Hypoxia is a pathological condition where is is a deficiency of oxygen in the whole body (generalized hypoxia) or in a part of the body (tissue hypoxia). Depending on the conditions, a person may need different amount of arterial oxygen concentration level; for example during running, the runner would require higher oxygen level. A hypoxic condition is when the oxygen supply does not meet its demand. Anoxia is a condition when there is no oxygen at all.
Hypoxemia is the situation when the oxygen saturation level in the arterial is abnormally low and hypoxemia is not equivalent to hypoxia. A person may experience hypoxia because of anemia and yet has high blood oxygen saturation level.
There are five different types of hypoxia: hypoxic, anemic, hypemic, histotoxic, and stagnant. Hypoxic hypoxia occurs when the entire body doesn't receive an appropriate amount of oxygen supply, and as a result, there is a low partial pressure of oxygen in the arterial blood. Potential causes of Hypoxic hypoxia entail high altitude ascension, sleep apnea, inappropriate ventilation, or a heart mechanism failure. Anemic hypoxia is when the arterial blood pressure is normal, but there is a lowered total oxygen blood content. Hypemic hypoxia is when there is a problem obstructing the ability of the blood to deliver oxygen, this is most often caused by carbon monoxide poisoning and an unusual form of haemoglobin. Histotoxic is when the appropriate amount of oxygen is reaching the cells, but there is a disorder prohibiting the cells to utilize the oxygen effectively. Lastly, there is a stagnant hypoxia, where there is something obstructing the flow of blood, even though the blood has an adequate amount of oxygen.
Generalized hypoxia can occur in a low oxygen environment, such as high altitude and diving. This cau cause dizziness and lead to potentially fatal complications. Training can increase a person's tolerance to low oxygen environment. For example, mild and non-damaging intermittent hypoxia is used intentionally during altitude trainings to develop an athletic performance adaptation at both the systemic and cellular level. During such training, it is important to monitor one's blood oxygen saturaion level using a finger pulse oximeter.
Symptoms of hypoxia
The symptoms of hypoxia depend on its severity and acceleration of onset. They may develop gradually and would take a long period of time as in the case of altitude sickness. The primary symptoms are:
- headaches
- fatigue
- shortness of breath
- feeling of euphoria
- nausea
- Hot and cold flashes
- Visual Impairment
The symptoms can also occur in a very short time and become deadly. They are:
- blue discolouration of the skin (cyanosis)
- priapism
- coma
- seizures
- changes in levels of consciousness
Treatment
The key is to reduce the difference between oxygen available and the need. For example, the patient should be resting, instead of continuing exercising; the patient's airway should be clear and no blockage; apply oxygen if available. Call for medical help as soon as possible.
Recovery is possible when the brain has not been deprived of oxygen for a long period. Therefore, it is necessary to give adequate air and medical aid to the person suffering from hypoxia.
Hypoxia, or hypoxiation, is a pathological condition in which the body as a whole (generalized hypoxia) or a region of the body (tissue hypoxia) is deprived of adequate oxygen supply. Variations in arterial oxygen concentrations can be part of the normal physiology, for example, during strenuous physical exercise. A mismatch between oxygen supply and its demand at the cellular level may result in a hypoxic condition. Hypoxia in which there is complete deprivation of oxygen supply is referred to as anoxia.
Hypoxia differs from hypoxemia. In the latter, the oxygen concentration within the arterial blood is abnormally low.[1] It is possible to experience hypoxia and have a low oxygen content (e.g., due to anemia) but maintain high oxygen partial pressure (pO2). Incorrect use of these terms can lead to confusion, especially as hypoxemia is among the causes of hypoxia (in hypoxemic hypoxia).
Generalized hypoxia occurs in healthy people when they ascend to high altitude, where it causes altitude sickness leading to potentially fatal complications: high altitude pulmonary edema (HAPE) and high altitude cerebral edema (HACE).[2] Hypoxia also occurs in healthy individuals when breathing mixtures of gases with a low oxygen content, e.g. while diving underwater especially when using closed-circuit rebreather systems that control the amount of oxygen in the supplied air. A mild and non-damaging intermittent hypoxia is used intentionally during altitude trainings to develop an athletic performance adaptation at both the systemic and cellular level.[3]
Hypoxia is also a serious consequence of preterm birth in the neonate. The main cause for this is that the lungs of the human foetus are among the last to develop during pregnancy. To assist the lungs to distribute oxygenated blood throughout the body infants at risk of hypoxia are often placed inside an incubator capable of providing http://en.wikipedia.org/wiki/Continuous_positive_airway_pressure . , also known as a humidicrib.
The symptoms of generalized hypoxia depend on its severity and acceleration of onset. In the case of altitude sickness, where hypoxia develops gradually, the symptoms include headaches, fatigue, shortness of breath, a feeling of euphoria and nausea. In severe hypoxia, or hypoxia of very rapid onset, changes in levels of consciousness, seizures, coma, priapism, and death occur. Severe hypoxia induces a blue discolouration of the skin, called cyanosis. Because hemoglobin is a darker red when it is not bound to oxygen (deoxyhemoglobin), as opposed to the rich red colour that it has when bound to oxygen (oxyhemoglobin), when seen through the skin it has an increased tendency to reflect blue light back to the eye. In cases where the oxygen is displaced by another molecule, such as carbon monoxide, the skin may appear 'cherry red' instead of cyanotic.
Hypoxia can be a fatal condition. If someone if suffering from hypoxia, it is very important to establish the airway by assisted breathing. The individual should immediately be taken to a hospital, where he should be put on a ventilator to assist in breathing. The blood pressure and heart rate should be monitored. They should be kept in control with the help of fluids or medicines. Seizures, if any, should be suppressed. Sometimes cold blankets are used as they slow down the activity of the brain cells and decrease the need of oxygen. These should be the first steps in the treatment of hypoxia, before the underlying cause is treated.
During the path to recovery, the patient may experience amnesia, personality regression, hallucinations, memory loss, muscle spasms and twitches.
Recovery is possible when the brain has not been deprived of oxygen for a long period. Therefore, it is necessary to give adequate air and medical aid to the person suffering from hypoxia.
