> Actually there's no evidence that LP patients need to rest after the
> procedure - just common practice.
>
> Mark Slade
> General Medicine consultant
That is interesting if it is just common practice. The feeling in the past
was that headaches are worse and more likely if the patient mobilises early.
If that is not the case then it would make a difference to what we do.
katherine hendersons comment regarding the timing of SAH is a fair one. Paul
Wallman when he was with us (now an SpR down south somewhere) looked at this
question and found no convincing evidence (the draft BET is at the end of
this message).
Like Katherine, we tend to arrange the CT and then refer on to the medics
for the LP should this be required (if CT positive they go off to
Neurosurgery). There have been several episodes of patients being discharged
without LP by the medical teams. We don't think this is good management, so
if it could be managed in house???
Simon Carley
SpR in Emergency Medicine
Manchester Royal Infirmary
England
[log in to unmask]
Evidence based Emergency Medicine
http://www.bestbets.org
----- Original Message -----
From: Slade, Mark <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, January 02, 2001 12:15 PM
Subject: Re: TIA
> Actually there's no evidence that LP patients need to rest after the
> procedure - just common practice.
>
> Mark Slade
> General Medicine consultant
> Oxford
>
An early LP after a Lone Acute Severe Headache may not exclude SAH.
Clinical Scenario.
A 24 year old previously fit and well male presents to the A+E department
complaining of headache. He describes the headache as the worst he has ever
had. It came on suddenly approximately 2 hours previously and has not
resolved with paracetamol. He has no other neurological symptoms and
clinical examination reveals no neurological signs. You are concerned that
he may have had a sub-arachnoid hemorrhage and arrange a CT scan. The CT is
reported as normal. You perform an LP 3 hours after the onset of headache
which is also normal and the patient home after a period of observation. 5
days later the same patient returns to the department with a massive SAH and
dies. You wonder whether you performed the LP at the optimal time
Three part question
(In adults presenting with a lone acute severe headache) DOES (the
diagnostic sensitivity of LP change with time) AT (diagnosing SAH).
Search Strategy
Medline using OVID database 1966- October 1999. (exp subarachnoid
hemorrhage/ OR "subarachnoid".mp. OR "sub-arachnoid haemorrhage".mp. OR
"subarachnoid haemorrhage".mp.) AND (exp spinal puncture/ OR "lumbar
puncture".mp.) AND (exp time/ OR exp time factors/ OR "time".mp. OR "HOURS$"
.mp.) LIMIT to human AND English language
Search results
62 papers were found with the above search strategy and none answered the
particular question posed.
Comment
There is no evidence whatsoever in performing an early or late lumbar
puncture in the above scenario. It has been postulated that a lumbar
puncture is only a reliable gold standard if performed as late as 12 hours
after onset of the headache; small sub-arachnoid haemorrhages may be missed
if spinal puncture is too soon; if traumatic lumbar puncture occurs this can
only be differentiated from sub-arachnoid haemorrhage if late on. However it
has also been postulated that delay in lumbar puncture after a normal ct
scan can have potential neurological sequelae if sub-arachnoid blood is
present.
Clinical Bottom Line
In a patient with lone acute severe headache with a normal CT scan a lumbar
puncture performed within 6 or even 12 hours of onset of headache may not
exclude the diagnosis of sub-arachnoid haemorrhage.
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