VIVA: Clinical Building Blocks

Question 1

Describe and interpret this VBG

Answer 1

• Primary metabolic acidosis* / HAGMA (AG 34)
• Respiratory compensation*, predicted CO2 20
• Severe hyperglycaemia*
• AG >20
• Mild hypochloraemia
• Corrected Na+ 142 and K+ 4.1 and uncorrected values within normal reference range
• Delta-ratio 1.25 consistent with pure HAGMA

Most likely diagnosis is DKA*

• Primary metabolic acidosis with respiratory compensation and glucose abnormalities to pass

Question 2

What are the priorities of treatment for DKA?

Answer 2

2/4 to pass:
- Careful rehydration/fluid replacement/IV fluids
- Insulin: infusion or subcutaneous depending on severity
- Electrolyte monitoring/management (managing K+ and Na+)
- Seek and treat precipitant of DKA

Question 3

Describe the interpret this ECG

Answer 3

Complete AV dissociation*
Atrial rate 60-80bpm
Slow ventricular escape rhythm 30bpm
RBBB
Left axis deviation
Nil ST changes
T wave inversion V1-3

Complete/3rd degree AV block*

• AV dissociation or CHB to be at standard

Question 4

What are the causes of complete heart block?

Answer 4

3 needed to pass:
- Ischaemic especially inferior or anterior myocardial infarction
- Cardiomyopathy
- AV nodal blocking drugs (e.g. calcium channel blockers, beta blockers, digoxin)
- Electrolyte abnormalities (e.g. hyperkalaemia)
- Idiopathic degeneration of conducting pathway (Lenegre or Lev’s disease)
- Fibrotic disorders/sarcoidosis/amyloidosis/autoimmune disease
- Post cardiac surgery, ablation or PCI