Subarachnoid haemorrhage

 

Intro:

Definition

·     Bleeding into CSF space

Cause

1.   Trauma

2.   Aneurysm (esp AComm, PComm)

3.   Hypertension

N.B. classification systems only apply to aneurysmal SAH

Treatment

·     Clipping: if anterior circulation and/or accessible

·     Coiling: if posterior circulation and/or inaccessible (? better outcomes)

 

WFNS classification:

Pros

·     Clinical

·     Easy

·     Predicts outcome

1

·     GCS 15

2

·     GCS 13-14

·     No motor deficit

3

·     GCS 13-14

·     With motor deficit

4

·     GCS 7-12

5

·     GCS 3-6

 

Fisher classification

Pros

·     Radiological

·     Objective

·     Predicts vasospasm (grade 3 highest risk)

1

·     No blood

2

·     Subarachnoid <1mm thick

3

·     Subarachnoid >1mm thick

4

·     Intraventricular or intraparenchymal extension

 

SAH complications:

Neuro

·     Intracranial hypertension

·     Cerebral oedema

·     Obstructive hydrocephalus

·     Re-bleed (~24h – often fatal)

·     Seizures

·     Vasospasm (~1/52)

o  Dx: new focal deficit, no other cause

o  Prevention: saline, nimodipine

o  Treatment: DSA angioplasty if big vessel, DSA vasodilator if diffuse

Cardiovascular

·     ECG abnormalities

·     Arrhythmia

·     Myocardial ischaemia

·     Neurogenic APO

·     Rebound hypertension (expect ↑20-30% post-op)

Metabolic

·     SIADH

·     CSW

·     Mannitol side effects

 

If pregnant:

·        >32 -> deliver

·        24-32 -> deliver if foetal distress

·        <24 -> don’t deliver