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For newborn infants starved of oxygen during birth there is now evidence that hypothermia therapy for neonatal encephalopathy applied within 6 hours of cerebral hypoxia effectively improves survival and neurological outcome. In adults, however, the evidence is less convincing and the first goal of treatment is to restore oxygen to the brain. The method of restoration depends on the cause of the hypoxia. For mild-to-moderate cases of hypoxia, removal of the cause of hypoxia may be sufficient. Inhaled oxygen may also be provided. In severe cases treatment may also involve life support and damage control measures.
A deep coma will interfere with body's breathing reflexes even after the initial cause of hypoxia has been dealt with; mechanical ventilation may be required. Additionally, severe cerebral hypoxia causes an elevated heart rate, and in extreme cases the heart may tire and stop pumping. CPR, defibrilation, epinephrine, and atropine may all be tried in an effort to get the heart to resume pumping. Severe cerebral hypoxia can also cause seizures, which put the patient at risk of self-injury, and various anti-convulsant drugs may need to be administered before treatment.
There has long been a debate over whether newborn infants with cerebral hypoxia should be resuscitated with 100% oxygen or normal air. It has been demonstrated that high concentrations of oxygen lead to generation of oxygen free radicals, which have a role in reperfusion injury after asphyxia. Research by Ola Didrik Saugstad and others led to new international guidelines on newborn resuscitation in 2010, recommending the use of normal air instead of 100% oxygen.
Brain damage can occur both during and after oxygen deprivation. During oxygen deprivation, cells die due to an increasing acidity in the brain tissue (acidosis). Additionally, during the period of oxygen deprivation, materials that can easily create free radicals build up. When oxygen enters the tissue these materials interact with oxygen to create high levels of oxidants. Oxidants interfere with the normal brain chemistry and cause further damage (this is known as "reperfusion injury").
Techniques for preventing damage to brain cells are an area of ongoing research. Hypothermia therapy for neonatal encephalopathy is the only evidence-supported therapy, but antioxidant drugs, control of blood glucose levels, and hemodilution (thinning of the blood) coupled with drug-induced hypertension are some treatment techniques currently under investigation. Hyperbaric oxygen therapy is being evaluated with the reduction in total and myocardial creatine phosphokinase levels showing a possible reduction in the overall systemic inflammatory process.
In severe cases it is extremely important to act quickly. Brain cells are very sensitive to reduced oxygen levels. Once deprived of oxygen they will begin to die off within five minutes.
Hypothermia treatment induced by head cooling or systemic cooling administered within 6 hours of birth for 72 hours has proven beneficial in reducing death and neurological impairments at 18 months of age. This treatment does not completely protect the injured brain and may not improve the risk of death in the most severely hypoxic-ischemic neonates and has also not been proven beneficial in preterm infants. Combined therapies of hypothermia and pharmacological agents or growth factors to improve neurological outcomes are most likely the next direction for damaged neonatal brains, such as after a stroke.
Treatment remains controversial with regards to the risk/benefit ratio, which differs significantly from treatment of stroke in adults. Presence or possibility of organ or limb impairment and bleeding risks are possible with treatments using antithrombotic agents.
There are some preliminary studies that seem to indicate that treatment with hydrogen sulfide (HS) can have a protective effect against reperfusion injury.
The lack of generally recognized clinical recommendations available are a reflection of the dearth of data on the effectiveness of any particular clinical strategy, but on the basis of present evidence, the following may be relevant:
- Epileptic seizure control with the appropriate use of medication and lifestyle counseling is the focus of prevention.
- Reduction of stress, participation in physical exercises, and night supervision might minimize the risk of SUDEP.
- Knowledge of how to perform the appropriate first-aid responses to seizure by persons who live with epileptic people may prevent death.
- People associated with arrhythmias during seizures should be submitted to extensive cardiac investigation with a view to determining the indication for on-demand cardiac pacing.
- Successful epilepsy surgery may reduce the risk of SUDEP, but this depends on the outcome in terms of seizure control.
- The use of anti suffocation pillows have been advocated by some practitioners to improve respiration while sleeping, but their effectiveness remain unproven because experimental studies are lacking.
- Providing information to individuals and relatives about SUDEP is beneficial.
Currently no effective treatment exists for kernicterus. Future therapies may include neuroregeneration. A handful of patients have undergone deep brain stimulation, and experienced some benefit. Drugs such as baclofen, clonazepam, and artane are often used to manage movement disorders associated with kernicterus. Proton pump inhibitors are also used to help with reflux. Cochlear implants and hearing aids have also been known to improve the hearing loss that can come with kernicterus (auditory neuropathy - ANSD).
Superoxide dismutase is an effective anti-oxidant enzyme which converts superoxide anions to water and hydrogen peroxide. Recent researches have shown significant therapeutic effects on pre-clinical models of reperfusion injury after ischemic stroke.
With due regard for the cause of the coma, and the rapidity of its onset, testing for the purpose of diagnosing death on brainstem death grounds may be delayed beyond the stage where brainstem reflexes may be absent only temporarily – because the cerebral blood flow is inadequate to support synaptic function although there is still sufficient blood flow to keep brain cells alive and capable of recovery. There has recently been renewed interest in the possibility of neuronal protection during this phase by use of moderate hypothermia and by correction of the neuroendocrine abnormalities commonly seen in this early stage.
Published studies of patients meeting the criteria for brainstem death or whole brain death – the American standard which includes brainstem death diagnosed by similar means – record that even if ventilation is continued after diagnosis, the heart stops beating within only a few hours or days. However, there have been some very long-term survivals and it is noteworthy that expert management can maintain the bodily functions of pregnant brain dead women for long enough to bring them to term.
The management of patients pronounced dead on meeting the brainstem death criteria depends upon the reason for diagnosing death on that basis. If the intent is to take organs from the body for transplantation, the ventilator is reconnected and life-support measures are continued, perhaps intensified, with the addition of procedures designed to protect the wanted organs until they can be removed. Otherwise, the ventilator is left disconnected on confirmation of the lack of respiratory centre response.
Neither a standard treatment nor a cure is available. Stimulation of muscle reflexes with electrodes (NMES) has been known to help patients regain some muscle function. Other courses of treatment are often symptomatic. Assistive computer interface technologies, such as Dasher, or OptiKey, combined with eye tracking, may be used to help a LIS survivor communicate with their environment in a better way.
CBPS is commonly treated with anticonvulsant therapy to reduce seizures. Therapies include anticonvulsant drugs, adrenocorticotropic hormone therapy, and surgical therapy, including focal corticectomy and callosotomy. Special education, speech therapy, and physical therapy are also used to help children with intellectual disability due to CBPS.
Mild and moderate cerebral hypoxia generally has no impact beyond the episode of hypoxia; on the other hand, the outcome of severe cerebral hypoxia will depend on the success of damage control, amount of brain tissue deprived of oxygen, and the speed with which oxygen was restored.
If cerebral hypoxia was localized to a specific part of the brain, brain damage will be localized to that region. A general consequence may be epilepsy. The long-term effects will depend on the purpose of that portion of the brain. Damage to the Broca's area and the Wernicke's area of the brain (left side) typically causes problems with speech and language. Damage to the right side of the brain may interfere with the ability to express emotions or interpret what one sees. Damage on either side can cause paralysis of the opposite side of the body.
The effects of certain kinds of severe generalized hypoxias may take time to develop. For example, the long-term effects of serious carbon monoxide poisoning usually may take several weeks to appear. Recent research suggests this may be due to an autoimmune response caused by carbon monoxide-induced changes in the myelin sheath surrounding neurons.
If hypoxia results in coma, the length of unconsciousness is often indicative of long-term damage. In some cases coma can give the brain an opportunity to heal and regenerate, but, in general, the longer a coma, the greater the likelihood that the person will remain in a vegetative state until death. Even if the patient wakes up, brain damage is likely to be significant enough to prevent a return to normal functioning.
Long-term comas can have a significant impact on a patient's families. Families of coma victims often have idealized images of the outcome based on Hollywood movie depictions of coma. Adjusting to the realities of ventilators, feeding tubes, bedsores, and muscle wasting may be difficult. Treatment decision often involve complex ethical choices and can strain family dynamics.
Brainstem death is a clinical syndrome defined by the absence of reflexes with pathways through the brainstem—the “stalk” of the brain, which connects the spinal cord to the mid-brain, cerebellum and cerebral hemispheres—in a deeply comatose, ventilator-dependent patient.
Identification of this state carries a very grave prognosis for survival; cessation of heartbeat often occurs within a few days although it may continue for weeks or even months if intensive support is maintained.
In the United Kingdom, the formal diagnosis of brainstem death by the procedure laid down in the official Code of Practice permits the diagnosis and certification of death on the premise that a person is dead when consciousness and the ability to breathe are permanently lost, regardless of continuing life in the body and parts of the brain, and that death of the brainstem alone is sufficient to produce this state.
This concept of brainstem death is also accepted as grounds for pronouncing death for legal purposes in India and Trinidad & Tobago. Elsewhere in the world the concept upon which the certification of death on neurological grounds is based is that of permanent cessation of all function in all parts of the brain—whole brain death—with which the reductionist United Kingdom concept should not be confused. The United States' President's Council on Bioethics made it clear, in its White Paper of December 2008, that the United Kingdom concept and clinical criteria are not considered sufficient for the diagnosis of death in the United States of America.
The only effective way at preventing kernicterus is to lower the serum bilirubin levels either by phototherapy or exchange transfusion. Visual inspection is never sufficient; therefore, it is best to use a bilimeter or blood test to determine a baby's risk for developing kernicterus. These numbers can then be plotted on the Bhutani nomogram.
Conventional radiotherapy, limited to the involved area of tumour, is the mainstay of treatment for DIPG. A total radiation dosage ranging from 5400 to 6000 cGy, administered in daily fractions of 150 to 200 cGy over 6 weeks, is standard. Hyperfractionated (twice-daily) radiotherapy was used previously to deliver higher radiation dosages, but did not lead to improved survival. Radiosurgery (e.g., gamma knife or cyberknife) has no role in the treatment of DIPG.
Treatment typically consists of radiotherapy and steroids for palliation of symptoms. Radiotherapy may result in minimally extended survival time. Prognosis is very poor, with only 37% of treated patients surviving one year or more. Topotecan has been studied in the treatment of brainstem glioma, otherwise, chemotherapy is probably ineffective, though further study is needed.
Treatment for cerebrovascular disease may include medication, lifestyle changes and/or surgery, depending on the cause.
Examples of medications are:
- antiplatelets (aspirin, clopidogrel)
- blood thinners (heparin, warfarin)
- antihypertensives (ACE inhibitors, beta blockers)
- anti-diabetic medications.
Surgical procedures include:
- endovascular surgery and vascular surgery (for future stroke prevention).
The role of chemotherapy in DIPG remains unclear. Studies have shown little improvement in survival, although efforts (see below) through the Children's Oncology Group (COG), Paediatric Brain Tumour Consortium (PBTC), and others are underway to explore further the use of chemotherapy and other drugs. Drugs that increase the effect of radiotherapy (radiosensitizers) have shown no added benefit, but promising new agents are under investigation. Immunotherapy with beta-interferon and other drugs has also had little effect in trials. Intensive or high-dose chemotherapy with autologous bone marrow transplantation or peripheral blood stem cell rescue has not demonstrated any effectiveness in brain stem gliomas. Future clinical trials may involve medicines designed to interfere with cellular pathways (signal transfer inhibitors), or other approaches that alter the tumor or its environment.
There is no known treatment to reverse nerve damage due to myelomalacia. In some cases, surgery may slow or stop further damage. As motor function degenerates, muscle spasticity and atrophy may occur. Steroids may be prescribed to reduce swelling of the spinal cord, pain, and spasticity.
Research is underway to consider the potential of stem cells for treatment of neurodegenerative diseases. There are, however, no approved stem cell therapies for myelomalacia.
Response to treatment is variable and the long-term and functional outcome is unknown. To provide a basis for improving the understanding of the epidemiology, genotype/phenotype correlation and outcome of these diseases their impact on the quality of life of patients, and for evaluating diagnostic and therapeutic strategies a patient registry was established by the noncommercial International Working Group on Neurotransmitter Related Disorders (iNTD).
It is extremely rare for any significant motor function to return. The majority of locked-in syndrome patients do not regain motor control, but devices are available to help patients communicate. However, some people with the condition continue to live much longer, while in exceptional cases, like that of Kerry Pink and Kate Allatt, a full spontaneous recovery may be achieved.
Brain death is the complete loss of brain function (including involuntary activity necessary to sustain life). It differs from persistent vegetative state, in which the person is alive and some autonomic functions remain.
Brain death is used as an indicator of legal death in many jurisdictions, but it is defined inconsistently. Various parts of the brain may keep functioning when others do not anymore, and the term "brain death" has been used to refer to various combinations. For example, although a major medical dictionary says that "brain death" is synonymous with "cerebral death" (death of the cerebrum), the US National Library of Medicine Medical Subject Headings (MeSH) system defines brain death as including the brainstem. The distinctions can be important because, for example, in someone with a dead cerebrum but a living brainstem, the heartbeat and ventilation can continue unaided, whereas in whole-brain death (which includes brain stem death), only life support equipment would keep those functions going. Patients classified as brain-dead can have their organs surgically removed for organ donation.
Intracerebral hemorrhages is a severe condition requiring prompt medical attention. Treatment goals include lifesaving interventions, supportive measures, and control of symptoms. Treatment depends on the location, extent, and cause of the bleeding. Often, treatment can reverse the damage that has been done.
A craniotomy is sometimes done to remove blood, abnormal blood vessels, or a tumor. Medications may be used to reduce swelling, prevent seizures, lower blood pressure, and control pain.
Treatment depends substantially of the type of ICH. Rapid CT scan and other diagnostic measures are used to determine proper treatment, which may include both medication and surgery.
- Tracheal intubation is indicated in people with decreased level of consciousness or other risk of airway obstruction.
- IV fluids are given to maintain fluid balance, using isotonic rather than hypotonic fluids.
Treatment to remove these tumors always involve radical surgery. The reported recurrence rate for a subtotal removal is 30% after a mean interval period of 8.1 years.
Surgery is the primary treatment for removal of the brain tumor. Use of an endoscope may assist on obtaining a more complete surgical removal.
It has been seen that a few patients have tumors that grow unusually fast, especially after surgery. After surgery it is highly suggested the patients get quarterly MRI's to monitor their tumors or as per neurosurgeons/neurologists order. If monitoring the tumor, it is suggested to use the same facility for each scan. Using different facilities can result in minor variations in the scan which can result in false measurements of the brain tumor.
Intracranial epidermoid tumors are slow growing lesions, which may recur after incomplete removal during surgery, although it will most likely take many years. These slow growing benign brain tumors envelop nerves and arteries rather than displacing them.
Mild cases of hemifacial spasm may be managed with sedation or carbamazepine (an anticonvulsant drug). Microsurgical decompression and botulinum toxin injections are the current main treatments used for hemifacial spasm.