Observational Study on the Incorporation of Opioids and Their Metabolites Into Hair of Pediatric Patients

Hair analysis is a well-established and important tool in both forensic and clinical context. When it comes to the interpretation of positive hair analysis results, reliable and comprehensive reference data is essential. Such data on opioids, especially novel synthetic ones (such as fentanyl and its analogues (fentalogs)) is currently highly limited. This applies especially to hair with pediatric origin, due to differences in the metabolism and hair anatomy in children compared to adults. Investigators hypothesize that opioids, both traditional and novel synthetic ones exhibit detectable concentrations and distinct metabolite ratios within the hair matrices of pediatric patients. Thus, this observational, prospective research study provides 150 hair and sweat samples from children who received opioids as part of surgery or pain management. The samples will be consecutively extracted and analyzed using a sensitive targeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, enabling the quantitative determination of the opioid and metabolite concentrations. The study thereby contributes valuable reference data for both forensic and clinical applications, addressing challenges in interpreting hair analysis results in especially pediatric populations. Further, a deeper understanding of the mechanisms (e.g. via sweat) and pharmacokinetic processes involved in the opioid incorporation to hair will be achieved. The study has received ethical approval from the Swiss Ethics Board (approval number: 2022-01693 / amendment approval date: 09.01.2024).