Postmortem absorption of drugs and ethanol from aspirated vomitus--an experimental model.

Using human cadavers an experimental model was developed to simulate the agonal aspiration of drug- and alcohol-laden vomitus. By needle puncture, an acidified (N/20 HCl) 60-ml slurry of drugs (paracetamol 3.25 g, dextropropoxyphene 325 mg) and ethanol 3% w/v was introduced into the trachea. After 48 h undisturbed at room temperature, blood samples were obtained from ten sites. Ethanol and drug concentrations were highest in the pulmonary vessels in all five cases studied. Pulmonary vein mean ethanol was 58 mg% (range 13-130), paracetamol 969 mg/l (range 284-1934), propoxyphene 70 mg/l (range 11-168). Pulmonary artery mean ethanol was 53 mg% (range 10-98), paracetamol 476 mg/l (range 141-882), propoxyphene 29 mg/l (range 7.6-80). Ethanol and drug concentrations in aortic blood were higher than in the left heart and concentrations in the superior vena cava were higher than in the right heart, suggesting direct diffusion into these vessels rather than diffusion via the pulmonary and cardiac blood. Potential interpretive problems arising from this phenomenon can be avoided by using femoral vein blood for quantitative toxicological analysis.     

Concentrations of zolpidem and zopiclone in venous blood samples from impaired drivers compared with femoral blood from forensic autopsies

The concentrations of zolpidem and zopiclone were determined in peripheral blood samples in two forensic materials collected over a 10-year period (2001-2010). The z-hypnotics were determined in venous blood from living subjects (impaired drivers) and in femoral blood from deceased persons (forensic autopsies), with the latter classified as intoxication or other causes of death. The z-hypnotics were determined in blood by capillary column gas chromatography (GC) with a nitrogen-phosphorous (N-P) detector after solvent extraction with n-butyl acetate. The analytical limit of quantitation (LOQ) was 0.02mg/L for zopiclone and 0.05mg/L for zolpidem and these have remained unchanged throughout the study. When death was attributed to drug intoxication (N=918), the median concentration of zopiclone in blood was 0.20mg/L compared with 0.06mg/L for other causes of death (N=1215) and 0.07mg/L in traffic offenders (N=691) (p<0.001). Likewise, a higher median concentration (0.30mg/L) was found in intoxication deaths involving zolpidem (N=357) compared with 0.13mg/L for other causes of death (N=397) or 0.19mg/L in impaired drivers (N=837) (p<0.001). Median concentration in blood of both z-hypnotics were appreciably higher in intoxication deaths when no other substances were identified; 0 70mg/L (N=12) for zopiclone and 1.35mg/L (N=12) for zolpidem. The median concentrations of z-hypnotics in blood decreased as the number of co-ingested substances increased for intoxication deaths but not other causes of death. The most prevalent co-ingested substances were ethanol in autopsy cases and diazepam in the motorists. This large compilation of forensic cases should prove useful when toxicologists are required to interpret concentrations of z-hypnotics in blood samples in relation to cause of death.     

Postmortem toxicology of drugs of abuse

Conducting toxicology on post-mortem specimens provides a number of very significant challenges to the scientist. The range of additional specimens include tissues such as decomposing blood and other tissues, hair, muscle, fat, lung, and even larvae feeding on the host require special techniques to isolate a foreign substance and allow detection without interference from the matrix. A number of drugs of abuse are unstable in the post-mortem environment that requires careful consideration when trying to interpret their significance. Heroin, morphine glucuronides, cocaine and the benzodiazepines are particularly prone to degradation. Moreover, redistributive process can significantly alter the concentration of drugs, particularly those with a higher tissue concentration than the surrounding blood. The designer amphetamines, methadone and other potent opioids will increase their concentration in blood post-mortem. These processes together with the development of tolerance means that no concentration of a drug of abuse can be interpreted in isolation without a thorough examination of the relevant circumstances and after the conduct of a post-mortem to eliminate or corroborate relevant factors that could impact on the drug concentration and the possible effect of a substance on the body. This article reviews particular toxicological issues associated with the more common drugs of abuse such as the amphetamines, cannabinoids, cocaine, opioids and the benzodiazepines.     

Stability of drugs in stored postmortem femoral blood and vitreous humor

The stability of 46 drugs in postmortem femoral blood stored for one year at -20 degrees C was investigated. The drugs included benzodiazepines, antidepressants, analgetics and hypnotics. For seven drugs we found a significant change in the concentration between the first and second analysis. Five substances; ethanol, desmethylmianserin, 7-amino-nitrazepam, THC and zopiclone showed a decrease in the concentration whereas the concentrations of two substances; ketobemidone and thioridazine increased. However, the changes observed were not of such an order that it would affect the interpretation in normal forensic casework. We also investigated the possible influence of potassium fluoride on the concentrations of the 46 drugs in vitreous humor after storage for one year. For two substances, ethanol and zopiclone, there were significantly lower concentrations in the samples without potassium fluoride. Furthermore, we also studied the correlation between the concentrations in femoral blood and vitreous humor. For 23 substances there was a significant difference between the concentrations in the vitreous humor and femoral blood. Significant correlations between the concentrations in these two specimens were found for 23 substances, indicating that vitreous humor can be an alternative specimen when blood samples are not available, provided that such correlation exists for the particular substance. Statistical analysis also revealed a correlation between the degree of protein binding of the different drugs and percentage of vitreous/femoral blood concentrations.     

Postmortem redistribution of fentanyl in the rabbit blood

Postmortem redistribution of fentanyl in the rabbit was investigated after application of the 50-μg/h Durogesic pain patch. Patches were applied for 48 hours. Two cycles of patch administration were used before characterization of the postmortem redistribution. Fentanyl showed marked redistribution into the femoral and pulmonary veins of the rabbit through 48 hours after the animals were humanely killed and the pain patches removed. The plasma concentration of 2.34 ng/mL in the femoral blood before killing the animals increased 5.6-fold by 48 hours after patch removal to 13.2 ng/mL. This postmortem concentration is approximately 3-fold the C(max) determined during antemortem pharmacokinetic analysis, 4 ng/mL, which was achieved 24 hours after the application of the second 50-μg/h Durogesic pain patch. After blood sampling for 48 hours after animal termination with patch removal compared with sampling for 48 hours from animals not terminated and with patch removal, the exposure ratios in the terminated animals were approximately 30-fold, indicating that between the postmortem redistribution of fentanyl and the cessation of hepatic clearance of fentanyl in the rabbit, the postmortem redistribution of fentanyl leads to an elevated measures of postmortem blood concentrations relative to antemortem blood concentrations.     

Postmortem stability of barbiturates in blood and tissues

The stability of five commonly prescribed barbiturates and thiopental in blood and liver at room temperature and at 4 degrees C was studied. Gas chromatography was used for oxybarbiturate analysis while liquid chromatography was used to quantitate thiopental. In blood and liver, greater than 75% of the drugs were detected at the end of the two- to three-month period. These changes were not considered significant; therefore, barbiturates appear to be stable in blood and liver under the conditions of these experiments.     

Postmortem assessment of fetal diaphyseal femoral length: validation of a radiographic methodology

Depending on the general condition of fetal remains, forensic specialists might face difficulties concerning age estimation. Reference tables and regression equations are helpful devices in this task, although they are generally applied for complete fetuses or fetal remains including soft tissues. However, the problem of age estimation stays for osseous remains, both for entire bones and ossified parts, since most of the reference tables come from ultrasonographic measurements, which are not easily reproducible on fetal osseous remains. Furthermore, the ultrasonographic measurements contain slight errors in comparison to the real anatomical ones. This study describes a radiographic protocol and a measurement technique that facilitate and improve bone measurements, and therefore, facilitate age estimation, too. A qualitative criterion, namely a clear-cut bony endplate, was defined and tested. Its reliability (repeatability and reproducibility) turned out to be good, showing nonsignificative differences to the threshold of 0.05, with average errors of 0.26 and 0.44 mm respectively. Moreover, concerning the test of eventual size differences between the right and left femurs showed a P value < 0.0001. The test of the qualitative criterion was based on the comparison of the radiographic in situ femur measurements and the radiographic measurements of the same bones after dissection. The results were satisfactory, since an average error of 0.58 mm was obtained, which did not give any significant differences to the threshold of 0.05. It was concluded that this methodology provides an easy and precise new measurement tool for forensic practice, and can allow us to establish some nonultrasonographic tables, which fit our population.     

Postmortem measurements of thyroid hormones in blood and vitreous humor combined with histology.

The aim of this study was to investigate whether clinical reference premortem values can be used to assess postmortem concentrations of thyroxine, triiodothyronine, and thyroid stimulating hormone (TSH), to compare the postmortem concentrations in blood and vitreous humor, and to study the possibility of diagnosing hyperthyroidism by comparing thyroid histologic appearance and postmortem hormone values. Biochemical analyses of free thyroxine (FT4), free triiodothyronine (FT3), and TSH in femoral blood and vitreous humor were made in 38 cases. In 40 cases, the hormones and thyroid histologic appearance were studied; 22 had no significant pathologic changes, and 18 showed focal hyperplasia of the follicular epithelium. A positive correlation was seen between the femoral blood and vitreous humor concentrations of FT4 (R = 0.66) but not between the corresponding concentrations of FT3 and TSH. A positive correlation was also seen between FT3 and FT4 in femoral blood (R = 0.74). In cases with normal thyroid histologic appearance, 58% were found to have FT4 values >24 pmol/L (clinical reference interval 9-24 pmol/L), mean value 27.5 +/- 9.4 pmol/L), which did not differ from the FT4 values in the cases with hyperplasia, 31.6 +/- 15 pmol/L. Only 5% of the T3 measurements in the group with normal histologic appearance were >9 pmol/L (clinical reference interval 3-9 pmol/L). The mean value of FT3 in cases with normal histologic appearance was 3.4 +/- 1.3 pmol/L, and in the group with hyperplasia 8.6 +/- 6.1 pmol/L. The difference was statistically significant P < .005). It is concluded that postmortem values of FT3 and FT4 in femoral blood are fairly comparable to premortem clinical reference values, but the upper normal limit, especially for T4, has to be adjusted upward. Analysis of vitreous humor cannot be used post mortem to assess thyroid function. Histologically, hyperplastic changes correlate well with elevated FT3 in femoral blood.     

吗啡及其代谢物在藏毒致死者体内分布初探

目的采用固相萃取、液相色谱一串联质谱（LC-MS／MS）检验方法,考察吗啡和葡萄糖醛酸吗啡（M3G）在一例体内藏毒致急性死亡者体内分布情况。方法提取死者心血、尿、胃内容物、肝、肾、脑等15种检材,经Waters HLB小柱固相萃取后,C18色谱柱分离,采用电喷雾电离（ESI）、多反应监测模式（MRM）检测目标化合物。结果所建方法在0．0l～101μg／mL浓度范围内线性关系良好,提取回收率大于75％。结果显示总吗啡含量（游离态＋结合态）在胃内容物中最高,其次是尿、‘肾,在心血、胃组织、肺和腺体中居中,脑组织和心脏含量最低。结论本例检验结果验证了胃内容物、尿液和肾脏等是该类中毒案件的理想检材,其分布规律也可作为体内毒品分析实验依据。     

Predicting the Postmortem Submersion Interval for Human Remains Recovered from U.K. Waterways*

Abstract: This article aims to increase accuracy in estimating the postmortem submersion interval (PMSI) for bodies recovered from rivers in the United Kingdom. Data were collected from closed case files, crime scene reports, and autopsy files concerning bodies recovered over a 15‐year period from the River Clyde, Scotland, and the River Mersey and canals in northwest England. One hundred and eighty‐seven cases met the study criteria and were scored by quantifying the overall amount of decomposition observed in each case. Statistical analysis showed that the duration of a body’s submergence in water and the temperatures to which it was exposed, as measured in accumulated degree days (ADD), had a significant effect on the decay process. Further analysis indicated that there were no significant differences in decomposition between the waterways. By combining the data from all study samples, it was possible to produce a single linear regression model for predicting ADD from observed decomposition.     

A micromethod for the isolation of drugs from blood using amberlite XAD-2

The extraction of drugs from small blood samples (1 ml or less) for subsequent quantitative determination is described. Isolation was carried out by adsorption of the drugs to Amberlite XAD-2 resin utilizing a batch procedure that enabled the simultaneous extraction of up to 200 samples in approx. 5 hours. A new desorption technique yielded extracts of high purity that could be used directly for gas chromatographic or radioimmunological determinations, even if hemolyzed or putrid blood was to be examined. The following 26 substances were quantitated after addition to postmortem blood speciments at concentrations of 1-10 microgram/ml: tilidine, diphenhydramine, dibenzepine, imipramine, chlorpromazine, amphetamine, pentazocine, phenacetin, methaqualone, meprobamate, parathion, diazepam, digoxin, beta-methyldigoxin, carbromal, glutethimide, amobarbital, pentobarbital, cyclobarbital, phenobarbital, diphenylhydantoin, carbutamide, tolbutamide, glycodiazin, tolazamide and chlorpropamide. Thereby recoveries of 60-100% could be achieved. The reproducibility of the procedure was satisfactory as demonstrated by coefficients of variation of 3.7-8%.     

Postmortem stability of lung surfactant phospholipids.

The postmortem stability of the main phospholipids of lung surfactant-phosphatidyl choline (PC), phosphatidyl ethanolamine (PE), phosphatidyl inositol (PI), phosphatidyl serine (PS) and sphingomyelin (S) in three different deaths; one caused by fresh-water drowning, one by salt-water drowning, and one from a sodium-pentobarbital overdose has been studied. The drug overdose was considered the control because there was no surfactant involvement. The results show the stability of these kinds of lipids in the first 24 h, with a progressive decrease from 48 h on until 96 h, with a significant correlation to the time of P less than 0.01 in most cases.     

Fluidity of cadaveric blood after sudden death: Part I. Postmortem fibrinolysis and plasma catecholamine level

In rats, fibrinolytic activity and plasma catecholamine levels increased rapidly after death. Postmortem fibrinolysis was affected by the method of sacrifice, but catecholamine level was not always affected. Immediately after death, the plasma adrenalin level was higher than the noradrenalin level, but then adrenalin remained unchanged or tended to decrease while noradrenalin tended to increase gradually with time. In human subjects after rapid death, the plasma catecholamine and fibrinolytic activity levels were high. However, in cases after slow death they were low.     

Postmortem diagnosis of syphilitic aortitis, including serological verification on postmortem blood

304 postmortem blood samples were serologically examined for syphilis at Statens Seruminstitut. Seventy-six percent of the samples were usable and gave clear-cut results (18% positive, 34% negative and 24% borderline). Twenty-four percent were indeterminable. The blood samples originated from 304 medico-legally examined bodies, 301 of whom were autopsied. The indications for the serological examinations were suspicion of syphilitic aortitis (SA) on the basis of the macroscopical appearance of the aorta at the autopsy--or information on earlier syphilis. Ninety-seven cases of SA were verified macro- and microscopically, 53 being lethal. The serological results were positive in half of these 97 cases, negative in 15, borderline in 21 and indeterminable in 12. A little more than half of the 97 cases were known in advance in the nation-wide syphilis index at the State Serum Institute. The variegated findings in the remaining part of the material are discussed. It is concluded that serological examination of postmortem blood may be a valuable adjuvant for the pathologist for the diagnosis of SA and other syphilitic manifestations.     

Isolation of drugs from blood and tissues with XAD-2 bags

Nylon bags containing 2-g portions of Amberlite XAD-2 resin were used for systematic analysis of drugs in biosamples. The procedure requires 10 or less grams of material, two XAD-2 bags, and enables rapid and economical isolation of most common drugs. The method was demonstrated on autopsy blood spiked with 19 of the most common drugs, and was routinely used in cases of fatal and non-fatal poisoning. The eluates were clean and suitable for direct gas chromatographic and ultraviolet spectrophotometric analysis.The procedure used appeared more convenient than XAD-2 column extraction procedures. Classic solvent extraction methods were usually less efficient.     

Postmortem pink teeth. Histochemical identification of the causative pigment

The phenomenon of postmortem pink teeth has been reported in subjects who have died suddenly and unnaturally, and whose bodies have been subsequently exposed to a wet or moist environment. Ground and EDTA-decalcified sections of teeth of 21 corpses exhibiting postmortem pink-stained teeth were investigated for the identification of the responsible pigment. With histochemical methods and ultraviolet microscopy, the causative pigment was identified as undegraded hemoglobin. Staining from hemosiderin, bile and bile-related pigments, and porphyrins was ruled out. However, histochemical techniques are unable to reveal the form in which the hemoglobin occurred. The cause of death or time of death had no observable effect on the staining reactions for hemoglobin in the teeth.