Clinical Cutoffs/parameters

Question 1

Indications LTOT

Answer 1

PaO2< 7.3 or

PaO2 7.3 - 8 with cor pulmonale or polycythaemia

Question 2

Transudate and exudate

Answer 2

Exudate> 35g/L
Transudate <30g/L

Light’s criteria
If pleural fluid protein level between 30 and 35 g/L (i.e.borderline) use Light’s criteria – exudate if one or more of the following:
Pleural fluid/Serum protein >0.5
Pleural fluid/Serum LDH >0.6
Pleural fluid LDH > 2/3 of the upper limit of normal

Question 3

Indications for Acute Dialysis

Answer 3

Persistent hyperkalemia >7mM
Refractory pulmonary oedema
Symptomatic uraemia: encephalopathy, pericarditis
Severe metabolic acidosis pH <7.2
Poisoning e.g. Aspirin

Question 4

Renal failure

Answer 4

Stage 1 >90 (eGFR)
Stage 2 60-89
Stage 3a 45-59
Stage 3b 30-44
Stage 4 16-29
Stage 5 <15

Question 5

Stop metformin when?

Answer 5

Creatinine above 150 µmol/L

Question 6

Urology referral criteria - urgent and routine

Answer 6

Urgent referral (i.e. within 2 weeks)

Aged >= 45 years AND:
unexplained visible haematuria without urinary tract infection, or
visible haematuria that persists or recurs after successful treatment of urinary tract infection

Aged >= 60 years AND have unexplained nonvisible haematuria and either dysuria or a raised white cell count on a blood test

Non-urgent referral

Aged 60 >= 60 years with recurrent or persistent unexplained urinary tract infection

Since the investigation (or not) of non-visible haematuria is such as a common dilemma a number of guidelines have been published. They generally agree with NICE guidance, of note:
patients under the age of 40 years with normal renal function, no proteinuria and who are normotensive do not need to be referred and may be managed in primary care

Question 7

Diabetes cut offs

Answer 7

Plasma glucose

Fasting (8hr) normal <6; impaired 6-7; diabetes >7mmol/l

Post prandial (2hr post 75g glucose load) normal <7.8; impaired 7.8-11; diabetes >11mmol/l

Question 8

Criteria for safe asthma discharge

Answer 8

PEFR >75%
Stop regular nebulisers for 24 hours prior to
discharge
Inpatient asthma nurse review to reassess inhaler
technique and adherence
Provide PEFR meter and written asthma action plan
At least 5 days oral prednisolone
GP follow up within 2 working days
Respiratory Clinic follow up within 4 weeks
For severe or worse, consider psychosocial factors

Question 9

Chronic limb ischaemia

Answer 9

Ankle artery pressure <50mmHg
AND either:
Persistent rest pain requiring analgesia for >2 weeks or
Ulceration/ gangrene

Question 10

Critical limb ischaemia

Answer 10

Rest pain
Ulceration
Gangrene

Question 11

Buerger’s angle

Answer 11

> 90 normal
20-30 ischaemia
<20 severe ischaemia

Question 12

ABPI

Answer 12

Calcification >1.4
Normal > 1
Asymptomatic (Fontaine 1) 0.8-0.9
Intermittent claudication (Fontaine 2) 0.6 - 0.8
Rest pain (Fontaine 3) 0.3 - 0.6
Gangrene and ulceration (Fontaine 4) <0.3

Question 13

Endarterectomy

Answer 13

Symtpomatic (ECST, NASCET):
70-99%
>50% if low risk
perform within 2wks of presentation

Asymptomatic (ACAS, ACST)
>60% benefit if low risk

Question 14

Aneurysm

Answer 14

Dilation of blood vessel >50% its normal diameter

Question 15

AAA monitoring

Answer 15

<4cm yearly US

4-5.5: six monthly US

Question 16

ABPI for 4 layer graded compression bandage

Answer 16

> 0.8

Question 17

Jaundice visible at what bilirubin concentration

Answer 17

50uM (normal 3-17)

Question 18

AST:ALT ratios and cause

Answer 18

AST:ALT >2 = EtOH
AST:ALT<1 = Viral

Question 19

Serum Ascites Albumin Gradient (SAGG)

Answer 19

SAAG >1.1g/dL = portal HTN (cirrhosis in 80%)

SAAG <1.1G/dL = Other causes (neoplasia, inflammation, infection, nephrotic syndrome)

Question 20

ECG territories and coronary arteries

Answer 20

Anteroseptal = V1-4 (LAD)
Lateral = V5-6 (Cx)
High Lateral = I, aVL (Cx)
Inferior = II, III, aVF (RCA)

Question 21

How to calculate alcohol units.

For example, to work out the number of units in a pint (568ml) of strong lager (ABV 5.2%):

Answer 21

strength (ABV) x volume (ml) ÷ 1,000 = units

e.g. 5.2 (%) x 568 (ml) ÷ 1,000 = 2.95 units

Question 22

MMSE scores and dementia severity

Answer 22

25-30 Normal
21-24 Mild
10-20 Moderate
<10 Severe

Question 23

Asthma exacerbation levels

Answer 23

Near fatal
Life threatening
Severe
Moderate

Question 24

MMSE scores

Answer 24

Normal 25-30
Mild 21-24
Moderate 10-20
Moderate severe 10-14
Severe <10

Question 25

Lithium therapeutic index and toxicity levels

Answer 25

Normal 0.6-1.0 (aim for 0.8)

Toxicity - anything over 1.2

Question 26

Normal protein excretion

Answer 26

<150mg/day

Although urine dipstick unreliable as are 24hr collections - use protein or albumin:creatinine ratios on early morning MSU

Question 27

Impaired glucose tolerance

Answer 27

Impaired glucose tolerance (IGT) is defined as fasting plasma glucose less than 7.0 mmol/l and OGTT 2-hour value greater than or equal to 7.8 mmol/l but less than 11.1 mmol/l

Question 28

Impaired fasting glucose

Answer 28

A fasting glucose greater than or equal to 6.1 but less than 7.0 mmol/l implies impaired fasting glucose (IFG)

Question 29

Primary pneumothorax - cut off for aspiration and chest drain

Answer 29

if the rim of air is < 2cm and the patient is not short of breath then discharge should be considered
otherwise aspiration should be attempted
if this fails (defined as > 2 cm or still short of breath) then a chest drain should be inserted

Question 30

Secondary pneumothorax - cut off for aspiration/ drain/ observation

Answer 30

if the patient is > 50 years old and the rim of air is > 2cm and/or the patient is short of breath then a chest drain should be inserted.

otherwise aspiration should be attempted if the rim of air is between 1-2cm. If aspiration fails (i.e. pneumothorax is still greater then 1cm) a chest drain should be inserted. All patients should be admitted for at least 24 hours

if the pneumothorax is less the 1cm then the BTS guidelines suggest giving oxygen and admitting for 24 hours

Question 31

How long before can drive post MI?

Answer 31

4 weeks

Question 32

SIADH

Answer 32

Hyponatraemia associated with elevated urine osmolality with urine sodium above 20 mmol/l and a low plasma osmolality.

(Aassociated with diseases such as pneumonia, bronchial small cell cancer, subarachnoid haemorrhage , pulmonary TB, meningitis, head injury, intermittent porphyria)

Question 33

Pre-diabetes HbA1c

Answer 33

Prediabetes is defined by a HbA1c of 42-47 mmol/mol (6.0-6.4%)

Question 34

COPD severity FEV1 % predicted

Answer 34

Mild FEV1> 80% predicted
Moderate 50-80%
Severe 30-50%
Very severe <30%

Question 35

Aortic valve replacement at what pressure gradient?

Answer 35

> 50mmHg

Question 36

Ejection fraction ratios?

Answer 36

Normal = 50-70%
Borderline = 41-49%
Heart failure or cardiomyopathy <40
Hypertrophic cardiomyopathy >75%

Question 37

Degree of aortic stenosis

Answer 37

Mild <25mmHg
Mod 25-40 mmHg
Sev >40 mmHg
Critical >50mmHg

Question 38

DEXA scoring

Answer 38

T score - comparison to young referenced mean.

+1 to -1 = Normal

-1 to - 2.5 = osteopenia

<2.5 = osteoporosis

(Z score - comparison to people of same age)

Question 39

DKA criteria

Answer 39

Glucose >11mmol/L
blood pH <7.3 or HCO3 <15
capillary ketones >3mmol or urinary ketones ++

Question 40

INR therapeutic targets

Answer 40

INR 2-3: DVT/PE, hypercoagulable states, AF

INR 2.5-3.5: aortic metallic heart valves

INR 3-4: mitral metallic heart valves

Question 41

Normal maintenance requirements if NBM

Answer 41

H20+ 1.5ml/kg/h
Na +1-2mmol/kg/24h
K+ 0.5-1mmol/kg/24

urine output should be >0.5ml/kg/24h

Question 42

Treatment dose LMWH for PE

Answer 42

1.5mg/kg

Question 43

Concentrated and dilute urine

Answer 43

Concentrated urine osmolality >300mosm/kg

Dilute urine osmolality <250mosm/kg

Question 44

Metformin prescribing and kidney problems

Answer 44

In adults with type 2 diabetes, review the dose of metformin if the estimated glomerular filtration rate (eGFR) is below 45 ml/minute/1.73m2:
Stop metformin if the eGFR is below 30 ml/minute/1.73m2
Prescribe metformin with caution for those at risk of a sudden deterioration in kidney function and those at risk of eGFR falling below 45ml/minute/1.73m2