Respiratory Flashcards
Triggers the end of inspiration by inhibiting the DRG.
Strong stimulus: rapid shallow breathing
Weak stimulus: slow and deep breathing
Pneumotaxic center
Antagonizes pneumotaxic center which causes inspiration
(Stimulates DRG)
Apneustic center
What inhibits the apneustic center?
Pulmonary stretch receptors (J receptors)
Causes inspiration (respiratory pacemaker)
Dorsal respiratory group
Causes expiration
Ventral respiratory group
____ drives the respiratory pacemaker in the DRG
H+
______ concentration in the CSF is the most important stimulus for the central chemoreceptor
Hydrogen ion
What drugs can be given down the ETT?
NAVEL:
Narcan
Atropine
Vasopressin
Epi
Lidocaine
In a patient undergoing pneumonectomy with OLV, crystalloid administration should be limited to?
< 3L in 24 hrs
Tracheal cuff pressure should be less than ___?
25 cmH20
How much cricoid pressure awake and after LOC?
Awake: 20 newtons ~ 2kg
After LOC: 40 newtons ~ 4kg
Peds ETT w/o cuff?
(Age/4) + 4
Peds ETT w/ cuff
(Age/4) + 3.5
Peds ETT depth
Internal diameter x 3
Max cuff pressure of LMA (not PPV pressure)
60 cmH20 (target = 40-60)
Anterior epiglottis supplied by:
Posterior epiglottis supplied by:
Glossopharyngeal (CN IX)
SLN (internal branch CN X)
Which pulmonary function test is the MOST sensitive indicator of small airway disease (obstruction)?
Forced expiratory flow at 25-75% vital capacity
Volume of air that can be exhaled after a maximal inhalation.
Normal value?
FVC
Male= 4.8L
Female= 3.7L
What FEV1/FVC ratio suggests obstructive dz?
<70%
(Normal with restrictive)
Normal value of DLCO
17-25 ml/min/mmHg
Which drugs increase PVR?
Nitrous oxide, ketamine, Desflurane
How does carbon monoxide affect the pulse ox?
May give a falsely elevated result
What color is the pt with carbon monoxide poisoning?
cherry red appearance (not cyanotic)
How does O2 supplementation affect carboxyhemoglobin?
Reduces t1/2 from 4-6 hrs on room air to 60-90 min with 100% O2. (O2 therapy continued until CoHgb < 5% or for 6 hrs)
When is hyperbaric O2 needed for CO poisoning?
CoHgb > 25% or the pt is symptomatic
What is the risk of carbon monoxide formation with soda lime greatest to least?
Des > Iso»_space;» Sevo
Strong indications for mechanical ventilation
Vital capacity < 15mL/kg
Inspiratory force < 25 cmH2O
PaO2 < 200 mmHg (on 100% FiO2)
A-a gradient > 450 mmHg (on 100% FiO2)
PaCO2 > 60 mmHg
RR > 40 or < 6 bpm
bronchopleural fistula & pulmonary infection
What are the best predictors of post pulmonary complications for pts undergoing pulmonary surgery?
FEV1 < 40% predicted
DLCO < 40% predicted
VO2 max < 15mL/kg/min
What is the youngest age you can use a DLT? What size?
8-9 yrs
26F
What is the hallmark of ARDS?
hypoxemia despite increased supplemental oxygen
What tidal volumes do we use for ARDS?
4-6 mL/kg (normal 6-8 mL/kg)
What is the most common pulmonary etiology of ARDS?
pneumonia
What is the most common extra-pulmonary etiology of ARDS?
sepsis
What variable is reduced by dynamic hyperinflation?
Inspiratory capacity
What lab value is a predictive marker for post-op pulmonary complications for non-thoracic surgery?
albumin
What technique is the gold standard for managing the difficult airway?
Flexible fiberoptic bronchoscope with patient awake and spontaneous ventilation
In general, increased dead space affects _____ and increased shunt affects _____
PaCO2; PaO2
