The Incidence of Subclinical High-altitude Pulmonary Oedema at High Altitude

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01794130
Recruitment Status : Completed
First Posted : February 18, 2013
Last Update Posted : February 18, 2013
Information provided by (Responsible Party):
Institute of Mountain Emergency Medicine

Brief Summary:
The aim of this investigation is to determine the incidence of silent interstitial pulmonary edema by chest ultrasound at moderate altitude (3905m). Secondary endpoints are to detect a suspected association with acute mountain sickness (AMS), co-morbidities and endothelial dysfunction (marker of hypoxia responses, endothelial damage and inflammation).

Condition or disease
Acute Mountain Sickness Subclinical High Altitude Pulmonary Edema

Detailed Description:

The high-altitude pulmonary edema (HAPE) is the leading cause of death from high altitude sickness. At moderate altitude (2500-4500m) the incidence (0.2-6%) may be underestimated because only clinical HAPE leads to symptoms and motivates the patient to seek medical advice. Cremona et al. [Cremona et al. Pulmonary extravascular fluid accumulation in recreational climbers: a prospective study. Lancet 2002;359:303-09] suggested that a silent interstitial pulmonary edema arises in most recreational climbers at moderate altitude. Recently, chest sonography has been shown to effectively detect pulmonary edema and quantify extravascular lung water through the sign of "ultrasound lung comets" (ULCs) originating from water-thickened interlobular septa [Lichtenstein D et al. The comet-tail artifact. An ultrasound sign of alveolar-interstitial syndrome. Am J Respir Crit Care Med;156:1640-46]. The technique requires only basic twodimensional technology and has been applied in extreme, out-of-hospital setting, showing in recreational climbers a high prevalence of clinically silent interstitial pulmonary edema at high-altitude [Pratali L et al. Frequent subclinical high-altitude pulmonary edema detected by chest sonography as ultrasound lung comets in recreational climbers. Crit Care Med 2010;38:1818-23]. However, data for moderate altitude remain scarce, despite that mountaineers are increasing in age and comorbidities and could be more prone to high altitude emergencies.

Prospective, non-randomised, observational study. Study participants are recruited from a scientific research group lead by the Ohio State University during a glaciology study on the Ortles Glacier in South Tyrol (3905m).

Patients are tested for a baseline measure, during a permanent stay on the glacier camp (3h, 9h, 24h, 48h, 72h, 7d ). Parameters include chest ultrasound, Lake Louise score, cerebral sensitive score, non-invasive haemodynamic parameters (i.e. US) and markers of hypoxia responses, endothelial damage and inflammation.

Study Type : Observational
Actual Enrollment : 24 participants
Observational Model: Case-Only
Time Perspective: Prospective
Study Start Date : July 2011
Actual Primary Completion Date : July 2011
Actual Study Completion Date : July 2011

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Edema

Primary Outcome Measures :
  1. Changes in the number of beta-lines in chest sonography [ Time Frame: at 0 (arrival at 3830m), 9, 24, 48 and 72 hours, and at day 7 ]
    as marker of subclinical pulmonary edema

Secondary Outcome Measures :
  1. Changes from baseline of optic nerve sheath diameter [ Time Frame: at 0 (arrival at 3830m), 3, 9, 24, 48 and 72 hours, and at day 7 ]
    evaluated by optical nerve sonography

  2. Changes from baseline in RNA expression in circulating polymorphonucleated [ Time Frame: at 9, 24, 72 hours and day 7 ]

Biospecimen Retention:   Samples With DNA
blood samples

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
Healthy adults

Inclusion Criteria:

  • healthy of age >18y

Exclusion Criteria:

  • cardiac failure
  • chronic kidney disease
  • chronic pulmonary disease
  • acute lung/heart/kidney/brain conditions
  • neoplastic disease
  • lack of consent

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01794130

Institute of Mountain Emergency Medicine, Eurac research
Bolzano, Provincia autonoma di Bolzano, Italy, 39100
Sponsors and Collaborators
Institute of Mountain Emergency Medicine
Study Director: Giacomo Strapazzon, MD Institute of Mountain Emergency Medicine, Eurac research

Responsible Party: Institute of Mountain Emergency Medicine Identifier: NCT01794130     History of Changes
Other Study ID Numbers: V/4/11
First Posted: February 18, 2013    Key Record Dates
Last Update Posted: February 18, 2013
Last Verified: February 2013

Additional relevant MeSH terms:
Altitude Sickness
Pulmonary Edema
Hypertension, Pulmonary
Signs and Symptoms
Respiration Disorders
Respiratory Tract Diseases
Lung Diseases