acid base balance

Question 1

what is an acid

Answer 1

proton donator

Question 2

what is a base

Answer 2

proton acceptor

Question 3

what is a buffer

Answer 3

• a solution containing substances which can minimise changes in PH

Question 4

intracellular buffering components examples

Answer 4

• physiochemical include proteins, phosphates
• metabolic
• organeller
• acid extrusion

Question 5

extracellular buffering components

Answer 5

• physiochemical include hb, albumin, bicarbonate
• metabolic such as changing ventilation rate

Question 6

what is the normal blood ph

Answer 6

7.35-7.45

Question 7

what is an volatile acid and example

Answer 7

• carbonic acid dissociates into carbon dioxide and water which can be expelled during expiration as a gas
• volatile acid can be expelled as a gas through the lungs

Question 8

non volatile acid examples

Answer 8

• all acids other than carbonic acid
• excreted in urine
• usually referred to their anion base e.g. lactate, sulphate
• derived from oxidation of CHO fats and amino acids

Question 9

what is the buffer of the blood

Answer 9

• H+ + HCO3- > H2CO3 > H20 + CO2
• HCO3- acts as the base and binds with an free H+ ions minimising changes in ph of the blood
• hydrogen ions also buffered by hb and other proteins

Question 10

what is acidosis and the two types of acidosis

Answer 10

• ph in blood is low so below 7.35
• metabolic acidosis
• respiratory acidosis

Question 11

what is metabolic acidosis

Answer 11

• low ph
• low levels of base specifically bicarbonate ions

Question 12

what is the 5 cause of metabolic acidosis

Answer 12

• too much acid ingested e.g. aspirin overdose
• too much acid produced diabetes ketoacidosis, lactate acidosis
• too much base excreted- small bowel fistula
• too little acid excreted- renal failure
• too little base produced- renal failure

Question 13

what is respiratory acidosis

Answer 13

• low ph
• high partial pressures of carbon dioxide
• hypoventilation
• compensatory to metabolic alkalosis and drugs
• inability to clear co2 due to lung pathology such as copd, pneumonia, muscle weakness

Question 14

what is the anion gap

Answer 14

• difference between unmeasured anions and cations
• [na+] + [k+]- [hco3-] - [cl-]
• anion gap is 8-16 mol/l usually
• gives indication of cause of metabolic acidosis

Question 15

what does an increased anion gap suggest

Answer 15

• associate with too much acid being produced/accumulation of acids
• renal failure
• ingestion of acid
• diabetic ketoacidosis (too much acid produced)
• lactic acidosis ( too much acid produced)

Question 16

what does an normal anion gap suggest

Answer 16

• suggests acidosis might be due to loss of bicarbonate ions or other non- acid causes
• decreased acid excretion
• loss of base (diarrhoea, small bowel fistula)
• normal anion gap associated with hypercholraemia (high chloride levels- can cause hco3 levels to be excreted to compensate increased cl- levels

Question 17

how does exercise cause acidosis

Answer 17

• tissues undergoing respiration- aerobic
• demand of oxygen exceeds supply so anaerobic respiration takes place
• lactate produce as well as hydrogen ions
• leads to lactate acidosis

Question 18

how does type 1 diabetes cause acidosis

Answer 18

• no insulin produced
• glucose not utilised as a source or energy
• fats are utilised
• ketone acids form which leads to ketoacidosis

Question 19

what is alkalosis and the two types

Answer 19

• ph is too high
• metabolic alkalosis
• respiratory alkalosis

Question 20

what is metabolic alkalosis

Answer 20

• high ph
• high bicarbonate levels
• base excess

Question 21

what is 3 the causes of metabolic alkalosis

Answer 21

• too much base being produced e.g. compensatory to respiratory acidosis
• too much base ingested e.g. antacids
• too much acid excreted e.g. vomiting

Question 22

what is respiratory alkalosis

Answer 22

• high ph
• low carbon dioxide levels
• due to hyperventilation which can caused by drugs or compensatory to metabolic acidosis, anxiety

Question 23

compensatory of metabolic acidosis

Answer 23

• increased ventilation

Question 24

compensatory of respiratory acidosis

Answer 24

• renal compensation
• causing in a rise in hco3- levels

Question 25

compensatory of metabolic alkalosis

Answer 25

- decreased ventilation - hypoventilation - breath in paper bag

Question 26

compensatory of respiratory alkalosis

Answer 26

- renal compensation - increased hco3- excretion