i'm confused between the two hemoglobin affinity options. why would tissue hypoxia not cause peripheral cyanosis
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21 Mar 2024
hb affinity
Question:
A 59-year-old man presents to your clinic for a regular checkup. During the physical examination, you notice he has a bluish discoloration on his lips and fingertips. He mentions that he has been feeling a bit fatigued recently. Understanding the physiological changes in the body, which of the following would you consider to be the most probable cause of his condition?
Options:
A)Decreased erythropoiesis
B)Increased hemoglobin affinity for oxygen
C)Decreased hemoglobin affinity for oxygen
D)Reduced cardiac output
E)Pulmonary hypertension
hb affinity
Question:
A 59-year-old man presents to your clinic for a regular checkup. During the physical examination, you notice he has a bluish discoloration on his lips and fingertips. He mentions that he has been feeling a bit fatigued recently. Understanding the physiological changes in the body, which of the following would you consider to be the most probable cause of his condition?
Options:
A)Decreased erythropoiesis
B)Increased hemoglobin affinity for oxygen
C)Decreased hemoglobin affinity for oxygen
D)Reduced cardiac output
E)Pulmonary hypertension
You have to remember that oxygenated hemoglobin (oxyhemoglobin) causes a bright red appearance of blood. You’d expect this if affinity for O2 increases.
Deoxyhemoglobin causes dark red blood. There is bluish-purple discoloration of tissues due to hypoxia, and that’s what causes cyanosis. You’d expect this if affinity of O2 decreases (making that the correct answer).
Note: this is fairly high yield
You have to remember that oxygenated hemoglobin (oxyhemoglobin) causes a bright red appearance of blood. You’d expect this if affinity for O2 increases.
Deoxyhemoglobin causes dark red blood. There is bluish-purple discoloration of tissues due to hypoxia, and that’s what causes cyanosis. You’d expect this if affinity of O2 decreases (making that the correct answer).
Note: this is fairly high yield