Acid-base balance

Question 1

H+ range:

Answer 1

36-43nmol/L

Question 2

Severe acidosis _____pH

Answer 2

<7.2

Question 3

Acidosis effects

Answer 3

Peduces cardiac contractility
Peripheral vascular resistance
Progressive hypotension
Ventricular fibrillation threshold is decreased
Hyperkalemia
CNS depression

Question 4

Excretion of CO2 by alveolar ventilation

Answer 4

minimum 12000mmol/day

Question 5

Reabsorption of filtered HCO3

Answer 5

4000-5000mmol/day

Question 6

Physiological buffers:

Answer 6

Bicarbonate (H2CO3/HCO3)
Hemoglobin (HbH/Hb-)
Intracelullar proteins (PrH/Pr-)
Phosphates (H2PO4-/HPo42-)
Ammonia (NH3/NH4+)

Question 7

Bicarbonate is the most important buffer in _______
Hemoglobin, though restricted inside red blood cells, also functions as an important buffer in ______
___________ are important urinary buffers

Answer 7

Extracellular fluid
Blood
Phosphate and ammonium

Question 8

Acid loads do what to bone?

Answer 8

Demineralize bone and release alkaline compounds (CaCO3 and CaHPO4)

Question 9

Hg is rich in _________ an effective buffer

Answer 9

Histadine

Question 10

Renal response to acidity:

Answer 10

Increase reabsorption of HCO3-
Increased excretion of titratable acids
Increased production of ammonia

Question 11

Respiratory acidosis numbers, cause, etiology:

Answer 11

ph<7.35 and PaCO2>45mm/Hg
Suppression of the respiratory center, opiates, obesty, nerve or muscle disorders
Respiratory tract diseases - COPD, asthma, ARDS

Question 12

Hypercapnoic acidosis causes

Answer 12

Insufficient mechanical ventilation

Question 13

Metabolic acidosis mechanisms:

Answer 13

• Consumption of HCO3- by a strong nonvolatile acid
• Renal or GI wasting of bicarbonate
• Rapid dilution of the extracellular fluid compartment w/ a bicarbonate-free fluid

Question 14

Metabolic acidosis numbers:

Answer 14

<22mmol/L HCO3-
pH<7.35

Question 15

Anion gap calculation:

Answer 15

AGap = ([Na+] - ([Cl-] + [HCO3-])

Question 16

Base excess:

Answer 16

Defined as the amount of acid or base that must be added for blood pH to return to 7.4 and PaCO2 to return to 40mmHg at full O2 saturation and 37C

Question 17

Respiratory alkalosis causes:

Answer 17

Central - head injury, pain, anxiety, progesterone
Hypoxemia -

Question 18

pH
HCO3
pCO2

Answer 18

7.35-7.45
35-45
22-26

Question 19

Total energy expenditure

Answer 19

TEE = BEE x stress factor x activity factor

Question 20

CHO is ______% of calories
Fats are _____% of calories

Answer 20

50-75
25-30

Question 21

Nacl danger:

Answer 21

Hyper-choloremic acidosis