Hypoxia can be described by the lack of oxygen to the cells by two different situations. Blood cells carry oxygen to the different systems throughout the body, so if the blood flow is restricted to any extremity or to any tissue within the body, the consequence will be hypoxia. Also, if the body enters an area of low oxygen within the air, the blood won’t have any oxygen molecules to carry at all. A lack of oxygen can in aviation comes from flying at high altitudes where the air is less dense, therefore less oxygen exists to be consumed through inhalation. The effects of acute hypoxia in the body can be small interferences such as “headache, visual impairment, decrease in muscular coordination, and a decrease in reaction time” (Reinhart, 2008). The effects of severe hypoxia can be described as “deterioration of organ function, neurological manifestations, coma, and may quickly lead to death” (Bhutta, 2022).
As we start to fly more complex aircraft that are capable of cruising at higher altitude into
the physiological deficient zones, we must learn how to recognize the early onset of the life-
threatening situation that is hypoxia. One of the first things hypoxia effects is the brain, which is terrifying since we need our cognitive function in top shape to deal with emergency situations. The very first way to detect a situation like this, is being aware of the pressurization systems in the aircraft and continue to monitor them throughout the flight. You must also be aware of the moment you pass through physiological efficient zone to the deficient zone. A pilot must know what their supplemental oxygen systems are, how they function, and how to utilize them as quickly as possible in the event of a loss of pressure in the cockpit. Situational awareness is always key to successfully flying no matter what debilitating event might occur. Outside of aircraft alarms, detecting hypoxic environments and the onset of hypoxia can be difficult since one of the first symptoms is delayed reaction times, confusion, and a loss of coordination. A couple of physical tells include the “changes of skin color to blue or cherry red, cough, fast heart rate, rapid breathing, and slow heart rate” (DerSarkissian, 2022). Recognizing the physiological symptoms by reviewing them periodically and staying aware of them is crucial to surviving a hypoxic event in the cockpit. Pilots are not driving vehicles down the street that will eventually slow down or crash into a ditch if we lose consciousness. For example, in 1999, a Learjet carrying William Payne Stewart (a well-known pro golfer) crashed after it experienced a loss of cabin pressure resulting in the loss of consciousness for all occupants on board. The plane continued to fly until it eventually ran out of
fuel and crashed in a field outside of Mina, South Dakota, killing all on board. The pilots did not receive supplemental oxygen in time to retain consciousness in this event, and there was no official reason given by the NTSB as to how or why this occurred. A rapid loss of cabin pressure can cause hypoxic stress and symptoms to the body immediately and give pilots very little time to correct this with supplemental oxygen before it’s too late. While many emergency systems exist on board aircraft that travel within hypoxic environments, it is always on the pilot to be situationally aware and prepared for early onset symptoms of hypoxia. The most important thing I learned from studying this topic is how quickly this potentially fatal event can affect the body. Hypoxia can occur within just minutes of a loss of pressure in an aircraft. Specifically, “
Hypoxia occurs within a few minutes if the cabin pressure altitude rises to between 16,000 to 20,000 feet
” (Villegas, 2023). Through independent research and reading this chapter in our book, it is almost impossible to tell, and then react, when
hypoxia occurs. Similar to carbon monoxide poisoning, it is an invisible danger that threatens the
lives of all occupants within pressurized aircraft.
