Evaluation of Therapeutic Methods in High Altitude Pulmonary Edema
EMILIO MARTICORENA, MD, FACC* HERBERT N. HULTGREN, MD, FACC Stanford and Palo Alto, California Lima and La Oroya, Peru
From the Departments of Medicine, Palo Alto Veterans Administration Hospital, Palo Alto and Stanford University School of Medicine, Stanford, California; and the Institute of Andean Biology, San Marcos University, Lima and the Chulec General Hospital, La Oroya, Peru.* This study was supported in part by Veterans Administration Research Funds. Manuscript received November 10, 1977; revised manuscript received August 4, 1978, accepted September 1, 1978. Address for reprints: Herbert N. Hultgren, M.D. Veterans Administration Hospital, 3801 Miranda Avenue, Palo Alto, California 94304.
The effect of treatment with bed rest alone was evaluated in 16 patients with high altitude pulmonary edema of mild to moderate severity at an altitude of 3,750 meters in the Central Peruvian Andes. The results Were compared with those in 20 patients who received conventional therapy including the continuous administration of oxygen and bed rest. A system of grading the severity of high altitude pulmonary edema based on clinical symptoms and signs, radiologic findings and heart rate and respiratory rate was developed. The severity of pulmonary edema as evaluated with the grading system was similar in the •two groups of patients. Treatment With bed rest alone resulted in complete recovery in all •patients over a mean period of 60 hours. NO treatment failure occurred. Similar results were obtained with oxygen therapy combined with bed rest, except that the relief of symptoms was more rapid, the decrease in heart rate and respiratory rate was greater and the recovery period was slightly shorter. High altitude pulmonary edema of mild to moderate severity can be treated successfully with bed rest alone without the administration of oxygen and without moving the patient to a lower altitude. Oxygen therapy is more effective and when available should be used in all cases of high altitude pulmonary edema.
High altitude pulmonary edema occurs in persons who ascend rapidly to altitudes higher than 2,500 meters. 1,2 Recent studies 3 indicated that the incidence rate of pulmonary edema after an ascent to 3,750 meters is approximately 0.6 percent in persons over 20 years of age and 2.5 percent in those under age 20. Severe episodes occurred more frequently in young subjects (73 percent) than in adults (22 percent). Fatalities occur when the condition is not diagnosed correctly, when prompt descent cannot be accomplished or when oxygen is not available. 4,~ The conventional treatment of high altitude pulmonary edema is removal of the patient to a lower altitude, bed rest and the administration of 100 percent oxygen. 6 Many other methods of treatment have been used, including the administration of furosemide, morphine, digitalis and corticosteroids. 7,s,9 These methods have not been evaluated properly because most of the studies lack control data and used treatment by bed rest in addition to the administration of a therapeutic agent. No data are available on the effect of bed rest alone in the treatment of high altitude pulmonary edema. In some circumstances, such as mountaineering, prompt descent may be impossible, difficult or dangerous, and oxygen may not be available. Thus bed rest may be the only method of therapy available until the patient can be evacuated to a lower altitude or oxygen can be supplied. Therefore this study was performed at an altitude of 3,750 meters to compare two methods of treating high altitude pulmonary edema: bed restalone and bed rest combined with the administration of oxygen.
February 1979
The American Journal of CARDIOLOGY
Volume 43
307
HIGH ALTITUDE PULMONARY EDEMA--MARTICORENA ET AL.
TABLE I Severity Classification of High Altitude Pulmonary Edema
Grade 1. Mild 2. Moderate 3. Serious
4. Severe
Minor symptoms with dyspnea on moderate exertion. May be able to perform light activity. Symptoms of dyspnea, weakness, fatigue on slight effort. Cannot perform light activity. Headache with cough, dyspnea at rest. Severe dyspnea, headache, weakness, nausea at rest. Loose recurrent productive cough. Wheezy, difficult respirations with obvious cyanosis.
EMILIO MARTICORENA, MD, FACC* HERBERT N. HULTGREN, MD, FACC Stanford and Palo Alto, California Lima and La Oroya, Peru
From the Departments of Medicine, Palo Alto Veterans Administration Hospital, Palo Alto and Stanford University School of Medicine, Stanford, California; and the Institute of Andean Biology, San Marcos University, Lima and the Chulec General Hospital, La Oroya, Peru.* This study was supported in part by Veterans Administration Research Funds. Manuscript received November 10, 1977; revised manuscript received August 4, 1978, accepted September 1, 1978. Address for reprints: Herbert N. Hultgren, M.D. Veterans Administration Hospital, 3801 Miranda Avenue, Palo Alto, California 94304.
The effect of treatment with bed rest alone was evaluated in 16 patients with high altitude pulmonary edema of mild to moderate severity at an altitude of 3,750 meters in the Central Peruvian Andes. The results Were compared with those in 20 patients who received conventional therapy including the continuous administration of oxygen and bed rest. A system of grading the severity of high altitude pulmonary edema based on clinical symptoms and signs, radiologic findings and heart rate and respiratory rate was developed. The severity of pulmonary edema as evaluated with the grading system was similar in the •two groups of patients. Treatment With bed rest alone resulted in complete recovery in all •patients over a mean period of 60 hours. NO treatment failure occurred. Similar results were obtained with oxygen therapy combined with bed rest, except that the relief of symptoms was more rapid, the decrease in heart rate and respiratory rate was greater and the recovery period was slightly shorter. High altitude pulmonary edema of mild to moderate severity can be treated successfully with bed rest alone without the administration of oxygen and without moving the patient to a lower altitude. Oxygen therapy is more effective and when available should be used in all cases of high altitude pulmonary edema.
High altitude pulmonary edema occurs in persons who ascend rapidly to altitudes higher than 2,500 meters. 1,2 Recent studies 3 indicated that the incidence rate of pulmonary edema after an ascent to 3,750 meters is approximately 0.6 percent in persons over 20 years of age and 2.5 percent in those under age 20. Severe episodes occurred more frequently in young subjects (73 percent) than in adults (22 percent). Fatalities occur when the condition is not diagnosed correctly, when prompt descent cannot be accomplished or when oxygen is not available. 4,~ The conventional treatment of high altitude pulmonary edema is removal of the patient to a lower altitude, bed rest and the administration of 100 percent oxygen. 6 Many other methods of treatment have been used, including the administration of furosemide, morphine, digitalis and corticosteroids. 7,s,9 These methods have not been evaluated properly because most of the studies lack control data and used treatment by bed rest in addition to the administration of a therapeutic agent. No data are available on the effect of bed rest alone in the treatment of high altitude pulmonary edema. In some circumstances, such as mountaineering, prompt descent may be impossible, difficult or dangerous, and oxygen may not be available. Thus bed rest may be the only method of therapy available until the patient can be evacuated to a lower altitude or oxygen can be supplied. Therefore this study was performed at an altitude of 3,750 meters to compare two methods of treating high altitude pulmonary edema: bed restalone and bed rest combined with the administration of oxygen.
February 1979
The American Journal of CARDIOLOGY
Volume 43
307
HIGH ALTITUDE PULMONARY EDEMA--MARTICORENA ET AL.
TABLE I Severity Classification of High Altitude Pulmonary Edema
Grade 1. Mild 2. Moderate 3. Serious
4. Severe
Minor symptoms with dyspnea on moderate exertion. May be able to perform light activity. Symptoms of dyspnea, weakness, fatigue on slight effort. Cannot perform light activity. Headache with cough, dyspnea at rest. Severe dyspnea, headache, weakness, nausea at rest. Loose recurrent productive cough. Wheezy, difficult respirations with obvious cyanosis.
