Reference intervals for venous blood gas measurement in a healthy Chinese population

Venous blood gas (VBG) analysis has gained increasing popularity as an alternative to arterial blood gas (ABG) analysis, owing to its lower invasiveness and greater feasibility of sample collection. However, currently available reference intervals may not be applicable to the Chinese population due to regional, ethnic, environmental, and lifestyle differences. Therefore, this study aimed to establish appropriate venous blood gas reference intervals (RI) for the Chinese population from plain areas.

A total of 1189 volunteers (595 males, 594 females, aged 10-97 years) and 149 validation volunteers (94 females, 55 males, aged 10-97 years) with conditions unlikely to influence blood gas and acid-base balance were enrolled. Venous blood samples were collected in syringes and analyzed using an ABL90 blood gas analyzer (Radiometer Pacific Pty. Ltd.). Non-parametric methods were applied to establish VBG reference intervals and parametric methods were applied to pCO₂ reference intervals.

After exclusions, VBG RI was derived from 1189 volunteers: pH 7.282-7.438, partial pressure of carbon dioxide(pCO2) Male 32.8-62.2 mmHg Female 33.2-58.7 mmHg, partial pressure of oxygen(pO2)16.0-74.0 mmHg, sodium 134-148 mmol/L, potassium 3.14-4.55 mmol/L, chloride 99-111 mmol/L, ionized calcium 1.07-1.26 mmol/L, total hemoglobin(THB) Male 10.69-17.5 g/dL Female 10.3-15.9 g/dL. After verification in 149 healthy individuals, all reference intervals showed qualified rates above 92%, supporting their clinical applicability.