New strategy for carbon monoxide poisoning diagnosis: Carboxyhemoglobin (COHb) vs Total Blood Carbon Monoxide (TBCO). (January 2020)

• Record Type: Journal Article
• Authors: Oliverio, Stefania; Varlet, Vincent
• Is Part Of: Forensic science international. Volume 306(2020)
• Publication Date: 2020-01
• Subjects: Carbon monoxide poisoning -- Carboxyhemoglobin -- Storage conditions -- Blood analysis -- TBCO -- GC–MS -- COHb; Medical jurisprudence -- Periodicals; Chemistry, Forensic -- Periodicals; Forensic Medicine -- Periodicals; Médecine légale -- Périodiques; Chimie légale -- Périodiques; Gerechtelijke geneeskunde; Gerechtelijke chemie; Gerechtelijke psychiatrie; Chemistry, Forensic; Medical jurisprudence; Electronic journals; Periodicals; Electronic journals; 614.1
• DOI: 10.1016/j.forsciint.2019.110063
• Languages: English
• ISSNs: 0379-0738

Abstract

Highlights: Total blood CO (TBCO) is less affected by storage parameters compared to carboxyhemoglobin (COHb). Correction formula is proposed for analysis in non-optimal storage conditions. Prediction formula was successfully applied for COHb determination from TBCO. TBCO is recommended as alternative biomarker to COHb for CO poisoning diagnosis. Abstract: Diagnosis of carbon monoxide (CO) poisonings has always been a challenging task due to the susceptibility to alterations of the optical state and degradation of blood samples during sampling, transport and storage, which highly affects the analysis with spectrophotometric methods. Methodological improvements are then required urgently because of increased reports of cases with discrepancies between results of the measured biomarker carboxyhemoglobin (COHb) and reported symptoms. Total blood CO (TBCO) measured chromatographically was thus proposed in a previous study as alternative biomarker to COHb. This approach was investigated in this study by comparing the two biomarkers and assessing the effects of various storage parameters (temperature, preservative, time, tube headspace (HS) volume, initial saturation level, freeze- and thaw- and reopening-cycles) over a period of one month. Results show that while for TBCO, concentrations are relatively stable over the observation period regardless of parameters such as temperature, time and HS volume, for COHb, concentrations are altered significantly during storage. Therefore, the use of TBCO as alternative biomarker for CO poisonings has been proposed, since it provides more valid results and is more stable even under non-optimal storage conditions. Additionally, it can be used to predict COHb in cases where sample degradation hinders optical measurement. Furthermore, a correction formula for COHb and TBCO is provided to be used in laboratories or circumstances where optimal storage or analysis is not possible, to obtain more accurate results.