Investigations

Question 1

What tests should be done to investigate TLoC?

Answer 1

• ECG
• BP (lying + standing)
• U+E, FBC, Mg, Ca, Na, glucose
• Tilt table test (not for vasovagal syncope)
• EEG (+ sleep)
• Echo
• CT/MRI brain
• ABG if practical

Question 2

What should be asked in the history of a TLoC?

Answer 2

• Details of event from patient and witness
• Any previous blackouts
• PMH (esp. cardiac)
• FH (esp. cardiac/sudden cardiac death)
• Review current medication

Question 3

How should diagnosis of orthostatic hypotension be done?

Answer 3

Fall in systolic BP of 20mmHg (30mmHg in HTN) +/or fall in diastolic BP of at least 10mmHg within 3 mins of standing

Question 4

How do you identify an underlying cardiac cause?

Answer 4

• ECG abnormality
• Evidence of HF, blackouts occurring during exertion, palpitations before LOC
• FH of sudden cardiac death in people <40yrs +/or inherited cardiac condition, new or unexplained breathlessness +/or heart murmur

Question 5

What are the investigations for epilepsy?

Answer 5

• History
• EEG (to support history, not for diagnosis, potentially to determine seizure type)
• Drugs levels (AEDs to assess compliance)
• Drug screen
• Blood + urine tests (to determine underlying cause)
• ECG (when there is diagnostic uncertainty)
• Should be referred to specialist for neurological assessment within 2 weeks