Tetra of Fallot?

Bobmo88 · Jan 25, 2013

My patient this week was a peds patient with pneumonia. He had a history of open heart surgery to correct a congenital defect called Tetra of Fallot.
I looked up the defect in my med-surg book and on a couple Internet resources, but I don't really understand what it is and why it has an impact on a patient with a respiratory disease years after correction. I (vaguely) get that the defect causes oxygenation problems, so anything that impairs gas exchange would be a problem, but even after surgery?
Anyone care to help me out?

Hello! Tetralogy of Fallot is considered a cyanotic congenital heart disease. The cyanosis is usually due to a ventral septal that causes right to left shunting. The deoxygenated blood from the right side of the heart flows into the left side of the heart and is pumped into the systemic circulation. I did a little bit of research about this disease but couldn't seem to find a rationale for why they would be at an increased risk for pneumonia. I found that those that develop valve problems later on in life after surgery are at risk for developing endocarditis and right ventricle overload due to pulmonary valve incompetence. Was there anything else in the patient history that would cause an increased risk for pneumonia? Sorry I'm probably not too much help.

Stephalump · Jan 25, 2013

Thank you! You were actually a lot of help. The piece I was missing was the mixing of the blood in the heart, which explains the cyanosis.

I don't think he's at higher risk for pneumonia, but the defect made the pneumonia more urgent. His murmur was really pronounced (supposedly moreso than usually, according to his pediatrician) and his chest x-ray showed his heart was enlarged.

Anyway, I'm probably thinking way more in-depth than I need to (as usual.)

Thanks again!

allnurses Guide · Jan 25, 2013

Excellent learning experience on a classic but rate condition.

Think about the physiology of the four parts (or tetraology): pulmonary stenosis, overriding aorta, ventricular septal defect, and right ventricular hypertrophy. They will help you understand the pathophysiology as well as the normal anatomy of the fetal an newborn circulation.

Bobmo88 · Jan 25, 2013

Thank you! You were actually a lot of help. The piece I was missing was the mixing of the blood in the heart, which explains the cyanosis.
I don't think he's at higher risk for pneumonia, but the defect made the pneumonia more urgent. His murmur was really pronounced (supposedly moreso than usually, according to his pediatrician) and his chest x-ray showed his heart was enlarged.
Anyway, I'm probably thinking way more in-depth than I need to (as usual.)
Thanks again!

Glad I can help! If you ever have time, I would recommend watching the HBO movie called Something The Lord Made. It stars Alan Rickman and Mos Def and it's about how an African American named Vivien Thomas (Mos Def) who never went to college due to losing his savings when the banks failed in 1929, helps renowned surgeon Alfred Blalock (Rickman) research and perform the first cardiac surgery in the modern era. The condition they treated was Tetralogy of Fallot :)

Stephalump · Jan 25, 2013

Excellent learning experience on a classic but rate condition.
Think about the physiology of the four parts (or tetraology): pulmonary stenosis, overriding aorta, ventricular septal defect, and right ventricular hypertrophy. They will help you understand the pathophysiology as well as the normal anatomy of the fetal an newborn circulation.

Ok, so the pulmonary stenosis means there's less deoxygenated blood returning to the lungs to be reoxygenated.

The extra work causes the right ventricular hypertrophy.

The VSD means there's a hole between the right and left ventricles, so deoxygenated blood from the right side is mixing with blood on the left.

And the overriding aorta is located too far to the right and over the defect, so it's getting a mix of oxygenated and deoxygenated blood and pumping it to the body.

Hopefully that's right...I've only had one semester of med-surg so far, so I'm attempting to teach this to myself.

So I can see why pneumonia would be an added concern, but from what I can tell the surgeon should have repaired the VSD and widened the valve during the open heart surgery years ago. Maybe I'm overestimating the results of treatment, but I don't understand why the defect is still a factor in the pneumonia.

Stephalump · Jan 25, 2013

Glad I can help! If you ever have time, I would recommend watching the HBO movie called Something The Lord Made. It stars Alan Rickman and Mos Def and it's about how an African American named Vivien Thomas (Mos Def) who never went to college due to losing his savings when the banks failed in 1929, helps renowned surgeon Alfred Blalock (Rickman) research and perform the first cardiac surgery in the modern era. The condition they treated was Tetralogy of Fallot :)

On, very cool! I'll put it on my "to watch" list! :)

Esme12, ASN, BSN, RN · Jan 25, 2013

http://www.mayoclinic.com/health/tetralogy-of-fallot/DS00615

Tetralogy of Fallot is a combination of four congenital abnormalities. The four defects are a ventricular septal defect (VSD), pulmonary stenosis, a misplaced aorta and a thickened right ventricular wall (right ventricular hypertrophy). They usually result in an insufficient amount of oxygenated blood reaching the body.

Any time someone with heart/valve deficits/disease any infection is of the utmost concern for they remain vulnerable to endocarditis. These children are usually frail and are susceptible to infection.

Herre is an excellent resource for Tetralogy from medscape....it requires registration but it is free.....Medscape: Medscape Access

Esme12, ASN, BSN, RN · Jan 25, 2013

Ok, so the pulmonary stenosis means there's less deoxygenated blood returning to the lungs to be reoxygenated.
The extra work causes the right ventricular hypertrophy.
The VSD means there's a hole between the right and left ventricles, so deoxygenated blood from the right side is mixing with blood on the left.
And the overriding aorta is located too far to the right and over the defect, so it's getting a mix of oxygenated and deoxygenated blood and pumping it to the body.
Hopefully that's right...I've only had one semester of med-surg so far, so I'm attempting to teach this to myself.
So I can see why pneumonia would be an added concern, but from what I can tell the surgeon should have repaired the VSD and widened the valve during the open heart surgery years ago. Maybe I'm overestimating the results of treatment, but I don't understand why the defect is still a factor in the pneumonia.

The heart and lungs are very interdependent on each other.

LadyFree28, BSN, LPN, RN · Jan 25, 2013

Ok, so the pulmonary stenosis means there's less deoxygenated blood returning to the lungs to be reoxygenated.
The extra work causes the right ventricular hypertrophy.
The VSD means there's a hole between the right and left ventricles, so deoxygenated blood from the right side is mixing with blood on the left.
And the overriding aorta is located too far to the right and over the defect, so it's getting a mix of oxygenated and deoxygenated blood and pumping it to the body.
Hopefully that's right...I've only had one semester of med-surg so far, so I'm attempting to teach this to myself.
So I can see why pneumonia would be an added concern, but from what I can tell the surgeon should have repaired the VSD and widened the valve during the open heart surgery years ago. Maybe I'm overestimating the results of treatment, but I don't understand why the defect is still a factor in the pneumonia.

The defect is still a factor for pneumonia due to the prolonged time that the pt had proper circulation...when the oxygen exchange during the circulatory process is compromised, the higher risk of respiratory acidosis..it's a homeostasis/ acid-base balance thing.

As for the surgeon repairing the VSD...there are factors when repairing the heart and cardiac surgery in pediatrics...children's bodies function differently than adults. There may be growth compromise as well. As a nurse who has cared for cardiac kids for the bulk of my almost 8 years being a nurse, there are metabolic issues when there is a compromise in the cardiac cycle...when these children go through the process of cardiac repair and cardiac rehabilitation, there is a goal for these kids dependent on the surgeon...some surgeons want them to be at a certain weight to see if the repair can prevent potential complications of new "stress" on the heart...think about it...the heart has been diverting ALLL over the place, now it is going into places that had little perfusion, there is a chance for fluid overload, causing potential organ failure...it's like placing a sponge into a full bucket of water, totally over soaking and saturating the sponge causing it to leak over...now what if the sponge is a lung??? Hope this helps! (Hope I didn't confuse you! :) )

allnurses Guide · Jan 25, 2013

My patient this week was a peds patient with pneumonia. He had a history of open heart surgery to correct a congenital defect called Tetra of Fallot.
I looked up the defect in my med-surg book and on a couple Internet resources, but I don't really understand what it is and why it has an impact on a patient with a respiratory disease years after correction. I (vaguely) get that the defect causes oxygenation problems, so anything that impairs gas exchange would be a problem, but even after surgery?
Anyone care to help me out?

As far as his PNA, tell us your assessment? How was his breathing? Did he have a history of needed supplemental oxygen support? Was he vibrant or frail? How long ago was the surgery? Did he have a murmur? How did his lungs sound?

Was his pna lobar or interstitial?

Esme12, ASN, BSN, RN · Jan 26, 2013

the defect made the pneumonia more urgent. His murmur was really pronounced (supposedly moreso than usually, according to his pediatrician) and his chest x-ray showed his heart was enlarged.

This child has an enlarged heart and a murmur placing him at greater risk for comlications.....and more vulneralbe to infections