The treatment for<unk>  depends on the cause. In addition to management of the underlying causes, major considerations in acute treatment of increased<unk>  relates to the management of stroke and cerebral trauma. For long-term or chronic forms of raised<unk> , especially idiopathic<unk>  hypertension (IIH), a specific type of diuretic medication (acetazolamide) is used. In cases of confirmed brain neoplasm, dexamethasone is given to decrease<unk> . Although the exact mechanism is unknown, current research shows that dexamethasone is capable of decreasing peritumoral water content and local tissue pressure to decrease<unk> . Ventilation In people who have high<unk>  due to an acute injury, it is particularly important to ensure adequate airway, breathing, and oxygenation. Inadequate blood oxygen levels (hypoxia) or excessively high carbon dioxide levels (hypercapnia) cause cerebral blood vessels to dilate, increasing the flow of blood to the brain and causing the<unk>  to rise. Inadequate oxygenation also forces brain cells to produce energy using anaerobic metabolism, which produces lactic acid and lowers pH, also dilating blood vessels and exacerbating the problem. Conversely, blood vessels constrict when carbon dioxide levels are below normal, so hyperventilating a person with a ventilator or bag valve mask can temporarily reduce<unk> . Hyperventilation was formerly a part of the standard treatment of traumatic brain injuries, but the induced constriction of blood vessels limits blood flow to the brain at a time when the brain may already be ischemic—hence it is no longer widely used. Furthermore, the brain adjusts to the new level of carbon dioxide after 48 to 72 hours of hyperventilation, which could cause the vessels to rapidly dilate if carbon-dioxide levels were returned to normal too quickly. Hyperventilation is still used if<unk>  is resistant to other methods of control, or there are signs of brain herniation, because the damage herniation can cause is so severe that it may be worthwhile to constrict blood vessels even if doing so reduces blood flow.<unk>  can also be lowered by raising the head of the bed, improving venous drainage. A side effect of this is that it could lower pressure of blood to the head, resulting in a reduced and possibly inadequate blood supply to the brain. Venous drainage may also be impeded by external factors such as hard collars to immobilize the neck in trauma patients, and this may also increase the<unk> . Sandbags may be used to further limit neck movement. Medication In the hospital, the blood pressure can be increased in order to increase CPP, increase perfusion, oxygenate tissues, remove wastes, and thereby lessen swelling. Since hypertension is the body's way of forcing blood into the brain, medical professionals do not normally interfere with it when it is found in a person with a head injury. When it is necessary to decrease cerebral blood flow, MAP can be lowered using common antihypertensive agents such as calcium channel blockers. If there is an intact blood–brain barrier, osmotherapy (mannitol or hypertonic saline) may be used to decrease<unk> . It is unclear whether mannitol or hypertonic saline is superior, or if they improve outcomes. Struggling, restlessness, and seizures can increase metabolic demands and oxygen consumption, as well as increasing blood pressure. Analgesia and sedation are used to reduce agitation and metabolic needs of the brain, but these medications may cause low blood pressure and other side effects. Thus if full sedation alone is ineffective, people may be paralyzed with drugs such as atracurium. Paralysis allows the cerebral veins to drain more easily, but can mask signs of seizures, and the drugs can have other harmful effects. Paralysing drugs are only introduced if patients are fully sedated (this is essentially the same as a general anaesthetic) Surgery Craniotomies are holes drilled in the skull with the help of cranial drills to remove<unk>  hematomas or relieve pressure from parts of the brain. As raised<unk> 's may be caused by the presence of a mass, removal of this via craniotomy will decrease raised<unk> 's. A drastic treatment for increased<unk>  is decompressive craniectomy, in which a part of the skull is removed and the dura mater is expanded to allow the brain to swell without crushing it or causing herniation. The section of bone removed, known as a bone flap, can be stored in the patient's abdomen and resited back to complete the skull once the acute cause of raised<unk> 's has resolved. Alternatively a synthetic material may be used to replace the removed bone section (see cranioplasty)
Intracranial pressure
Cerebral perfusion pressure
Cerebral autoregulation
Mean arterial pressure
Intraocular pressure
Blood volume
Segmental blood pressure
Blood pressure