Expsr to resdnce or prolonged visit at high altitude, sqla

This code signifies a health condition or symptom that is a direct consequence of a past, prolonged exposure to a high-altitude environment, such as living or extended stays in mountainous regions. The sequela could manifest long after the initial exposure, representing a chronic or delayed effect rather than an acute altitude sickness episode.

Use this code when documenting a patient's current medical condition that is definitively linked to a prior, extended period at high altitude. This applies to conditions like chronic mountain sickness, high-altitude pulmonary hypertension, or other persistent physiological adaptations or damage resulting from such exposure. It should be used when the acute phase of altitude sickness has passed, and the current issue is a lingering effect.

• Always assign this code as a secondary diagnosis, following the code for the specific sequela (e.g., chronic mountain sickness).
• Ensure documentation clearly establishes a causal link between the current condition and the past high-altitude exposure.
• The "S" in the 7th character indicates sequela, meaning the residual effect of a previous injury or disease.