title: Validation of a spectrophotometric method for quantification of carboxyhemoglobin.
abstract: The measurement of carboxyhemoglobin (COHb) levels in blood is a valuable procedure to confirm exposure to carbon monoxide (CO) either for forensic or occupational matters. A previously described method using spectrophotometric readings at 420 and 432 nm after reduction of oxyhemoglobin (O(2)Hb) and methemoglobin with sodium hydrosulfite solution leads to an exponential curve. This curve, used with pre-established factors, serves well for lower concentrations (1-7%) or for high concentrations (> 20%) but very rarely for both. The authors have observed that small variations on the previously described factors F1, F2, and F3, obtained from readings for 100% COHb and 100% O(2)Hb, turn into significant changes in COHb% results and propose that these factors should be determined every time COHb is measured by reading CO and O(2) saturated samples. This practice leads to an increase in accuracy and precision.
authors.affiliation: Toxikon Assessoria Toxicologica, São Paulo, Brazil.
authors.forename: Paulo D
authors.initials: PD
authors.lastname: Luchini
authors.forename: Jaime F
authors.initials: JF
authors.lastname: Leyton
authors.forename: Maria de Lourdes C
authors.initials: Mde L
authors.lastname: Strombech
authors.forename: Julio C
authors.initials: JC
authors.lastname: Ponce
authors.forename: Maria das Graças S
authors.initials: Md
authors.lastname: Jesus
authors.forename: Vilma
authors.initials: V
authors.lastname: Leyton
mesh_terms: D002249:Carbon Monoxide Poisoning / Q000175:diagnosis / Q000378:metabolism; D002263:Carboxyhemoglobin / Q000032:analysis* / Q000737:chemistry; D004355:Drug Stability; D053593:Forensic Toxicology / Q000379:methods; D006801:Humans; D008706:Methemoglobin / Q000032:analysis / Q000737:chemistry; D010084:Oxidation-Reduction; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012973:Sodium Hypochlorite / Q000737:chemistry; D013053:Spectrophotometry / Q000379:methods*
chemical_list: D008706:Methemoglobin; D002263:Carboxyhemoglobin; D012973:Sodium Hypochlorite