Week 8a: acid base balance

Question 1

normal pH

Answer 1

7.35-7.45

Question 2

normal PaO2

Answer 2

80-100mmHg

Question 3

normal PaCO2

Answer 3

35-45

Question 4

HCO3

Answer 4

21-25mmol/L

Question 5

Normal base excess

Answer 5

-2 - +2

Question 6

high anion gap =

Answer 6

acidosis

Question 7

base excess more than +2 =

Answer 7

metabolic alkalosis

Question 8

base excess less than -2 =

Answer 8

metabolic acidosis

Question 9

normal anion gap

Answer 9

8-16mmol/L

Question 10

signs and symptoms of metabolic acidosis

Answer 10

• increased respiratory rate and depth
• acidic urine
• weakness, fatigue, nausea and vomiting
• later signs: decreased LOC, decreased CO, coma and death

Question 11

for treatment of metabolic acidosis, why is sodium bicarbonate not always indicated?

Answer 11

it can cause hyperosmolarity and hypoxia

Question 12

what is the primary disturbance in metabolic acidosis?

Answer 12

decrease in bicarbonate, DKA, sepsis, severe diarrhea, renal failure, shock

Question 13

respiratory compensation in metabolic acidosis?

Answer 13

hyperventilation to decreased PCO2

Question 14

renal compensation in metabolic acidosis?

Answer 14

if no renal disease, then increased H+ excretion and increased HCO3 reabsorption

Question 15

what is the primary disturbance in metabolic alkalosis?

Answer 15

decrease in bicarbonate

Question 16

respiratory compensation in metabolic alkalosis?

Answer 16

hypoventilation to increase PCO2

Question 17

renal compensation in metabolic alkalosis?

Answer 17

if no renal disease, decrease in H+ excretion and decrease in HCO3 reabsorption

Question 18

what are the causes of metabolic alkalosis?

Answer 18

alkaline ingestion, gastric suction, hypokalemia, loss of body fluids (diuretics), high lactate (ringers lactate)

Question 19

signs and symptoms of metabolic alkalosis?

Answer 19

decreased respirations, hypotension, alkaline urine, confusion, convulsions, arrhythmias, tetany

Question 20

what is one of the main treatments for metabolic alkalosis?

Answer 20

sodium chloride (mild) or ammonium chloride (severe)

Question 21

what is the primary disturbance in respiratory acidosis ?

Answer 21

increase in PCO2

Question 22

is there respiratory compensation in respiratory acidosis?

Answer 22

no

Question 23

renal compensation in respiratory acidosis

Answer 23

increased H+ excretion and increased HCO3 reabsorption

Question 24

causes of respiratory acidosis?

Answer 24

lung disease (COPD, pulmonary edema), hypoventilation in hospitalized ventilated patients, bradypnea (drug overdose), sepsis, trauma (burns and head injury)

Question 25

signs and symptoms of respiratory acidosis?

Answer 25

changes in LOC, headache (due to vasodilation), confusion/paranoia/hallucinations (due to hypoxia), flushed skin (vasodilation)

Question 26

primary disturbance in respiratory alkalosis?

Answer 26

decrease in PCO2

Question 27

is there respiratory compensation in respiratory alkalosis?

Answer 27

no

Question 28

renal compensation in respiratory alkalosis

Answer 28

decreased H+ excretion and decreased HCO3 reabsorption

Question 29

causes of respiratory alkalosis?

Answer 29

hyperventilation due to increased mechanical ventilation, panic/anxiety, fever, encephalitis, compensation due to hypoxia and drug toxicity (ASA)

Question 30

a urine output of _____ may indicate hypovolemia

Answer 30

0.5mg/kg/h

Question 31

what are some signs of hypervolemia?

Answer 31

hypertension, bounding pulse, pulmonary crackles, dyspnea, SOB, peripheral edema, JVD and extra heart sounds such as S3

Question 32

which IV solution is the fluid of choice for resuscitation efforts?

Answer 32

normal saline

Question 33

which IV solution is used to replace fluid loss from hemorrhage, severe vomiting or diarrhea, heavy drainage from GI suctioning, fistulas or wounds?

Answer 33

normal saline

Question 34

which IV solution is the fluid of choice for resuscitation of burn and trauma patients?

Answer 34

ringers lactate

Question 35

Which IV solution is used to treat acute blood loss or hypovolemia due to 3rd space fluid shift; GI loss and fistula drainage, electrolyte loss and metabolic acidosis ?

Answer 35

ringers lactate

Question 36

which IV solution is both isotonic and hypotonic?

Answer 36

D5W

Question 37

which IV solution provides free water for the kidneys, aiding in renal excretion of solutes and may be used to treat hypernatremia

Answer 37

D5W

Question 38

which type of solutions are typically used to treat conditions causing intracellular dehydration such as DKA and hyperosmolar hyperglycaemic states

Answer 38

hypotonic

Question 39

what type of solutions may worsen existing hypovolemia and hypotension causing cardiovascular collapse?

Answer 39

hypotonic

Question 40

which type of solutions may be used to correct critical electrolyte abnormalities?

Answer 40

hypertonic

Question 41

which type of solutions may cause fluid volume overload and pulmonary edema

Answer 41

hypertonic

Question 42

which type of solutions should be avoided in patients with cardiac or renal conditions who are dehydrated and in patients with DKA?

Answer 42

hypertonic