Blood CO-Oximetry: Blood CO levels were measured by carboxyhemoglobin (CO-Hb) concentration with a spectrophotometric blood gas analyzer (ABL 700 series, manufactured by Radiometer, Copenhagen, Denmark).

• 血一氧化碳水平测定:用分光光度血气分析仪(丹麦ABL700)测定血中碳氧血红蛋白含量。