Overview of Cerebral Infarction
A large cerebral infarction caused by occlusion of the main artery of the brain is characterized by headache, limb paralysis, loss of sensation, aphasia, and impaired consciousness, which are mostly caused by atherosclerosis, cardiac embolism, and insufficient cerebral perfusion, with intravenous thrombolytic and surgical treatments during the acute phase, and rehabilitation during the recovery phase.
Definition
Massive cerebral infarction generally refers to a large area of cerebral infarction formed by occlusion of the main cerebral artery, which has a high rate of disability and death.
There are various definitions of “large area”, and one commonly used clinical criterion is that the volume of the lesion is more than 50 ml, and there is extensive cerebral ischemia (ASPECT score <6) as determined by cranial CT, and the ischemia area involves more than one lobe of the brain.
The ASPECT score (Alberta Stroke Program Early CT Score) is a method used by clinicians to evaluate the extent of cerebral ischemia.
Incidence
The annual incidence of large cerebral infarction in China is 10-20/100,000 people, accounting for 10% of ischemic strokes.
It accounts for 2% to 8% of cerebral hemisphere cerebral infarction cases and 4% to 25% of cerebellar infarction cases.
Causes
Causes
Atherosclerosis
Atherosclerosis is the main and most common cause of the disease.
Due to abnormal lipid metabolism, lipid deposits on the inner wall of the arterial vessels lead to atherosclerosis, which forms plaques and narrows the blood vessels.
Atherosclerotic lesions lead to the destruction of the wall structure and the development of entrapment or hematoma in the arteries, resulting in occlusion or narrowing of the blood vessels.
If blood supply is not compensated from other sources, ischemia of brain tissue will result.
Cardiogenic embolism
Various emboli from other parts of the body enter the main arteries of the brain along with the blood flow, causing acute occlusion or severe narrowing of the blood vessels, leading to ischemia, hypoxia, and necrosis of the brain tissue.
Common causes include atrial fibrillation, rheumatic heart disease, acute myocardial infarction, left ventricular thrombus, congestive heart failure, and dilated cardiomyopathy.
Inadequate cerebral perfusion
A sudden drop in blood pressure on the basis of severe narrowing of large blood vessels in the brain leads to localized hypoperfusion of brain tissue, resulting in ischemia and necrosis.
High risk factors
The presence of the following conditions is a high-risk factor for this disease.
Advanced age.
Hypertension, hyperlipidemia, diabetes mellitus, hyperhomocysteinemia (metabolic syndrome).
Family history of stroke.
Chronic smoking and alcohol consumption.
Obesity, overweight, chronic physical inactivity.
People with heart diseases such as atrial fibrillation, rheumatic heart disease, coronary atherosclerotic heart disease (coronary heart disease).
Pathogenesis
Occlusion or blockage of the main arteries supplying blood and oxygen to the brain, such as the internal carotid artery, middle cerebral artery, and vertebral-basilar artery, can lead to extensive brain tissue damage.
If there is no timely recovery within a short period of time, brain tissue necrosis and neurological dysfunction will occur.
Different parts of the infarction affect different neurological functions, and multiple manifestations can occur at the same time.
Symptoms
Main Symptoms
Movement disorders
Weakening of facial and limb strength, and activity inconvenience, such as crooked mouth, inability to lift objects, lifting effort or inability to lift, and shuffling in walking.
Complete paralysis of the limbs and inability to move can also occur.
Sensory impairment
Sensory loss or loss of sensation in the limbs, with loss of sensitivity to pain and hot and cold stimuli being the most prominent.
It may be accompanied by numbness, pain, burning sensation and pins and needles sensation.
Disorders of consciousness
It can be manifested as different degrees of consciousness disorder.
Drowsiness: fall asleep automatically from time to time, but can be awakened, wake up with normal consciousness, and continue to fall asleep after stopping the stimulation.
Somnolence: appears to be in a deeper state of sleep and is more difficult to awaken.
Delirium: disorganized behavior and inability to concentrate.
Coma: Appears to be in a sleep state, unable to move on his/her own, unresponsive to external stimuli such as pain or sound.
Aphasia.
Mainly the ability to speak, understand and express oneself is affected.
Motor aphasia: the ability to understand what is said, but the inability to express oneself.
Sensory aphasia: There is no language expression disorder, but there is a disorder in understanding language, which is manifested by not only not understanding what others say, but also not knowing what they are saying.
Naming aphasia: This is characterized by being able to say what an object is used for when you see it, but not being able to name it.
Dysarthria and dysphagia
Difficulty in vocalization, slurred speech, etc.
Difficulty in eating, choking while drinking, and even inability to eat in severe cases.
Cognitive impairment
Memory loss, inability to concentrate, inability to calculate.
Decreased ability to learn new knowledge and master new skills, or even dementia.
Autonomic dysfunction
Poor and laborious urination and defecation.
Inability to control urination and defecation and to pass out on your own.
Other symptoms
Symptoms of hypothalamic damage
Massive urination, irritability, extreme thirst, drowsiness.
Centralized hyperthermia, increased blood sugar, vomiting blood, black stools.
Symptoms of cerebral nerve damage
Ptosis, downward and outward strabismus of the eyeballs, inability to rotate flexibly, double vision.
Ptosis of the corners of the mouth, gill leakage, shallow nasolabial folds.
Hearing loss, tinnitus, vertigo.
Darkening of the eyes, blurred vision, visual defects.
Non-specific symptoms
Headache, dizziness, nausea, vomiting, photophobia.
Complications
Cerebral edema, brain herniation
The most common complication, swelling of the infarct site and surrounding brain tissue, increased brain size.
Early symptoms are nausea, vomiting, drowsiness or unresponsiveness.
In severe cases, irregular or sudden respiration and coma may occur.
Hemorrhagic transformation
Hemorrhage resulting from the restoration of blood flow to the vessels in the ischemic area after acute infarction.
It manifests as aggravation of the original limb paralysis, impaired consciousness and other symptoms.
Digestive tract bleeding
Injury, bleeding and ulceration of the digestive tract mucosa caused by stress reaction and the use of antiplatelet aggregating drugs.
The symptoms include black tarry stools and vomiting of coffee-colored liquid.
Secondary Epilepsy
Damage to brain tissue results in sudden abnormal discharges of nerve cells, which may lead to epilepsy.
This may manifest as generalized convulsions, apnea, cyanosis of the face and lips, and foaming at the mouth.
Infection
Lung, urinary tract, and skin infections can occur due to prolonged bed rest due to paralysis, swallowing disorders, aspiration, weakness in coughing up sputum, poor urination, and inadequate cleaning.
Symptoms such as fever, cough, sputum, cloudy urine, rash, pustules, etc. are manifested.
Lower extremity deep vein thrombosis/pulmonary embolism
Lower extremity venous thrombosis can be caused by limb paralysis and prolonged bed rest.
It is characterized by swelling of the limb, slightly high local skin temperature, and in severe cases, distal necrosis of the limb.
Dislodgment of thrombus may cause pulmonary embolism, resulting in life-threatening respiratory distress, cyanosis, coughing and hemoptysis.
Consultation
Department of Medicine
Neurology
If symptoms such as limb weakness, numbness, and unfavorable speech occur, it is recommended to consult a doctor promptly.
Emergency Department
If you experience symptoms such as unconsciousness, seizures, or difficulty breathing, it is recommended that you consult the Emergency Department or call the 120 emergency number as soon as possible.
Preparation for medical treatment
Preparation for medical consultation: registration, preparation of documents, common problems
Tips for seeking medical treatment
Try to keep a record of symptoms, duration, etc., so that you can give your doctor more information.
If you have the habit of monitoring and recording your blood pressure and blood glucose every day, you can provide the records to the doctor.
Patients with mobility problems and rapidly changing conditions should be accompanied by their family members, and avoid driving or riding to the doctor on your own.
Preparation List
Symptom list
Pay special attention to the time of onset of symptoms, special performance, etc.
Any headache, dizziness, nausea or vomiting?
Are there any weakness or numbness in the limbs?
Are there any speech problems, confusion?
Any choking on water, slurred speech, etc.?
Medical History Checklist
Has anyone in the family suffered from cerebrovascular disease, such as cerebral infarction, cerebral hemorrhage?
Is there hypertension, hyperlipidemia, diabetes mellitus, heart disease?
Is there any high salt, high sugar, high fat diet, obesity, lack of exercise?
Any history of long-term smoking or alcohol consumption?
Checklist
Test results of the last six months, which can be brought to the doctor’s office
Laboratory tests: complete set of blood biochemistry, liver and kidney function, coagulation test.
Imaging tests: cranial CT, cranial MRI
Other tests: transcranial Doppler ultrasound, angiography, electrocardiogram, etc.
Medication list
Medications used in the last 3 months, if available in boxes or packages, carry them to the doctor’s office
Blood pressure-lowering drugs: nifedipine, captopril, verapamil.
Blood sugar-lowering drugs: metformin, insulin, glibenclamide.
Lipid regulators: Atorvastatin, Simvastatin, Probucol, Benzafibrate.
Antiplatelet aggregating drugs: aspirin, tegretol, clopidogrel.
Anticoagulants: warfarin, rivaroxaban.
Diagnosis
Diagnosis is based on
Medical history
Family history of cerebrovascular disease.
There are underlying diseases such as hypertension, hyperlipidemia, diabetes mellitus, and heart disease.
Have high salt, high sugar, high fat diet, obesity, lack of exercise.
There is a history of long-term smoking or alcohol consumption.
Clinical manifestations
Manifestations include headache, vomiting, limb weakness, decreased sensation, speech and swallowing disorders, and impaired consciousness.
Laboratory Tests
Main items: blood glucose, blood lipids, homocysteine, coagulation, etc.
Purpose of examination: To detect the presence of underlying diseases, causes of disease, and overall physical condition.
Precautions: Some items require fasting and regular review.
Imaging
Transcranial Doppler ultrasound (TCD) and carotid ultrasonography
To detect stenosis and occlusion of large arteries, assess collateral circulation and monitor microemboli, and assess the condition of cerebral blood circulation.
It can show atherosclerotic plaques, stenosis and occlusion of blood vessels.
Ultrasound is economical, convenient, non-invasive and repeatable, but accuracy is greatly affected by the experience of the operator.
Cranial Magnetic Resonance Imaging (MRI) and Angiography (MRA)
MRI can detect ischemia and infarction in various regions of the brain and is particularly suitable for the acute stage, showing the lesion area within hours of onset.
MRA can dynamically show the direction of blood flow and is more intuitive for the display of collateral circulation.
Precautions:
MRA results may put the degree of stenosis in the aorta.
Those who have metal implants such as dentures or cardiac stents in the body need to inform the radiologist to determine whether an MRI can be performed based on the specific MRI machine.
Head and Neck Computed Tomography (CT) and Angiography (CTA)
Plain CT quickly distinguishes between cerebral infarction and cerebral hemorrhage.
CTA can show the size, shape, blood flow, wall and other characteristics of blood vessel lumen, and also clearly observe the relationship between blood vessels and surrounding tissues.
Precautions:
CT/CTA examination has a certain degree of radioactivity and should not be used by children or pregnant women.
CTA examination requires the use of contrast medium, and should not be used by patients with abnormal renal function.
Digital Subtraction Angiography (DSA)
Digital subtraction angiography (DSA) can accurately and intuitively determine the degree, location, shape and scope of stenosis of blood vessels.
It is an invasive examination and is usually accompanied by endovascular intervention.
Precautions:
Do not eat or drink for 6 hours before the examination.
If you take metformin orally before the examination, you need to stop taking it for 48 hours.
An iodine allergy test is required before the examination to prevent allergy to the contrast agent.
Keep the skin at the examination site clean and clear.
Other Tests
Electrocardiogram (ECG): to understand the status of blood supply to the heart and cardiac function.
Electroencephalogram: mainly used to diagnose secondary epilepsy.
Differential Diagnosis
Cerebral hemorrhage
Similarities: both have headache, vomiting, consciousness disorder and other manifestations.
Differences: The onset of cerebral hemorrhage is more rapid, with symptoms reaching a peak within minutes or hours; impaired consciousness is common and more severe; high-density foci in the brain parenchyma on CT examination; cerebrospinal fluid may be bloody; and increased blood pressure is obvious.
Intracranial space-occupying lesions
Similarity: headache, dizziness, weakness of one side of the limbs and other symptoms.
Differences: intracranial space-occupying lesions are common in brain tumors and cysts, which may have acute attacks but tend to develop chronically and progressively.
Subarachnoid hemorrhage
Similarity: nausea, vomiting, headache and other symptoms.
Difference: subarachnoid hemorrhage has severe headache, but the focal neurological disorders such as limb weakness, numbness and aphasia are not obvious. Head CT can clearly diagnose the amount and location of bleeding.
Treatment
Therapeutic purpose: save the ischemic semidarkness band, reduce the primary brain damage, avoid serious complications.
Treatment principle: Intravenous thrombolysis and surgery are the mainstay of treatment in the acute stage, and drugs and rehabilitation are the mainstay of treatment in the recovery stage.
General treatment
Bed rest, cardiac monitoring, close monitoring of consciousness, pupil, pulse, respiration and blood pressure changes.
When coma and respiratory difficulty occur, timely oxygen intake, tracheal intubation and ventilator-assisted ventilation can be performed.
Suspend eating and drinking if vomiting.
Nutritional support can be provided through nasal feeding tube or intravenous fluid route when there is swallowing disorder.
Avoid forceful defecation and coughing, when defecation is laborious, laxatives can be given to evacuate the stool.
Keep the skin clean, turn over regularly, and use air cushion or soft cushion to prevent pressure ulcers.
Use long compression stockings and pneumatic compression devices to prevent deep vein thrombosis of the lower limbs.
When fever occurs, physical cooling can be supplemented by placing ice packs in the groin, armpits and neck, and cooling beds or cold mattresses can also be used.
Medication
Intravenous thrombolysis
Purpose of medication: Intravenous thrombolysis is currently the most important measure to restore blood flow.
Common drugs are alteplase (rt-PA).
Precautions:
Requires short onset and still in the thrombolytic time window (within 4.5 hours of onset).
Common risk is intracranial hemorrhage, with a higher chance of cerebral hemorrhage from cardiogenic embolism.
Excessive infarct size and multilobar infarcts are contraindications to intravenous thrombolysis.
Antiplatelet aggregation therapy
Purpose of medication: to prevent new thrombus formation, to prevent intravascular thrombus proliferation and expansion, and to reduce the risk of recurrence.
Commonly used drugs: aspirin, clopidogrel.
Precautions:
Patients in the acute phase who fail thrombolytic therapy should take aspirin (150 to 325 mg/d) as early as possible within 48 hours.
Aspirin can have side effects such as gastrointestinal bleeding and allergy, in which case clopidogrel can be used instead.
Neuroprotective therapy
Purpose of medication: improve cerebral microcirculation, reduce brain damage.
Commonly used drugs: butylphthalide, edaravone and so on.
Precautions:
Pay attention to monitoring heart rate, liver and kidney function.
Severe renal failure is contraindicated.
Lipid-lowering drugs
Therapeutic purpose: regulate blood lipids, stabilize atherosclerotic plaques and reduce the risk of plaque detachment.
Commonly used drugs: statins (Rosuvastatin, lovastatin, etc.), nicotinic acid drugs (niacin, acyclovir, etc.), fibrates (fenofibrate, benzafibrate, etc.).
Precautions: Abnormal liver function, constipation, abdominal pain, myalgia, hot flashes and itching of the skin may occur.
Other medications
Control blood pressure: Labetalol, nicardipine, nifedipine and other drugs can be used to control blood pressure when it is too high.
Control blood sugar: insulin treatment is commonly used, and blood sugar monitoring is strengthened at the same time.
Reduce intracranial pressure and cerebral edema: use mannitol, glycerol fructose, furosemide, etc. to reduce intracranial pressure.
Anti-infection treatment: choose sensitive antibiotics, such as cefuroxime, ceftriaxone and so on.
Preventing venous thrombosis: low molecular heparin or heparin preparation can be injected subcutaneously.
Surgery
Purpose of surgery: to reverse the occupying effect, reduce the displacement of brain tissues, lower the intracranial pressure and improve the cerebral perfusion pressure, so as to prevent further brain damage.
Indications: patients with severe cerebral edema, elevated intracranial pressure and brain herniation.
Commonly used procedures: debridement decompression, hemodynamic reconstruction, internal decompression.
Precautions:
Hematoma removal can be performed at the same time when there is hemorrhagic transformation.
Postoperative care is needed to prevent complications such as wound infection and intracranial hematoma.
Intervention
Purpose of the procedure: to reduce/remove the obstruction of blood flow by the embolus and increase blood flow to the brain.
Indications: anterior circulation large vessel occlusion <6h, posterior circulation large vessel occlusion <24h.
Commonly used procedures: arterial thrombolysis, mechanical thrombolysis, angioplasty and stenting.
Precautions: endovascular treatment is contraindicated in case of intracranial hemorrhage, large infarct area, and multilobar infarction.
Sub-low temperature treatment
Therapeutic purpose: reduce the oxygen consumption of brain tissue through temperature control, reduce cerebral edema, protect cerebral nerve cells and reduce intracranial pressure.
Commonly used methods: Isoprinosine, chlorpromazine, need to cooperate with ice blanket, ice cap.
Precautions:
Light hypothermia is the mainstay, usually not below 35 degrees Celsius.
Avoid hypothermia leading to other organ complications.
Rehabilitation
Treatment principle: After the condition is stabilized, an individualized rehabilitation program is formulated according to the dysfunction that occurs.
Exercise therapy
Limb function training
Passive training: move the upper and lower limbs with the assistance of the therapist during the period of bed rest, to the extent that it can be tolerated, which can prevent muscle atrophy, avoid muscle tension and stiffness, and maintain the range of motion of the joints.
Active training: under the guidance of the therapist, turn over, get up, keep sitting, stand up, walk training.
Pay attention to safety and moderate labor and leisure during training to prevent postural abnormality and avoid fall, over-fatigue and aggravation of the condition.
Sensory function training
Superficial sensory training: focusing on tactile stimulation of the skin, such as pain, touch, alternating temperature stimulation of ice and warm water, touching and recognizing daily necessities.
Deep sensory training: Sensory training should be combined with motor training, such as squeezing and weight bearing on the joints during training, to obtain the correct motor experience in the process of completing the movement.
Respiratory function training
Deep breathing, balloon blowing, coughing and abdominal breathing.
Elevate the head of the bed 30°～45° during the training to avoid vomiting and aspiration.
Swallowing function training
Swallowing disorders can be relieved by changing the eating posture and adjusting the character of food.
Improve the strength of swallowing muscles by swallowing without food and small amount of food.
Improve the sensory function of swallowing muscles through stimulation methods such as ice-cold cotton wool sticks and tactile sensation.
Speech and phonological function training
Improve speech by training patients to respond correctly in listening, speaking, reading and writing.
Train the facial and throat muscles to improve the clarity and fluency of articulation.
Cognitive function training
Adopt “one-to-one” or multi-person group training.
Memory, calculation and thinking skills are trained through memorization of numbers, math problems, and reasoning problems.
Daily life ability training
Improve the patient’s ability to live independently and reduce the burden on the caregiver.
Practical daily living activities such as dressing, getting up, eating, washing, and handling urine and feces are practiced.
Physical factor therapy (physiotherapy)
Restore muscle strength and motor function through biofeedback and neuromuscular electrical stimulation therapy.
Traditional Chinese Medicine (TCM)
It is often based on the principles of clearing heat and removing blood stasis, detoxifying the channels, removing phlegm and clearing the bowels, and waking up the brain and opening up the mind.
Commonly used prescriptions: Phlegm elimination soup, antelope horn soup with additions and subtractions, antelope horn and hook vine soup, tianma and hook vine drink with additions and subtractions, Dachengqi soup, etc.
Commonly used proprietary Chinese medicines: Thrombotoxin, Angong Niuhuang Pill, Waking Brain Jing, Qingkailing, Tongxin Capsule, Niuhuang Qingxin Pill and so on.
In addition, acupuncture, moxibustion, tuina and other treatments can also be used.
Prognosis
Cure
The prognosis of massive cerebral infarction is extremely poor, and the death rate can be as high as 53% to 78%.
About 2/3 of the surviving patients are left with serious disabilities, such as long-term coma, aphasia and limb paralysis.
Hazards
Impaired consciousness may not improve over time, and some patients may enter a vegetative state (vegetative).
Paralysis of limbs, cognitive and speech disorders, incontinence, etc., seriously affect the patient’s quality of life.
Severe and irreversible disability may bring huge psychological disorder, cause mental illness, and increase the burden of family and society.
Daily Management
Daily Management
Dietary management
Balanced diet, choosing a variety of foods to achieve reasonable nutrition, in order to ensure adequate nutrition and appropriate weight.
Use less-salt and less-oil cooking methods, such as steaming, boiling, mixing, water-skimming, simmering, etc., for easy digestion and absorption.
Eat more vegetables, fruits and whole grains. Vegetables can be cooked in less time or cold.
Avoid foods that contain a lot of salt, such as salted meat, salted vegetables and other foods.
Avoid spicy and stimulating foods, such as chili peppers, coffee and strong tea.
For those who have difficulty in swallowing, eat pureed or pasty food.
Quit smoking and drinking.
Life management
Appropriate exercise can be done under the guidance of physician after the disease is stabilized.
Blood pressure, blood sugar, blood lipid and other indicators should be strictly controlled to reach the ideal range.
Avoid exertion and take rest.
Avoid fluctuation of blood pressure due to excessive emotional fluctuation, which may aggravate cerebral ischemia.
Psychological support
Patients themselves try to minimize anxiety, maintain a stable, positive and optimistic mental state, and establish confidence in overcoming the disease, which will be helpful to the recovery of the disease.
Family members should care more about the patient and increase communication and exchange with the patient.
If necessary, seek help from professional psychological practitioners.
Disease monitoring
Monitor changes in symptoms such as state of consciousness, muscle weakness and sensory loss on a daily basis.
Monitor and control blood pressure, blood lipids and blood sugar.
Gastrointestinal bleeding may occur during treatment and should be observed for abdominal pain and dark stools.
Follow-up review
Follow the doctor’s instructions for regular review, generally 1 to 3 months need to review, in order to adjust the treatment program.
The main review items include blood lipid, blood sugar, homocysteine, etc., transcranial Doppler ultrasound and cranial MRI.
Prevention
For those who have not developed the disease
Control the underlying disease to avoid massive cerebral infarction.
Actively treat underlying diseases such as hypertension, hyperlipidemia, diabetes mellitus, heart disease, hyperhomocysteinemia.
Abstain from smoking and alcohol, regularize work and rest, and ensure sleep.
Diversify daily diets and pay attention to low salt, low fat and sugar control.
Obese and overweight people should lose weight.
Exercise aerobically for 30 to 45 minutes a day, five days a week, such as walking, jogging and bicycling.
Be alert to the onset of aura, such as sudden numbness on one side of the face or upper and lower limbs, weakness, crooked mouth, vertigo, etc.
For those who have already developed the disease
On the basis of the above preventive measures, avoid recurrence through medication, surgery and other methods.
Commonly used drugs: aspirin, clopidogrel, atorvastatin, warfarin, etc.
Surgical interventions: angioplasty, stenting, carotid endarterectomy, etc.