Determination of carbon monoxide in blood by head space analysis

A method for the determining the amount of carbon monoxide (CO) in blood is described. CO bound to hemoglobin is released with potassium ferricyanide into a known volume of head space of a disposable syringe. Vapor in the head space is withdrawn with a gastight microcyringe and injected into the gas chromatograph. CO dissolved in saturated blood is also measured by head space analysis to ascertain that dissolved CO is able to be removed with only one shaking of blood with nitrogen (N2). N2 put into the head space previously is used as internal standard. The advantages of this method lie in the ease and speed of operation with a simple and widely available instrument.