Evaluation of the relationship of xylazine and fentanyl blood concentrations among fentanyl-associated fatalities.

INTRODUCTION: Illicit fentanyl and fentanyl-analogs have produced a devastating increase in opioid fatalities in the United States. Increasingly, xylazine has been found in the illicit fentanyl supply. The role of xylazine in fentanyl intoxication remains unclear. We reviewed coroner records to evaluate trends and effects associated with xylazine in fentanyl-related fatalities. METHODS: This is a retrospective cohort study of all deaths reported to the Franklin County Coroner's Office in Ohio from 1 January 2019 to 16 March 2023, in which fentanyl was determined causative or contributory to death. Cases identified as fentanyl-associated fatalities were separated into two groups based on whether or not xylazine was also detected. RESULTS: There were 3,052 fentanyl-related fatalities during the study period. 4.8 percent of these decedents also tested positive for xylazine. There was no meaningful demographic difference between fentanyl-related fatalities in which xylazine was detected versus those without xylazine detected. There was a mean of 726 fentanyl-associated fatalities per year, with a peak of 846 deaths in 2020 and a decline thereafter. The percentage of fentanyl-related fatalities with xylazine detected increased in linear fashion from 2.7 percent in 2019 to 6.6 percent in 2022. The median fentanyl concentration was 17.0 µg/L (inter-quartile range: 7.9, 27.0) in cases with xylazine detected and 10.0 µg/L (inter-quartile range: 5.6, 18.0) without xylazine. The odds of a fentanyl concentration greater than 40 µg/L in cases with xylazine detected was more than twice as great (odds ratio: 2.41; 95 percent confidence interval: 1.58-3.64) than that in cases without xylazine detected. CONCLUSIONS: Postmortem fentanyl concentrations were greater in cases with xylazine detected than those without xylazine detected. Though it is unclear why patients who were exposed to xylazine tolerated higher opioid doses prior to succumbing to death, we postulate that xylazine may act to competitively antagonize some degree of mu-opioid receptor binding by opioids.

Fatal Intoxication by the Novel Cathinone 4-Fluoro-3-methyl-α-PVP.

A 30 year old non-hispanic white male was found unresponsive at his workplace and admitted to the hospital in cardiac arrest. He was pronounced deceased shortly after arrival. At autopsy the pathologist noted a 176 pound, well-nourished, atraumatic, adult male with significant bilateral frothy pulmonary edema (right lung 930 g and left lung 1,130 g), cardiomegaly (430 g), dilated ventricles and slight cerebral edema. Upon completion of the systematic toxicological analysis scope for the Franklin County Coroner's Office Toxicology Laboratory, no known drugs were found. Further review of the gas chromatography--mass spectrometry (GC--MS) full-scan library summary reports showed an unknown peak in both the blood and urine solid phase extracts. An analogue of α-pyrrolidinovalerophenone (α-PVP) was identified, and a GC--MS selected ion monitoring method was developed to identify and quantitate the presence of 4-fluoro-3-methyl-α-PVP. This method quantified the drug at 26 ng/mL in gray top femoral blood, 30 ng/mL in purple top heart blood and 20 ng/mL in red top vitreous humor. Qualitative presence was also observed in the urine but was not detected in the liver. The decedent's cause of death was determined to be due to fluoro-methyl-PVP toxicity and the manner was ruled to be accidental. Investigational follow-up interviews corroborated drug use by the deceased with a preference of research chemicals and synthetic cannabinoids via the internet. No published literature is available currently, and to the author's knowledge this is the first incident of a fatal death solely attributed to this substituted cathinone.

Child Fatalities Due to Heroin/Fentanyl Exposure: What the Case History Missed.

This case report presents three unrelated children found to have heroin and/or fentanyl in their systems after general unknown systematic toxicological analysis (STA). The first case involves an 11-month-old male found unresponsive at their residence. The scene response suggested a potentially unsafe sleeping condition or a sudden unexplained infant death. The second case is a 14-month-old female found unresponsive after eating soft candies, suggesting that a choking related death may have occurred. The third case is a 12-year-old male found unresponsive in bed and foaming from the mouth. Gum was removed from the child's airway, suggesting another choking related death. The STA included a 14-drug category enzyme linked immunosorbant assay (ELISA) screening in whole blood. Cases 1 and 3 were presumptively positive for fentanyl, while Case 2 was presumptively positive for opiates and fentanyl. Reflex confirmation was performed in blood, urine and gastric contents, by solid-phase extraction (SPE) for 12 opiates including morphine and 6-monoacetylmorphine (6MAM) by gas chromatography-mass spectrometry (GC-MS) and for fentanyl, norfentanyl, and novel analogs, by liquid chromatography tandem mass spectrometry (LC-MS-MS). High concentrations of fentanyl and 6MAM in the gastric contents of Case 1, along with the presence of diacetylmorphine, suggested probable enteral ingestion of heroin and fentanyl, separately or in a combined formulation. Interpretation of the toxicology results could not determine a probable route of exposure to heroin/fentanyl in Case 2, however, the cause of death was clearly related to this drug mixture. In Case 3, the presence of acetylfentanyl suggested an illicit fentanyl exposure. The intention of this case report is to demonstrate the need for a STA approach for all non-trauma postmortem cases regardless of case circumstances, age or suspicion of drug use.

Could chest wall rigidity be a factor in rapid death from illicit fentanyl abuse?

BACKGROUND: There has been a significant spike in fentanyl-related deaths from illicit fentanyl supplied via the heroin trade. Past fentanyl access was primarily oral or dermal via prescription fentanyl patch diversion. One factor potentially driving this increase in fatalities is the change in route of administration. Rapid intravenous (IV) fentanyl can produce chest wall rigidity. We evaluated post-mortem fentanyl and norfentanyl concentrations in a recent surge of lethal fentanyl intoxications. METHODS: Fentanyl related deaths from the Franklin County coroner's office from January to September 2015 were identified. Presumptive positive fentanyl results were confirmed by quantitative analysis using liquid chromatography tandem mass spectrometry (LC/MS/MS) and were able to quantify fentanyl, norfentanyl, alfentanyl, and sufentanyl. RESULTS: 48 fentanyl deaths were identified. Mean fentanyl concentrations were 12.5 ng/ml, (range 0.5 ng/ml to >40 ng/ml). Mean norfentanyl concentrations were 1.9 ng/ml (range none detected to 8.3 ng/ml). No appreciable concentrations of norfentanyl could be detected in 20 of 48 cases (42%) and were less than 1 ng/ml in 25 cases (52%). Elevated fentanyl concentrations did not correlate with rises in norfentanyl levels. In several cases fentanyl concentrations were strikingly high (22 ng/ml and 20 ng/ml) with no norfentanyl detected. DISCUSSION: The lack of any measurable norfentanyl in half of our cases suggests a very rapid death, consistent with acute chest rigidity. An alternate explanation could be a dose-related rapid onset of respiratory arrest. Deaths occurred with low levels of fentanyl in the therapeutic range (1-2 ng/ml) in apparent non-naïve opiate abusers. Acute chest wall rigidity is a well-recognized complication in the medical community but unknown within the drug abuse community. The average abuser of illicit opioids may be unaware of the increasing fentanyl content of their illicit opioid purchase. CONCLUSION: In summary we believe sudden onset chest wall rigidity may be a significant and previously unreported factor leading to an increased mortality, from illicit IV fentanyl use. Fentanyl and norfentanyl ratios and concentrations suggest a more rapid onset of death given the finding of fentanyl without norfentanyl in many of the fatalities. Chest wall rigidity may help explain the cause of death in these instances, in contrast to the typical opioid-related overdose deaths. Intravenous heroin users should be educated regarding this potentially fatal complication given the increasingly common substitution and combination with heroin of fentanyl.

Evaluation of four immunoassay screening kits for the detection of benzodiazepines in urine.

The identification of benzodiazepines (BZD) in biological fluids can be a challenging process. The large number of various BZD in pharmaceutical distribution, with similar core structures, and individual metabolic profiles all contribute to a complicated and time-consuming analysis. The purpose of the current study was to evaluate the performance of four commercially available immunoassay urine screening kits for use in a forensic urine analysis testing program. The four kits included the Roche Benzodiazepine Plus KIMS assay, Microgenics CEDIA Benzodiazepine assay, Microgenics CEDIA high sensitivity assay with beta-glucuronidase, and Microgenics DRI reagent ready Benzodiazepine assay. Each kit was evaluated for linearity, precision, accuracy, carryover, reagent specificity, and confirmation rates. BZD reagent specificity was compared by analysis of 55 structurally dissimilar compounds to BZD. Negative responses to all 55 compounds were elicited by all four reagent assays. Cross-reactivity for the assays was demonstrated by detecting 27 structurally similar BZD. In addition, greater than 10,000 randomly collected urine samples were screened at a 200 ng/mL cutoff for each assay. Positive samples were confirmed by gas chromatography-mass spectrometry using a panel of 13 BZD confirmation standards. The Microgenics CEDIA high sensitivity assay demonstrated the highest positive screening rate as well as the highest confirmation rate of the four assays.