Subarachnoid hemorrhage

600px|right|Mozkové pleny In subarachnoid hemorrhage (SAH), blood leaks into the cerebrospinal fluid pathways between the arachnoid and the pia mater. This is massive bleeding from the arterial basin.

Causes
thumb|right|Willisův okruh It most often occurs when an aneurysm ruptures (60%), in the area of ​​the circle of Willis, especially on the anterior or posterior communicating artery, often when blood pressure increases (physical exertion, coitus, irritation, defecation, etc.). Another cause can be trauma, vascular malformations such as arteriovenous and cavernous malformations, anticoagulant therapy , bleeding diseases , hypertension , amyloid angiopathy , primary vasculopathy. There are also idiopathic (cryptogenic) SACs. Traumatic SAK are often associated with contusion.

Symptoms
The headache comes on within seconds and can be very intense. It is localized bilaterally, sometimes with a maximum occipitally. Initially, there may be a short disturbance of consciousness. The pain is also accompanied by nausea, vomiting , photophobia and phonophobia. Meningeal syndrome continues to develop over minutes to hours. Patients are often disoriented, confused, some patients are somnolent to the point of sopor, sometimes, on the contrary, psychomotor restlessness, aggressiveness, negativism can dominate. Focal symptoms develop during intracerebral propagation of SAK. We assess the patient's condition using the scale according to Hunt and Hess - seevascular disease of the brain. In some cases, the symptoms may be less intense and mimic cervicocranial syndrome, so in unclear cases we always indicate brain CT and LP .

Diagnostics
thumb|Schéma SAK na CT thumb|SAK na CT We establish the diagnosis with a CT scan. About 5% of CT examinations in the first 24 hours do not show SAH, so if SAH is suspected, we indicate a cerebrospinal fluid examination. A typical cerebrospinal fluid finding is the finding of oxyhemoglobin during spectrophotometric examination. '''Liquor must be processed within 1 hour after collection. We also find increased protein and in the cytological examination thousands to hundreds of thousands of erythrocytes, from the 3rd to the 4th. day of erythrocyte phagocytosis and maximum bilirubin during spectrophotometry .'''

Treatment
If SAH is proven, we send the patient to neurosurgery for cerebral panangiography, which should be performed within 72 hours of the onset of symptoms due to the risk of vasospasm. When an aneurysm is found and the score according to H+H is up to 3, surgery is indicated - either clipping the aneurysm neck or filling the aneurysm cavity with a detachable spiral - coiling. Bed rest ( always hospitalization ), symptomatic treatment ( analgesics, antiemetics , correction of hypertension ) is essential. Vasospasms can be dampened by calcium ion blockers.

If an aneurysm is not detected, the patient is treated conservatively - painkillers, mucolytics and laxatives, and after 3-6 weeks a control panangiography is indicated.

Aneurysm bleeding
An aneurysm is a circumscribed enlargement of a cerebral artery. The bulge is caused by the long-term effect of blood pressure on a weakened vessel wall (congenital defects, atherosclerosis, fungal infections, trauma, etc.). Arching thins the vessel wall, which bursts with a sudden increase in blood pressure (exertion, defecation, coitus, upset, bending forward). Aneurysms are most often found in the area of ​​the circle of Willis, especially on the internal carotid artery , a. communicans ant., a. cerebri media ).

Bleeding from cerebral aneurysm is relatively common in the Czech Republic (about 600 cases of SAH per year), unfortunately with a very high mortality rate (40% of patients die after the first bleeding). Aneurysms themselves (especially smaller ones) are clinically silent until they rupture and bleed.

Symptoms
Manifestations are sudden, dramatic and rapidly progressive. The initial symptom is an intense headache (severe, not yet recognized), followed by nausea , vomiting , increased systemic pressure due to Cushing's reflex, photophobia, impaired consciousness , focal neurological findings depending on the location of the aneurysm, epileptic seizures may also be present. meningismus, elevated temperature, may also be present. lesions of the cranial nerves ( III and VI ), etc.

Diagnosis
To establish the diagnosis of SAH, it is necessary to perform a CT scan (evidence of blood in the cerebrospinal fluid spaces, intracerebral hematoma), which can even approximately outline the source of the bleeding. He will subsequently refine the cerebral panangiography, which we try to perform as soon as possible after the diagnosis of SAK, and always in at least two projections. In patients without intracranial hypertension, in whom the CT scan was not sufficiently conclusive, we collect and examine CSF (proof of the presence of erythrocytes or xanthochromin).

The therapeutic procedure is based on the classification according to Hunt and Hess.


 * grade 0 – non-bleeding aneurysm, without symptoms,
 * grade I – headache, neck opposition, mild meningeal syndrome,
 * grade II – headache, neck opposition, lesions cranial nerve lesions, more pronounced meningeal syndrome,
 * grade III – attenuation or confusion, slight bearing finding,
 * degree IV – stupor, decerebrate rigidity , vegetative disorders ,
 * grade V – deep coma, decerebrate rigidity

Arteriovenous malformations
An AV malformation (AVM) is a congenital convolution of arteries and veins that directly communicate with each other and between which a capillary system has not been formed. As a result of the defect, capillary resistance is negligible, which results in increased blood flow in the malformed vessels. At the expense of this, other areas have less blood supply and are subject to ischemia ( steal phenomenon ).

Clinically, it is manifested by bleeding (70%), not only SAH, but also intracerebral. Ischemia of less blood-supplied parts leads to localized manifestations (e.g. epileptic seizures).

For basic diagnosis, we use CT and MRI, then we clarify the source of the bleeding using PAG.

Therapy
Malformations tend to be extensive and often difficult to access surgically. If these are not very acute cases, we choose the "watch and scan" method method, during which we evaluate the condition of individual vessels and their progression over time. Subsequently, we perform the procedure on arteries that could be at risk.

The operation consists in closing the supply arteries by bipolar coagulation (the performance takes many hours and is difficult). An alternative is embolization of arteries endovascularly, or the use of Leksell's gamma knife.

Cavernous hemangioma
This is a special type of AVM. A cavernoma is a circumscribed, small vascular formation in brain tissue that does not have wide supply arteries. For that reason, it is not usually visible on the PAG, so we prefer MRI for diagnosis.

Bleeding is not extensive, but rather frequent.

Differential diagnosis

 * Subdural hemorrhage
 * Epidural bleeding
 * Migraine
 * Acute cervicocranial syndrome
 * Meningitis

Related articles

 * Treatment of intracranial aneurysm
 * Article for graduate students
 * Craniocerebral trauma
 * Brain vessels
 * Stroke
 * Circle of Willis
 * Aneurysm
 * Arteriovenous malformation
 * Cavernous malformation