We discussed in the article “What is a Stroke?” the two types of stroke – the first caused by occlusion of blood vessel by trombus and therefore disrupted blood flow (aka, ischemic stroke or cerebral infarct), and second – bleed caused by rupture of blood vessel inside the brain matter (aka, intracerebral haemorrhage, ICH). Moreover, stroke treatment for the two types differ profoundly.
Initially, both types of stroke appear very similarly. Symptoms include sudden weakness in the face and in one side of the body, difficulty speaking or understanding others. However, treatment for both types of stroke is radically different. Even more, treatment for one type of stroke can be life threatening if applied to another. Therefore, correct diagnosis prior to initiation of treatment is paramount.
Not to mention, most effective treatments in case of stroke are available only for a few hours after onset. Therefore, emergency medical attention is needed.
To differentiate one type of stroke from another, an emergency CT brain (computed tomography) scan with angiogram is performed as a routine diagnostic measure in most countries. This allows not only to distinguish between brain haemorrhage and brain infarct (ischaemia), but allows to detect the exact location of occlusion or rupture of blood vessel.
Once diagnosed, stroke treatment principles are as follows:
A key concept in case of blood vessel occlusion is restoration of blood flow as soon as possible. Since brain cells are very oxygen dependent, restoration of blood flow is proven to be effective only if applied within 4-6 hours from onset of disease. There are two main techniques used to restore blood flow:
- Intravenously administered medication that is meant to dissolve blood clot. This medication is called recombinant tissue plasminogen activator (tPA) — also known as alteplase. It is usually administered within 3 hours from symptom onset (sometimes within 4.5 hours). The sooner treatment is applied the lesser is damage to the brain and better results can be expected.
- Endovascular procedures. As you can understand from the title, these are procedures performed within the vessel. Artery in the groin is usually used to introduce the intravascular catheter which is then guided upwards into brain vessels under guidance of fluoroscopy. Once site of occlusion has been reached, doctors may use direct injection of alteplase through fine tubing to dissolve the clot or by using a specific device attached to the catheter and remove clot mechanically thereby restoring blood flow.
If the time frame allowed to use above mentioned techniques has passed, the key concept of treatment is limitation of so-called secondary brain damage. This is an expansion of cell death in areas around initial damage (called penumbra). Penumbra zone is partly supplied by blood from adjacent vascular territories. Improvement of blood flow in penumbra is achieved by various medications and i/v fluids.
Key concept of treatment of cerebral bleeding is to stop its expansion thereby minimizing pressure and damage to the brain. This can be achieved by medication aiming to lower high blood pressure and medication aiming to lower intracranial pressure (pressure inside the skull).
If a patient has previously used blood thinning medications, effects of these medications may be reversed by drugs of blood products that are antagonists to blood thinners.
If hemorrhage is initially large or is rapidly expanding, the patient’s condition is may be worsening. In this case, surgery may be performed as a life saving measure.
After emergency treatment is finished, the condition of the patient usually becomes stable in about 7 days. Then the next stage of treatment can be started. Lost function and regaining independence can be achieved through rehabilitation.