Similarly, blood group B has only B antigens, blood group AB has both, and blood group O has neither A nor B antigens on the surface of the red blood cells. These four groups are the most important because they indicate which blood type a patient can safely receive in a transfusion.
Hemoptysis (which is pronounced he-MOP-tis-is) is coughing up blood from the respiratory tract. Blood can come from the nose, mouth, throat, the airway passages leading to the lungs, or the lungs. The word hemoptysis comes from the Greek haima, meaning blood, and ptysis, which means a spitting. Blood-tinged mucus in a healthy nonsmoker usually indicates a mild infection.
Hemoptysis is coughing up of blood from the respiratory tract. Massive hemoptysis is production of â¥ 600 mL of blood (about a full kidney basinâs worth) within 24 h. Most of the lungâs blood (95%) circulates through low-pressure pulmonary arteries and ends up in the pulmonary capillary bed, where gas is exchanged.