Question

In the movie 'Something the Lord Made', Dr. Alfred Blalock (played by Alan Rickman, aka Severus Snape of the Harry Potter movies) devised a surgical procedure to correct a serious heart defect in children with Blue baby syndrome. Dr. Blalock initiated the medical practice of heart surgeries in an era when no one believed it was possible to do surgery on the heart and have the pateint survive. The surgery was extremely experimental at the time, only the most severe diseases would even be contemplated for such a procedure. The problem was children were born with a severe genetic deformity of the heart that inevitiably led to death. These children have a very narrow pulmonary artery leaving the right ventricle. A defect with the pulmonary valve reduces blood flow at this point. In addition there is a hole in the ventricular septum and blood from the ventricles can pass back and forth between the left and the right ventricles. Knowing what you do about how the blood flows through the heart, explain what effect this deformity would have on the normal functioning of the heart. Think about the effects of mixing oxygenated and deoxygenated blood. Why do they call this blue baby syndrome? There are several causes of BBS, do not give explanations for the others, focus on the condition described here.

Answer 1

The children born with very narrow pulmonary artery will develop blue baby syndrome. This is because the amount of deoxygenated blood from the right ventricle which goes to the lungs for oxygenation is reduced. Further, the defect in interventricular septum between the two ventricles leads to mixing of oxygenated and deoxygenated blood which gets pumped to rest of the body by aorta from left ventricle. The decreased oxygen content of blood leads to cyanosis causing blue baby syndrome.