Hypobaric Hypoxia: Causes and Treatment - Research Paper Example

Name Course Lecturer Date Hypobaric hypoxia Introduction It goes without saying that oxygen is significant for every living thing; without it, there would be no life. This is attributed to the fact that oxygen is the major composition of air that is basically needed to maintain body functions as it is involved in various processes including oxidation or breaking down of complex material, taken as food so as to produce energy. Indeed, lack of enough oxygen in the body results to various conditions that are harmful to the body. Hypobaric hypoxia is one of the common conditions related to lack of sufficient oxygen supply to the body tissues associated with increase in altitude; as such, it is mostly experienced type of hypoxia in flights. Hypobaric hypoxia is primarily a condition whereby body tissues lack sufficient oxygen, both in molecular or quantity concentration, as the body is deprived oxygen from the atmosphere. This condition affects the ability of the body to carry oxygen to the bloodstream from the lungs. Of important to note is the fact that this condition does not mean the red blood cells is few therefore, unable to carry oxygen, but it simply implies that the oxygen molecules that are expected to be carried from the lungs to the rest of the body are not sufficient. As noted earlier, the condition often occurs when an individual is at a higher altitude. It may result to loss of cognition that is harmful especially for pilots who are expected to make sound decision to ensure the safety of the crew and passengers on board. With this, the paper seeks to explore general understanding of hypobaric hypoxia, is cause, signs and symptoms, prevention and treatment. Hypobaric hypoxia Hypobaric hypoxia is recognized to be one of the most serious physiological hazards that affect people above 10,000ft; and mostly during the flight altitude. This is attributed to the fact that during an ascent, there is a fall in the barometric pressure, therefore, an individual breathes in ambient air that leads to fall of partial pressure, making molecular concentration or content insufficient (Gradwell and Rainfold 42). Above the aforementioned height, it is generally argued that there is a need for supplementary oxygen to be available. As such, most aircraft tend to be pressurized at approximately 5,000ft so as prevent hypoxia. Notably, in individuals who are fatigued, ill or stressed, signs of this conditions may be seen as low as at 6,000ft. Of important to note is the fact that when an aircraft ascends gradually to about 50,000ft, oxygen partial pressure is decreased to a level that is about 10 per cent of that found in the lung at sea level. In such a scenario, a pilot has about 14 seconds to respond to the altitude and insufficient air before becoming unconscious (Gradwell and Rainfold 44). Additionally, at this state, the pilot has about 4 minutes before causing death or even dying. It is worth noting that vulnerability to death or unconsciousness may be further increased by other factors that reduce the level or concentration of oxygen including drugs that may limit the activity of the brain (Robinson 78). Most importantly, the situation is worsen at night due to the poor visibility that is a result of the condition; this is especially so for pilots who are flying VFR (Christiansen et al 67). With the above, it s quite clear that hypobaric hypoxia is an interesting area for researchers and aviators given that the neurological effects have an effect on the flying crew as it impairs mental performance endangering people on board. Equally enough, the hypobaric hypoxia is generally believed to increase the risks for pilots to do mistakes on psychomotor and cognitive activities; furthermore causing impairment of the body senses (Robinson 70). Basically, despite the expertise of the pilots, given the fact that there is that particular height that the concentration of the body decreases, a mistake is expected to be made due to poor judgement which is as a result of impairment of the brain. For instance, according to (Gradwell and Rainfold 56)in the past, it is argued that most insufficient oxygen caused a usual toll of aircraft and lives; indeed, most military air individuals died as a result of hypoxia while others were unable to perform the duties due to their impairment despite the expertise in the area. As a result of the above, most of the military personnel received high standard training; as such have an opportunity to gain experience of the condition even under controlled conditions in the hypobaric hypoxia chambers (Gradwell and Rainfold 59). On the same note, it is significant to note that civilian flying crews are not exempted from this condition. This is despite the fact that the aircrew may not have received the same kind of training as the military personnel. Indeed, tragic accidents have been reported in which the crews and passengers have perished as a result of hypobaric hypoxia at very high attitudes. In a recent study of aviation accidents, it was reported that in-flight hypobaric hypoxia was the main cause of these accidents due to the incapacitation or impairment in more than five per cent of the reported cases (Christiansen et al 56). As such, notwithstanding that there are improvement made in relation to this condition in the aviation industry in regard to reliability and performance of oxygen delivery and cabin pressurization systems, accidents and incident still occurs due to the condition. Therefore, it is important that the constant vigilance and awareness is continued as it is essential in the aviation community so as to decrease the accidents as a result of the condition (Robinson 67). Causes of Hypobaric Hypoxia With the above, it is important to analyze the causes of hypobaric condition. In this regard, there are three major principal cause of hypobaric hypoxia in flight; rising to higher altitude without additional oxygen, failure of individual breathing system and equipment to supply adequate oxygen concentration or pressure, and at high attitude, the decompression of pressure cabin (Christiansen et al 44). With regard to the above, it is important to note that both air density and air pressure always decrease with increase in attitude. Therefore, when an aircraft ascends, the density of air is seen to reduce causing lack of sufficient being transferred to the lungs then the bloodstream. In the air force, for instance, it has been reported that almost half of the incidents related to hypobaric hypoxia are as a result of decompression of cabins and malfunction of oxygen regulators. Additionally, according to (Christiansen et al 45) further studies have showed that about 62 per cent of cases of hypobaric hypoxia in flights arose from malfunction of the regulator or the mask. Physiological effects of hypobaric hypoxia may be considered in three key areas including; cardiovascular and respiratory response to insult, the neurological impact of this insult and the general response to it. On the other hand, clinical impact or consequences are expected to be as a result of a combination of changes perceived in the aforementioned areas (Christiansen et al 79). Under these responses to hypobaric hypoxia, it is important to note that psychological changes occur gradually as one ascends at a rate of about 2000 to 3000 feet per minute. However, the changes may occur abruptly in case there is malfunction in delivery of oxygen equipment, and fastest after quick decompression. Notably, it is rare for hypobaric hypoxia to be caused by breathing air in any professional aircrew; nevertheless, it has been reported in a number of leisure flying including individuals flying in balloons, gliders and light aircraft (Robinson 97). It is worth noting under neurological effects, the impairment of psychological performance as a result of lack of sufficient oxygen at a high altitude, is of great importance to aviation. However, in relation to this, it has been noted that there is a difference between and within individual exposed to the condition. This variation is regarded to be as a result of differences in respiratory response to hypobaric hypoxia. In regard to the clinical features of hypobaric hypoxia, it is worth noting that the picture of the condition is primarily a combination of neurological effects and cardio respiratory responses and at the same time, the signs and symptoms vary. The order and the speed of appearance of symptoms together their severity generally depends on the degree and the exposure to low oxygen and the rate at which the oxygen is being lowered (Gradwell and Rainfold 89). However, it is important to note that, keeping the aforementioned factors constants, there is a noted variation between individual in the impact of hypoxia. Regardless of the difference, the pattern or trend of symptoms appearance is said to be similar in most individual (Gradwell and Rainfold 90). Signs and Symptoms There are several factors that have been considered significant in relation to influencing individual trend or pattern of signs and symptoms as a result of hypoxia. They include: physical activity, ambient temperature, use of various drugs including alcohol, intercurrent illness and intensity of hypoxia. Under ambient temperature, it is generally believed that a cold environment tend to reduce a tolerance to lack of oxygen due to increase in metabolic activities; intensity of hypoxia mainly include various factors such as duration of exposure to high altitude, maximum attitude and the rate of ascending (Robinson 99). On the other hand, under the use of drugs, it is generally agreed that substances that have active pharmacological activities have the same effect as those of hypoxic hypoxia and as such exacerbate or mimic hypobaric hypoxia. Additionally, preparations and alcohol re said to cause severe problems. Similarly, further metabolic load brought about by other diseases will increase an exposure to hypoxia. Still, any physical activity is also likely to exacerbate the symptoms of hypobaric hypoxia and in most cases results to unconsciousness (Robinson 100). More specifically, it is important to consider the clinical picture with varying attitude. For up to 10,000ft breathing air, a resting object; that is individual, will register no symptoms; however, performance of various activities will somehow be impaired. From 10,000 to about 15,000ft breathing air, a warm resting object will show no to few signs; in fact, at this level, there are no symptoms perceived. However, at this level, the ability to do any activity is impaired but the individual is unaware. Notably, prolonged exposure to this moderate hypoxia results to severe headache, and reduction of any physical activity. An increase in temperature at this level may induce symptoms of hypoxia. An altitude of 15,000 to 20,000ft breathing air results to appearance of both signs and symptoms on a resting object. In this level higher neuromuscular and mental processes are affected; more so, loss of willpower and critical judgement. Due to loss of self criticism an individual is often unaware of deterioration in performance of any activity or even the presence of the condition; a situation that is considered dangerous in aviation (Robinson 102). Additionally, mental calculations are affected and therefore, considered unreliable, thought processes are gradual reduced, and at the same time there is impairment of psychomotor performance. In most cases observable changes occur in the emotional state leading to disinhibition of primary individual emotions and traits; as such an individual may become euphoric, elated, depressed and pugnacious. Furthermore, there are cases where an individual becomes physically violent (Christiansen et al 89). In addition to the above cerebral features, due to hypocapnia, disturbance may occur and it is generally believed that it may control clinical picture. Visual disturbance, light-headedness, and paraesthesiae of lips and extremities may be accompanied by tetany with facial spasms and carpo pedal. In addition to this, peripheral and central cyanosis is seen to develop accompanied by a decrease in muscular condition, loss if various sense including touch making fine or delicate movements impossible. Of important to note in this level, any physical exertion highly increase not only the speed but also the severity of the inception of the symptoms and in most cases is said to lead to unconsciousness (Gradwell and Rainfold 77). Above 20,000ft on the other hand, an individual primarily shows emphasis of signs and symptoms that have been described above. Mental and comprehension performance reduce gradually and unconsciousness may appear without any warning. Myoclonic jerks mainly of the upper limbs are in most cases follow unconsciousness and convulsion may follow later. It is important to note most often, hypoxic convulsions are featured by maintained and forceful muscular contractions that results to production of opisthotonos (Christiansen et al 90). In relation to this, it is significance also to consider some symptoms that are mainly experienced by pilots. They include; reduced visual acuity resulting to difficultly in focusing, poor visual accommodations especially from a near to far distance, difficulties in shifting seating position, drowsiness, fatigue, reduction in any pain sensation, poor reaction to light, needles and pins in toes and fingers, aggressiveness, depression and euphoria. Prevention and Treatment Given the effects of hypobaric hypoxia on one’s body, it is therefore, important to consider various factors that may prevent the occurrence of this condition. Indeed, as (Gradwell and Rainfold 99) states, precautions should be considered before one fly so as to reduce the suffering of this condition, in case it takes place. It is important that one remain hydrated; as such before taking a flight, it is recommended that lots of fluids are taken to minimize dehydration. In relation to this, one should not take alcohol or any other drink a day before flying that may dehydrate the body. In most cases, cases or symptoms of fatigue are reduced by plenty of rest and sleep prior to flying. Additionally, sleeping may to some extent reduce the symptoms of irritation and depression that come along with hypoxia. Other precautions include reduction of smoking, no intake of sedatives, mental and physical fitness, cabin pressurization and training especially among the crew members, and improvement of quality of aircrafts. Regardless the efforts of increasing awareness, training of pilots, enhancement of the quality of aircrafts in order to eliminate occurrence of the condition, it is important to understand treatment that is carried in case a pilot, crew member or passengers gets the condition. The suggested treatments include administration of additional oxygen through a mask and in case of a pilot, reduction of altitude. Conclusion Indeed, high altitude, especially in aviation has been reported to cause various dangers to only to the pilot but also to the crew members and passengers. As discussed in the paper, hypobaric hypoxia is one of the commonest conditions that is related to high altitude due to decrease in supply of sufficient oxygen to the body. The paper has clearly discussed the causes of the conditions and at the same time related the causes to signs and symptoms that are experienced at various altitudes during flying. Equally enough, the paper has noted various clinical and physiological features that occur as a result of the condition. Given that this condition primarily endangers lives especially in commercial flights, it is important that various precautions as noted in the paper to be considered. This should be accompanied by various treatments, in this case, first aid, in case a condition is reported during a flight. It is important to note that training of pilots and quality of aircrafts majorly plays a role in reducing hypobaric hypoxia; as such, it should be considered by all airlines in order to minimize accidents that may be reported as a result of this condition. Work cited; Christiansen, Claus, Jorg Draeger and Jurgen Kriebel. Principal and practice of aviation medicine. New York: World Scientific, 2005. Print. Gradwell, David and David Rainfold. Ernsting's aviation medicine. New York: CRC Press, 2006. Print. Robinson, D. Human being pilot; human factors for aviation professionals. Cheltenham: Aviation Theory Center, 2008. Print. Read More