Clinicology

Myeloperoxidase is the last enzyme in the generation of reactive oxygen species (ROS), specifically hypochlorite, in neutrophils. It contains a heme-containing pigment, which gives sputum its yellow-green color.

superior vena cava (SVC) syndrome occurs when a tumor compresses the superior vena cava, thereby obstructing venous return to the right atrium. consequently, retrograde blood pooling in the head, neck, and arms produces facial plethora and upper extremity edema.
the superior vena cava is derived from the common cardinal veins.