Nifedipine or other pulmonary vasodilators may be used to treat concurrent HAPE and HACE, but avoid lowering mean arterial pressure, as this may decrease cerebral perfusion pressure and thereby increase the risk for cerebral ischemia. Nifedipine is used for its pulmonary vasodilating effects.
What is the most effective treatment for HAPE?
The most reliable and effective treatment for HAPE is immediate descent of at least 1,000 m (approximately 3,280 ft), supplemental oxygen to achieve an arterial saturation greater than 90%, or both ( 13 ). Descent should be passive since physical exertion will exacerbate likely the patient’s condition.
What is the role of adjunctive pharmacologic therapy in the treatment of HAPE?
If none of the given methods are feasible or available for treating a HAPE patient, adjunctive pharmacologic therapy may be considered but should not be regarded as a substitute for descent or supplemental oxygen. Pharmacotherapy primarily focuses on reduction of pulmonary artery pressure through the use of vasodilators.
When should chemoprophylaxis be initiated for HAPE?
Regardless of which drug is utilized to reduce the risk of HAPE, ideally, any chemoprophylaxis should be initiated on the day prior to ascent and continued until either descent is initiated or the individual has spent 5 d at the target maximum elevation (13).
What is the role of nifedipine in the treatment of HAPE?
Nifedipine or other pulmonary vasodilators may be used to treat concurrent HAPE and HACE, but avoid lowering mean arterial pressure, as this may decrease cerebral perfusion pressure and thereby increase the risk for cerebral ischemia. Nifedipine is used for its pulmonary vasodilating effects.
How do you treat HAPE and HACE?
To treat HACE, you might need a steroid called dexamethasone. If you have HAPE, you will need supplemental oxygen and may need medications, as well as moving to a lower altitude.
What is the best treatment for high altitude pulmonary edema?
Immediate improvement of oxygenation either by supplemental oxygen, hyperbaric treatment, or by rapid descent is the treatment of choice for HAPE.
What are some possible treatments for HACE?
For fluid in the brain (HACE), you may need dexamethasone, a steroid that helps reduce swelling in the brain. Dexamethasone is sometimes prescribed as a preventive medication. For fluid in the lungs (HAPE), you may need oxygen, medication, a lung inhaler or, in severe cases, a respirator.
Which of the following is the most important treatment for all types of high altitude illness?
Slow ascent is the most effective method to prevent altitude illness. Medications for prevention and treatment of acute mountain sickness and high-altitude cerebral edema include acetazolamide and dexamethasone.
How is pulmonary vascular congestion treated?
Pulmonary vascular disease is treated according to its cause. Pulmonary embolism: Blood clots to the lungs are treated with blood thinners (anticoagulation). Treatments include the medicines are betrixaban (BEVYXXA), enoxaparin (Lovenox), heparin, and warfarin (Coumadin).
How does acetazolamide work?
Mechanism of Action Acetazolamide is a carbonic anhydrase inhibitor. That means this drug works to cause an accumulation of carbonic acid by preventing its breakdown. The result is lower blood pH (i.e., more acidic), given the increased carbonic acid, which has a reversible reaction into bicarbonate and a hydrogen ion.
How is high altitude cerebral edema treated?
Dexamethasone is the medication of choice for the treatment of both AMS and HACE. It helps by decreasing cerebral edema. In cases of Severe AMS or HACE, dexamethasone should be used in conjunction with evacuation or while waiting for it.
How common is HAPE and HACE?
About 1% of people of ascend to above 3000m get HACE. The lowest altitude at which a case of HACE has been reported was 2100m. HACE can also occur in people with HAPE and vice versa. Factors that increase the risk of HACE are similar to those for acute mountain sickness and HAPE.
How common is HAPE or HACE?
HACE is a severe medical condition that can be found in 0.5-1% of high-altitude sojourners, usually those suffering from AMS and HAPE.
What is the best medicine for altitude sickness?
Your doctor may recommend dexamethasone to treat altitude sickness. Take it as directed. Take an over-the-counter pain medicine, such as acetaminophen (Tylenol), ibuprofen (Advil, Motrin), or naproxen (Aleve).
What is best for altitude sickness?
Drink twice as much water. One of the best ways to help your body adjust to high altitude is to drink more water. High-altitude areas have low humidity which keeps the air dry, so you should drink twice as much water as you're used to, Dr. Choi says.
Why does acetazolamide help with altitude sickness?
Acetazolamide prevents AMS when taken before ascent; it can also help speed recovery if taken after symptoms have developed. The drug works by acidifying the blood and reducing the respiratory alkalosis associated with high elevations, thus increasing respiration and arterial oxygenation and speeding acclimatization.
How long does high altitude pulmonary edema last?
HAPE occurs 2–4 days after ascent to high altitude, often worsening at night. Decreased exercise performance is the earliest symptom, usually associated with a dry cough.
What happens with high altitude pulmonary edema?
In high-altitude pulmonary edema (HAPE), it's believed that blood vessels in the lungs squeeze together (constrict), increasing pressure. This causes fluid to leak from the blood vessels to the lung tissues and eventually into the air sacs.
How long can you survive with pulmonary edema?
Of the patients needing mechanical ventilation, the in-hospital mortality was 55% (12/22 patients). In-hospital mortality was 12% (18 patients). The median time from the pulmonary oedema event until death was 5 days (range 1–40 days).
What is the survival rate of pulmonary edema?
The Pulmonary Edema Prognostic Score (PEPS) was defined as a sum of all points. Patients with a PEPS of 0 had good short-term prognosis with a 2% in-hospital mortality rate, whereas mortality in patients with a PEPS of 4 was 64%.
What is a HAPE?
Prophylaxis for high-altitude pulmonary edema (HAPE) is indicated for persons who have been identified (from past experience) as being susceptible to developing high-altitude illness or who must ascend rapidly to a high altitude.
Why is acetazolamide considered the drug of choice?
Acetazolamide, which appears to hasten acclimatization, is considered the drug of choice because of a low incidence of significant adverse effects. [ 28] Because acetazolamide hastens acclimatization, it should be effective at preventing all forms of acute altitude illness.
Does dexamethasone reduce pulmonary artery pressure?
The conclusion was that both dexa methasone and tadalafil decrease systolic pulmonary artery pressure and may reduce the incidence of HAPE in adults with a history of HAPE. [ 27] . Dexamethasone prophylaxis may also reduce the incidence of acute mountain sickness in these adults.
Does acetazolamide prevent reentry?
Clinical observations suggest acetazolamide may prevent reentry HAPE, a disorder seen in individuals who reside at high altitude, travel to lower elevation, and then develop HAPE upon rapid return to their homes.
How long does it take for Diamox to acclimate?
If you feel better within two hours of your second Diamox dose, then your body has started to acclimatise. But continue to be on a course of Diamox (250 mg), ever 12 hours for the rest of your trek, starting that night. If you are not feeling better, do not panic. We go to the next level of medication.
What is the most common form of altitude sickness?
AMS is the most common form of altitude sickness we see. It starts off with relatively mild symptoms. But if left untreated, it gets severe and could form into either HAPE or HACE.
How long does it take for Dex to be stopped?
If you still cannot reach lower altitudes after six hours, repeat the same dose and continue your descent. Once you have reached a lower altitude, lower your dosage of Dex to 2 mg, followed by 1 mg every 6 hours. Dex needs to be weaned away and cannot be stopped immediately.
What do you need to carry on a high altitude trek?
You need to carry three absolutely essential Life-Saving Drugs (LSDs) with you on a high altitude trek. It does not matter if you are trekking alone or with a group.
Does Dex help with altitude sickness?
Dex is going to help reduce inflammation in your body that causes these altitude sicknesses. The Diamox and Dex combination will help you sleep better. The next morning, you have to make a decision. If you have slept well and feel better with none of the uneasiness, your body has acclimatised.
Can you take nifedipine with HAPE?
Nifedipine is a drug that reduces your blood pressure. You use it only if you have HAPE. Now let’s see how we can treat altitude sickness i.e. AMS, HAPE and HACE with these LSDs. 1. Let’s start with the easier one, Acute Mountain Sickness (AMS) AMS is the most common form of altitude sickness we see.
Does nifedipine help with HAPE?
Within 30 minutes of the second 10 mg, you should be able to breathe easier. Nifedipine reduces the pressure in your heart and blood vessels. If you remember, I had told you that HAPE occurs because of high pressure around the lungs, when the air sacs start accumulating fluid from your blood.
How to prevent AMS?
Prevention of AMS, HAPE and HACE share some common themes and medications. Both individual predisposition and the speed of ascent can alter the risk for altitude illness. 4 A slow ascent gives time for the body to acclimate. Expert consensus is an ascent in altitude of no more than 1,604 vertical feet (500 m) per day at elevations above 8,202 feet (2,500 m). 1,4 The first camp should be below 9,843 feet (3,000 m). 1 And, the first day at altitude for those who live below 4,921 feet (1,500 m) should be spent at rest. 1
How high does a hace occur?
HACE usually occurs at altitudes above 13,123 feet (4,000 m) and often has very similar symptoms to AMS initially. 1 However, a lack of coordination (ataxia) is a hallmark of HACE and not usually seen in AMS. In the natural course of HACE, coma and death follow lethargy if not treated (ideally with descent).
What is the most common form of altitude sickness?
Altitude illness generally occurs at elevations above 8,000 feet. 1 The condition has a genetic component as well as some degree of variable individual exposure based on underlying medical conditions and fitness level. 2 Acute mountain sickness (AMS) becomes more prevalent as altitude increases and is the most common form of altitude illness. AMS symptoms include headache, general malaise, decreased appetite, fatigue, nausea and vomiting.
What is high altitude pulmonary edema?
High altitude pulmonary edema: Respiratory difficulty that develops during ascent to altitudes above 8,000 feet in otherwise healthy but unacclimatized subjects. Periodic breathing: An abnormal pattern of respiration characterized by alternating periods of apnea and deep, rapid breathing.
What is the total pressure exerted by a gas mixture?
Dalton’s law: The total pressure exerted by a gas mixture is the sum of the individual pressures that created the given volume or gas mixture. High altitude cerebral edema: Neurological impairment that develops during ascent to altitudes above 8,000 feet in otherwise healthy but unacclimatized subjects.
What happens when the oxygen content in the blood drops?
As the oxygen content (PaO 2) and consequently the oxygen saturation (SpO 2) in the arterial blood drops, the brain tells the body to breathe faster. When the body breathes faster, the carbon dioxide (PaCO 2) content also decreases.
How long does it take for the kidneys to remove bicarbonate?
As bicarbonate is removed by the kidneys, the acid-base balance is restored. However, it takes the kidneys days to significantly change the amount of bicarbonate in the blood.
What is a high altitude pulmonary edema?
High-altitude pulmonary edema (HAPE) is a life-threatening, noncardiogenic form of pulmonary edema afflicting certain individuals after rapid ascent to high altitude above 2,500 m (approximately 8,200 ft). HAPE is the most common cause of death related to high altitude.
What are the risk factors for HAPE?
Inadequate acclimatization remains the most significant risk factor for developing HAPE. Clinicians advising individuals, who are preparing to travel to high altitude, should provide education about the importance of making a slow graded ascent. In addition, they should identify the presence of HAPE risk factors and prescribe chemoprophylaxis to those who are at high risk but insist on high-altitude travel. Nifedipine continues to be the prophylactic drug of choice, based on the quality of available clinical evidence and extensive experience with its use. Phosphodiesterase inhibitors, such as tadalafil or sildenafil, are highly promising alternatives, but larger randomized, controlled trials are needed in order to recommend them as primary agents.
What causes HAPE in the lungs?
The presence of conditions or anatomic abnormalities that increase pulmonary blood flow or pressure, including primary pulmonary hypertension, intracardiac shunts such as an atrial septal defect or patent foramen ovale, and congenital absence of a pulmonary artery, also increases the risk of HAPE.
What is the most common cause of death related to high altitude?
HAPE is the most common cause of death related to high altitude. The reported incidence of HAPE ranges from an estimated 0.01% of skiers traveling from low altitude to Vail, CO (2,500 m), to 15.5% of Indian soldiers rapidly transported to altitudes of 3,355 and 5,940 m (approximately 11,000 to 18,000 ft) ( 11 ).
What are the symptoms of HAPE?
Early manifestations of HAPE include decreased exercise tolerance and a prolonged recovery period after exertion at altitude. Dyspnea on exertion, chest discomfort, and dry cough develop, followed by dyspnea at rest as the disease progresses. In severe cases, the cough becomes productive of blood-tinged, frothy sputum.
How high can you climb to prevent hape?
Gradual ascent is therefore the primary recommended method for preventing HAPE. At elevations above 2,500 m (approximately 8,200 ft), sleeping altitudes should be limited to an ascent rate of 300 to 350 m (approximately 1,000 to 1,200 ft) per day. An extra acclimatization day with rest should be added for every 600 to 1,200 m (approximately 2,000 to 4,000 ft) above 2,500 m (approximately 8,200 ft). Pharmacologic prophylaxis is recommended as adjunctive therapy for individuals with a prior history of HAPE and those who must ascend more than 3,000 m (approximately 10,000 ft) in a 24-h period, as may be required in some rescue or military operational scenarios ( 11,24 ).
What is the best treatment for HAPE?
The most effective and reliable treatment of HAPE is immediate descent and administration of supplemental oxygen.
How long does acetazolamide take to work?
For the prophylaxis of altitude illness, start 24-48 hours before ascent and continue for 48 hours after arrival at high altitude. These agents have profound and varied metabolic effects.
What is the drug used to treat HAPE?
These agents are helpful in the prevention of HAPE. Acetazolamide (Diamox) View full drug information. Acetazolamide is used in the prevention of HAPE. It is not used in the treatment of this condition. Acetazolamide promotes renal excretion of bicarbonate, which stimulates respiration.
How high can you climb in a day?
All people ascending to more than 3,500 m in 1 day. All people ascending more than 500 m per day (increase in sleeping elevation) above 3,000 m, without extra days for acclimatization. Very rapid ascents. The CDC recommends the following pharmacologic agents and regimens for HAPE prophylaxis [ 4] :
Is nifedipine effective for pulmonary edema?
Drugs are not as effective as descent from altitude and oxygen in the treatment of high-altitude pulmonary edema (HAPE). Nifedipine, by reducing pulmonary arterial pressure, may be effective in treating HAPE. [ 29] However, in two separate studies, nifedipine did not outperform placebo or oxygen alone. [ 33, 34]
Learning Objectives
Key Terms
- Dalton’s law: The total pressure exerted by a gas mixture is the sum of the individual pressures that created the given volume or gas mixture.
- High altitude cerebral edema:Neurological impairment that develops during ascent to altitudes above 8,000 feet in otherwise healthy but unacclimatized subjects.
- High altitude pulmonary edema: Respiratory difficulty that develops during ascent to altitude…
- Dalton’s law: The total pressure exerted by a gas mixture is the sum of the individual pressures that created the given volume or gas mixture.
- High altitude cerebral edema:Neurological impairment that develops during ascent to altitudes above 8,000 feet in otherwise healthy but unacclimatized subjects.
- High altitude pulmonary edema: Respiratory difficulty that develops during ascent to altitudes above 8,000 feet in otherwise healthy but unacclimatized subjects.
- Periodic breathing: An abnormal pattern of respiration characterized by alternating periods of apnea and deep, rapid breathing.
Getting High
- Altitude illness generally occurs at elevations above 8,000 feet.1 The condition has a genetic component as well as some degree of variable individual exposure based on underlying medical conditions and fitness level.2Acute mountain sickness(AMS) becomes more prevalent as altitude increases and is the most common form of altitude illness. AMS symptoms include headache, g…
Physiology
- To understand altitude illness, one must have a basic understanding of the body’s physiologic response to altitude and its acid-base system. When one ascends in altitude, the amount of oxygen molecules available (partial pressure of oxygen) decreases as the total air pressure decreases, as described in physics by Dalton’s law. This leads to a conflict in the respiratory syst…
Prevention
- Prevention of AMS, HAPE and HACE share some common themes and medications. Both individual predisposition and the speed of ascent can alter the risk for altitude illness.4 A slow ascent gives time for the body to acclimate. Expert consensus is an ascent in altitude of no more than 1,604 vertical feet (500 m) per day at elevations above 8,202 feet (2,500 m).1,4 The first ca…
Treatment
- AMS usually requires no specific treatment. It does require that ascent is stopped until symptoms resolve. This normally takes 12-72 hours. Occasionally, descending 1,640 feet (500 m) to 3,281 feet (1,000 m) is required if symptoms continue to worsen or are severe.1,5 Ensuring proper hydration is essential. Vomiting is a clear impediment to this go...
Conclusion
- Descent is the common treatment for all altitude illness. Under no circumstance should someone suffering from altitude illness be allowed to descend alone. Some patients may be incapacitated to the point that they’re unable to evacuate themselves. These patients should be carried or otherwise moved to a lower elevation and medical care sought without delay.