Subarachnoid haemorrhage

 

Intro:

Definition

·      Bleeding into CSF space

Cause

1.    Trauma

2.    Aneurysm (esp AComm, PComm)

3.    Hypertension

Treatment

·      Clipping: if anterior circulation and/or accessible

·      Coiling: if posterior circulation and/or inaccessible

 

WFNS classification:

 

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

 

Radiological

Objective

Predicts vasospasm (esp grade 3)

1

No blood

2

Subarachnoid <1mm thick

3

Subarachnoid >1mm thick

4

Intraventricular or intraparenchymal extension

 

General issues:

Emergency surgery

·      Assume full stomach

·      Rx big dose opioid, minimise propofol, infuse metaraminol

·      Rx modified RSI; no bag-mask vent

Remote airway

·      Check ETT position at teeth

·      Auscultate

·      Secure with sleek + bilateral tegaderm

·      Ensure attachments locked well

·      Secure insp/exp tubing with artery forceps

Bleeding

·      BGHO +/- XM

·      ≥18g cannula x 2

·      Fluid warmer + forced air warmer

·      Avoid hypertension

Microsurgery

·      No movement, no coughing

·      High dose opioid

·      Relaxant at PTC 2

 

Neuro issues:

Unsecured aneurysm

Avoid further rupture:

·      Preserve transmural gradient (mAP – ICP)

·      Avoid ↑↑mAP or ↓↓mAP

·      Rx high dose opioid + metaraminol infusion

Facilitate surgical access:

·      Propofol

·      Opioid

·      Vasodilators

·      Adenosine

Tight brain

Maintain mAP:

·      Fluid + pressor

·      Aim 80-90

·      Transducer at tragus

Minimise ICP:

·      Physical: head up 30°, loosen things around neck

·      Physiological: O2, CO2, temp not high

·      Pharmacological: anaesthetic, relaxant, anti-epileptic, osmotic

o  Hypertonic: 3mL/kg ≈ 200mL

o  Mannitol: 0.5mg/kg = 2.5mL/kg ≈ 200mL

·      Surgical: EVD

 

SAH complications:

Early neuro

·      Seizures: Rx propofol, levetiracetam

·      Obstructive hydrocephalus: Rx EVD

Late neuro

·      Re-bleed

o  Esp 1-2 days

o  P/w headache, ↑ICP, ↓GCS

o  Often fatal

·      Vasospasm

o  Esp 3-15 days

o  P/w focal neuro deficit (stroke-like)

o  Prevention: HHH

o  Rx HHH, nimodipine, endovascular

Cardiovascular

·      Arrhythmia

·      Neurogenic APO

·      AMI

Metabolic

·      SIADH

·      CSW

 

If pregnant:

·         >32 -> deliver

·         24-32 -> deliver if foetal distress

·         <24 -> don’t deliver