A specific objective supplemental factor in evaluating acute mountain sickness: ΔHR in combination with SaO2

Area of Science:

• Altitude Medicine
• Physiological Responses to Hypoxia

Background:

• Acute mountain sickness (AMS) lacks confirmed diagnostic measurements.
• Objective risk factors for AMS diagnosis are needed.

Purpose of the Study:

• To determine the role of heart rate difference (ΔHR) and oxygen saturation (SaO2) in diagnosing AMS.
• To establish objective risk factors for AMS.

Main Methods:

• 1,019 participants were divided into acute exposure (AEG) and pre-acclimatization (PAG) groups.
• Measurements of resting SaO2 and HR were taken before and after ascent.
• AMS diagnosis was assessed using questionnaires and the Lake Louise Score (LLS).

Main Results:

• AMS incidence was 61.3% in AEG and 38.9% in PAG.
• AMS subjects showed increased HR and decreased SaO2 compared to non-AMS subjects.
• ΔHR and post-exposure SaO2 correlated with LLS; specific thresholds identified as independent risk factors for AMS.

Conclusions:

• ΔHR and SaO2 measurements correlate with AMS severity and diagnosis.
• Combining ΔHR and SaO2 offers a specific, objective method to aid AMS diagnosis.
• These objective markers can improve the confirmation of acute mountain sickness.