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Normal Ranges > Blood Gases > Flashcards

Flashcards in Blood Gases Deck (22):
1

pH

7.35 - 7.45

2

PO2

10 - 14 kPa

3

PCO2

4.5 - 6 kPa

4

Base excessive

-2 - 2 mmol/l

5

HCO3

22 - 26 mmol/l

6

1

Acidaemia or alkalaemia?

7

Look at pco2 and bicarb

If either abnormal may be mixed

8

Co2 changes

Resp

9

Bicarb changes

Metabolic

10

Resp alkalosis

Pneumothorax
Asthma
PE
Hypervent
Pneumonia
Pulmonary oedema

11

Met alkalosis

Gi - vom/diarrhoea
Renal - Conn's, Cushing's, loop or thiazide diuretic, post hypercapnic
Hypokalaemia
Diuretics: h ion loss of contraction

12

Normal anion gap

8-16

13

Anion gap

Reflects unmeasured anions

Na-(hco3+cl)

14

High anion gap

Incr acid:
Exog: methanol, aspirin, ethylene glycol
Renal failure
Ketoacidosis: alcohol, starvation, diabetes
lactic acidosis: type a tissue hypoperfusion, b

15

Compensation

Ventilatory response: mins - hrs (resp)
Renal response: days (metabolic)

16

Chronic resp acidosis

High bicarb to concentrate

17

Acute resp acidosis

Bicarb normal can't compensate quickly

18

Acute metabolic acidosis

Low CO2 to compensate

19

Metabolic alkalosis

Hypovent to compensate
CO2 incr

20

Simple acid base disorders

pH will be abnormal
Bicarb follows CO2

21

Resp acidosis

COPD,pneumonia, asthma, pulm oedema
Obstructive sleep apnoea,
Obesity, kyphosis, flail, scleroderma
Mnd

22

For every 1.3 incr in pco2 above 5.3

Hco3 incr by 3.5