In the rescue of acute cerebral infarction, time is of the essence. What should we do if we miss the time window?

Among cerebrovascular diseases, cerebral infarction has a high incidence (accounting for 80% of all strokes) and a high disability rate. Many people asked Huazi, "I heard that brain cells have a low tolerance to hypoxia and will die after 6 minutes of ischemia. Moreover, once brain cells die, they cannot regenerate. So how should we rescue acute cerebral infarction?"

Huazi said that the death of brain cells is an irreversible process, but when cerebral infarction occurs, not all brain cells within the range of cerebral infarction die at the same time. As long as the blood vessels are reopened in time, a large number of brain cells can be rescued and the damage can be minimized.

1. Rescue brain cells in the ischemic penumbra area

The nerve cells in the brain are very sensitive to hypoxia and will die in 4 to 6 minutes under a state of complete hypoxia. When a cerebral infarction occurs, the cells in the core area of ​​the infarct lesion are the first to die, while the brain cells around the core area can rely on collateral circulation to obtain a small amount of blood supply, which will cause neurological dysfunction, but will not die completely. This part of the cells is called the ischemic penumbra.

As long as blood supply can be restored in time, brain cells in the ischemic penumbra can return to normal, but if the time is delayed too long, these cells will die completely and become infarction lesions. Saving cells in the ischemic penumbra is the top priority when acute cerebral infarction occurs.

2. The maximum time window for rescue is 6 hours

Intravenous thrombolysis or intravascular thrombectomy are both rescue methods for acute cerebral infarction. However, intravascular thrombectomy has high technical requirements and not all hospitals can perform it. At present, intravenous thrombolysis is the main rescue method for acute cerebral infarction.

Different thrombolytic drugs are selected according to the duration of cerebral infarction, but the longest intravenous thrombolysis time cannot exceed 6 hours. After 6 hours of cerebral infarction, the vascular structure of the cerebral artery at the infarction lesion is difficult to maintain stability. At this time, if the blood vessels are opened again, the blood pressure will collapse the blood vessels and cause cerebral hemorrhage, which causes more serious damage than the cerebral infarction itself.

Therefore, when using thrombolytic drugs, in order to avoid the risk of cerebral hemorrhage, it is necessary to strictly identify the indications for thrombolytic therapy. Thrombolytic therapy is not suitable for those who have onset for more than 6 hours.

If cerebral infarction occurs within 4.5 hours, alteplase can be selected for thrombolytic therapy. It will only be activated after binding to fibrin, degrading fibrin and dissolving thrombus, which reduces the risk of cerebral hemorrhage.

If cerebral infarction occurs within 6 hours, urokinase can be selected for thrombolytic therapy. Urokinase has a strong effect, which can not only dissolve blood clots, but also degrade coagulation factors such as fibrinogen and thrombin in the blood, leading to a greater risk of cerebral hemorrhage.

If the patient's physical condition is not suitable for thrombolysis, but has hyperfibrinogenemia, defibrinolytic therapy can be considered. Defibrinolytic enzymes or batroxobin have a mild thrombolytic effect and significantly reduce plasma fibrinogen levels, but there is also a risk of bleeding, so they should be used with caution.

3. What to do if you miss the time window

Patients who miss the time window or are not suitable for intravenous thrombolysis or thrombectomy need to receive antiplatelet therapy as soon as possible. Aspirin is the first choice, and those who cannot tolerate it can choose clopidogrel or ticagrelor. You can also consider using two antiplatelet drugs for "dual anti" treatment.

Drugs that improve microcirculation, such as butylphthalide and human urinary kallikrein, can be used to improve collateral circulation and the metabolism of brain tissue.

Neuroprotectants such as edaravone and citicoline can be used to remove free radicals, promote brain function recovery, and reduce brain tissue damage.

If conditions permit, hyperbaric oxygen therapy can be performed to increase oxygen supply to brain cells, reduce brain tissue damage, and improve prognosis.

To sum up, when acute cerebral infarction occurs, rescue is a race against time. The time window for intravenous thrombolysis is within 6 hours. The earlier the blood vessels are reopened, the less damage to the brain. If the time window is missed, drugs can also be used to protect nerves and improve microcirculation, but the prognosis is very different from the effect of intravenous thrombolysis. To rescue acute cerebral infarction, do not delay, actively cooperate with the doctor for thrombolysis, and do not hesitate when relatives sign, in order to obtain the best treatment effect. I am pharmacist Huazi, welcome to follow me and share more health knowledge.