This document provides an overview of subarachnoid hemorrhage (SAH). It defines SAH as blood entering the subarachnoid space, with the most common cause being the rupture of an intracranial aneurysm (65-80% of cases). The incidence is about 9-10 per 100,000 people per year. Clinical presentation includes a sudden, severe headache and may include decreased consciousness, neck stiffness, vomiting, and vision changes. Diagnosis is made through CT scan, MRI, lumbar puncture, and angiography. Multiple grading scales exist to classify SAH severity and predict outcomes, with the Hunt and Hess and World Federation of Neurosurgeons scales discussed in detail.

1. SUBARACHNOID
HAEMORRHAGE (SAH)
DR. MAUSAMINBEN HATHIDARA

2. INTRODUCTION
 Subarachnoid hemorrhage (SAH) is a pathologic condition
that exists when blood enters the subarachnoid space
 The most common cause of SAH is trauma
 The most common cause of spontaneous SAH is an
aneurysmal bleed (65-80%)

4. EPIDEMIOLOGY
Incidence about 9-10/100,000/yr
Higher in Japan (3 times) and Finland
Mean age of onset 51 years (6th
decade)
Facts and figures
 Men predominate until age 40, then moreMen predominate until age 40, then more
women (55%); some studies – 3:2 ratiowomen (55%); some studies – 3:2 ratio
 Seasonal (winter/spring), diurnal (late morning)Seasonal (winter/spring), diurnal (late morning)
and day (Sunday)and day (Sunday)
 30 % rupture during sleep30 % rupture during sleep
 About 50 % of patients with an aneurysm haveAbout 50 % of patients with an aneurysm have
warning prior to SAH (6-20 days)warning prior to SAH (6-20 days)

5. Case Fatality
The Overall case fatality varied from 32-67%
Population-based study in England with essentially
complete case ascertainment
 24 hour mortality: 21%24 hour mortality: 21%
 7 days: 37%7 days: 37%
 30 days: 44%30 days: 44%
Pobereskin JNNP 2001;70:340-3

6. ETIOLOGY
CATEGORY CAUSES
TRAUMA CLOSED, PENETRATING, ELECTRIC,ETC…
VASCULAR ANEURYSMS, ATHEROSCLEROSIS, AVM, VASCULITIDES
IDIOPATHIC BENIGN PERIMESENCEPHAIC SUBARACHNOID
HEMORRHAGE
BLOOD DYSCRASIAS LEUKEMIAS, HEMOPHILIAS, THROMBOCYTOPENIAS
INFECTIONS DENGUE, LEPTOSPIROSIS, BACTERIAL MENINGITIS
TOXINS AMPHETAMINES, COCAINE, NICOTINE,
ANTICOAGULANTS
NEOPLASMS GLIOMAS, MENINGIOMAS, HEMANGIOBLASTOMA, ETC

7. Risk Factors
 HypertensionHypertension
 Cigarette smokingCigarette smoking
 Oral contraceptivesOral contraceptives
 Alcohol consumption (debatable)Alcohol consumption (debatable)
 Diurnal variations in blood pressureDiurnal variations in blood pressure
 Pregnancy and parturitionPregnancy and parturition
 Slight increased risk during lumbar punctureSlight increased risk during lumbar puncture
and/or cerebral angiography in patient withand/or cerebral angiography in patient with
cerebral aneurysmcerebral aneurysm
 Slight increased risk with advancing ageSlight increased risk with advancing age
 Following cocaine abuseFollowing cocaine abuse

8. PATHOPHYSIOLOGY
CEREBRAL BLOOD
FLOW AND
METABOLISM
RAISED ICT
IMPAIRED
VASODILATORY
AUTOREGULATION
VASOSPASM WITH
GLOBAL ISCHEMIA
BLOOD (‘TOXIC’)
BLOCKAGE OF THE
ARACHNOID
GRANULATIONS
SYMPATHETIC
SURGE
MI
PULMONARY
EDEMA

9.  CEREBRAL BLOOD FLOW/VOLUME/METABOLISM
CBF is globally decreased after SAH
Mean CBF decreases with time after SAH; it reaches a nadir in
10 to 14 days, after which it slowly increases toward normal,
In patients with poor grades, CBF and cerebral metabolism
may remain depressed for weeks ;
Cerebral blood volume was markedly increased in patients
with severe neurological deficits

10.  INTRACRANIAL PRESSURE RESPONSES
Mean ICP was 10 mm Hg in patients with clinical grades 1 and
2, 18 mm Hg in patients with clinical grades 2 and 3, and
29 mm Hg in those with clinical grades 3 to 5.
Vasospasm, which was more common in patients with a poor
clinical grade and larger SAH, was associated with a
significant rise in ICP from a mean of 16 mm Hg in those
without vasospasm to 29 mm Hg in those with vasospasm

11. PRESENTATION
 HEADACHE :
The most common symptom (97%)
Usually severe ("the worst headache of my life) and sudden in
onset.
They may clear and the patient may not seek medical attention
(sentinel/warning bleeds) - in 30-60% of cases
Vomiting may be present
May pulsate towards the occiput and may sometimes be
percieved as neck pain

12.  OTHER SYMPTOMS
Decreased consciousness and alertness
Eye discomfort in bright light (photophobia)
Mood and personality changes, including confusion and irritability
Muscle aches (especially neck pain and shoulder pain)
Nausea and vomiting
Numbness in part of the body
Seizure (1 in 14)
Stiff neck
Vision problems, including double vision, blind spots, or temporary
vision loss in one eye

13.  SIGNS
MENINGISM (neck stiffness, kernigs and brudzinskis)
Hypertension
Focal neurological deficit
Ocular signs
Coma

15. INVESTIGATIONS
 CT Scan
 MRI
 Lumbar Puncture
 Angiography

16. GRADING
GRADE SIGNS/SYMPTOMS SURVIVAL
1 Asymptomatic/Minimal headache
or neck stiffness
70%
2 Moderate/severe headache with
neck stiffness +/- CN palsies
60%
3 Drowsy/ minimal neurological
deficit
50%
4 Stuporous with hemeparesis 20%
5 Comatose with decereberate
posturing/response
10%
0 Unruptured aneurysm -
1a No Meningism but with fixed
neurodificit
-
HUNT AND HESS IN 1968

17. GRADE CT APPEARANCE
1 NONE
2 < 1mm thickness
3 > 1mm thickness
4 Diffuse with
parenchymal/ventricular extension
FISHERS
GRADE CT APPEARANCE
0 NONE
1 MINIMAL
2 MINIMAL WITH IVH
3 THICK
4 THICK WITH IVH
CLAASSENS MODIFICATION

18. GRADE GCS NEURODEFICIT
1 15 ABSENT
2 13-14 ABSENT
3 13-14 PRESENT
4 7-12 ABSENT/PRESENT
5 <7 ABSENT/PRESENT
WORLD FEDERATION OF NEUROSURGEONS (WFNS)

19. GRADE CLINICAL PRESENTATION
1 CONSCIOUS
2 DROWSY
3 DROWSY WITH DEFICIT
4 MAJOR NEURODEFICIT
5 MORIBUND
BOTTERELL ET AL

20.  A newer grading by Ogilvy and Carter - to predict outcome
and gauge therapy
 The system consists of five grades and it assigns one point
for the presence or absence of each of five factors:
Age greater than 50
Hunt and Hess grade 4 or 5;
Fisher scale 3 or 4
Aneurysm size greater than 10 mm
Posterior circulation aneurysm 25 mm or more

21. THANK YOU