Brain deathBrain death is the permanent, irreversible, and complete loss of brain function which may include cessation of involuntary activity necessary to sustain life. It differs from persistent vegetative state, in which the person is alive and some autonomic functions remain. It is also distinct from comas as long as some brain and bodily activity and function remain, and it is also not the same as the condition locked-in syndrome. A differential diagnosis can medically distinguish these differing conditions.
InjuryAn injury is any physiological damage to living tissue caused by immediate physical stress. An injury can occur intentionally or unintentionally and may be caused by blunt trauma, penetrating trauma, burning, toxic exposure, asphyxiation, or overexertion. Injuries can occur in any part of the body, and different symptoms are associated with different injuries. Treatment of a major injury is typically carried out by a health professional and varies greatly depending on the nature of the injury.
HypothermiaHypothermia is defined as a body core temperature below in humans. Symptoms depend on the temperature. In mild hypothermia, there is shivering and mental confusion. In moderate hypothermia, shivering stops and confusion increases. In severe hypothermia, there may be hallucinations and paradoxical undressing, in which a person removes their clothing, as well as an increased risk of the heart stopping. Hypothermia has two main types of causes. It classically occurs from exposure to cold weather and cold water immersion.
Mouth-to-mouth resuscitationMouth-to-mouth resuscitation, a form of artificial ventilation, is the act of assisting or stimulating respiration in which a rescuer presses their mouth against that of the victim and blows air into the person's lungs. Artificial respiration takes many forms, but generally entails providing air for a person who is not breathing or is not making sufficient respiratory effort on their own. It is used on a patient with a beating heart or as part of cardiopulmonary resuscitation (CPR) to achieve the internal respiration.
Underwater divingUnderwater diving, as a human activity, is the practice of descending below the water's surface to interact with the environment. It is also often referred to as diving, an ambiguous term with several possible meanings, depending on context. Immersion in water and exposure to high ambient pressure have physiological effects that limit the depths and duration possible in ambient pressure diving.
Scuba divingScuba diving is a mode of underwater diving whereby divers use breathing equipment that is completely independent of a surface air supply, and therefore has a limited but variable endurance. The name "scuba", an acronym for "Self-Contained Underwater Breathing Apparatus", was coined by Christian J. Lambertsen in a patent submitted in 1952. Scuba divers carry their own source of breathing gas, usually compressed air, affording them greater independence and movement than surface-supplied divers, and more time underwater than free divers.
Pulmonary aspirationPulmonary aspiration is the entry of material such as pharyngeal secretions, food or drink, or stomach contents from the oropharynx or gastrointestinal tract, into the larynx (voice box) and lower respiratory tract, the portions of the respiratory system from the trachea (windpipe) to the lungs. A person may inhale the material, or it may be delivered into the tracheobronchial tree during positive pressure ventilation. When pulmonary aspiration occurs during eating and drinking, the aspirated material is often colloquially referred to as "going down the wrong pipe".
BarotraumaBarotrauma is physical damage to body tissues caused by a difference in pressure between a gas space inside, or contact with, the body and the surrounding gas or liquid. The initial damage is usually due to over-stretching the tissues in tension or shear, either directly by an expansion of the gas in the closed space or by pressure difference hydrostatically transmitted through the tissue.
Oxygen therapyOxygen therapy, also referred to as supplemental oxygen, is the use of oxygen as medical treatment. Supplemental oxygen can also refer to the use of oxygen enriched air at altitude. Acute indications for therapy include hypoxemia (low blood oxygen levels), carbon monoxide toxicity and cluster headache. It may also be prophylactically given to maintain blood oxygen levels during the induction of anesthesia. Oxygen therapy is often useful in chronic hypoxemia caused by conditions such as severe COPD or cystic fibrosis.
Cardiopulmonary resuscitationCardiopulmonary resuscitation (CPR) is an emergency procedure consisting of chest compressions often combined with artificial ventilation, or mouth to mouth in an effort to manually preserve intact brain function until further measures are taken to restore spontaneous blood circulation and breathing in a person who is in cardiac arrest. It is recommended for those who are unresponsive with no breathing or abnormal breathing, for example, agonal respirations.
Cerebral hypoxiaCerebral hypoxia is a form of hypoxia (reduced supply of oxygen), specifically involving the brain; when the brain is completely deprived of oxygen, it is called cerebral anoxia. There are four categories of cerebral hypoxia; they are, in order of increasing severity: diffuse cerebral hypoxia (DCH), focal cerebral ischemia, cerebral infarction, and global cerebral ischemia. Prolonged hypoxia induces neuronal cell death via apoptosis, resulting in a hypoxic brain injury.
LifeguardA lifeguard is a rescuer who supervises the safety and rescue of swimmers, surfers, and other water sports participants such as in a swimming pool, water park, beach, spa, river and lake. Lifeguards are trained in swimming and CPR/AED first aid, certified in water rescue using a variety of aids and equipment depending on requirements of their particular venue. In some areas, lifeguards are part of the emergency services system to incidents and in some communities, lifeguards may function as the primary EMS provider.
Pulmonary edemaPulmonary edema, also known as pulmonary congestion, is excessive liquid accumulation in the tissue and air spaces (usually alveoli) of the lungs. It leads to impaired gas exchange and may cause hypoxemia and respiratory failure. It is due to either failure of the left ventricle of the heart to remove oxygenated blood adequately from the pulmonary circulation (cardiogenic pulmonary edema), or an injury to the lung tissue directly or blood vessels of the lung (non-cardiogenic pulmonary edema).
Major traumaMajor trauma is any injury that has the potential to cause prolonged disability or death. There are many causes of major trauma, blunt and penetrating, including falls, motor vehicle collisions, stabbing wounds, and gunshot wounds. Depending on the severity of injury, quickness of management, and transportation to an appropriate medical facility (called a trauma center) may be necessary to prevent loss of life or limb.
Artificial ventilationArtificial ventilation (also called artificial respiration) is a means of assisting or stimulating respiration, a metabolic process referring to the overall exchange of gases in the body by pulmonary ventilation, external respiration, and internal respiration. It may take the form of manually providing air for a person who is not breathing or is not making sufficient respiratory effort, or it may be mechanical ventilation involving the use of a mechanical ventilator to move air in and out of the lungs when an individual is unable to breathe on their own, for example during surgery with general anesthesia or when an individual is in a coma or trauma.
Life supportLife support comprises the treatments and techniques performed in an emergency in order to support life after the failure of one or more vital organs. Healthcare providers and emergency medical technicians are generally certified to perform basic and advanced life support procedures; however, basic life support is sometimes provided at the scene of an emergency by family members or bystanders before emergency services arrive. In the case of cardiac injuries, cardiopulmonary resuscitation is initiated by bystanders or family members 25% of the time.
ApneaApnea, BrE: apnoea, is the temporal cessation of breathing. During apnea, there is no movement of the muscles of inhalation, and the volume of the lungs initially remains unchanged. Depending on how blocked the airways are (patency), there may or may not be a flow of gas between the lungs and the environment. If there is sufficient flow, gas exchange within the lungs and cellular respiration would not be severely affected. Voluntarily doing this is called holding one's breath.
AutopsyAn autopsy (post-mortem examination, obduction, necropsy, or autopsia cadaverum) is a surgical procedure that consists of a thorough examination of a corpse by dissection to determine the cause, mode, and manner of death; or the exam may be performed to evaluate any disease or injury that may be present for research or educational purposes. For animals, the term necropsy is generally reserved. Autopsies are usually performed by a specialized medical doctor called a pathologist.
First aidFirst aid is the first and immediate assistance given to any person with either a minor or serious illness or injury, with care provided to preserve life, prevent the condition from worsening, or to promote recovery until medical services arrive. First aid is generally performed by someone with basic medical training. Mental health first aid is an extension of the concept of first aid to cover mental health, while psychological first aid is used as early treatment of people who are at risk for developing PTSD.
Diving reflexThe diving reflex, also known as the diving response and mammalian diving reflex, is a set of physiological responses to immersion that overrides the basic homeostatic reflexes, and is found in all air-breathing vertebrates studied to date. It optimizes respiration by preferentially distributing oxygen stores to the heart and brain, enabling submersion for an extended time. The diving reflex is exhibited strongly in aquatic mammals, such as seals, otters, dolphins, and muskrats, and exists as a lesser response in other animals, including human babies up to 6 months old (see infant swimming), and diving birds, such as ducks and penguins.
