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Discussion Starter · #1 ·
A 27 year old man with history of bipolar I disorder woke up at night after hearing the telephone ringing. When he walked to the telephone he felt dizzy and fainted. Brought to the emergency by his wife he was awake and fully conscious. Wife did not notice any abnormal movements, cyanosis, or incontinence to urine or stool. No history of prior similar episodes. His psychiatrist adjusted his medication recently. Physical examination and lab results were all within normal limits.
What could have provoked his fainting episode?
A- Postural hypotension
B- Hypothyroidism
C- Dehydration
D- Atonic seizure
E- Prolonged QT
 

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Lithium causing Torsade!

This is a nice question,

Am thinking that Lithium has caused a prolonged QT which has predisposed him to Torsade de Pointes and this case the correct answer is E.
 

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I think this is Atonic seizure coz
1. its sudden loss of muscle tone
2. very brief loss of neurologic function
3. seizure last few seconds ..
4. usually occurs during walking , standing

Lithium ... cause
1. decrease ADH effect .. causes increase body osmolarity ... increase Na conc
2. it causes hypothyroidism ...
2. it cause torsades ... but usually prsents with EKG change - V. Fib and V tach ... with electrolyte abnormality ... but here labs are normal

a. postural hupotension usually develop on standing and with volume loss or drugs like diuretics , alpha blokade drugs , ACE - I .. as all these cause vaso dilation ..
b. here no s/s of hypothyroidism
c. cant develop dehydration this rapidly without acute significant volume loss.
e. prolong QT ( torsades ) has electrolyte and EKG change .... Vfib ( no pulse and no respiration ) and V tach( dizziness , CHF , syncope , dyspnea ) .. patient presents with significant sumptoms and signs ...
 

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Discussion Starter · #5 ·
e. prolong QT ( torsades ) has electrolyte and EKG change .... Vfib ( no pulse and no respiration ) and V tach( dizziness , CHF , syncope , dyspnea ) .. patient presents with significant sumptoms and signs ...
Prolonged QT syndrome (which can be caused by Lithium) is not always presented with outright VF at all times. Most common presentation is a temporary arrhythmia and the patient will have normal EKG except for the prolonged QT. That's they put Holter monitoring for most of the patients.
 

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Yes initially in sinus rhythm its usually present with normal EKG except Long QT .... which usually presents with hypotension and fainting ......
 
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