Obtaining arterial blood gas reference values in an adult population residing at high altitude using CLSIEP28 - A3C standards

Abstract

Introduction: arterial blood gas values are related to geographical location due to oxygen availability and physiological adaptation capacity. Objective: to determine arterial blood gas reference values in a clinically healthy population at 2800 meters above sea level. Method: observational, analytical and cross-sectional study in healthy subjects residing in Quito, attending the Eugenio Espejo hospital, selecting a sample of 264 patients by simple random sampling. The Guide for calculating reference values suggested by the Clinical Laboratory Standards Institute was applied. The data were stored and analyzed in SPSS v18.0. For the calculation of the reference values, the 2,5 and 97,5 percentile were considered as limits of the intervals. Results: mean age was 29,9±5,4 for men and 26,8±6,1 for women (p<0,05). Arterial blood gases showed as results: (pH: men 7,417 (7,387-7,452), women 7.422 (7,391-7,456); PCO2: men 32,5 mmHg (27,3-36,1), women 31,5 mmHg (26,5-35,7); PO2: men 69,6 mmHg (59,6-83,2); HCO3: men 20,4 mEq/L (17,8-22,4), women 20,2 mEq/L (18,0 -21,9)) presented statistically significant differences compared to values at sea level. Conclusions: the values obtained in arterial blood gases in healthy population at sea level compared to those obtained in the city of Quito at 2800 meters above sea level were significantly variable, with PO2 and O2 levels lower than those established at sea level for men and PCO2 and pH for both sexes.

Keywords

• análisis de los gases de la sangre
• estándares de referencia
• valores de referencia
• altitud
• adaptación fisiológica
• ecuador