual so no Hyper or Hypo-capnea
Ventilatory Failure specifically means
Patient retaining CO2
Respiratory Failure means
Hypoxemia and Hypercapnea
Most patients with hypercapnic failure also have
hyperoxemic failure
Most common mechanism behind hypoxemic failure
V/Q Mismatch
Physiologic Shunt
5%
ARDS is a classic example of pure
Shunt
Heart defects are what classification of Hypoxemic mechanism
Shunt
Blood arriving at lungs is usually __ O2 sat
70%
Lower mixed venous O2 sat =>
Lower arterial O2 sat
2 Causes of lower mixed venous O2
Incr O2 extraction: Exercise and Infection
Dead Space Ventilation means there is no
Perfusion at ventilated alveoli
2 Mechanisms of Hypercapnic Failure
Decreased minute ventilation relative to demand; Incr dead space ventilation
Normal A-a gradient rules out
Intrinsic lung disease
When A-a gradient is widened, there is something wrong with
Lungs
__ readily corrects with supp O2, ___ does not
V/Q mismatch, Shunt does not
5 Causes of Hypoxemia
Decr PiO2; Hypoventilation; V/Q mismatch; Shunt; Diffusion limitation
4 causes of Hypercapnic Resp Failure:
Central Hypovent; Neuropathies; Muscle failure; Airway Obstruction
3 causes of O2 curve shift to right
Temp, Acidosis, Phosphate-2,3-DPG
3 Causes of O2 curve shift to left:
Low temp, Alkalosis, Fetal Hb
If patient presents with hypotension, suspect:
infection
Fifth Vital Sign
Pulse Oximetry
3 Drug Classes to Tx Bronchospasm
Beta 2 Agonist; Anti-cholinergic; LABA’s
Time to onset of Beta 2 Agonists and Anti-cholinergics
Both about 5-15 minutes
