GMS6402 PRACTICE EXAM TEST 2025/2026 QUESTIONS
AND SOLUTIONS GRADED A+ TIP
✔✔CO Poisioning - ✔✔- left shift
- O2 displaced from Hb
- PaO2 remains normal
- P50 decreased
✔✔Polycythemia O2 content - ✔✔- 26.57 mls O ml blood
✔✔Anemia O2 content - ✔✔- 13.44 mls O ml blood
✔✔Venous O2 content - ✔✔- 15 mls O ml blood
- tissue consumes appr. 5 mls
- 75% Hb sat.
✔✔O2 delivery to tissure - ✔✔- 250 mls O2 / min
- CO x (art. O2 - ven. O2)
- O2 demand per min ~ 250 mls O2
✔✔Pulse oximetry - ✔✔- measures R/IR ratio
- 0.5 = 100% sat.
- 1.0 = 82% sat.
✔✔RBCs in pulmonary capillaries - ✔✔- traverse 3 alveoli
- in pulm. capil. bed ~ 0.75 sec
- diffusion complete after ~0.25 sec or one alveoli
✔✔Pulmonary blood pressure - ✔✔- 14 mmHg - low pressure
- high flow
- high compliance
✔✔Pulmonary capillary recruitment - ✔✔- 75 ml at norm. to 200 + ml during exercise
- capillaries that were previously without perfusion are recruited
- distention dialtes blood vessels further allowing for increased blood volume
✔✔V/Q ratio - ✔✔- ventilation perfusion ratio
✔✔V/Q normal - ✔✔- 0.8
- 4.2 l/min AV / 5.5 l/min CO
✔✔V/Q shunt - ✔✔- 0
- perfused but no ventilation
, ✔✔V/Q PE - ✔✔- infinity
- ventilated but no perfusion
✔✔Causes of hypoxemia - ✔✔1) hypoventilation
2) altitude
3) diffusion limitation
4) shunt
5) V/Q mismatch
✔✔Low flow disorder - ✔✔- PE
- V/Q = infinity
✔✔High pressure disorder - ✔✔- Left sided heart failure
- Pulmonary hypertension
- Postprandial dyspnea
✔✔Left sided heart failure - ✔✔- decreased left ventricle EF causes blood to back up in
lungs
- increases hydrostatic pressure in lungs
- pushing fluid out into the alveoli
- pulmonary edema
✔✔Pulmonary hypertension - ✔✔- hypertension within pulmonary circulation
- causes pulmonary edema
- Phen/Fen prescribed in the 90s caused it
✔✔Postprandial dyspnea - ✔✔- increased blood volume in lungs due to laying supine
after large meal
- higher pulmonary pressure pushes fluid into alveoli
- stomach size redces ability of diaphragm to contract
- equals dyspnea
✔✔Pulmonary edema - ✔✔- increased path of diffusion
- surfactant lost
- obstructive disorfer
- causes shunting
✔✔Fluid movement in lungs - ✔✔- low perfusion pressure pushes small amounts of
fluid into interstitium
- mostly re-absorbed into capillary
- some drained by lymphatics
✔✔Early stage/interstitial edema - ✔✔- increases diffusion difference for O2 and CO2
between alveoli and plasma
AND SOLUTIONS GRADED A+ TIP
✔✔CO Poisioning - ✔✔- left shift
- O2 displaced from Hb
- PaO2 remains normal
- P50 decreased
✔✔Polycythemia O2 content - ✔✔- 26.57 mls O ml blood
✔✔Anemia O2 content - ✔✔- 13.44 mls O ml blood
✔✔Venous O2 content - ✔✔- 15 mls O ml blood
- tissue consumes appr. 5 mls
- 75% Hb sat.
✔✔O2 delivery to tissure - ✔✔- 250 mls O2 / min
- CO x (art. O2 - ven. O2)
- O2 demand per min ~ 250 mls O2
✔✔Pulse oximetry - ✔✔- measures R/IR ratio
- 0.5 = 100% sat.
- 1.0 = 82% sat.
✔✔RBCs in pulmonary capillaries - ✔✔- traverse 3 alveoli
- in pulm. capil. bed ~ 0.75 sec
- diffusion complete after ~0.25 sec or one alveoli
✔✔Pulmonary blood pressure - ✔✔- 14 mmHg - low pressure
- high flow
- high compliance
✔✔Pulmonary capillary recruitment - ✔✔- 75 ml at norm. to 200 + ml during exercise
- capillaries that were previously without perfusion are recruited
- distention dialtes blood vessels further allowing for increased blood volume
✔✔V/Q ratio - ✔✔- ventilation perfusion ratio
✔✔V/Q normal - ✔✔- 0.8
- 4.2 l/min AV / 5.5 l/min CO
✔✔V/Q shunt - ✔✔- 0
- perfused but no ventilation
, ✔✔V/Q PE - ✔✔- infinity
- ventilated but no perfusion
✔✔Causes of hypoxemia - ✔✔1) hypoventilation
2) altitude
3) diffusion limitation
4) shunt
5) V/Q mismatch
✔✔Low flow disorder - ✔✔- PE
- V/Q = infinity
✔✔High pressure disorder - ✔✔- Left sided heart failure
- Pulmonary hypertension
- Postprandial dyspnea
✔✔Left sided heart failure - ✔✔- decreased left ventricle EF causes blood to back up in
lungs
- increases hydrostatic pressure in lungs
- pushing fluid out into the alveoli
- pulmonary edema
✔✔Pulmonary hypertension - ✔✔- hypertension within pulmonary circulation
- causes pulmonary edema
- Phen/Fen prescribed in the 90s caused it
✔✔Postprandial dyspnea - ✔✔- increased blood volume in lungs due to laying supine
after large meal
- higher pulmonary pressure pushes fluid into alveoli
- stomach size redces ability of diaphragm to contract
- equals dyspnea
✔✔Pulmonary edema - ✔✔- increased path of diffusion
- surfactant lost
- obstructive disorfer
- causes shunting
✔✔Fluid movement in lungs - ✔✔- low perfusion pressure pushes small amounts of
fluid into interstitium
- mostly re-absorbed into capillary
- some drained by lymphatics
✔✔Early stage/interstitial edema - ✔✔- increases diffusion difference for O2 and CO2
between alveoli and plasma
