Goljan 1 - Goljan Flashcards Preview

USMLE > Goljan 1 - Goljan > Flashcards

Flashcards in Goljan 1 - Goljan Deck (499)
Loading flashcards...
1

PO2

driving force for diffusion of O2 into tissue

2

SaO2

percent heme groups occupied by O2

3

Cyanosis

decreased O2 saturation (SaO2); O2 content

4

Oxygen

electron acceptor in oxidative pathway

5

Hypoxia

inadequate O2 leads to ATP depletion

6

Ischemia

decreased arterial (or venous) blood flow

7

Respiratory acidosis

retention of CO, always decreases PaO2

8

Ventilation defect

impaired delivery of O2 to alveoli; intrapulmonary shunting of blood (e.g., RDS)

9

Perfusion defect

absent blood flow to alveoli; increased alveolar dead space (e.g., pulmonary embolus)

10

Diffusion defect

O2 cannot cross alveolar-capillary interface; interstitial lung disease (e.g., sarcoidosis)

11

Methemoglobin

? SaO2; heme Fe+3; oxidizing agents (sulfur/nitro drugs); Rx with IV methylene blue

12

Clinical methemoglobinemia

cyanosis not corrected by O2; chocolate colored blood

13

Carbon monoxide

? SaO2; left-shift O2 binding curve; inhibits cytochrome oxidase

14

Causes carbon monoxide poisoning

car exhaust, space heaters, smoke inhalation

15

S/S carbon monoxide poisoning

headache; cherry red color skin

16

Cyanide

inhibits cytochrome oxidase; systemic asphyxiant

17

Carbon monoxide + cyanide poisoning

house fires

18

Left-shifted O2 curve

? 2, 3 BPG, carbon monoxide, alkalosis, HbF, methemoglobin, hypothermia

19

Right-shifted O2 curve

? 2, 3 BPG, high altitude, acidosis, fever

20

High altitude

respiratory alkalosis enhances glycolysis; ? synthesis 2,3 BPG

21

Mitochondrial poisons

damages membrane and drains off protons; alcohol, salicylates

22

Uncoupling agents in mitochondria

drain off protons; dinitrophenol, thermogenin (brown fat)

23

Complication mitochondrial poisons/uncoupling agents

hyperthermia

24

Decreased ATP

impaired Na+/K+ ATPase pump (cellular swelling); reversible

25

Anaerobic glycolysis

ATP synthesis in hypoxia; lactate ? intracellular pH, denatures proteins

26

Irreversible injury hypoxia

membrane/mitochondrial damage

27

Mitochondrial damage

release cytochrome c activates apoptosis

28

Irreversible injury hypoxia

? cytosolic Ca2+ activates phospholipase, proteases, endonuclease

29

Free radicals

unpaired electron in outer orbit; damage cell membranes and DNA

30

Free radicals

superoxide, hydroxyl, peroxide, drugs (acetaminophen)