Compare cold blood cardioplegia with crystalloid cardioplegia.

• A. Cold blood cardioplegia uses patient’s blood with additives and provides oxygen-carrying capacity
• B. Crystalloid cardioplegia uses patient’s blood with additives
• C. Cold blood cardioplegia uses crystalloid solution and may require larger volumes
• D. Crystalloid cardioplegia provides oxygen-carrying capacity

Answer: (A)

The key idea is that these two cardioplegia options differ in what they bring to the heart during arrest, especially in oxygen delivery. Cold blood cardioplegia uses the patient’s own blood mixed with additives and cooled. Because it contains red blood cells, it still carries oxygen, helping to supply the myocardium during ischemia and supporting better protection of heart tissue. Crystalloid cardioplegia, on the other hand, is a salt-based solution without hemoglobin, so it does not provide oxygen-carrying capacity. Protecting the heart with crystalloid relies more on metabolic suppression, but it typically requires larger volumes to achieve the same effect, which can lead to hemodilution and electrolyte changes. So the statement that matches these differences is that cold blood cardioplegia uses the patient’s blood with additives and provides oxygen-carrying capacity.