Pulmonary resection Flashcards
What is the three legged stool method for preop assessment for pulmonary resection?
Respiratory mechanics, lung parenchymal function, and cardiopulmonary interaction (exercise testing)
What is the single most valid test for postthoracotomy respiratory complications:
How is that calculated?
Is the predicted postoperative FEV% (ppoFEV1%)
Calculated as: preop FEV1% (predicted FEV1%) x (1-the %functional lung tissue removed/100)
How do you estimate the amount of tissue removed?
RUL: 6 segments
RML: 4 segments
RLL: 12 segments
LUL and LLL are 10 segments each
Which ppoFEV is associated with respiratory complications and need for mechanical ventilation postoperatively?
<30-40% (this is under respiratory mechanics)
Lung parenchymal fxn (ppoDLCO)-what value is associated with increased risk of both cardiac and respiratory complications. What is it independent of ?
ppoDLCO <40% predicted is associated wiht an increased risk of both cardiac and respiratory complications (and is independent of the FEV1)
What is the DLCO?
What increases it? What decreases it? Briefly explain DLCO and area and thickness.
It is a measurement of the diffusion of the lungs.
DLCO-diffusion is worsened by decreased area (emphysema), increased thickness (fibrosis). Decreased also by:cigarette smoking, emphysema, interstitial lung disease, anemia, decreased lung volume, heart failure, pulmonary vascular disease (pulmonary emboli and pulmonary hypertension)
Increased by:
asthma, obesity, high altitude, lying supine, exercise, left-to-right cardiac shunt, polycythemia, pulmonary hemorrhage
What about the cardiopulmonary interaction (exercise testing) ?
VO2 max can correlate with risk of morbidity and mortality-can be impractical
stair climbing: <2 flights is high risk
6 minute walk test: patients walk as far as they can for 6 minutes. <2,000 feet correlates with an increase in morbidity and mortality
Lets talk extubation: what if ppoFEV1 is:
>40%
Between 30-40%
Between 20-30%
> 40%: possible to extubate provided that the patient is awake, comfortable, and warm
30-40%: extubation should be possible provided minimal co-existing disease (CAD, dysrhythmias, COPD)
20-30%: if parenchymal fxn/testing and exercise testing is favorable-extuabtion can be considered if thoracic epidural or paravertebral analgesia is used. Otherwise-they need to go to ICU for staged weaning.
Who would have to get a pulmonary resection?
lung cancer, mass effect, airway narrowing, postobstructive pneumonia, mets, chemo, Eaton lambert syndrome, hypercalcemia
What is Eaton Lambert syndrome?
When the body makes antibodies against the presynaptic calcium channels at the NMJ-decreased ACh secretion
What are complications related to removal of bronchopulmonary segments and vasculature?
pul HTN, and right heart failure, dysrhythmias, pulmonary edema
Issues with being in the lateral position in pulmoary resection:
potential nerve/eye/brachial plexus injuries
Anticipating what intraop and post op?
Intraop: anticipation of arterial hypoxemia with OLV, mod-severe pain that intrfers with recovery
What would you want to get from a history and physical?
History: coexisting diseases-smoking, COPD, dyspnea, orthopnea, exercise tolerance. Chemo-affectedwith bleomycin
Physical exam: RR, wheezing, rales, cyanosis, clubbing SVC syndrome, room air SpO2
What is SVC syndrome
Obstruction of blood returning to SVC-Swelling of the face, neck, upper body, and arms.
Trouble breathing or shortness of breath.
Coughing
What lab tests/imaging would you want to get?
CBC, electrolytes, Calcium, ABG if COPD
Review CXR and CT scan (difficult placement of DLT due to tracheobonchial distortion?
PFTs, V/Q scan if ppoFEV1 <40% ?
Conflicts that can occur in this case:
Difficult airway versus need for large DLT
Hypoxemia and need to inflate operative lung versus interference with surgical exposure
How can you optimize these patients?
I can perform a risk assessment (ppoFEV1, ppoDLCO, exercise testing)
Incentive spirometry prior to Sx
Smoking cessation
prescribe/continue bronchodilator (albuterol B2 agonist, anticholinergics (ipratropium)
Goals of surgery:
maintain lung separation and oxygenation, prevent post-op pulm comlciations
Options for anesthesia:
GA + thoracic epidural or paravertebral block (not as confident with this one)
Pre-op-pre med, blood, ICU?
pre-oop antisialogogue for FOB
2 units PRBC
ICU/Stepdown bed-yes
Room set up:
Arterial line, difficult airway cart with FOB
What kind of tube are you using?
DLT (37-39 Fr for males, 35-37 Fr for females)
How are you going to maintain anesthesia?
balanced anesthetic with volatile gas and IV narcotics,
May require CPAP on operative lung +/- PEEP to nonoperative lung for hypoxiemia
Adjust TV to keep PIP <35 cm H20
Disposition/Pain: what helps with decreasing post op respiratory complications? What about NSAIDs?
Regional anesthesia can decrease postop respiratory complications, and no NSAIDs if on cis-platin (causesrenal toxicity)
