Managing High-Altitude Pulmonary Edema with Oxygen Alone: Results of a Randomized Controlled Trial

Abstract

Yanamandra, Uday, Velu Nair, Surinderpal Singh, Amul Gupta, Deepak Mulajkar, Sushma Yanamandra, Konchok Norgais, Ruchira Mukherjee, Vikrant Singh, Srinivasa A. Bhattachar, Sagarika Patyal, and Rajan Grewal. High-altitude pulmonary edema management: Is anything other than oxygen required? Results of a randomized controlled trial. High Alt Med Biol. 17:294-299, 2016.-Treatment strategies for management of high-altitude pulmonary edema (HAPE) are mainly based on the observational studies with only two randomized controlled trials, thus the practice is very heterogeneous and individualized as per the choice of treating physician. To compare the response to different modalities of therapy in patients with HAPE in a randomized controlled manner. We conducted an open-label, randomized noninferiority trial to compare three modalities of therapy (Therapy 1: supplemental O with oral dexamethasone 8 mg q8 hours [n = 42], Therapy 2: supplemental O with sustained release oral nifedipine 20 mg q8 hours [n = 41], and Therapy 3: only supplemental O [n = 50]). Bed rest was mandated in all patients. The study was conducted in a cohort of previously healthy young lowlander males at an altitude of 3500 m. Baseline characteristics of the patients were comparable in the study arms. Complete response was defined as clinical and radiological resolution of features of HAPE, no oxygen dependency, a normal 6-minute walk test (6MWT) on 2 consecutive days, and normal two-dimensional echocardiography. Results were compared by analysis of variance using SPSS version 16.0. There was no statistical difference in duration of therapy to complete response between the three groups (Therapy 1: 8.1 ± 4.0 days, Therapy 2: 6.7 ± 3.9 days, Therapy 3: 6.8 ± 3.2 days; p = 0.15). There were no deaths in any of the groups. We conclude that oxygen and bed rest alone are adequate therapy for HAPE and that adjuvant pharmacotherapy with either dexamethasone or nifedipine does not hasten recovery.

<strong>Early Oxygen Inhalation to Prevent SARS-CoV-2-Induced Acute Respiratory Distress Syndrome</strong>

“…7,8 If they were not treated in time, a systemic alveolar edema will develop, when the effectiveness of high-flow oxygen therapy will be greatly compromised. On the contrary, an early low-flow oxygen inhalation shows a good therapeutic effect, 12 no matter whether the general pulmonary vasoconstriction occurs or not (figure).…”

High-altitude illness: Management approach

“…One randomized clinical trial and one case-control study showed that supplemental oxygen treatment at low flow rates with bed rest is an effective alternative of descent 51 , 52 . Therefore, along with bed rest, use of supplemental oxygen to maintain an oxygen saturation level above 90% is recommended to resolve the symptoms 1 , 10 …”

“…Although one non-randomized, experimental study showed that nifedipine may be helpful for treatment of HAPE, 56 a case-control study and another randomized controlled study in more recent years, showed that nifedipine with supplemental oxygen was not superior to treatment with supplemental oxygen only 52 , 57 . However, based on clinical experience, 30 mg nifedipine twice daily is suggested when oxygen is not available and descent is not possible 10 …”

The Complexity of Diagnosing High-Altitude Pulmonary Edema: A Case Report and Review of the Differential Diagnosis of Greater Than Expected Hypoxemia at Altitude

“…HAPE is initially treated with supplemental oxygen, if available, and rest followed by expeditious descent. Recent evidence showed a 95% success rate in treatment of HAPE at moderate altitude with oxygen and rest alone (Yanamandra et al, 2016). In cases when pulmonary edema does not respond to classic intervention, other etiologies must be considered.…”