Study guide flashcards
when dealing with a mediastinal mass what type of intubation should you plan on
fiberoptic, spontaneous respiration
cause of leakage in lungs after thoracotomy
inflammatory mediators at alveolar-endothelial barrier
ALI - what causes stretching of capillaries?
fluid overload causes failure of micro vessels, disturbing permeability
Which side lung lobectomy is better tolerated and why
L lobectomy better tolerated because R lung is bigger and has more blood flow and oxygenation
What can occur during mediastinoscopy (besides hemorrhage and pneumo)
how/why?
Pressure on innominate artery–>decreased cerebral blood flow
reduces flow flow to:
R common carotid
R vertebral
Subclavian flow to R arm
How do we prevent/monitor for too much pressure on innominant artery
- Pulse ox and/or art line on R arm
- BP cuff on L to prevent interruption of R readings
In restrictive lung disease, there is a decrease in
All lung volumes and capacities
In obstructive lung disease, there is an increase in
RV, FRC, TLC
Dominant feature of obstructive lung disease/COPD
progressive airflow obstruction
Increased FRC, RV, TLC
What scenario causes the largest VQ mismatch?
Anesthetized, vented, paralyzed, one lung down, open chest
HPV is triggered by
alveolar hypoxemia
HPV only occurs in
pulmonary circulation
in regular circulation, hypoxemia causes vasodilation
HPV in OLV decreases blood flow by (amount)
50%
Blood flow in HPV (lung ratio)
80:20 instead of 60:40
Potential complicatino with inflating bronchial cuff
bronchial rupture form overinflation
1-3 mL of air in bronchial cuff
Bronchial lumen and RUL
Can obstruct more easily:
Carina to RUL: 2.5 cm compared to
Carina to LUL: 4-5 cm
consider using L DLT for R and L deflations unless there is a contraindication
Main anesthetic goal in OLV
maintain adequate oxygenation. wile maintaining visualization of lungs for surgeon
Hypoxemia in OLV
- 100% FiO2
- check tube placement
- CPAP
- PEEP
- Early PA ligation (if planned)
- resume 2 lung ventilation
Following re-expansion of lung, be sure to
deflate bronchial cuff - avoids bronchial ischemia
PA catheter and R lung collapse
PA will not give accurate readings
Monitor placement for OLV
- art line on dependent arm for stabilization
- BP cuff on non-dependent arm to avoid interruption
Thoracic surgery pt optimization best:
Cessation of smoking
Within 2 months of cessation of smoking:
increased secretions –> increased complications
but patients with lung cancer should not wait longer than 2 months
Assessing risk for thoracic surgery PFTs
Need PPO FEV1 (predicted post op FEV1)
traditional FEV1 is not enough
calculates traditional FEV1 by fraction of functioning lung or DLCO
Diffusion capacity abbreviation
DLCO
DLCO - what does it do
howcan in indicated complications
measures ability to transport gas across alveolar-capillary membrane
<60% = increased complications
ABGs and predicting post op complications
SpO2 < 90% on RA is indicative of postop complication
IF PPO FEV1 is <40%:
additional screening is needed
DLCO
V/Q scan
VO2 max
What do high risk candidates look like for thoracic surgery:
FEV1
PPO FEV1
DLCO
VO2 max
Stairs
Oxygen desaturation
FEV1: <2L or < 40% predicted
PPO FEV1: <40%
DLCO: <40% predicted
VO2 max: < 10 mL/kg/min
Stairs: inability to climb one flight of stairs
O2 sats: desaturation >4% during exercise
Most effective analgesia for thoracic surgery:
Thoracic epidural T6 - T8
*does not decrease HPV
What increases bullae?
- N2O
2.PPV
Vt and rate with bullae
PIP gal
small Vt and faster RR
goal to keep PIP below 10-20 cm H2O
PIP goal with bullae
below 10-20 cm H2O
