Term
| T or F: ASD produces a right to left shunt. |
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Definition
| False. Think about it...after birth systemic BP is greater than pulmonary BP. LAP overcomes RAP and blood is shunted back to the lungs. |
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Term
| What kind of infections are frequent in kids with ASD? |
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Definition
| Pulmonary. They get too much blood flow back to the lungs-->increased water leakage out of pulmonary vasculature-->lung infections. |
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Term
| Kids with ASD have a murmur. Where is it heard? During what part of the cardiac cycle does it occur? |
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Definition
Over the pulmonary valve.
During systole (systolic murmur).
The second heart sound (closure of pulmonic and aortic valves) will have a "wide split"...whatever that means. |
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Term
| When must an ASD be surgically corrected? |
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Definition
| When pulmonic blood flow is 2x that of systolic blood flow. |
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Term
| What are the adverse outcomes of ASD? (Hint: what chamber is mostly affected, where does HTN occur?) |
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Definition
- increased RV work
- RV failure
- pulmonary HTN
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Term
| T or F: Because an ASD is a R to L shunt, you want to avoid drugs that increase PVR. |
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Definition
| False! ASD is a L to R shunt, therefore you want to avoid drugs or conditions that increase SVR |
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Term
| T or F: The overall goal for an ASD is to decrease SVR (volatiles and peripheral vasodilators are good) and maintain PVR (positive pressure ventilation is good). Doing this will decrease the shunt. |
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Definition
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Term
| What murmur is a "classic" sign of VSD? |
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Definition
| pansystolic murmur (heard along the left sternal border) |
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Term
| A large one of these will cause symptoms to appear within 4 weeks of age. These symptoms include CHF, pulmonary infections, tachypnea, and failure to thrive. |
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Definition
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Term
| With a large VSD massive amounts of blood can go back into the R ventricle and reenter the pulmonary vasculature. What is a surgical technique that may be used to reverse this phenomenon. |
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Definition
| pulmonary banding (temporary fix to reduce the flow through the pulmonary system until the VSD can be repaired) |
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Term
| Aside from worrying about the L to R shunt in your patient with a VSD, what other complication can occur, especially during/after the procedure to fix a VSD? |
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Definition
| Dysrrythmias -- especially high AV blocks or even 3rd degree blocks that can occur due to formation of scar tissue, which does not conduct action potential! |
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Term
| If your patient has Eisenmenger syndrome, their original shunt must've been pretty bad. Was their original shunt L to R or R to L? What did it progress to? |
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Definition
- start out with a really bad L to R shunt
- PVR rises tremendously from the overload-->so much so that the original L to R shunt becomes a R to L shunt. Now we're bypassing the lungs, getting cyanotic and creating a new set of problems.
Another way to put it: Eisenmenger syndrome creates a cyanotic shunt from an acyanotic shunt. |
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Term
| You know you're gonna have to do this on the exam: Name the 4 anatomic features of the Tetrology of Fallot. |
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Definition
- VSD
- Pulmonary outflow tract obstruction
- overriding aorta
- Right ventricular hypertrophy
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Term
T or F:
Qp/Qs>1 in an infant with TOF |
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Definition
| False, TOF is a R to L shunt (bypasses the lungs-->you're not getting as much blood to the lungs-->Qp/Qs<1) |
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Term
| T or F: A high SVR is a good thing for the TOF patient. |
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Definition
| True. It lessens the severity of the R to L shunt. It is a main determinent (the other is the degree of pulmonary outflow tract obstruction) in how much blood is shunted. When you decrease SVR, you increase the amount of blood that bypasses the lungs, thus increasing hypoxia and cyanosis-->got yourself a TET spell |
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Term
| You're trying to treat a severe TET spell in a TOF patient. What interventions can you employ? How does each one work? |
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Definition
- 100% FiO2 (decreases hypoxia-->decreases HPV-->decreases PVR)
- knee to chest position (increases SVR-->lessens amount of blood shunted-->more blood passes through the lungs and picks up oxygen)
- phenylephrine (same as above)
- morphine (decreases PVR, thus increasing amount of blood that goes to the lungs)
- crystalloids (Don't recall what the exact explanation was...I'm guessing it would decrease HR and maybe allow for more oxygenation)
- beta-blockers (I think Gayle said that this allows more time for oxygen exchange in the lungs but I'm not so sure)
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Term
| What are the two main things fixed (anatomically speaking) by surgical intervention on the TOF patient. |
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Definition
- removing the pulmonary valve (fixes pulmonary outflow tract obstruction)
- fixing the VSD (remember that this causes a lot of junctional arrythmias)
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Term
| What the hell is an overriding aorta anyway? How does it contribute to the pathology seen in the TOF patient? |
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Definition
The "overriding" part comes from the fact that the aorta sits right over the VSD.
This means that the right ventricle shoots its juice right into that overriding aorta. Additionally, the "overriding" aorta appears to push up against the mitral valve and keeps it from fully opening to let the LA blood drian into the LV. |
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