Understanding High Altitude Illness

Altitude illness, also known as high altitude illness, is a range of medical conditions that occur due to changes in the human body caused by low air pressure and low oxygen levels at high altitudes.

What Causes Altitude Illness?

When you go to high altitudes, several factors can be dangerous, including cold temperatures, ultraviolet (UV) radiation, low air pressure, and low humidity. However, the most significant threat comes from hypoxia, which is when there are low levels of oxygen in the blood. For instance, at 10,000 feet (3,000 meters) above sea level, the oxygen level is only 69% of what it is at sea level.

How Does the Body React?

The body can adapt to moderate levels of low oxygen but needs time to adjust. The severity of hypoxic stress depends on how high you go, how quickly you ascend, and how long you stay at that altitude.

Types of Mountain Sickness

There are three main types of altitude illness:

1.     Acute Mountain Sickness (AMS)

2.     High Altitude Pulmonary Edema (HAPE)

3.     High Altitude Cerebral Edema (HACE)

1.     Acute Mountain Sickness (AMS)

Acute Mountain Sickness (AMS) is the least severe and the most common type of altitude illness. The occurrence of AMS varies significantly, ranging from 9% to 84% in different regions. The symptoms of AMS are similar to those of a hangover from alcohol.

Symptoms of AMS:

• Headache: The primary symptom, usually starting 2 to 12 hours after arriving at a higher altitude or during the first night.
• Fatigue: Feeling unusually tired and lacking energy.
• Loss of Appetite: Not feeling hungry or interested in eating.
• Nausea/Vomiting: Feeling sick to your stomach or vomiting.
• Sleep Disturbances: Difficulty falling asleep or staying asleep.

AMS can affect anyone, regardless of fitness level, and it typically occurs when ascending too quickly without giving the body enough time to adjust. If you experience these symptoms, it is crucial to rest and avoid further ascent until they subside. In most cases, AMS improves within a day or two with proper rest and hydration. If symptoms persist or worsen, descending to a lower altitude is recommended.

Diagnosing Acute Mountain Sickness (AMS)

AMS can be diagnosed using the Lake Louise Consensus Scoring System. This system evaluates the patient's signs and symptoms and their perceived functional limitations to provide a score, which helps diagnose AMS.

Self-Assessment for AMS (S)

(To be filled by the customer themselves in the presence and guidance of the lead guide)

Symptoms	Score
Headache
None	0
Mild	1
Moderate	2
Serve	3
Gastrointestinal
Good appetite	0
Poor appetite and/or nausea	1
Moderate nausea and/or vomiting	2
Serve, incapacitating nausea/vomiting	3
Fatigue and / or Weakness
Not tired or weak	0
Mild fatigue/weakness	1
Moderate fatigue/ weakness	2
Serve fatigue/weakness	3
Dizziness or Light-headedness
None	0
Mild	1
Moderate	2
Serve/incapacitating	3
Difficulty Sleeping
Slept as well as usual	0
Did not sleep as well as usual	1
Woke many times, poor night’s sleep	2
Could not sleep at all	3

Clinical Assessment for AMS (C)

Symptoms	Score
Change in Mental Status
No change	0
Lethargy/Lassitude	1
Semi-consciousness	2
Coma	3
Ataxia (heel/toe walking)
None	0
Balance maneuvers	1
Steps off the line	2
Falls down	3
Unable to stand	4
Peripheral Edema
None	0
One location	1
Two or more locations	2

Functional Score Test for AMS (F)

Symptoms	Score
Effect on Activities
None	0
Mild reduction	1
Moderate reduction	2
Severe reduction: bed rest	3

AMS can be diagnosed if the individual has a headache and meets one of the following criteria:

1. The total self-assessment score (S) is 3 or higher, OR
2. The sum of the total self-assessment score and the total clinical assessment score (S+C) is 5 or higher, OR
3. The sum of all scores (S+C+F) is 6 or higher.

This method ensures a thorough evaluation, enabling accurate diagnosis and appropriate management of AMS.

How can we prevent AMS?

To reduce the risk of AMS, follow these guidelines:

·       Avoid going directly from a low altitude to a sleeping altitude above 9,000 feet (2,750 meters) in one day.

·       Once above 9,000 feet (2,750 meters), limit your daily increase in sleeping altitude to no more than 1,600 feet (500 meters).

·       Plan an extra day for acclimatization for every 3,300 feet (1,000 meters) you ascend.

·       Consider using Acetazolamide (only after consulting your doctor) to speed up acclimatization if an abrupt ascent is unavoidable.

·       Do not consume alcohol for the first 48 hours at high altitudes.

·       Engage in only mild exercise during the first 48 hours at high altitude.

·       Spend two nights or more at an altitude above 9,000 feet (2,750 meters) within 30 days before your trip to help your body adjust.

 

2.     High Altitude Cerebral Edema (HACE)

High Altitude Cerebral Edema (HACE) is a rare but serious form of altitude illness that can be rapidly fatal if not treated promptly. HACE involves swelling of the brain and is an advanced stage of Acute Mountain Sickness (AMS), characterized by neurological symptoms such as ataxia (loss of coordination), confusion, and altered mental status. Immediate descent is crucial for patients with HACE. Failure to descend can result in death within 24 hours of the onset of ataxia.

Treatment for HACE:

1. Immediate Descent: The most important and urgent treatment is to descend to a lower altitude as quickly as possible.
2. If Rapid Descent Is Not Possible:
• Supplemental Oxygen: Administering oxygen can help alleviate symptoms.
• Portable Hyperbaric Chamber (Gamow Bag): This device can simulate lower altitude conditions and provide relief.
• Dexamethasone: This medication can reduce brain swelling.

§  Route of Administration: Oral, Intravenous (IV), or Intramuscular (IM).

§  Dosage: 8 mg initially, followed by 4 mg every 6 hours.

§  Pediatric Dosage: 0.15 mg/kg per dose every 6 hours, up to 4 mg per dose.

3.     High Altitude Pulmonary Edema (HAPE)

High Altitude Pulmonary Edema (HAPE) usually occurs within 24 to 72 hours after ascending to high altitude. It can occur on its own or alongside Acute Mountain Sickness (AMS) or High Altitude Cerebral Edema (HACE). HAPE is characterized by the lungs filling with fluid, leading to serious respiratory issues.

Symptoms of HAPE:

• Early Symptoms:
• Cough
• Decreased exercise tolerance (difficulty performing physical activities)
• Tachypnea (rapid breathing) during exertion
• Progressive Symptoms:
• Tachypnea at rest
• Pink frothy sputum (appears late in the illness)

Treatment for HAPE:

1. Immediate Descent: Descent to a lower altitude with minimal exertion for the patient is crucial.
2. If Rapid Descent Is Not Possible:
• Supplemental Oxygen: Administering oxygen can help alleviate symptoms.
• Portable Hyperbaric Chamber (Gamow Bag): This device can simulate lower altitude conditions and provide relief.
• Nifedipine: This medication can reduce pulmonary pressure.
• Route of Administration: Oral
• Dosage: 30 mg of the sustained-release (SR) version every 12 hours, or 20 mg of the SR version every 8 hours

 

Trust Freedom Adventures for Your Next High-Altitude Adventures

At Freedom Adventures, your safety and satisfaction are our top priorities. Our guides are not only licensed by the government but also hold advanced certifications in wilderness medicine. Our lead guides are certified in Advanced Wilderness First Aid (AWFA), and even our assistant guides are certified in Wilderness First Aid (WFA).

We believe in continuous improvement. Every year, we conduct in-house training sessions to enhance the skills of our team. This ensures that our crew can handle any situation correctly, provide the best customer care, and prevent serious illness and death in high-altitude regions.

With over 20 years of experience in the industry, you can trust Freedom Adventures for your next adventure. We are committed to exceeding your expectations while ensuring your safety throughout your adventure.