Precision of arterial blood gases and cutaneous oxygen saturation in healthy non-smokers

Abstract

Arterial blood from 20 healthy non-smokers (mean age 36 years) was sampled with a pre-heparinized syringe (Radiometer B129), and analysed with an automatic blood gas analyser (AVL945). Cutaneous oxygen saturation (sO₂) was recorded on an ear oxymeter (Biox IIA). Mean pH±2 SD was 7.392±0.072, mean arterial pCO₂±2 SD was 5.15±0.90 kPa, and mean arterial pO₂±2 SD was 13.68±1.90 kPa. Standard deviation for differences in pairs of analyses (SD) was, for pH 0.008, 0.20 kPa for _PCO₂, and 0.33 kPa for pO₂. In arterial blood from 20 hypoxic patients, SD for pO₂ was 0.10 kPa. Mean cutaneous sO₂±2 SD was 96.7±2.2%, and mean calculated arterial sO₂±2 SD was 97.6±1.0%. Mean arterial pO₂ was higher than that expected from the literature.

Key Words:

• blood gas analysis
• precision
• reference values