39. What are the functions of the nervous system? How is the nervous system classified?
The nervous system is a complex collection of nerves and neurons. It transmits signals, which let the parts of the body communicate. The nervous system is divided into the CNS and PNS. The CNS includes the brain and spinal cord. It provides higher mental functions, such as thinking, memory, behavior, speech, mood, and also controls our reflexes. The PNS includes nerves and ganglia. It is responsible for transmission of signals from the CNS to the other parts of the body.
40. What brain diseases do you know? Define them.
The human brain is susceptible to degenerative disorders, such as Parkinson’s disease, multiple sclerosis and dementia. Parkinson’s disease is characterized by slow degeneration of the central brain areas, causing problems with movement and coordination. Multiple sclerosis is a disorder in which myelin sheath (cover) is damaged. Dementia is a decline in cognitive function resulting from death of nerve cells in the brain. The most common form of dementia is Alzheimer’s disease.
Another brain disorders are: stroke – that is an interruption of blood supply of the brain; cerebral edema – swelling of the brain tissue; hydrocephalus – an abnormally increased amount of cerebrospinal fluid inside the skull; brain tumour – abnormal tissue growth inside the brain; meningitis – is an inflammation of the brain caused by infection.
A number of psychiatric conditions, such as schizophrenia and depression, are caused by brain dysfunction, although the nature of such disorders is not well understood.
41. What is stroke? What are the types of brain stroke?
It is the acute interruption of the blood supply to the brain which may result in death of the brain cells.
There are two chief types of strokes: Ischemic stroke and Hemorrhagic stroke.
ISCHEMIC STROKE is the result of a blocked artery due to blood clot. This is the most common type of stroke and it is the cause of 90% of all strokes. This type of stroke can occur in 2 ways:
Thrombotic stroke - This occurs when the blood clot (thrombus) forms in an artery that supplies blood to your brain due to a blood vessel that is already narrow. The clot deprives a part of the brain of oxygen and blood causing the cells of that part of the brain to die.
Embolic stroke -This is also called cerebral embolism and it occurs when a blood clot or other debris breaks off (embolus) from a blood vessel away from your brain and travels through your bloodstream to lodge in narrower brain arteries.
HEMORRHAGIC STROKE - The second chief type of stroke occurs when a blood vessel in a part of the brain becomes weak and leaks or ruptures, causing blood to leak into the brain (Hemorrhage). Hypertension (high blood pressure) and aneurysms (weak spots in blood vessels) are the most common causes of brain hemorrhages. It may also be caused by the rupture of a defective blood vessel. There are two types of hemorrhagic stroke.
Intracerebral hemorrhage and Subarachnoid hemorrhage
43. What are the risk main causes of stroke?
Risk factors for having stroke, which can’t be controlled by an individual, are age, gender and genetics. Other risk factors can be controlled. They include: high blood pressure, high cholesterol level, diabetes, obesity, smoking, physical inactivity and stress. The main causes of stroke are atherosclerosis of brain arteries, embolism (or blood clot), ruptured aneurysm etc.
44. What do the symptoms and treatment of the brain stroke depend on? What are they?
Symptoms: Sudden numbness or weakness in the face, arm, or leg, especially on one side of the body, Sudden confusion, trouble speaking, or difficulty understanding speech. Sudden trouble seeing in one or both eyes. Sudden trouble walking, dizziness, loss of balance, or lack of coordination. Sudden severe headache with no known cause.
If you think someone may be having a stroke, act F.A.S.T. and do the following simple test:
F—Face: Ask the person to smile. Does one side of the face droop?
A—Arms: Ask the person to raise both arms. Does one arm drift downward?
S—Speech: Ask the person to repeat a simple phrase. Is their speech slurred or strange?
T—Time: If you observe any of these signs, call 113 immediately.
Treatment of a brain stroke depends on its type. The goal of the treatment
Ischemic stroke may be treated by medication to break up the clot causing the stroke. Tissue plasminogen activator is usually prescribed.
Anticoagulants are prescribed to prevent the development of blood clots.
Statins may be prescribed to reduce the level of cholesterol in blood.
Surgery may be necessary to remove the inner wall of the carotid artery (carotid endarterectomy).
Unlike the ischemic stroke, the treatment for hemorrhagic stroke doesn’t involve anticoagulants. Thinning the blood would increase the amount of blood being lost in the brain. In case of hemorrhagic stroke emergency surgery may be necessary to repair damaged arteries or reduce the pressure of the blood on the brain.
The patient may be given medication to help the brain’s blood flow return to normal.
As soon as patient is no longer acutely ill he or she must follow the rehabilitation therapy in order to regain his or her functional abilities.
45. What are the complications of the brain stroke? What do they depend on?
The complications of the brain stroke depend on the location of blood interruption. They include:
Swelling of the brain;
Accumulation of cerebrospinal fluid inside the skull (hydrocephalus);
Coma;
Paralysis or loss of muscle movement;
Memory loss;
Complications of stoke are related to the immobility of the patient.
The most common complications are bedsores, pneumonia, urinary tract infection, depression.
46. What therapy does rehabilitation of the patient after the stroke include?
Rehabilitation depends on the complications, which occur after the stroke. It includes:
Speech therapy – to regain ability to talk;
Occupational therapy – to regain dexterity in arms;
Physical therapy – to improve strength and walking.
-Psychological therapy.