Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharmacy Stage 2 > Acid-Base and Blood Gasses > Flashcards

Acid-Base and Blood Gasses Flashcards

1
Q

with less CO2 partial pressure what happens to ventilation rate?

A

decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what metabolic processes produce significant amounts of hydrogen?

A
  1. digestion of foods
  2. metabolism of drugs
  3. errors within metabolism
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what organ is responsible for excreting hydrogen ions through the urine?

A

the kidneys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What two energy substrates produce hydrogen ions when oxidised incompletely?

A

lactic acid and the metabolism of fats (triacylglycerols)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what metabolic reaction uses up hydrogen ions?

A

oxidative metabolism of ketones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

how is carbon dioxide produced?

A

as a product of oxidative metabolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

how is CO2 excreted?

A

by ventilation (expired air)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What equation shows how CO2 contributes to H+ production?

A

CO2+H2O H2CO3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is normal body extracellular fluid pH maintained between?

A

7.35-7.46

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the equation of the body’s buffering system?

A

H+ + HCO3 H2CO3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

how does renal filtration of Na+ and HCO3- work?

A
  1. Na+ and HCO3- are filtered in the glomerulus
  2. renal tubule cells secrete H+ in exchange for Na+.
  3. CO2 is formed by the reaction of HCO3-with H+ and diffuses into the tubule.
  4. CO2 coverted back into HCO3 in the renal tubule cell.
  5. Na+/HCO3- symporter carry Na+ and HCO3- across basal membrane of tubule cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what two things are secreted and excreted from the kidneys after filtration?

A

NH4+ and H+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is metabolized to release NH4+ and HCO3- in the kidneys?

A

glutamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

how does the phosphate buffer system work in the renal tubule?

A
  1. H2O and CO2 combine to form H2CO3.
  2. H2CO3 breaks down into HCO3- nd H+
  3. H+ leaves the renal tubule and enters the tubular lumen
  4. it binds to HPO4(2-) in the lumen to form H2PO4-
  5. as H+ leaves, Na+ enters the cell
  6. Na+ leaves via ATPase transporter which pumps K+ in at the same time.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

how does the protein buffer system work?

A

(at the tissues)
1. CO2 and H2O form HCO3- and H+ which binds with Hb from HbO2 dissociating into O2 and Hb.
2. HCO3- leaves the red blood cell and Cl- enters.
3. CO2 and Hb combine to form HbCO2
(then the reverse of all the reactions take place at the lungs-slide 13 for more details)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

how does the carbonic acid-bicarbonate buffer system work?

A
  1. Na+ - H+ antiport secretes H+
  2. H+ combines with HCO3- forming CO2 and H2O
  3. CO2 diffuses into the cell and combines with H2O forming HCO- and H+
  4. H+ is secreted and excreted
  5. HCO3- is reabsorbed
  6. glutamine is metabolised into ammonium ions and HCO3-
  7. NH4+ is secreted and excreted
  8. HCO3- is reabsorbed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

two buffer systems that occur in the intracellular fluid (ICF)

A
  1. phosphate buffer system

2. protein buffer systems

18
Q

two buffer systems that occur in the ECF?

A
  1. carbonic acid-bicarbonate buffer system.

2. protein buffer systems

19
Q

What are the three types of protein buffer systems?

A
  1. haemoglobin buffer systems (RBCs)
  2. amino acid buffers (all proteins)
  3. Plasma protein buffers
20
Q

what equation links [H+], PCO2 and [HCO3-]?

A

[H+] = k (PCO2/[HCO3-])

21
Q

how do you calculate anion gap?

A

(Na+K) - (Cl+HCO3)

22
Q

what is acidosis and alkadosis?

A

acidosis - high H+ conc

alkalosis - low H+ conc

23
Q

four components that influence non-respiratory acidosis?

A
  1. H+ generation
  2. Buffering
  3. Compensation
  4. Correction
24
Q

what causes non-respiratory acidosis?

A
  1. increased [H+]
  2. Decreased excretion
  3. Decreased [HCO3-]
25
Q

what causes increased H+ concentration?

A
  1. diabetic ketoacidosis due to lack of insulin so fatty acids are metabolised. Excess glucose causes dehydration
  2. aspirin poisoning causes acidosis as well.
26
Q

how does decreased excretion of H+ cause acidosis?

A
  1. decreased GFR reduces sodium ion filtration, hence less H+ can be excreted as less Na+ to exchange with. So H+ ions accumulate.
  2. decreased GFR also means reduced phosphates hence mechanism for H+ ion clearance is compromised.
27
Q

what happens when H+ concentration rises?

A
  1. it is buffered by the bicarbonate whose conc falls as it makes carbonic acid (H2CO3).
  2. carbonic acid dissociates producing carbon dioxide which is lost on expiration.
  3. non-respiratory acidosis develops
  4. respiratory centre is stimulated causing hyperventilation to remove more CO2
  5. producing a compensatory alkalosis
28
Q

how is non-respiratory acidosis treated?

A
  1. removal of the underlying problem.

2. bicarbonates used with care in patients with pH <7

29
Q

what causes respiratory acidosis?

A
  1. airway obstruction
  2. depression of respiratory centre
  3. neuromuscular disease
  4. Pulmonary disease
  5. Extra pulmonary thoracic disease
30
Q

what are all respiratory acidosis characterised by?

A

increase in PCO2

31
Q

although H+ concentration increases in respiratory acidosis, why does the pH still fall?

A

because the HCO3- conc increases also which would then neutralise the H+

32
Q

what is hypoxemia?

A

low oxygen levels

33
Q

what is hypercapnia?

A

high CO2 levels

34
Q

what is non-respiratory alkalosis?

A

an increase in bicarbonate levels

35
Q

what causes non-respiratory alkalosis?

A
  1. excess alkali administration

2. loss of free hydrogen

36
Q

what happens during respiratory alkalosis?

A

PCO2 increases in order to increase H+ concentration.

37
Q

how do we manage respiratory alkalosis?

A
  • infusion of normal saline solution

- taking potassium supplements

38
Q

what is respiratory alkalosis?

A

a decrease in PCO2 levels

39
Q

what causes respiratory alkalosis?

A
  1. hypoxia - increased CO2 loss

2. increased drive: infections, hyperventilation, cerebral malignancy etc.

40
Q

how is respiratory alkalosis treated?

A
  1. remove underlying cause

2. if hyperventilation in the cause, re-breathe CO2 in

Pharmacy Stage 2 (85 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions