Thoracic Surgery (Shannon) Flashcards
2 Important predictors of Post-op Complications:
Predicted postop FEV1 <40% of predicted
Predicted postop DLCO <40% of predicted
Thoracic surgery patients often have a co-existing presence of ………
ischemic cardiac disease
Useful meds for Thoracic Surgery patients with ischemic cardiac disease:
Cardioselective Beta-Blockers
(non-selective risk inhibiting bronchodilation)
Dyspnea in the supine position may be related to:
COPD
Compression of the airways –> mediastinal mass
diaphragm displacement d/t Obesity (FAT)
Lambert-Eaton syndrome = may be sensitive to………
Nondepolarizing muscle relaxants.
Patients will need LESS NDMBs!!!
________ tumors make up 20% of lung cancers
Neuroendocrine tumors
Occurs in 10-25% of patients with lung cancer related to parathyroid-like hormone, increased calcitriol, or overactivity of osteoclasts
Hypercalcemia
Cancer drugs (toxicities)
Bleomycin =
Doxorubicin=
Cisplatin =
Bleomycin = pulmonary toxicity
Doxorubicin = cardiac toxicity
Cisplatin = renal toxicity
What test can be a good initial assessment for pulmonary HTN?
ECHO
look it up before case
PaCO2 _____ mmHg is an indicator of poor ventilatory function
> 45 mmHg
This lab finding will Increase risk for postop pulmonary complications by as much as 2.5 times
Hypoalbuminemia
Most common lab finding in lung CA / Thoracic patients?
< ____g/dL
Hypoalbuminemia
< 3.6 g/dL
A ____% increase in FEV1 post bronchodilator treatment is considered significant
12%
Airflow assessment =
postop predictor of FEV1
PPO FEV1 <____% have a higher degree of likelihood to require postop ventilation
30%
Parenchymal function measure by:
DLCO
The extent of pulmonary surgery correlates _______with intraop partial pressure of arterial oxygen (PaO2)
inversely
How will PaO2 compare with pneumonectomy, lobectomy, and segmectomy?
PaO2 will be HIGHEST with pneumonectomy!!!
Intraoperative PaO2 pneumonectomy > lobectomy > segmectomy
(removes highest amount of diseased tissue which increases PaO2)
Removal of diseased lung tissue may not decrease pulmonary function it may…….
Improve it!!!
DLCO ____% of predicted value: associated with increased complications following pulmonary surgery
< 40%
Patient monitoring: obtain a baseline ABG within____ _____of initiating one lung ventilation
15 minutes
Is CVP reliable indicator of fluid in an open chest or lateral positioned patient?
NO!
90% of PA catheters float into the ____ _____ –> values will be falsely low
Right lung
Most common position during Thoracotomy:
Lateral Decubitus Position
Axillary roll should be placed just _____ to the axilla
caudal
Zone 1 =
PA > Pa > Pv
Zone 2 =
Pa > PA > Pv
Zone 3 =
Pa > Pv > PA
Perfusion is greatest in the _____ ______.
Dependent lung
Lateral Position: Anesthetized, Chest Closed, Spontaneous Ventilation:
____ decreases almost immediately upon initiation of anesthesia.
Reduced proportion in zone ___.
Ventilation is preferentially distributed to the _____ _______.
Gravity causes blood flow to preferentially go to dependent lung. Results in a……
FRC
3
nondependent lung
V/Q mismatch
Lateral Position: Anesthetized, Chest Closed Paralyzed, Mechanically Ventilated:
Under mechanical ventilation, the _______ no longer contributes to ventilation of the lower lung
____ ______ intensifies.
Addition of______ helps to restore some ____ and improve V/Q ratio
diaphragm
V/Q mismatch
PEEP
FRC
What position and situation would spontaneous ventilation be utterly useless?
Lateral Position: Anesthetized, Open Chest
Lateral Position: Anesthetized, Open Chest:
An immediate decrease in resistance to gas flow in the _______ ______.
nondependent lung
Lateral Position: Anesthetized, Open Chest, One-Lung Ventilation:
Ventilation to the _______ lung is ceased —-> ventilation is directed to the______ lung.
PaO2 is _____ during one lung ventilation in the lateral position than it is in the supine position
nondependent
dependent
higher
Lateral Position: Anesthetized, Open Chest, One-Lung Ventilation:
The remaining perfusion to the nondependent lung creates a shunt, but _____ reduces the shunt by ____ by diverting much of that blood towards the dependent lung
_______the airway to the nondependent lung reverses some of the changes that caused V/Q mismatch
HPV
50%
Clamping
Absolute Indications for One Lung Ventilation: long list
Isolation to avoid contamination: infection
Isolation to avoid spillage: massive hemorrhage
Control of the distribution of ventilation:
Bronchopleural fistula
Surgical opening at a major conducting airway
Giant unilateral cyst or bulla
Tracheobronchial tree disruption
Life-threatening hypoxemia related to unilateral lung disease
Need for unilateral bronchopulmonary lavage: pulmonary alveolar proteinosis
Relative Indications for One Lung Ventilation:
High priority only (only ones she focuses on)
Thoracic aortic aneurysm
Pneumonectomy
Thoracoscopy
Upper lobectomy
Mediastinal exposure
Gold standard of lung separation for ventilation
Double lumen endobronchial tubes
Most commonly used DLT?
Left DLT!
Does the bronchial lumen need to be placed within the bronchus of the operative lung?
NO
Can a DLT be used on small children?
NO
Internal diameters typically range from____ to ____.
37F has an external diameter equivalent to that of a standard _____ internal diameter ETT.
3.4 mm-6.6 mm
11mm
Double Lumen Endotracheal Tubes: Sizing
___for women up to 160 cm
___ for women over 160 cm
____ for men less than 175 cm
_____ for men over 175 cm
35F for women up to 160 cm
37F for women over 160 cm
37/39F for men less than 175 cm
39/41 for men over 175 cm
Slight movements of a _______________ can lead to malpositioning
right sided DLT
Double Lumen Endotracheal Tubes: Sizing
Most commonly seen: females ____, males ____
females 37F
males 39F
Most common complication of DLTs
Malpositioning
Rupture of a thoracic aneurysm with a ___________.
left sided DLT
Insertion of Double Lumen Endotracheal Tubes:
Rotate the ETT ____ degrees toward the bronchus that is to be intubated- advance ETT
Approximate depth of ____ cm in females and ____ cm depth in males –> stop if resistance is met
90 degrees
27 cm in females
29 cm in males
The tracheal cuff requires ____ mL of air
The bronchial cuff requires ____ mL of air
5-10
1-2
Bronchial cuff should be _______during the time that OLV is no longer needed to decrease risk of mucosal damage
Deflated
Advantages of Bronchial Blockers:
-Less complicated insertion- better for patients with a difficult airway or tracheostomy
-Better for patients who are already intubated
-Can be used in a pediatric population
What is HPV?
Why is it unique?
Compensatory mechanism to minimize shunt by increasing vascular resistance in hypoxic areas of the lungs
(A unique reflex since hypoxia usually causes vasodilation; arterial hypoxia has the opposite effect on pulmonary arteries)
HPV during OLV decreases the cardiac output to the nonventilated lung by approximately ___%
HPV can increase PVR by ___-___% in a state of chronic hypoxia
50%
50-300%
Will HPV work if more than 80% of the lung is hypoxic?
Nope
What will vasodilators do during HPV?
Inhibit it
Factors that Reduce Effectiveness of Hypoxia Pulmonary Vasoconstriction (long list)
Alkalosis
Excessive tidal volume or PEEP
Hemodilution
Hypervolemia (L atrial pressure >25 mmHg)
Hypocapnia
Hypothermia
Prostacyclin
Vasodilators, phosphodiesterase inhibitors, calcium channel blockers
Volatile anesthetics >1.5 MAC
Most common type of anesthetic used for OLV?
Volatile anesthetics
Gold Standard anesthetic for an Open Thoracotomy?
Epidural anesthesia: found to reduce complications without inhibiting HPV
Epidural catheter at the level of T6-T8
Why is hypoxemia more frequent in right sided lung surgery?
Due to anatomically larger/proportionally more perfusion to the right lung
OLV is best tolerated in the _____ position vs. _____.
lateral vs. supine
Causes of Hypoxemia During One Lung Ventilation: most common?
Tube malposition MOST COMMON: should be the first intervention
Bronchospasm
Decreased cardiac output
Hypoventilation
Low FiO2
Pneumothorax of dependent lung
1st intervention to manage Hypoxemia During OLV?
CPAP to the nondependent, nonventilated lung
Interventions to Manage Hypoxemia During OLV:
Alternative to CPAP: –>
What if interventions fail? –>
place a small catheter to deliver low-flow oxygen insufflation to the nondependent lung
If interventions fail, communicate with your surgeon to return to two-lung ventilation
Mediastinal Mass Biopsy should be done under _____ anesthesia whenever possible
local
Mediastinal Mass Biopsy: Gold standard if intubation is required?
Awake intubation with a flexible bronchoscope is the gold standard
-Maintain spontaneous ventilation if possible
IV placement for Mediastinal Mass Biopsy:
Place IV in a lower extremity —> sites above the SVC could delay drug’s effects due to slow distribution
Mediastinoscopy: biggest point?
Potential for LOTS of complications d/t location of important anatomical structures.
(left common carotid artery, the left subclavian artery, the innominate artery, the vagus nerve, left recurrent laryngeal nerve, the thoracic duct, the SVC, and the aortic arch)
Mediastinoscopy: Complications (long list)
Hemorrhage
Pneumothorax
Dysrhythmias
Bronchospasm
Left recurrent laryngeal nerve palsy
Laceration of the trachea or esophagus
Chylothorax from laceration of thoracic duct
Air embolism
Mediastinoscopy: Anesthesia Management
Watch for ________ with manipulation of the aorta/trachea during dissection —> have______ or ______available
bradycardia
glycopyrrolate or atropine
Preferred surgical approach for lobectomy in stage I non-small cell lung cancer ?
VATS
Preferred anesthetic method for Bullectomy:
Spontaneous ventilation under GA is preferred until the chest is open to decrease the risk of bulla rupture
Most common postoperative complications after Thoracotomy:
respiratory failure, cardiac dysrhythmias or failure, acute lung injury (ALI)
High risk patients that may require ICU postop: (after thoracotomy)
pulmonary fibrosis
age greater than 80
PPO FEV1 or DLCO less than 40%
ASA 4
surgical time longer than 80 minutes
Thoracotomy: Chest tube drainage >____ mL/hour necessitates surgical reexploration
200
Reduction in ____ ____ is greater following a pneumonectomy vs lobectomy
cardiac EF
Nerve Injuries following Thoracotomy
Damage to the phrenic nerve as it passes through the mediastinum
Damage to left recurrent laryngeal nerve
May happen during dissection of aortopulmonary lymph nodes and mediastinal procedures
Spinal cord injury can occur if an intercostal artery supplying a major radicular artery is damaged
