Injuries due to exposure - Altitude sickness

Altitude sickness

Traveling to high altitudes exposes travelers to increasingly rarefied air and progressively decreasing amounts of oxygen, resulting in declining levels of oxygen in the blood and thus impaired physical and mental performance. The response to high altitudes varies from individual to individual, but most people can operate normally at heights up to 8,000 feet (2,438 meters) above sea level. At altitudes greater than that, the oxygen deficit can begin to cause a condition known as acute mountain sickness (AMS). At elevations over 10,000 feet (3,048 meters), 75 percent of people will experience at least mild AMS symptoms.

Signs and symptoms: (Symptoms of a disease are subjective indications that can be detected by a patient, such as pain or fatigue, while signs are objective indications that can be detected by a doctor, such as temperature or pulse.) The onset of AMS symptoms varies according to the altitude, your rate of ascent, and your individual susceptibility to the disease. A slow ascent is more likely to allow your body to acclimate, by establishing a more rapid spontaneous breathing rate to make up for the decreased oxygen in the atmosphere. Symptoms usually start from 12 to 24 hours after your arrival at altitude and begin to decrease in severity by about your third day at a given elevation.

Mild AMS causes travelers to feel generally unwell. They may also suffer a loss of appetite, headache, lightheadedness, fatigue, breathlessness, rapid heartbeat, nausea, and/or difficulty sleeping. Symptoms tend to be worse at night. Mild AMS does not interfere with normal activities, and symptoms generally subside within two to four days, as the body acclimates.

Severe AMS manifests itself in the form of serious conditions known as high-altitude pulmonary edema (HAPE) or high-altitude cerebral edema (HACE) — the accumulation of excess fluid in the lungs or brain. The symptoms of severe AMS include a gray or pale complexion, a blue tinge to the skin (a condition known as cyanosis), chest tightness or congestion, cough, coughing up blood, difficulty walking, shortness of breath when at rest, withdrawal from social interaction, confusion, and/or decreased consciousness. Severe AMS can be fatal if it's not treated or the victim is not returned to a lower altitude.

Sea level:
* Atmospheric pressure is 765 mmHg (millimeters of mercury, the unit of measure for pressure in gases and liquids).
* Partial pressure of atmospheric oxygen is 160 mmHg.
* Arterial oxygen pressure (PaO2) is 80 to 100 mmHg.
* Arterial carbon dioxide pressure (PaCO2) is 38 to 42 mmHg.
High altitude — 8,000 to 12,000 feet (2,438 to 3,658 meters):
* Commercial aircraft cabin pressure is typically equivalent to the pressure at about 8,000 feet (2,438 meters).
* Altitude sickness is common above 8,000 feet (2,438 meters).
* The availability of oxygen drops to 90 to 65 percent of the amount at sea level.
* Arterial PaO2 is significantly diminished.
* Exercise performance decreases and ventilation (the exchange of air between the lungs and the atmosphere) increases due to lower arterial PaCO2.
Very high altitude — 12,000 to 18,000 feet (3,658 to 5,486 meters):
* Atmospheric pressure is 483 mmHg or less.
* The availability of oxygen drops to 65 to 50 percent of the amount at sea level.
* Arterial PaO2 falls below 60 mmHg.
* Extreme hypoxemia (an abnormally low concentration of oxygen in the blood) may occur during exercise and sleep.
* Severe altitude sickness occurs most commonly in this range.
Extreme altitude — above 18,000 feet (5,486 meters):
* The availability of atmospheric oxygen drops below 50 percent of the amount at sea level.
* Marked hypoxemia, very low PaCO2, and alkalosis (excessive alkalinity of the body fluids) are likely to occur.
* All physiological functions progressively deteriorate.
* No permanent human habitation exists above 20,000 feet (6,096 meters).
Treatment: Responding promptly to signs or symptoms of AMS is essential. It is advisable to call the nearest emergency medical service (EMS) immediately if you or someone traveling with you experience any of the following symptoms:
* Severe breathing problems
* Altered level of alertness
* Coughing up blood
If you cannot count on EMS aid, get the affected individual down to a lower altitude as quickly and as safely as possible and administer oxygen if it's available. Also, keep victims warm and, if they're conscious, be sure they stay well hydrated.

To avoid altitude sickness, it's important to ascend slowly enough to allow time for your body to acclimate. Some people also find it beneficial to take prophylactic medication to help with the acclimatization process and/or to prevent some ill effects. If you plan to travel to a high-altitude location, visit your doctor or a travel clinic before your trip to evaluate your risk of altitude sickness and to obtain prophylactic medication that may prevent or alleviate AMS.

Anybody can be affected by AMS. You are at higher risk if:
* You live at or near sea level and travel to a high altitude.
* You have had AMS before.
* You have pre-existing medical conditions.
* You ascend quickly to a high elevation.
Do not travel to a high-altitude location if you have a heart, lung or blood disorder without consulting your doctor. You may need to travel with supplemental oxygen.

Following these strategies can help to prevent and/or moderate AMS:
* Do not ascend quickly above 8,000 feet.
* If you travel to high altitudes, choose a slow transportation method or walk.
* If you get there by flying, do not overexert yourself or travel still higher for the first 24 hours.
* If you travel above 10,000 feet (3,048 meters), increase your altitude by no more than 1,000 feet (305 meters) per day.
* After every 3,000 feet (914 meters) of elevation gained, take a rest day.
* After daily excursions, return to a lower altitude for the night, if possible.
* Don't go higher if you experience any AMS symptoms; wait for the symptoms to decrease first.
* If your symptoms increase, go down!
* Stay properly hydrated. Drink at least three to four quarts of fluids per day, and be sure to quench your thirst. Make sure to urinate regularly.
* Light activity during the day is better than sleeping, because respiration decreases during sleep, exacerbating AMS symptoms.
* Avoid tobacco, alcohol and depressant drugs (such as barbiturates, tranquilizers, and sleeping pills), all of which worsen AMS symptoms.
* Eat a high-carbohydrate diet while at altitude, but do not overeat.

Read the full article HERE


Accidents Acid reflux After anaesthesia Air Quality Air exchange centre Air hose failure Altitude changes Altitude sickness Ama divers Anaerobic Metabolism Annual renewal Apnea Apnoea Arterial gas embolism Arthroscopic surgery Aurel hygiene BCD Back adjustment Back pain Back treatment Backextensors Badages Bag valve mask Bandaids Barbell back squat Batteries Bench press Blood flow Bone fractures Bouyancy compensators Boyle's Law Boyle\'s Law Bradycardia Brain Breast Cancer Breath Hold Diving Breath hold Breath-hold Breathing Gas Breathing Broken bones Bruising Buoyancy Burnshield CGASA CMAS CO2 Cabin pressure Camera settings Cancer Remission Cancer treatments Cancer Cannabis and diving Cannabis Cape Town Dive Festival Cape Town Carbon dioxide Cardio health Cardiomyopathy Chamber Safety Chamber science Charging batteries Charles' Law Charles\' Law Charles\\\' Law Charles\\\\\\\' Law Charles\\\\\\\\\\\\\\\' Law Chemotherapy Chiropractic Citizen Conservation Cleaning products Coastalexcursion Cold Water Cold care Cold Compressed gas Conservation Contaminants Contaminated air Corals Courtactions Crohns disease Crystal build up Crystallizing hoses Cutaneous decompression DAN Courses DAN Profile DAN Researchers DAN medics DAN report DCI DCS Decompressions sickness DCS theories DCS DEMP DM training DReams Dalton's Law Dalton\'s Law Dalton\\\'s Law Dalton\\\\\\\'s Law Dalton\\\\\\\\\\\\\\\'s Law Deco dives Decompression Illness Decompression Sickness Decompression illsnes Decompression treatment Decompression Diaphragms Diseases Dive Chamber Dive Industry Dive Instruction Dive Instructor Dive Pros Dive Research Dive Training Dive Travel Dive accidents Dive buddies Dive computers Dive excursions Dive gear Dive health Dive medicines Dive medicine Dive operators Dive safety Dive staff Diveleader training Diveleaders Diver Profile Diver infliencers Divers Alert Diving Kids Diving Trauma Diving career Diving emergencies Diving emergency management Diving guidelines Diving injuries Diving suspended Diving Dizziness Domestic Donation Dowels Dr Rob Schneider Drysuit diving Drysuit valves Drysuits EAPs EAP Ear pressure Ear wax Ears injuries Education Electronic Emergency action planning Emergency decompression Emergency plans Emergency underwater Oxygen Recompression Emergency Enviromental Protection Environmental factors Environmental impact Environmental managment Equipment care Evacuations Evacuation Evaluations Exercise Exhaustion Extended divetime Extinguisher Extreme treatments Eye injuries FAQ Failures Fatigue Faulty equipment Fire Coral Fire Safety Firefighting First Aid Equipment First Aid Training First Aid kits Fish Fitness to dive Fitness Flying Francois Burman Free Student cover Free diving Free flow Freedive Training Freediver Freediving performance Gas Density Gas laws Gas mixes GasPerformance Gases Gastoeusophagus Gastric bypass Gastroenterologist Gear Servicing Gordon Hiles HELP HIRA Haemorhoid treatment Hazard Description Hazardous Marine life Hazardous marinelife Health practitioner Heart Attack Heart Health Heart Rate monitor Heart rate Heart Heat stress Helium High temperatures Hip strength Hot Humans Hydrate Hydration Hydrogen Hydroids Hydrostatic pressure Hyperbaric Chamber Hyperbaric research Hypothermia Immine systems In Water Recompression Indemnity form Indian Ocean Indonesia Inert gas Infections Instinct Instruction Instructors Insurance Integrated Physiology International travel International Irritation Joint pain Kidneys Kids scubadiver Labour laws Learning to dive Legal advice Legislation Leukemis Liability Risks Liability releases Liability Life expectancy Lifestyle Live aboard diving Low blood pressure Low pressure deterioration Low volume masks Lung function Lung injuries Lung surgery Lung MOD Maintenance Mammalian Dive Response Mammalian effect Marine Scientists Marine parks Marinelife Master scuba diver Maximum operating depth Medical Q Medical emergencies Medical questionaire Medical statement Middle ear pressure Mike Bartick Military front press Mixed Gas Mono Fins Mooring lines More pressure Motion sickness Muscle pain Mycobacterium marinum Nausea Nautilus Neurological assessments Nitrogen build up Nitrox No-decompression Non-rebreather Mask Normal Air Nosebleeds O2 providers O2 servicing OOxygen maintenance Ocean pollution Open water divers Orbital implants Oronasal mask Oxygen Cylinder Oxygen Units Oxygen deficit Oxygen deicit Oxygen ears Oxygen equipment Oxygen masks Oxygen supply Oxygen therapy Oxygen P J Prinsloo PFI PJP Tech Part 3 Phillipines Photography Pistons Planning Plastic Pneumonia Pneumothorax Pollution Pool Diving Preparation Prepared diver Press Release Professional rights Provider course Pulmanologist Pulmonary Bleb Punture wounds Purge RAID South Africa RCAP Radio communications Range of motion Rashes Rechargeable batteries. Recompression chamber Recompression treatment Recompression Recycle Regulator failure Regulators Regulator Remote areas Renewable Report incidents Rescue training Resume diving Risk Assessments Risk assesments Risk assessment Risk elements Risk management SABS 019 Safety Stop Safety Saturation Diving Save our seas Science Scuba Air Quality Scuba Injury Scuba Instructor Scuba children Scuba dive Scuba health Scubalearners Sealife Shoulder strength Sideplank Signs and Symptoms Skin Bends Skin outbreak Skin rash Snorkeling Snorkels Sodwana Bay South Africa Spinal pain Splits Squeezes Standars Step ups Stroke Sulawesi Supplemental oxygen Surgeries Surgery TRavel safety Tattoes Technical Diving The Bends The truth Thermal Notions Tides Tips and trick Transplants Travel tips Travel Tweezers Unconsciousness Underwater photographer Underwater pho Vaccines Vagus nerve Valsalva manoeuvers Vape Vaping Vasvagal Syncope Venting Volatile fuels Washout treatments Wastewater Water Weakness Weigang Xu West Papua Wetsuit fitting Wetsuits White balance Winter Woman in diving Work of Breathing Wound dressings Wreck dive Wreckdiving Youth diver abrasion air-cushioned alert diver altitude anemia antibiotics antiseptics bandages bent-over barbell rows body art breathing air calories burn cardiovascular checklist chemo port child clearances closed circuit scuba currents cuts dead lift decompression algorithms decongestants dehydration dive injuries dive medicing dive ready child dive reflex dive tribe diver rescue diver training dive diving attraction doctors domestic travel dri-suits dry mucous membranes dry suits dry e-cigarettes ear spaces elearning electrolyte imbalance electroytes emergency action plans emergency assessment equalizing exposure injuries eyes fEMAL DIVERS fire rescue fitnes flexible tubing frediving gas bubble gastric acid health heartburn hospital humidity immersion pulmonary edema (IPE join DAN knee longevity lower stress marine pathogens medical issues medical procedures medical risk assesment mental challenge micro-organisims minor illness mucous membranes nasal steroids nasal nematocysts newdivers nitrogen bubbles off-gassed operating theatre operations orthopeadic outgas pain perforation phillippines physical challenges pinched nerves plasters polyester-TPU polyether-TPU post dive preserve prevention pulmunary barotrauma rebreather mask rebreathers retinal detachment risk areas safety stops saturation scissors scuba equipment scuba single use sinus infections smoking snorkeling. spearfishing stings strength sub-aquatic swimmers ears tattoo care tecnical diver thermal protection training trimix unified standards vision impaired warmers water quality