What is Anoxic Brain Injury
An anoxic brain injury is the result of a limited amount of oxygen supply to the brain. A process known as apoptosis is responsible for the death of neural cells when deprived of oxygen for an extended period.
The simultaneous death of great numbers of brain cells can leave you with lessened mind function. When subjected to further oxygen deprivation, anoxic brain injuries could be fatal.
Symptoms of Anoxic Brain Injuries
Anoxic brain injury symptoms depend on the severity of the damage and the extent/duration of anoxia. The most vulnerable regions of the brain include the basal ganglia, the cerebral cortex, the cerebellum, and the hippocampus.
Short-Term Effects
When the duration of anoxia is relatively shorter, the earliest symptoms will include short-term memory loss and a lack of concentration, attention, and coordination. Other initial symptoms include dizziness, headaches, hyperventilation, and sweating.
The severity of brain damage is directly proportional to the length of time that the anoxia persists. In the case of longer durations, the earliest symptoms include agitation, confusion, peripheral cyanosis (blueish discolouration of the skin around the mouth, fingertips, and lips), seizures, and myoclonus (an uncontrolled contraction of muscles).
Extreme anoxia can result in a coma or loss of consciousness.
In rare cases, severe anoxia damages the pituitary and hypothalamus gland. It can lead to the emergence of neurogenic diabetes insipidus and hormonal imbalance. Neurogenic diabetes insipidus is a complication caused by insufficient vasopressin (ADH) secretion in the brain. Its characteristics include excessive urination and increased thirst.
Long-Term Effects
Long-term effects primarily depend on the regions of damage and the extent of the irreversibility of the brain damage. Symptoms such as movement disorders, memory lapses, weakness of legs and arms, stress intolerance, and depression could manifest after recovery.
Anoxic brain injury to the basal ganglia, cerebellum, or cerebral cortex could lead to impaired balance, coordination, and locomotion. Also, any damage to the cerebral cortex’s occipital lobe could result in cortical blindness. Memory-related problems arise from a damaged hippocampus.
Damage to the dominant hemisphere’s frontal lobe results in speech problems and impaired decision-making, reasoning, and thinking. It could also lead to changes in mood, social behavior, and personality.
What Causes Anoxic Brain Injury?
1. Low Blood Pressure
Hypotension, or low blood pressure, is a condition whereby the blood pressure is low enough to result in inadequate blood flow to the organs. In such a case, insufficient amounts of oxygen and blood supply to the brain could lead to anoxic brain injury.
2. Choking
Choking is the partial or complete obstruction of the trachea and leads to difficulty in breathing. Failing to dislodge the source of the obstruction could result in devastating effects. Choking suggests that they are insufficient oxygen supply to the brain, which could lead to anoxic brain injury.
3. Stroke
A stroke occurs due to the reduced or interrupted supply of blood to parts of the brain. This prevents brain tissue from obtaining nutrients and oxygen, which could potentially lead to the death of the affected tissue.
4. Carbon Monoxide Poisoning
Carbon Monoxide (CO) is an odorless and colorless gas that prevents the body from acquiring oxygen. It prohibits oxygen from getting to vital organs such as the lungs or brain. Symptoms of carbon monoxide poisoning include nausea and a dizzy feeling. Carbon monoxide poisoning leads to loss of consciousness or even death.
5. Cardiac Arrest
The primary function of the heart is to circulate blood through the entirety of the body, which means that a defective heart is incapable of circulating vital nutrients and oxygen to organs such as the brain at an adequate rate.
6. Near Drowning
The oxygen supply to all parts of the body drastically decreases when the lungs fill with water. The lack of oxygen could lead to cardiac arrest or anoxic brain injury.
7. Drug Overdose
Both recreational and prescription drugs heavily influence the various mechanisms required to maintain the breathing process. For example, prescription opioids slow down the heart rate and respiration process. It could result in limited oxygen supply to the brain, which leads to anoxic brain injury.
Recovery
The uniqueness of each case of anoxic brain injury makes the recovery process difficult to predict. Complete recovery from a severe anoxic brain injury is unlikely. However, numerous patients with moderate anoxic brain injuries have made partial or full recoveries. This is because the effects and symptoms of the damage depend on the affected region of the brain.
According to various studies, the application of barbiturates slows down brain activity. This could be helpful within the first couple of days after the injury. However, the conventional medical procedure is to sustain the body’s status.
The extent to which you can recover is only considered once your condition has stabilized. The recovery process can take months or years. In most cases, the patient fails to regain his or her earlier level of functioning. It is, therefore, advisable to start the rehabilitation process as soon as possible.
During the rehabilitation process, interaction with a range of professionals is expected. For example, you will probably interact with a physical therapist that specializes in enhancing motor skills. An occupational therapist will help in retraining you in performing day-to-day skills such as going to the bathroom or dressing.
Speech therapists assist in addressing cognitive problems and language disorders. A neuropsychologist assesses the type and level of cognitive impairment, collaborates the retraining, and assists with behavioral and emotional issues.
Anoxic Brain Injury Life Expectancy
A recent study concluded that individuals with anoxic brain injuries die at a higher rate compared to those with no such injuries. The study also concluded that some of the causes of these deaths are preventable. Research has also found anoxic brain injury to decrease life expectancy by approximately eight years.
The life expectancy for moderate or severe cases of anoxic brain injury depends on sex, age, and the weight of disability. Those with the most severe disabilities, such as those that cannot walk or feed themselves, have the least life expectancy.
On the other hand, those that can walk on their own have a longer life expectancy. It proves that feeding and walking skills are excellent predictions of life expectancy. These skills are easily assessable and allow for reliable differentiation between patients with mild disabilities and those with severe disabilities.
The study also demonstrated that the life expectancy for people with mild to severe anoxic brain injury has hardly changed over the past 20 years.