Exercise in hypobaric, hyperbaric Exercise in hypobaric, hyperbaric and microgravity environments and microgravity environments

- Mathew Yesudhas.- Mathew Yesudhas.

HYPOBARIC ENVIROMENTHYPOBARIC ENVIROMENT

Contents:Contents:

Introduction Introduction Conditions that exists at altitude.Conditions that exists at altitude. Physiological responses to altitude.Physiological responses to altitude. Performance at altitude.Performance at altitude. Adaptation to altitude.Adaptation to altitude. Physical training and performance.Physical training and performance. Health risks of exposure to altitude.Health risks of exposure to altitude.

Introduction Introduction Physiological conditions when considered to the conditions that Physiological conditions when considered to the conditions that

exist at or near sea level: exist at or near sea level: barometric pressure averages about 760 mmHg; barometric pressure averages about 760 mmHg; partial pressure of oxygen (PO partial pressure of oxygen (PO22) is about 159 mmHg; ) is about 159 mmHg;

normal gravitational force.normal gravitational force.

Although the human body tolerates reasonable fluctuations in these Although the human body tolerates reasonable fluctuations in these conditions, large variations from these values pose special conditions, large variations from these values pose special problems.problems.

This is evident when mountain climbers ascend to higher altitudes, This is evident when mountain climbers ascend to higher altitudes, when divers are exposed to pressurized conditions underwater or when divers are exposed to pressurized conditions underwater or when astronauts are in space.when astronauts are in space.

Any of these situations can seriously impair physical performance Any of these situations can seriously impair physical performance and jeopardize life.and jeopardize life.

Hypobaric environment: Hypobaric environment:

Barometric pressure is reduced at altitude. This situation is referred Barometric pressure is reduced at altitude. This situation is referred to as a hypobaric environment (low atmospheric pressure).to as a hypobaric environment (low atmospheric pressure).

The lower atmospheric pressure also means a lower POThe lower atmospheric pressure also means a lower PO22, which , which limits pulmonary diffusion and oxygen transport to the tissues.limits pulmonary diffusion and oxygen transport to the tissues.

This reduced OThis reduced O22 delivery to the body tissues result in hypoxia. (O delivery to the body tissues result in hypoxia. (O22 deficiency).deficiency).

Conditions that exist at altitude:Conditions that exist at altitude:

1) Atmospheric pressure at altitude1) Atmospheric pressure at altitude

2) Air temperature at altitude2) Air temperature at altitude

3) Solar radiation at altitude3) Solar radiation at altitude

Atmospheric pressure at altitude:Atmospheric pressure at altitude: Air has weight.Air has weight.

The barometric pressure at any place on the earth is related to the The barometric pressure at any place on the earth is related to the weight of the air in the atmosphere above that point.weight of the air in the atmosphere above that point.

E.g. barometric pressure at sea level is approx. 760 mmHg whereas E.g. barometric pressure at sea level is approx. 760 mmHg whereas at summit of Mount Everest it’s only about 250 mmHg.at summit of Mount Everest it’s only about 250 mmHg.

Moreover the barometric pressure on earth does not remain Moreover the barometric pressure on earth does not remain

constant; rather it varies with the changes in climatic conditions, time constant; rather it varies with the changes in climatic conditions, time of the year and the specific site at which the measurement is taken.of the year and the specific site at which the measurement is taken.

Although atmospheric pressure varies, the percentages of the gases Although atmospheric pressure varies, the percentages of the gases of the air that we breathe remain unchanged from sea level to high of the air that we breathe remain unchanged from sea level to high altitude.altitude.

At any elevation air always contains 20.93% of oxygen, 0.03% of At any elevation air always contains 20.93% of oxygen, 0.03% of carbon dioxide and 79.04% of nitrogen.carbon dioxide and 79.04% of nitrogen.

So what changes; are the partial pressures of these gases. So what changes; are the partial pressures of these gases.

Air temperature at altitude:Air temperature at altitude: Air temperature decreases at a rate of about 1Air temperature decreases at a rate of about 100C for every 150 m.C for every 150 m.

The combination of low temperatures and high winds at altitude The combination of low temperatures and high winds at altitude poses a serious risk of cold-related disorders, such as hyperthermia poses a serious risk of cold-related disorders, such as hyperthermia and wind chill injuries.and wind chill injuries.

Because of the cold temperatures at altitude, the absolute humidity Because of the cold temperatures at altitude, the absolute humidity is very low. Cold air holds very little water. Thus even if air is fully is very low. Cold air holds very little water. Thus even if air is fully saturated with water, the amount of water contained in the air is saturated with water, the amount of water contained in the air is small.small.

The very low humidity at altitude promotes dehydration. The large The very low humidity at altitude promotes dehydration. The large amount of body water is lost through respiratory evaporation due to amount of body water is lost through respiratory evaporation due to presence of dry air and increased respiratory rate.presence of dry air and increased respiratory rate.

The dry air also increases evaporative water loss through sweating The dry air also increases evaporative water loss through sweating during exercise at altitude.during exercise at altitude.

Solar radiation at altitude:Solar radiation at altitude:

Intensity of the solar radiation increases at altitude for two reasons:Intensity of the solar radiation increases at altitude for two reasons:

A) You are positioned higher in the atmosphere, the light travels A) You are positioned higher in the atmosphere, the light travels through less of the atmosphere before reaching you. Therefore less through less of the atmosphere before reaching you. Therefore less of sun’s radiation, especially the ultra violet rays, is absorbed by the of sun’s radiation, especially the ultra violet rays, is absorbed by the atmosphere at altitude.atmosphere at altitude.

B) Atmospheric water normally absorbs a substantial amount of B) Atmospheric water normally absorbs a substantial amount of sun’s radiation; the limited water vapor found at altitude also sun’s radiation; the limited water vapor found at altitude also increases your exposure. Solar radiation is further amplified if you increases your exposure. Solar radiation is further amplified if you also exposed to reflective light from snow, which is usually found at also exposed to reflective light from snow, which is usually found at higher elevations. higher elevations.

Physiological responses to altitude:Physiological responses to altitude:

Respiratory responses to altitudeRespiratory responses to altitude

Cardiovascular responses to altitudeCardiovascular responses to altitude

Metabolic adaptations to altitude Metabolic adaptations to altitude

Respiratory responses to altitude:Respiratory responses to altitude:

Pulmonary ventilationPulmonary ventilation

Pulmonary diffusion and oxygen transportPulmonary diffusion and oxygen transport

Gas exchange at the musclesGas exchange at the muscles

Maximal oxygen uptakeMaximal oxygen uptake

Pulmonary ventilationPulmonary ventilation Pulmonary ventilation increases at higher altitude, both at rest and during Pulmonary ventilation increases at higher altitude, both at rest and during

exercise.exercise.

Ventilation increases to bring in a larger volume of air.Ventilation increases to bring in a larger volume of air.

Increased ventilation acts much the same as hyperventilation at sea level.Increased ventilation acts much the same as hyperventilation at sea level.

Amount of CO in the alveoli is reduced. COAmount of CO in the alveoli is reduced. CO22 follows the pressure gradient follows the pressure gradient therefore more COtherefore more CO22 diffuses out of the blood. diffuses out of the blood.

This increased COThis increased CO22 clearance allows blood pH to increase, a condition clearance allows blood pH to increase, a condition known as respiratory alkalosis.known as respiratory alkalosis.

To prevent this condition, the kidneys excrete more bicarbonate ion.To prevent this condition, the kidneys excrete more bicarbonate ion.

Bicarbonate ions buffer the carbonic acid formed from COBicarbonate ions buffer the carbonic acid formed from CO22, this reduction , this reduction in bicarbonate ion concentration reduces the blood’s buffering capacity.in bicarbonate ion concentration reduces the blood’s buffering capacity.

Therefore more acid remains in blood and the alkalosis can be reversed.Therefore more acid remains in blood and the alkalosis can be reversed.

Pulmonary diffusion and oxygen transport:Pulmonary diffusion and oxygen transport:

Under resting conditions, pulmonary diffusion does not limit the Under resting conditions, pulmonary diffusion does not limit the exchange of gases between the alveoli and the blood. exchange of gases between the alveoli and the blood.

If gas exchange were impaired or limited, less oxygen would enter the If gas exchange were impaired or limited, less oxygen would enter the blood thereby lowering the arterial POblood thereby lowering the arterial PO22 than the alveolar PO than the alveolar PO22. .

Instead these values remain about equal. Instead these values remain about equal.

But POBut PO22 at sea level is 159 mmHg; however it decreases at an at sea level is 159 mmHg; however it decreases at an elevation. elevation.

As a result the POAs a result the PO22 within the alveoli and the pulmonary capillaries also within the alveoli and the pulmonary capillaries also decreases. decreases.

Consequently Hb saturation decreases from about 98% at sea level to Consequently Hb saturation decreases from about 98% at sea level to an elevation respectively.an elevation respectively.

Gas exchange at the muscles:Gas exchange at the muscles: At sea level the arterial POAt sea level the arterial PO22 is about 100 mmHg and PO is about 100 mmHg and PO22 in body tissues in body tissues

is about 40 mmHg. Difference or the pressure gradient is 60 mmHg.is about 40 mmHg. Difference or the pressure gradient is 60 mmHg.

At altitude (8000 ft) the arterial POAt altitude (8000 ft) the arterial PO22 decreases to 60 mmHg but PO decreases to 60 mmHg but PO22 in in

body tissues remains same i.e. 40 mmHg. Difference or the pressure body tissues remains same i.e. 40 mmHg. Difference or the pressure gradient is only 20 mmHg.gradient is only 20 mmHg.

This is an almost 70% reduction in the diffusion gradient. This is an almost 70% reduction in the diffusion gradient.

The diffusion gradient is responsible for driving the oxygen from the The diffusion gradient is responsible for driving the oxygen from the blood into the tissues.blood into the tissues.

Thus as level of altitude increases the gas exchange at the muscles Thus as level of altitude increases the gas exchange at the muscles decreases.decreases.

Maximal Oxygen UptakeMaximal Oxygen Uptake Maximal oxygen uptake decreases as altitude increases. Maximal oxygen uptake decreases as altitude increases.

A study by Pugh and coworkers showed that men with VO2 max A study by Pugh and coworkers showed that men with VO2 max values of 50 ml.kg-1.min-1 at sea level would be unable to exercise, values of 50 ml.kg-1.min-1 at sea level would be unable to exercise, or even to move, near the peak of Mount Everest because their VO2 or even to move, near the peak of Mount Everest because their VO2 max values at that altitude would decrease to 5 ml.kg-1.min-1. max values at that altitude would decrease to 5 ml.kg-1.min-1.

Thus, most normal people with sea level VO2 max values below 50 Thus, most normal people with sea level VO2 max values below 50 ml.kg-1.min-1 would not be able to survive without supplemental ml.kg-1.min-1 would not be able to survive without supplemental oxygen at the summit of Mount Everest because their VO2 max at oxygen at the summit of Mount Everest because their VO2 max at such an altitude would be too low to sustain their body tissues.such an altitude would be too low to sustain their body tissues.

Enough oxygen would be consumed only to meet their resting Enough oxygen would be consumed only to meet their resting requirements. requirements.

CARDIOVASCULAR RESPONSES TO CARDIOVASCULAR RESPONSES TO ALTITUDEALTITUDE

Blood volume.Blood volume.

Cardiac output.Cardiac output.

Pulmonary hypertension.Pulmonary hypertension.

Blood volumeBlood volume Within a first few hours of arriving at altitude, a person’s plasma volume begins Within a first few hours of arriving at altitude, a person’s plasma volume begins

to decrease, and it plateaus by the end of the first few weeks. to decrease, and it plateaus by the end of the first few weeks.

This decrease in plasma volume is the result of both respiratory water loss and This decrease in plasma volume is the result of both respiratory water loss and the body’s conscious attempt to reduce plasma volume. the body’s conscious attempt to reduce plasma volume.

The combination of respiratory water loss and the dumping of plasma volume The combination of respiratory water loss and the dumping of plasma volume reduce total plasma volume by up to 25%. reduce total plasma volume by up to 25%.

The result of this plasma loss is an increase in the number of red cells per unit The result of this plasma loss is an increase in the number of red cells per unit of blood, allowing more oxygen to be delivered to the muscles for the given of blood, allowing more oxygen to be delivered to the muscles for the given cardiac output.cardiac output.

This reduction in plasma volume occurs with little or no change in the total red This reduction in plasma volume occurs with little or no change in the total red blood cell count. The diminished plasma volume eventually returns to normal blood cell count. The diminished plasma volume eventually returns to normal level.level.

In addition, continuous exposure to high altitude triggers release of In addition, continuous exposure to high altitude triggers release of erythropoietin. This increases the total number from of red blood cells.erythropoietin. This increases the total number from of red blood cells.

These adaptations ultimately result in a greater total blood volume and These adaptations ultimately result in a greater total blood volume and allowing to compensate for the lower POallowing to compensate for the lower PO22 experienced at altitude. experienced at altitude.

Cardiac outputCardiac output

The amount of OThe amount of O22 delivered to the muscles by a given volume of delivered to the muscles by a given volume of blood is limited at altitude because the reduced POblood is limited at altitude because the reduced PO22 causes a causes a reduced diffusion gradient. reduced diffusion gradient.

To compensate for this is to increase the volume of blood delivered To compensate for this is to increase the volume of blood delivered to the active muscles.to the active muscles.

At rest and sub maximal exercise, this is accomplished by At rest and sub maximal exercise, this is accomplished by increasing the cardiac output.increasing the cardiac output.

CARDIAC OUTPUT = STROKE VOLUME X HEART RATE.CARDIAC OUTPUT = STROKE VOLUME X HEART RATE.

During sub maximal exercises for first few hours at altitude, stroke During sub maximal exercises for first few hours at altitude, stroke volume is decreased, and heart rate is increased to compensate this volume is decreased, and heart rate is increased to compensate this reduced stroke volume thus increasing the cardiac output.reduced stroke volume thus increasing the cardiac output.

During maximal ex’s: both heart rate and stroke volume is reduced. During maximal ex’s: both heart rate and stroke volume is reduced. Stroke volume is due to decreased plasma volume and decreased Stroke volume is due to decreased plasma volume and decreased heart rate is due to decrease in response to sympathetic nervous heart rate is due to decrease in response to sympathetic nervous activity. Thus cardiac output is decreased.activity. Thus cardiac output is decreased.

Pulmonary hypertension Pulmonary hypertension

Blood pressure in the pulmonary arteries is increased during exercise at Blood pressure in the pulmonary arteries is increased during exercise at altitude. altitude.

Observed in both acclimatized and unacclimatized subjects.Observed in both acclimatized and unacclimatized subjects.

The cause is unknown and is presumed due to the structural changes in The cause is unknown and is presumed due to the structural changes in pulmonary arteries.pulmonary arteries.

Pulmonary diffusion is not greatly affected at altitude due to increased Pulmonary diffusion is not greatly affected at altitude due to increased pulmonary artery blood pressure and increased ventilation, which allows pulmonary artery blood pressure and increased ventilation, which allows greater blood flow to the upper regions of the lung.greater blood flow to the upper regions of the lung.

Metabolic adaptations to altitude Metabolic adaptations to altitude

At altitude conditions are hypoxic, therefore anaerobic metabolism At altitude conditions are hypoxic, therefore anaerobic metabolism will increase to meet the body’s energy demands because oxidation will increase to meet the body’s energy demands because oxidation would be limited.would be limited.

If this occurs, lactic acid production will increase at any given rate of If this occurs, lactic acid production will increase at any given rate of work above lactate threshold. This is in fact the case except for work above lactate threshold. This is in fact the case except for maximal ex’s.maximal ex’s.

To date there is no conclusive explanation why a lower lactate To date there is no conclusive explanation why a lower lactate concentration occurs during maximal ex’s.concentration occurs during maximal ex’s.

Performance at altitude:Performance at altitude:Endurance activity:Endurance activity: Activities of longer duration demands oxygen and anaerobic energy Activities of longer duration demands oxygen and anaerobic energy

system. This is severely affected at altitude. At the summit of Mount system. This is severely affected at altitude. At the summit of Mount Everest; VOEverest; VO22 max is reduced to 10% to 25% of its value at sea level. max is reduced to 10% to 25% of its value at sea level.

This severely limits the body’s ex’s capacity.This severely limits the body’s ex’s capacity.

Anaerobic sprinting, jumping and throwing activities:Anaerobic sprinting, jumping and throwing activities: Anaerobic sprints that last for less than a minute (swimming sprint) are Anaerobic sprints that last for less than a minute (swimming sprint) are

generally not impaired by moderate altitude and can be improved.generally not impaired by moderate altitude and can be improved. Such activities demands minimal oxygen transport and aerobic Such activities demands minimal oxygen transport and aerobic

metabolism.metabolism. Instead most of the energy is supplied via ATP, phosphocreatine and Instead most of the energy is supplied via ATP, phosphocreatine and

glycolytic systems.glycolytic systems. In addition the thinner air at altitude provides less aerodynamic In addition the thinner air at altitude provides less aerodynamic

resistance.resistance.

Exhaustive activities:Exhaustive activities: These kind of ex’s produces lower lactate levels in blood and muscles These kind of ex’s produces lower lactate levels in blood and muscles

than ex’s performed at sea level.than ex’s performed at sea level.

Acclimatization: Prolong exposure at altitudeAcclimatization: Prolong exposure at altitude

When people are exposed to altitude for days and weeks, their When people are exposed to altitude for days and weeks, their bodies gradually adjust to the lower oxygen tension in the air.bodies gradually adjust to the lower oxygen tension in the air.

Endurance trained athletes who live at altitude for years never attain Endurance trained athletes who live at altitude for years never attain the level of performance that they might achieve.the level of performance that they might achieve.

Following are the sections of adaptation examined on:Following are the sections of adaptation examined on: a) Blood adaptationsa) Blood adaptations b) Muscle adaptationsb) Muscle adaptations c) Cardiorespiratory adaptationsc) Cardiorespiratory adaptations

Blood adaptationsBlood adaptations

During the first weeks at altitude, the number of circulatory During the first weeks at altitude, the number of circulatory erythrocytes increases.erythrocytes increases.

The lack of oxygen stimulates the release of erythropoietin. The lack of oxygen stimulates the release of erythropoietin.

Within the first 3 hrs after the athlete arrives at a high elevation, the Within the first 3 hrs after the athlete arrives at a high elevation, the blood’s erythropoietin concentration increases, reaching a maximum blood’s erythropoietin concentration increases, reaching a maximum within 24 to 48 hrs.within 24 to 48 hrs.

Prolong exposure of around 6 months and more the blood volume Prolong exposure of around 6 months and more the blood volume increases to about 9% to 10%increases to about 9% to 10%

Muscle adaptationsMuscle adaptations

Prolong exposure causes a loss of appetite and a significant weight Prolong exposure causes a loss of appetite and a significant weight loss. loss. This loss represents a general decrease in body weight and This loss represents a general decrease in body weight and extracellular water; thus resulting in decrease in muscle mass.extracellular water; thus resulting in decrease in muscle mass.

ParameterParameter ChangeChange

Muscle areaMuscle area DecreasedDecreased

Slow twitch fiber areaSlow twitch fiber area DecreasedDecreased

Fast twitch fiber areaFast twitch fiber area DecreasedDecreased

Capillary densityCapillary density IncreasedIncreased

Cardiorespiratory adaptationsCardiorespiratory adaptations

One of the important adaptations to altitude is an increase in One of the important adaptations to altitude is an increase in pulmonary ventilation, both at rest and during ex’s.pulmonary ventilation, both at rest and during ex’s.

Ventilation can increases by 50% at rest and during submaximal Ventilation can increases by 50% at rest and during submaximal ex’s.ex’s.

Hyperventilation also promotes respiratory alkalosis, thus to prevent Hyperventilation also promotes respiratory alkalosis, thus to prevent this condition the amount of blood bicarbonate decreases rapidly this condition the amount of blood bicarbonate decreases rapidly during first few days at altitude and remains depressed throughout during first few days at altitude and remains depressed throughout the stay at high elevations.the stay at high elevations.

Physical training and performance:Physical training and performance:

Altitude training for sea level performanceAltitude training for sea level performance

Training for performance at altitudeTraining for performance at altitude

Altitude training for sea level Altitude training for sea level performanceperformance

Most studies have shown no improvement in sea level performance Most studies have shown no improvement in sea level performance following altitude training.following altitude training.

In few studies where altitude training was found to influence post In few studies where altitude training was found to influence post altitude sea level performance, the subjects were not well trained altitude sea level performance, the subjects were not well trained before going to altitude.before going to altitude.

This made it difficult to determine the improvement solely to training This made it difficult to determine the improvement solely to training of altitude.of altitude.

The conditions at moderate to high altitude often cause athletes to The conditions at moderate to high altitude often cause athletes to dehydrate and lose fat free mass. This causes hindrance to athletes dehydrate and lose fat free mass. This causes hindrance to athletes fitness and their tolerance for intense training.fitness and their tolerance for intense training.

Cont..Cont..

Argument exists for:Argument exists for:

a) altitude training induces hypoxiaa) altitude training induces hypoxia

b) altitude induced increase in RBC and Hb levels b) altitude induced increase in RBC and Hb levels improve oxygen delivery on return to sea levelimprove oxygen delivery on return to sea level

-these changes are transient, lasting several days and -these changes are transient, lasting several days and this will be of great advantage.this will be of great advantage.

Recent studies however have shown that typical training Recent studies however have shown that typical training at altitude does not improve sea level performance more at altitude does not improve sea level performance more than good sea-level training does.than good sea-level training does.

Training for performance at altitudeTraining for performance at altitude Research so far is not conclusive, only it appears to show 3 options:Research so far is not conclusive, only it appears to show 3 options: I: Compete within 24 hr of arrival at altitude as it does not provide much I: Compete within 24 hr of arrival at altitude as it does not provide much

acclimatization, after 24 hr altitude sickness may set in and symptoms acclimatization, after 24 hr altitude sickness may set in and symptoms of dehydration and sleep disturbance may follow.of dehydration and sleep disturbance may follow.

II: to get trained 2 weeks prior to competition, but this to is insufficient II: to get trained 2 weeks prior to competition, but this to is insufficient

period for total acclimatization.period for total acclimatization. III: Several weeks of intense aerobic training at sea level that increases III: Several weeks of intense aerobic training at sea level that increases

the VO2 max, which will let them compete at a lower relative intensity the VO2 max, which will let them compete at a lower relative intensity than those who haven’t prepared in a similar manner.than those who haven’t prepared in a similar manner.

Work capacity is reduced at altitude, therefore when first reaching the Work capacity is reduced at altitude, therefore when first reaching the altitude, athletes should reduce workout intensity to between 60% to altitude, athletes should reduce workout intensity to between 60% to 70% of sea level intensity.70% of sea level intensity.

Later, gradually progressing to full intensity within 10 to 14 days.Later, gradually progressing to full intensity within 10 to 14 days.

Health risk of acute exposure to Health risk of acute exposure to altitude:altitude:

Acute altitude sicknessAcute altitude sickness

High altitude pulmonary edema (HAPE)High altitude pulmonary edema (HAPE)

High altitude cerebral edema (HACE)High altitude cerebral edema (HACE)

Acute altitude sicknessAcute altitude sickness

This is also known as mountain sickness. This is also known as mountain sickness.

Symptoms are: headache, nausea, vomiting, dyspnea and insomnia.Symptoms are: headache, nausea, vomiting, dyspnea and insomnia.

These symptoms develop by 6 to 96 hrs after arriving at altitude.These symptoms develop by 6 to 96 hrs after arriving at altitude.

Another side effect is inability to sleep despite marked fatigue.Another side effect is inability to sleep despite marked fatigue.

Studies revel that interrupted breathing i.e. Studies revel that interrupted breathing i.e. “CHEYNE-STOKE BREATHING”“CHEYNE-STOKE BREATHING” which is characterized by alternate rapid breathing and slow, shallow which is characterized by alternate rapid breathing and slow, shallow breathing with intermittent periods of cessation of breathing.breathing with intermittent periods of cessation of breathing.

Treatment:Treatment: a) Gradual ascent and spending few days at that particular elevation.a) Gradual ascent and spending few days at that particular elevation. b) Ascent of no more than 300 m per day at elevations above 3000 m.b) Ascent of no more than 300 m per day at elevations above 3000 m.

c) 2 drugs to reduce the symptoms: acetazolamide and dexamethasone.c) 2 drugs to reduce the symptoms: acetazolamide and dexamethasone.d) Ultimate treatment is to retreat to lower altitude.d) Ultimate treatment is to retreat to lower altitude.

High altitude pulmonary edema (HAPE)High altitude pulmonary edema (HAPE)

HAPE is accumulation of fluids in lungs.HAPE is accumulation of fluids in lungs.

Life threatening, and its cause is unknown.Life threatening, and its cause is unknown.

More often in children and young adults.More often in children and young adults.

Symptoms: since fluid interferes air movement it leads to shortness Symptoms: since fluid interferes air movement it leads to shortness of breath and excessive fatigue.of breath and excessive fatigue.

Treatment: administering supplemental oxygen and moving the Treatment: administering supplemental oxygen and moving the victim to lower altitude.victim to lower altitude.

High altitude cerebral edema (HACE)High altitude cerebral edema (HACE)

HACE is a rare case in which accumulation of fluid takes with the HACE is a rare case in which accumulation of fluid takes with the cranial cavity.cranial cavity.

Cause is unknown.Cause is unknown.

Symptoms: mental confusion progresses to coma and death.Symptoms: mental confusion progresses to coma and death.

Treatment: administering supplemental oxygen and descend to Treatment: administering supplemental oxygen and descend to lower altitude.lower altitude.

ANY ?.ANY ?.

THANK YOU.THANK YOU.