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When is adaptation complete on ascent to high altitude ?. Gustavo Zubieta-Calleja (Jr) Gustavo Zubieta-Castillo. High Altitude Pathology Institute Clinica IPPA La Paz – Bolivia. www.altitudeclinic.com. The definition of adaptation to high altitude.
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When is adaptation complete on ascent to high altitude ? Gustavo Zubieta-Calleja (Jr) Gustavo Zubieta-Castillo High Altitude Pathology Institute Clinica IPPA La Paz – Bolivia www.altitudeclinic.com
The definition of adaptation to high altitude “The organic systems of human beings and all other species tend to adapt to any environmental change and circumstance, and never tend towards regression which would inevitably lead to death”. Gustavo Zubieta-Castillo Sr.
The High Altitude Adaptation Formula time Adaptation to high altitude = altitude For a fixed altitude, the only significant variable is time. How long does it take to achieve full adaptation to a fixed altitude ?
Macro-systemic Respiratory Increased Ventilation Cardiac Increased Heart Rate Pulmonary Hypertension Micro-systemic Blood oxygen transport Hematocrit increase Increased circulation Neoangiogenesis Cellular changes Increased mitochondrial density Sodium and Potassium pump changes Hydro-balance Neuro-endocrine changes pH correction The Mechanisms of Adaptation to high altitude
Relevant target genes Erythropoyetin Vascular endothelial growth factor (VEGF) Tyrosine hydroxylase Endothelin 1 Genes involved in glucose metabolism Nitric Oxide synthase Transcription factors Hypoxia inducible factor-1 (HIF-1) Activator protein-1 (AP-1) Nuclear factor-IL6 (NF-IL6) Early growth factor (Egf-1) Nuclear factor kappa B (NFkB) The Mechanisms of Adaptation to high altitudeHypoxia induced gene expression
OXYGEN TRANSPORT MECHANISMS . V RR VT RESP. RATE TIDAL VOL. Hb VS HR . STROKE VOL. HEART RATE Q
Full Adaptation Acute Adaptation Intermediate Adaptation Subacute Mountain Sickness CMS AMS
Conclusions Immediate adaptation to high altitude is possible but is not optimal nor definitive. The optimal adaptation is achieved only when the hematocrit reaches the plateau value. This value is specific for each altitude and for each individual. The time lapse depends on the initial hematocrit upon ascent and on the health status.
