Cid-Juárez Silvia, Téllez-Navarrete Norma A, Bautista-Bernal Anaid, León-Gómez Pablo, Salas-Escamilla Isabel, Gochicoa-Rangel Laura, Pérez-Padilla Rogelio
National Institute of Respiratory Diseases (INER), Mexico City, Mexico.
Rev Invest Clin. 2023;75(1):29-36. doi: 10.24875/RIC.22000281.
The values of arterial blood gases (ABG) change with altitude above sea level; empirical verification is essential because ventilatory acclimatization varies with ethnicity and a population's adaptation.
The aim of the study was to describe ABG in a healthy population residing at 2,240 meters above sea level, to identify the mean level of alveolar ventilation (PaCO), and to know whether a progressive increase in PaCO occurs with age and the impact of increasing body mass index (BMI).
We conducted a cross-sectional study in a referral center for respiratory diseases in Mexico City. Associations among variables with correlation coefficient and regression models of PaO, SaO, and P(A-a)O as dependent variables as a function of age, BMI, minute ventilation, or breathing frequency were explored.
Two hundred and seventeen healthy subjects were evaluated with a mean age of 40 ± 15 years, mean of the PaO was 71 ± 6 mmHg, SaO 94% ± 1.6%, PaCO 30.2 ± 3.4 mmHg, HCO 20 ± 2 mmol/L, BE-2.9 ± 1.9 mmol/L, and the value of pH was 7.43 ± 0.02. In a linear regression, the main results were PaO = 77.5-0.16age (p < 0.0001) and with aging P(A-a)O tended to increase 0.12 mmHg/year. PaCO in women increased with age by 0.075 mmHg/year (p = 0.0012, PaCO =26.3 + 0.075age). SaO and PaO decreased significantly in women with higher BMI 0.14% and 0.52 mmHg per kg/m, (p = 0.004 and 0.002 respectively).
Mean PaCO was 30.7 mmHg, implying a mean alveolar ventilation of around 30% above that at sea level.
动脉血气（ABG）值会随着海拔高度的变化而改变；由于通气适应性会因种族和人群的适应情况而有所不同，因此进行实证验证至关重要。
本研究旨在描述居住在海拔2240米处的健康人群的动脉血气情况，确定肺泡通气（PaCO）的平均水平，并了解PaCO是否会随着年龄的增长而逐渐升高以及体重指数（BMI）增加所产生的影响。
我们在墨西哥城一家呼吸系统疾病转诊中心进行了一项横断面研究。探讨了以PaO、SaO和P(A-a)O为因变量，年龄、BMI、分钟通气量或呼吸频率为函数的变量之间的相关性以及回归模型。
对217名健康受试者进行了评估，他们的平均年龄为40±15岁，PaO的平均值为71±6mmHg，SaO为94%±1.6%，PaCO为30.2±3.4mmHg，HCO为20±2mmol/L，BE为-2.9±1.9mmol/L，pH值为7.43±0.02。在线性回归中，主要结果为PaO = 77.5 - 0.16×年龄（p < 0.0001），并且随着年龄增长，P(A-a)O倾向于以每年0.12mmHg的速度增加。女性的PaCO随年龄增长每年增加0.075mmHg（p = 0.0012，PaCO = 26.3 + 0.075×年龄）。BMI较高的女性的SaO和PaO分别显著降低0.14%和每kg/m²降低0.52mmHg（分别为p = 0.004和0.002）。
平均PaCO为30.7mmHg，这意味着平均肺泡通气量比海平面处高出约30%。
