WS: Blood Gas Transport

400 ml is the correct answer. This one is tricky to calculate, often students will correctly calculate 200 times 0.04 to get the number 8 ml. However, this is 8 ml per 100 ml of plasma. Since the question is asking for total dissolved oxygen, the 8 ml per deciliter has to be multiplied by 50 deciliters of total blood volume, which yields the correct answer of 400 ml.

For one of our alien species, their PaO2 back on their home planet is normally 200 mmHg and their blood is somewhat different, with a solubility constant for O2 of 0.04 ml/100ml/mmHg. If their total blood volume is 5 liters, what is the total amount of dissolved oxygen in their blood on their home planet? 50 ml 400 ml 8 ml 80 ml

Haldane effect is the correct answer. The Haldane effect is the phenomenon that deoxyhemoglobin has a higher affinity for CO2, and the green curve is fully deoxygenated Hb. The red curve is fully oxygenated Hb, so since points D and E are aligned at the same PCO2, but point D is a higher total blood CO2, this is the direct graphical representation of the Haldane effect.

Question 10 1 / 1 pts The difference between points D and E illustrates the blood-gas-transport_q10.png Haldane effect bicarbonate shift dissolved CO2 Bohr effect

Molecular structure, temperature, and solvent is the correct answer. This one is rather straightforward.

Question 2 1 / 1 pts The solubility constant of a gas depends on molecular structure, temperature, and solvent molecular structure, temperature, solvent, and partial pressure molecular structure of that gas molecular structure and temperature

13 ml O2/dl is the correct answer. This one requires that we take the SaO2 of 65% times normal hematocrit (15g/dl) times normal hemoglobin oxygen binding affinity (1.34 ml O2/g).

Question 3 1 / 1 pts Assume an oxyhemoglobin saturation of 65% in normal conditions is life-threatening. What would be the hemoglobin-bound content at this life-threatening level? 13 ml O2/dl 16 ml O2/dl 10 ml O2/dl 30 ml O2/dl

Increased, increase in pH is the correct answer. A decreased P50 means a leftward shift in the hemoglobin dissociation curve, which is an increased affinity of hemoglobin for oxygen (i.e. P50 is reached at a lower PaO2). One of the causes for this would be an increase in pH.

Question 4 1 / 1 pts A decreased P50 in the hemoglobin dissociation curve means a(n) _ affinity of hemoglobin for oxygen and would occur with a(n) ____. decreased, increase in pH decreased, increase in temperature decreased, increase in PCO2 increased, increase in temperature increased, increase in PCO2 increased, increase in pH

Increase, increased is the correct answer. This is depicted on any standard set of hemoglobin dissociation curves, and is a consequence of increased BPG mutase activity with decreased pH.

Question 5 1 / 1 pts In respiratory acidosis (e.g. pH of 7.3), the concentration of 2,3 - BPG will _ resulting in a(n) __ P50 for the hemoglobin dissociation curve. decrease, increased increase, decreased increase, increased decrease, decreased

Decreased is the correct answer. Since the question is asking about hematocrit and describes a right-ward shift in the Hb dissociation curve, this would occur when hematocrit has decreased, e.g. anemia.

Question 6 1 / 1 pts If the P50 for hemoglobin shifted from a PO2 of 28 mmHg to 40 mmHg, with no changes in temp, pH, 2,3-BPG, or PCO2, this would mean that the hematocrit has not changed increased decreased

Needs ... hematocrit is low is the correct answer. While at first it looks like a calculation might be needed, this is not the case; the value of 11 g/dl is significantly below normal (e.g. anemia). It is critical to remember that in anemia the PaO2 and SaO2 can be normal, but the CaO2 is what actually matters for adequate oxygen delivery at the tissue level.

Question 7 1 / 1 pts For a patient with a hematocrit of 11 g/dl, a PaO2 of 95 mmHg, and an SaO2 of 98%, the clinician (needs/need not) be concerned because the ______. need not ... A-a gradient is high needs ... PaO2 and SaO2 are normal need not ... PaO2 and SaO2 are normal needs ... hematocrit is low need not ... hematocrit is low needs ... A-a gradient is high

36 ml O2/dl is the correct answer. Two values have to be determined for CaO2 - dissolved and hemoglobin bound. For dissolved, we use PaO2 X solubility constant = 4 ml O2/dl. For Hb bound, it's 20 g/dl X 2 ml O2/g X 0.8 = 32 ml O2/dl.

Question 8 1 / 1 pts For the same alien species in question 1 above, their unique hemoglobin has 6 binding sites such that 1 g holds 2 ml O2. Their hematocrit is 20 g/dl. While visiting us their PaO2 is 100 mmHg and SaO2 is 80%, so what is their total oxygen content (CaO2)? 32 ml 02/dl 20 ml 02/dl 40 ml 02/dl 36 ml 02/dl

D is the correct answer. From top to bottom the curves are normal, carbon monoxide poisoning, and 50% anemia. On the anemia curve, since venous blood would have a PaO2 of 40, this is point D.

Question 9 1 / 1 pts Which point in the figure below represents % oxyhemoglobin in the venous blood of a patient with 50% anemia? blood-gas-transport_q9.png C D E A B