THORACIC – TCAR QUESTION AND ANSWER
Blood supply upper 2/3 of trachea - ANSWER inferior thyroid arteries
Blood supply lower 2/3 of trachea - ANSWER bronchial arteries
Blood supply lung parenchyma - ANSWER bronchial arteries
Pathway of azygous vein in the thorax - ANSWER runs along R side and dumps into superior vena cava
Pathway of thoracic duct in the chest - ANSWER runs along R side, crosses midline at T4-T5, goes into L
neck and dumps into L subclavian vein at junction with LIJ
Pathway of phrenic nerve in thorax - ANSWER runs anterior to hilum
Pathway of vagus nerve in thorax - ANSWER runs posterior to hilum
What fissures exist in the lungs? - ANSWER Major oblique separates RLL from middle and upper lobe
Minor separates upper from middle lobe
Muscle used in quiet respiration - ANSWER Diaphragm 80%, intercostals 20%
Accessory muscles of respiration - ANSWER SCM
Levators
Serratus posterior
Scalenes
Main surface active agent in surfactant - ANSWER phosphatidylcholine
,Alveolar, arterial, and venous pressures in lung zones in upright person - ANSWER Zone I: PA > Pa > Pv
Zone II: Pa > PA > Pv
Zone III: Pa > Pv > PA
Normal pulmonary artery pressure - ANSWER 25/10 (mean 15)
What predicted value is needed for pulmonary resection? - ANSWER Predicted postop FEV1 > 0.8L (>40%
predicted)
What can be done if the predicted postop FEV1 is close to 0.8 (40% predicted)? - ANSWER Obtain a V/Q
scan and see how much that segment actually contributes
Single best predictor of being able to wean off ventilator after pulmonary resection - ANSWER FEV1
Minimum DLCO for lung resection - ANSWER >11-12 ml/min/mmHg CO (>50% predicted value)
What six things effect DLCO? - ANSWER Pulmonary capillary surface area
Hgb
Alveolar architecture
Dead space
Low CO
Pulmonary HTN
What pCO2 is necessary for lung resection? - ANSWER <45 at rest
What pO2 is necessary for lung resection? - ANSWER >60 at rest, not on O2
What VO2max is needed for lung resection? - ANSWER >10 ml/kg/min (maximum o2 consumption)
, Overall PFTs required for pulmonary resection - ANSWER FEV1 >0.8L (>40% predicted)
DLCO >11-12 ml/min/mmHg CO (>50% predicted, or 40% postop)
pCO2 <45 at rest
pO2 >60 at rest, not on O2
VO2 >10 ml/kg/min
MCC of hypoxemia after pulmonary resection - ANSWER V/Q mismatch from atelectasis (shunt)
MCC of hypercarbia after pulmonary resection - ANSWER alveolar hypoventilation (poor minute
ventilation RR x TV)
MC nerve injury after pulmonary resection - ANSWER brachial plexus injuries
How can common peroneal nerve injuries be avoided durin pulmonary resection? - ANSWER flex
dependent leg
Most common resection resulting in persistent air leak - ANSWER segmentectomy/wedge
MC resection resulting in atelectasis - ANSWER lobectomy
MC resection resulting in arrhythmias - ANSWER pneumonectomy (R MC)
MC resection resulting in postop TEF - ANSWER pneumonectomy (R MC)
MC resection resulting in postop bronchopleural fistula - ANSWER pneumonectomy (R MC)
MC resection resulting in mortality - ANSWER pneumonectomy (R MC)
Blood supply upper 2/3 of trachea - ANSWER inferior thyroid arteries
Blood supply lower 2/3 of trachea - ANSWER bronchial arteries
Blood supply lung parenchyma - ANSWER bronchial arteries
Pathway of azygous vein in the thorax - ANSWER runs along R side and dumps into superior vena cava
Pathway of thoracic duct in the chest - ANSWER runs along R side, crosses midline at T4-T5, goes into L
neck and dumps into L subclavian vein at junction with LIJ
Pathway of phrenic nerve in thorax - ANSWER runs anterior to hilum
Pathway of vagus nerve in thorax - ANSWER runs posterior to hilum
What fissures exist in the lungs? - ANSWER Major oblique separates RLL from middle and upper lobe
Minor separates upper from middle lobe
Muscle used in quiet respiration - ANSWER Diaphragm 80%, intercostals 20%
Accessory muscles of respiration - ANSWER SCM
Levators
Serratus posterior
Scalenes
Main surface active agent in surfactant - ANSWER phosphatidylcholine
,Alveolar, arterial, and venous pressures in lung zones in upright person - ANSWER Zone I: PA > Pa > Pv
Zone II: Pa > PA > Pv
Zone III: Pa > Pv > PA
Normal pulmonary artery pressure - ANSWER 25/10 (mean 15)
What predicted value is needed for pulmonary resection? - ANSWER Predicted postop FEV1 > 0.8L (>40%
predicted)
What can be done if the predicted postop FEV1 is close to 0.8 (40% predicted)? - ANSWER Obtain a V/Q
scan and see how much that segment actually contributes
Single best predictor of being able to wean off ventilator after pulmonary resection - ANSWER FEV1
Minimum DLCO for lung resection - ANSWER >11-12 ml/min/mmHg CO (>50% predicted value)
What six things effect DLCO? - ANSWER Pulmonary capillary surface area
Hgb
Alveolar architecture
Dead space
Low CO
Pulmonary HTN
What pCO2 is necessary for lung resection? - ANSWER <45 at rest
What pO2 is necessary for lung resection? - ANSWER >60 at rest, not on O2
What VO2max is needed for lung resection? - ANSWER >10 ml/kg/min (maximum o2 consumption)
, Overall PFTs required for pulmonary resection - ANSWER FEV1 >0.8L (>40% predicted)
DLCO >11-12 ml/min/mmHg CO (>50% predicted, or 40% postop)
pCO2 <45 at rest
pO2 >60 at rest, not on O2
VO2 >10 ml/kg/min
MCC of hypoxemia after pulmonary resection - ANSWER V/Q mismatch from atelectasis (shunt)
MCC of hypercarbia after pulmonary resection - ANSWER alveolar hypoventilation (poor minute
ventilation RR x TV)
MC nerve injury after pulmonary resection - ANSWER brachial plexus injuries
How can common peroneal nerve injuries be avoided durin pulmonary resection? - ANSWER flex
dependent leg
Most common resection resulting in persistent air leak - ANSWER segmentectomy/wedge
MC resection resulting in atelectasis - ANSWER lobectomy
MC resection resulting in arrhythmias - ANSWER pneumonectomy (R MC)
MC resection resulting in postop TEF - ANSWER pneumonectomy (R MC)
MC resection resulting in postop bronchopleural fistula - ANSWER pneumonectomy (R MC)
MC resection resulting in mortality - ANSWER pneumonectomy (R MC)
