Chapter 6 - Cardiothoracic Surgery Flashcards
When a child has expiratory wheezing, it suggests ___.
Bronchoconstriction, i.e., asthma
When a child has inspiratory wheezing, it suggests ___. If the child also has difficult swallowing, as well as episodes of respiratory distress, with crowing respiration, stridor, and hyperextension of the neck, what is the problem?
Tracheomalacia, where the tracheal rings collapse
Vascular ring, a congenital anomaly in which the trachea and esophagus are encircled by abnormal blood vessels
Dx and Rx vascular ring?
Extrinsic compression demonstrated by barium swallow and bronchoscopy
Surgery divides the smaller of the two aortic arches
Dx morphologic cardiac anomalies (congenital or acquired)?
Echo
Presentation of L to R shunts in general?
Murmur
Overloading of pulmonary circulation with long-term damage to the pulmonary vasculature
(Volume and consequences of shunt vary based on location)
List the 3 major L to R shunts.
ASD
VSD
PDA
Presentation of ASD?
Very minor, low-pressure, low-volume shunt
Typically recognized in late infancy
Pulmonary flow systolic murmur and fixed split second heart sound
History of frequent colds
Rx ASD?
Closure can be achieved surgically or by cardiac catheterization
Presentation of a small, restrictive VSD low in the muscular septum?
Murmur, but otherwise few symptoms
Rx small restrictive VSD low in the muscular septum?
None - likely to close spontaneously within the first 2-3 years
Presentation of VSD (typical location high in the membranous symptom)
Failure to thrive in the first few months
Loud pansystolic murmur best heard at the left sternal border
Increased pulmonary vascular markings on CXR
Rx VSD?
Surgical closure
Presentation of PDA?
Symptomatic in the first few days of life
Bounding peripheral pulses
Continuous machinery-like heart murmur
Rx PDA?
Premature infants who have not gone into CHF - indomethacin
Premature infants who fail indomethacin, those already in failure, and full-term babies -> surgical division or radiological embolization with metal coils
Shared features of a R to L shunt?
Murmur
Diminished vascular markings in the lung
Cyanosis
List the 2 most common R to L shunts.
- Tetralogy of Fallot (most common)
2. Transposition of the great vessels
Presentation of Tetralogy of Fallot?
Allows children to grow up into infancy
Small for their age
Bluish hue in the lips and tips of fingers
Clubbing
Spells of cyanosis relieved by squatting
Systolic ejection murmur in the L 3rd intercostal space
Small heart
Diminished pulmonary vascular markings on CXR
EKG signs of RVH
Rx Tetralogy of Fallot?
Surgical repair
Presentation of transposition of great vessels?
Kept alive by ASD, VSD, PDA, or a combination, die if not corrected
1 or 2-day-old child with cyanosis who is in deep trouble
Presentation of aortic stenosis?
Angina and exertional syncopal episodes
Harsh mid-systolic heart murmur heard best at the R second intercostal space and along the L sternal border
Work-up for suspected aortic stenosis?
Start with echo
When is surgical valvular replacement indicated in aortic stenosis?
If there is a gradient of more than 50 mm Hg
At the first indication of CHF, angina, or syncope
Presentation of chronic aortic insufficiency?
Wide pulse pressure
Blowing high-pitched, diastolic heart murmur best heard at the second intercostal space and long the left lower sternal border with the patient in full expiration
Rx chronic aortic insufficiency?
Medical therapy for many years
Should undergo valvular replacement at the first evidence on echo of beginning left ventricular dilatation
Presentation in acute aortic insufficiency?
2/2 endocarditis - young drug addicts who suddenly develop CHF and a new loud diastolic murmur at the R second intercostal space
Rx acute aortic insufficiency (2/2 endocarditis)?
Emergency valve replacement
Long-term ABX
Who needs antibiotic prophylaxis for subacute bacterial endocarditis?
Patients with a prosthetic valve
Presentation of mitral stenosis?
Caused by rheumatic fever many years before presentation
Produces dyspnea on exertion, orthopnea, PND, cough, hemoptysis
Low-pitched, rumbling diastolic apical heart murmur
With progression, patient becomes thin and cachectic and develop AF
Work-up and Rx mitral stenosis?
Start with echo
As symptoms become more disabling, MV repair becomes necessary with a surgical commissurotomy or a balloon valvuloplasty
Presentation of mitral regurgitation?
Most commonly caused by valvular prolapse
Develop exertional dyspnea, orthopnea, and AF
Apical, high-pitched, holosystolic heart murmur that radiates to the axilla and back
Work-up and Rx mitral regurgitation?
Start with echo
As symptoms become disabling, symptoms become necessary with repair of valve (annuloplasty) preferred of prosthetic replacement
Typical patient with coronary disease?
Middle-aged sedentary man with a family history, history of smoking, DM2, and hypercholesterolemia
Main reason to do a cardiac catheterization?
Progressive, unstable, disabling angina, evaluate candidacy for revascularization
When is revascularization indicated?
If 1+ vessels have 70% or greater stenosis and there is a good distal vessel.
Rx options for coronary artery disease?
The general rule is the simpler the problem, the more it is amenable to angioplasty and stent whereas more complex situations do better with surgery.
Single vessel disease that is not the left main or the anterior descending is perfect for angioplasty and stent
Triple vessel disease makes multiple coronary bypass (using the internal mammary for the most important vessel) the best choice.
Post-op care of heart surgery patients often requires that cardiac output be optimized. If CO is considerably under normal (___), what should be measured? Low numbers suggest what? High numbers?
5 L/min or a cardiac index of 3
Pulmonary wedge pressure or left atrial pressure or left end-diastolic pressure
Low numbers (0-3) - more IV fluids High numbers (20+) - ventricular failure
A coin lesion found on CXR has what % chance of being malignant in people over the age of 50 and even higher if there is a history of smoking?
80
Work-up of coin lesion?
First step is always to seek an older CXR, as a 1-2 year old CXR showing the same unchanged lesion is not cancer.
If not available, or the lesion was not present in a previous film, some do a biopsy right away. However, it is prudent to do non-invasive studies before invasive ones, and thus I suggest that the next step should be sputum cytology and CT scan of the chest and upper abdomen to look for mets.
If not established by cytology, how is cancer of the lung diagnosed?
Bronchoscopy and biopsy for central lesions or percutaneous biopsy for peripheral lesions
If unsuccessful -> video-assisted thoracic surgery (VATS) and wedge resection may be needed.
What determines how far you progress through the work-up for possible lung cancer (beyond sputum cytology and CT scan)?
Probability of cancer (higher in elderly with history of smoking and non-calcified lesion in CT)
Assurance that surgery can be done (residual pulmonary function will suffice)
Chances that the surgery may be curative (no mets to mediastinal or carinal nodes, the other lung, or the liver)
Rx small cell cancer of the lung?
Chemo and radiation
NOT SURGERY - operability and possibility of surgical cure applies only to non-small cell cancer
What determines operability of lung cancer?
Residual function after resection (assuming pneumonectomy is required; for lobectomy, function is less of an issue)
What types of lesions require pneumonectomy vs. lobectomy?
Central lesions - pneumonectomy
Peripheral lesions - lobectomy
For pneumonectomy, what is the minimum FEV1 needed?
800 mL
How should the decision be made regarding operability of lung cancer?
Minimum FEV1 800 mL needed
If clinical findings (COPD, SOB) suggest this may be the limiting factor, PFTs are done. Determine FEV1, determine fraction that comes from each lung (VQ scan), figure out what would remain after pneumonectomy.
If less than 800 mL, stop - not a surgical candidate. Treat w/chemo and radiation
Potential cure by surgical removal of lung cancer depends on the extent of ___. Discuss.
Mets; hilar mets can be removed with the pneumonectomy, but nodal mets at the carina or mediastinum preclude curative resection.
CT may identify nodal mets. Addition of PET scanning has helped define the presence of an actively growing tumor in enlarged nodes.
Endobronchial U/S is more invasive option to sample mediastinal nodes.
Mets to other lung, adnrela, or liver should be evidence on CT
Immunotherapy options for Rx of non-small cell lung cancer?
Pembrolizumab and nivolumab
