Detection of cocaine 24 h after administration before nasotracheal intubation.

BACKGROUND: Cocaine may be applied to decongest the nasal mucosa before nasotracheal intubation, but patients risk a criminal offence if cocaine is detected when patients drive a car shortly after surgery. We aimed to evaluate whether benzoylecgonine levels in saliva exceeded the cut-off point 24 h after administration in patients undergoing nasotracheal intubation and whether cocaine would be detectable above the Danish legal fixed limit in blood samples 1 and 24 h after surgery. METHODS: We conducted a prospective study following approval from the local research ethics committee and the national medicine agency. Written informed consent was obtained from all patients. We included patients scheduled for surgery under general anaesthesia with nasotracheal intubation. They received 80 mg cocaine as a nasal spray 5 min before induction and nasotracheal intubation. The primary outcome was a dichotomous assessment of benzoylecgonine levels in saliva samples measured 24 h after administration of nasal cocaine with a cut-off limit of 200 ng/mL. Secondary outcomes were dichotomous assessments of cocaine in whole blood samples measured 1 and 24 h after administration of nasal cocaine with a cut-off limit of 0.01 mg/kg. RESULTS: Overall, 70 patients had valid saliva samples and 75 had valid blood samples 24 h after cocaine administration. Benzoylecgonine in saliva was traceable above the cut-off in 9/70 patients (13%; CI95%: 6% to 23%), and cocaine in blood was detected above the cut-off in 2/75 patients (3%; CI95%: 0.3% to 9%). CONCLUSION: We found benzoylecgonine traceable in saliva in 13% of patients and cocaine traceable in blood in 3% of patients 24 h after administration of 80 mg nasal cocaine. Patients should be informed when receiving cocaine and advised not to drive for at least 24 h.

Cell injury after ischemia and reperfusion in the porcine kidney evaluated by radiolabelled microspheres, sestamibi, and lactadherin.

BACKGROUND: The purpose of the present study was to quantify renal cell injury after ischemia and reperfusion in a pig model using (99m)Tc-lactadherin as a marker of apoptosis and (99m)Tc-sestamibi as a marker of mitochondrial dysfunction. METHODS: Thirty-four pigs were randomized into unilateral renal warm ischemia of 120 (WI120) or 240 min (WI240). The glomerular filtration rate (GFR) was calculated by renal clearance of (51)Cr-ethylenediaminetetraacetic acid, and apoptosis was quantified by immunohistochemical detection of caspase-3. After 240 min of reperfusion, intravenous (99m)Tc-lactadherin or (99m)Tc-sestamibi was injected simultaneously with (153)Gd microspheres into the aorta. Ex-vivo static planar images of the kidneys were acquired for determination of the differential renal function of tracer distribution using a gamma camera. RESULTS: In WI120, there was no significant difference in the uptake of microspheres in the ischemic and contralateral normal kidney indicating adequate perfusion (uptake in ischemic kidney relative to the sum of uptake in both kidneys; 46% ± 12% and 51% ± 5%). In WI240, the uptake of microspheres was severely reduced in both groups (17% ± 11% and 27% ± 17%). GFR was severely reduced in the post ischemic kidney in both groups. In both groups, the uptake of lactadherin was reduced (41% ± 8%, 17% ± 13%) but not different from the uptake of (153)Gd microspheres. Caspase-3-positive cell profiles were increased in the post-ischemic kidneys (p < 0.001) and increased as the length of ischemia increased (p = 0.003). In both WI120 and WI240, the amount of (99m)Tc-sestamibi in the ischemic kidney was significantly lower than the amount of (153)Gd microspheres (40 ± 5 versus 51 ± 5 and 20 ± 11 versus 27 ± 17; p < 0.05). CONCLUSIONS: In an established pig model with unilateral renal warm ischemia, we found significantly reduced (99m)Tc-sestamibi uptake relative to perfusion in the kidneys exposed to ischemia indicating a potential ability to detect renal ischemic and reperfusion injuries. However, apoptosis was not detected using (99m)Tc-lactadherin in the post-ischemic kidneys despite increased number of caspase-3-positive cell profiles. TRIAL REGISTRATION: This study is approved by the Danish Inspectorate of Animal Experiments (2010/561-1837).

Evaluation of metabolite/drug ratios in blood and urine as a tool for confirmation of a reduced tolerance in methadone-related deaths in Denmark.

BACKGROUND: Methadone blood concentrations in fatal cases are highly variable and there is an appreciable overlap between therapeutic methadone concentrations and the concentrations detected in fatalities. As with other opioids, the background of these methadone-related deaths is unclear. The aim of this study was to investigate if short-time abstinence was contributing to the cause of death in methadone-related deaths by evaluation of the EDDP/methadone ratio in blood and urine. METHODS: Samples of blood and urine were collected from 103 autopsy cases and analysed for the concentrations of methadone and its main metabolite EDDP. The cases were divided into three groups according to the cause of death: cases where methadone was the cause of death (N=67), cases where poly-drug poisoning including methadone was the cause of death (N=24) and cases where death were caused by other factors (N=12). Urine samples from 11 living persons receiving methadone were also included. RESULTS: In general, a substantial overlap of the methadone concentrations in blood and urine was seen between the groups. There was a tendency of lower median EDDP/methadone urinary ratios in the methadone poisoning group (median: 1.0), poly-drug poisoning group (median: 0.94) and in the fatalities not related to methadone (median: 1.1) compared to the living subjects in methadone treatment (median: 1.6), although the differences were not significant. CONCLUSION: It was not possible to reveal a possible abstinence period prior to death by using the EDDP/methadone ratio in blood and urine in methadone-related deaths.

Determination of 19 drugs of abuse and metabolites in whole blood by high-performance liquid chromatography-tandem mass spectrometry.

A high-performance liquid chromatography (LC)-tandem mass spectrometry (MS/MS) method has been developed and validated for the determination of 19 drugs of abuse and metabolites and used in whole blood. The following compounds were included: amphetamine, methylenedioxyamphetamine, methylenedioxyethylamphetamine, methylenedioxymethamphetamine, methamphetamine, cocaine, benzoylecgonine, morphine, 6-acetylmorphine, codeine, methadone, buprenorphine, norbuprenorphine, ketobemidone, tramadol, O-desmethyltramadol, zaleplone, zolpidem, and zopiclone. The sample pretreatment consisted of solid-phase extraction using mixed-mode columns (Isolute Confirm HCX). Deuterated analogues were used as internal standards for all analytes, except for ketobemidone and O-desmethyltramadol. The analytes were separated by a methanol/ammonium formate gradient using high-performance LC (Agilent HPLC 1100) with a 3 mm x 100 mm Varian Pursuit 3 C(18) column, 3-microm particle size, and were quantified by MS/MS (Waters Quattro micro tandem quadrupole mass spectrometer) using multiple reaction monitoring in positive mode. Two transitions were used for all analytes, except for tramadol and O-desmethyltramadol. The run time of the method was 35 min including the equilibration time. For all analytes, responses were linear over the range investigated, with R(2) > 0.99. One-point calibration was found to be adequate by validation, thereby saving analysis of multiple calibrators. The limits of quantification (LOQs) for the analytes ranged from 0.0005 to 0.01 mg/kg. Absolute recoveries of the analytes were from 34 to 97%, except for zaleplone (6%). Both the interday precision and the intraday precision were less than 15% (20% at the LOQ) for all analytes, except buprenorphine, norburprenorphine, and zaleplone (less than 18%). Accuracy (bias) was within +/-15% (+/-20% at the LOQ) for all analytes, except MDMA and O-desmethyltramadol (within +/-19%). No ion suppression or enhancement was seen nor was suppression from coeluted analytes seen. Matrix effects were found to be less than 23% for all analytes, except zopiclone (64%). High-concentration and low-concentration quality control samples gave acceptable values, and the method has been tried in international proficiency test schemes with good results. The present LC-MS/MS method provides a simple, specific, and sensitive solution for the quantification of some of the most frequent drugs of abuse and their metabolites in whole blood. The quantification by LC-MS/MS was successfully applied to 412 forensic cases from October 2008 to mid February 2009, where 267 cases were related to zero-tolerance traffic legislation.

Demonstrating formation of potentially persistent transformation products from the herbicides bromoxynil and ioxynil using liquid chromatography-tandem mass spectrometry (LC-MS/MS).

It is shown that potentially persistent transformation products can be formed from the herbicides bromoxynil (3,5-dibromo-4-hydroxybenzonitrile) and ioxynil (3,5-diiodo-4-hydroxybenzonitrile), and possible leaching to groundwater is discussed. A similar process to the formation of BAM (2,6-dichlorobenzamide) from the herbicide dichlobenil (2,6-dichlorobenzonitrile) can be anticipated as bromoxynil and ioxynil are analogues of dichlobenil and they are degraded by the enzymes nitrilase, nitrile hydratase and amidase. A biodegradation study using cultured Variovorax sp. DSM 11402, a species commonly found in soil, demonstrated that ioxynil and bromoxynil were fully transformed into their corresponding amides in 2-5 days. These amides were not further degraded within 18 days, and formation of other degradation products was not observed. These results are in agreement with biodegradation experiments with dichlobenil. In soil, dichlobenil is transformed into its only observed degradation product BAM, which is persistent and mobile, and has been found in 19% of 5000 samples of Danish groundwater. Variovorax sp. is known to degrade the non-halogenated analogue benzamide, suggesting that degradation of the three amides may be hindered by the halogenated substituents (meta-Br; meta-I; ortho-Cl). This hypothesis is supported by QSAR modelling of fundamental properties. Using a new optimised liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, the sorption and desorption properties of bromoxynil and ioxynil were characterised in sandy topsoil at four concentration levels. The estimated sorption coefficient K(d) was 1.4 L kg(-1) for bromoxynil and 5.4 L kg(-1) for ioxynil, indicating weak to moderate sorption to topsoil. Desorption of the herbicides showed that they were strongly and irreversible bound to the soil (K(des) > K(d)). The amount of herbicide desorbed depended on the initial concentration level. At low levels, K(des) values were higher, indicating stronger binding than at higher levels. The isocratic LC-MS/MS method developed for simultaneous detection of bromoxynil, ioxynil and their main degradation products is described. Using negative electrospray ionisation (ESI-), the detection limits were 0.4-1.0 microg L(-1), with relative standard deviations of 4-10% (n = 10) using direct injection without clean-up steps. The standard curves showed linearity in the range 5-100 microg L(-1) with r(2) > 0.992.