Thoracic Flashcards
How long is an adult trachea?
11-13cm
At what spine does an adult trachea begin?
C6
At what angles do the R & L bronchi diverge from the trachea?
R 25, L 45
How many lobes does each lung have?
R - 3, L - 2
What is the lateral distance of the upper lobes from the carina?
R - 1-2.5cm, L 5cm
Which bronchiole is smaller, the one leading to the right middle or right lower?
right lower, is 40:60 diameter split
Which are the true ribs? the false ribs? the floating ribs?
true (connect to sternum directly) - 1-7; false (connect to sternum via cartilage or don’t connect at all) - 8-12; floating (don’t connect to sternum) 11-12
In one-lung ventilation, which is the dependent lung?
the lung being ventilated
What is the ideal patient position during OLV?
lateral with dependent lung on the bottom (so that blood flows to it)
What is a normal PaO2?
80-100mmHg
What types of airways are available for one-lung ventilation?
DLT, single lumen w/ bronchial blocker, single lumen bronchial tube
What size DLT should a patient have?
female: 35 Fr < 63” ht < 37 Fr
male: 37-39 Fr < 67” ht < 41 Fr
What is the standard depth (at the teeth) of a DLT?
29cm
What are three disadvantages of the single-lumen tube with bronchial blocker?
- blocked lung collapses slowly
- doesn’t allow suctioning or ventilation of isolated lung
- catheter is easily dislodged
Which is the isolated lung?
the one not being ventilated
Which types of OLV tubes have the potential to cause the most trauma?
Carlen’s (with carinal hook)
What is one major advantage of the DLT?
ability to ventilate and suction either lung
Which types of OLV tubes can ventilate the isolated lung?
all except bronchial blocker
Which OLV tubes have the best success rate of ventilating RUL?
Robertshaw and Carlens because they have a slit in the bronchial cuff
What are absolute indications for OLV (3)?
- isolation of spillage or contamination
- bronchopleural fistula
- unilateral bronchopulmonary lavage
FEV1/FVC <__% is a high-risk post-op predictor.
50
Diffusing capacity <__% is a high-risk post-op predictor.
50
RV/TLC >__% is a high-risk post-op predictor.
50
PaCO2 >__mmHg is a high-risk post-op predictor
45
What does ppo FEV1 stand for?
prediction of post-op fractional expired volume in 1 second
How is ppo FEV1 calculated?
pre-op FEV % x (1 - % functional tissue removed/100)
What are the percent volumes of each lobe?
RUL 14%, RML 10%, RLL 29%, LUL 24%, LLL 24%
What are is one reason why the bottom lung in lateral decubitus would have smaller tidal volumes?
chest wall is constricted by bean bag holding patient in place
Under GA, why do tidal volumes decrease for both lungs?
with GA there is an increase in intra-abdominal pressure which decreases diaphragmatic movement
In upright or supine position, the right lung receives what percent of TBF?
55%
In lateral decubitus, the bottom lung receives what percent of TBF? Why?
60%; shunting (?)
What nerves are most likely to be injured during thoracic surgery?
vagus, phrenic, recurrent laryngeal (positioning [lateral] - brachial plexus)
HPV is triggered by what sensors? where?
O2 sensors in pulmonary artery smooth muscle cells
What anesthetic agents decrease HPV?
inhalationals at >1 MAC, vasodilators (including propofol and etomidate)
What notable anesthetic agents have to effect on HPV?
ketamine, morphine, fentanyl
How should hypoxemia in OLV be treated?
100% O2; manual ventilation; ventilate at 40mmHg; CPAP 5-10cmH2O to collapsed lung; PEEP to ventilated lung; continuous O2 to collapsed lung; clamp pulm artery of collapsed lung
Why is too much PEEP bad in OLV?
Increases shunting of blood to the collapsed lung
