Postmortem production of ethanol in different tissues under controlled experimental conditions

The aim of this study was to follow the postmortem ethanol production phenomenon under controlled experimental conditions (temperature, time interval) in different tissues. Specimens of blood, liver, skeletal muscle and kidney were taken from 30 corpses and no chemical preservatives were used in the specimens collected. Ethanol concentrations were detected by gas chromatography. All specimens stored at -20 degrees C and 4 degrees C did not show any change in ethanol concentration in an eight-day time interval. At 20 degrees C and 30 degrees C, all tissues, except blood, showed statistically significant ethanol production over the time interval tested. However, blood sample kept at 30 degrees C, showed statistically significant increase in ethanol production on the 2nd and 4th day comparing to the controls. Thus, we can state that postmortem ethanol production occurs in different tissues, and is increased at higher temperatures and, in general, it is in accordance with the course of time.     

Potential for error when assessing blood cyanide concentrations in fire victims.

The present study explores toxicologic significance of blood cyanide concentrations in fire victims. Headspace gas chromatography was used for cyanide detection. Analysis of blood samples from ten fire victims (postmortem interval = 8 h to 3 to 5 d) detected zero to 11.9 mg/L of cyanide and a large difference in cyanide concentrations among victims. Carboxyhemoglobin (COHb) saturation was in the range of 24.9 to 84.2%. To examine the effects of methemoglobinemia and postmortem interval on blood cyanide concentrations in fire victims, an experiment was carried out using rabbits as the animal model. The rabbits were sacrificed by intramuscular injection of 1 mL/kg 2% potassium cyanide 5 min after intravenous injection of 0.33 mL/kg of 3% sodium nitrite (Group A, n = 3) or physiological saline (Group B, n = 6). Average methemoglobin contents immediately before potassium cyanide administration were 6.9 and 0.8% in Groups A and B, respectively. Average cyanide concentrations in cardiac blood at the time of death were 47.4 and 3.56 mg/L, respectively. When blood-containing hearts of the rabbits (n = 3 for Group B) were left at 46 degrees C for the first 1 h, at 20 to 25 degrees C for the next 23 h and then at 4 degrees C for 48 h, approximately 85 and 46% of the original amounts of blood cyanide disappeared within 24 h in Groups A and B, respectively. After the 72-h storage period, 37 and 10%, respectively, of the original amounts of cyanide remained in the blood. When the other three hearts in Group B were left at 20 to 25 degrees C for the last 48 h without refrigeration, cyanide had disappeared almost completely by the end of the experiment. The present results and those published in the literature demonstrate that the toxic effects of cyanide on fire victims should not be evaluated based solely on the concentration in blood.     

Postmortem redistribution of digoxin in rats

Adult male Wistar rats were treated with either 0.1 or 3 mg/kg body weight X day of digoxin for five days, then killed and stored at 4 degrees C for 12 h in an attempt to mimic the normal preautopsy procedures in our hospital. In rats treated with 0.1 mg/kg body weight X day, the antemortem serum digoxin concentrations (SDC) were 1.1 +/- 0.4 ng/mL while the 12-h postmortem concentration was markedly increased (16.3 +/- 5.9 ng/mL) (P less than 0.01). In rats treated with 3 mg/kg body weight X day, SDC was not changed significantly (11.2 +/- 4.8 ng/mL antemortem and 13.3 +/- 6 ng/mL postmortem). Postmortem redistribution of digoxin was assessed by injection of 125I-labelled digoxin with or without pretreatment with the unlabelled drug. The results indicate that after death passive redistribution of digoxin may take place. When the SDC are within the therapeutic or low toxic range, digoxin may reenter the blood. High antemortem serum concentrations of digoxin may prevent such passive redistribution. Therefore, antemortem digoxin intoxication cannot be reliably inferred on the basis of high postmortem levels of the drug. Digoxin intoxication can be ruled out when postmortem SDC remain within the therapeutic range. The above changes cast doubt on some of the forensic and cardiologic literature, which has in the past been based on incorrect assumptions concerning postmortem behavior of digoxin.     

Practical experiences with the determination of cadaver age by evaluation of bacterial metabolic products

In an experiment a corpse had been kept at room temperature (16 degrees-23 degrees C) for 1163 h. At regular intervals brain samples were taken and the content of free amino acids and related compounds was determined by column chromatography. It could be demonstrated that in a period of 4-20 days postmortem the age of the corpse could be calculated from the concentrations of alpha-aminobutyrate (ABU), gamma-aminobutyrate (GABA), and glutamic acid (GLU) in brain employing the previously [5] presented formula: (formula; see text) T is the postmortem time lapse (days). ABU, GABA, and GLU are the concentrations (mumol/g) wet tissue of the corresponding amino acids. During this postmortem interval there is nearly a linear correlation; from this interval a correct assignment between concentrations and time cannot be given. The determination method is in the range of about 15 degrees-25 degrees C (guarantees bacterial growth and metabolism) independent of ambient temperature. The brain samples (cortex or parts of the putrified brain mush) can be taken without any special precaution during normal autopsy. The results of the experiment (in Fig. 1) were supported by some practical cases where the time lapse since death was well (in Fig. 1) or reasonably (in Fig. 1) known. These results suggest that this method allows in many cases the determination of the age of a corpse found in a warm environment (approximately 15 degrees-25 degrees C) approximately 4-20 days after death.     

Postmortem redistribution of morphine and its metabolites

The postmortem redistribution of morphine, morphine-3-glucuronide, morphine-6-glucuronide and total morphine was assessed in 40 heroin-related deaths. In blood taken from subclavian, heart, and femoral regions, concentrations of morphine and its metabolites were similar. While there was a trend for higher concentrations in heart blood, when compared with femoral or subclavian blood, this was not significant. There was also no significant difference in concentrations between admission and autopsy blood in which the postmortem interval was on average 59 h. From our observations, significant postmortem redistribution of morphine and its metabolites seems unlikely.     

An Examination of the Postmortem Redistribution of Fentanyl and Interlaboratory Variability,

Fentanyl is a synthetic opioid agonist used for pain control. Often administered as a transdermal patch, it is an interesting drug for study of postmortem redistribution. We hypothesized that fentanyl concentrations would increase over time after death, as measured in blood drawn on the day prior to autopsy and in blood drawn at the time of autopsy in ten cases where fentanyl patches were identified at the scene. Concentrations were compared, and heart blood to femoral blood ratios were calculated as markers of postmortem redistribution. Fentanyl concentrations measured in peripheral blood drawn the day of autopsy (peripheral blood 2 [PB2]) were higher than those drawn the day prior to autopsy (peripheral blood 1 [PB1]) with a mean ratio (PB2/PB1) of 1.80. The ratio of heart blood concentrations (HB) to femoral blood concentrations drawn at autopsy (PB2) had a mean ratio (HB/PB2) of 1.08. Some cases had blood from the same source analyzed at two different laboratories, and concentrations of fentanyl in those samples showed inter‐ and intralaboratory differences up to 25 ng/mL. Postmortem fentanyl concentrations may be affected by antemortem factors, postmortem redistribution, and laboratory variability. Forensic pathologists must use caution in interpreting fentanyl levels as part of death investigation.     

长期饮酒对急性中毒大鼠死后体液内MDMA再分布的影响

目的研究长期饮酒对急性中毒大鼠体液中亚甲基二氧甲基苯丙胺(MDMA)死后再分布的影响。方法 SD雄性大鼠360只,随机均分为A、B、C、D 4组;A、B组以白酒,C、D组以双蒸水为饮用液体,4周后各组按150mg/kg MDMA剂量灌胃,处死后分置于25℃、4℃条件下;以VARIAN CP-3800气相色谱仪分别检测处死时血乙醇含量和0～10d内体液样品中MDMA浓度。结果 0～10d不同条件下,大鼠血液、玻璃体液及尿液中MDMA的PMR浓度变化趋势均为先升高、后降低;各时间点A、B组和C、D组大鼠各体液样本MDMA浓度较0h均有显著性差异(P<0.05),各时间点A与C组、B与D组之间体液样本MDMA浓度有显著性差异(P<0.05);A与B组、C与D组之间体液样本MDMA浓度有显著性差异(P<0.05)。结论长期饮用乙醇会降低MDMA在体液样品中的再分布,其影响程度高低依次为血液、尿液及玻璃体液;低温也可减少体液中MDMA的再分布。     

死后血液流动对氯胺酮在家兔尸体内再分布的影响

目的观察分析静脉注射氯胺酮家兔死后血液流动对体内药物浓度再分布影响。方法雄性新西兰大白兔随机分为实验组2组（各24只）,对照组（8只）;实验组家兔经耳缘静脉注入40mg/kg氯胺酮,1.5h后处死,其中一组立即结扎主动脉,另一组不结扎;家兔尸体仰卧位室温下保存,分别于死后0、3、6、12、24、48、72和96h解剖并采取组织和体液样本;对照组静脉注射等量生理盐水,同样方法解剖取相同样本。所有样本采用GC/MS和GC-NPD法检测样品中氯胺酮含量。结果两个实验组家兔尸体放置96h内氯胺酮含量,除尿液各时间点与0h以及相邻时间点之间比较均有显著性差异（P〈0.05）外,两组家兔其余各类样本与0h以及相邻时间点比较均无显著性差异（P〉0.05）。除尿液外,各类样本两个实验组之间均无显著性差异（P〉0.05）;结扎组和不结扎组心血与外周血中氯胺酮含量比值分别为0.90~1.03和0.90~1.02。结论静脉注射氯胺酮家兔死后的血液流动不是体内氯胺酮发生再分布的主要机制。     

Site-dependent production of gamma-hydroxybutyric acid in the early postmortem period

This study compared endogenous gamma-hydroxybutyric acid (GHB) concentrations in various postmortem fluid samples of 25 autopsy cases. All bodies were stored between 10-20 degrees C until autopsy, and the intervals between death and autopsy were less than 2 days (6-48 h). GHB concentrations were measured by headspace gas chromatography after GHB was converted to gamma-butyrolactone. Endogenous GHB concentrations were significantly higher in femoral venous blood (4.6+/-3.4 microg/ml, n=23) than in cerebrospinal fluid (1.8+/-1.5 microg/ml, n=9), vitreous humor (0.9+/-1.7 microg/ml, n=8), bile (1.0+/-1.1 microg/ml, n=9) and urine (0.6+/-1.2 microg/ml, n=12). GHB concentrations were similar in blood samples taken from different sites. Cut-off limits of 30 and 10 microg/ml are proposed for blood and urine, respectively, to discriminate between exogenous and endogenous GHB in decedents showing no or little putrefaction (postmortem intervals usually 48 h or less). The criterion established for endogenous GHB in postmortem urine may also be applicable to analytical results in cerebrospinal fluid, vitreous humor and bile from deceased persons.     

The extent of postmortem drug redistribution in a rat model.

The aim of this study was to investigate the postmortem redistribution of several drugs in a rat model and to examine if any of the pharmacological properties was related to the extent of this phenomenon. One of the following drugs: phenobarbital (phenobarbitone), acetaminophen (paracetamol), carbamazepine, codeine, verapamil, amphetamine, mianserin, trimeprazine (alimemazine) or chloroquine was administered together with nortriptyline orally to rats 90 min prior to sacrifice. Heart blood was sampled immediately before sacrifice and after 2 h postmortem, as it has previously been shown that this is sufficient time for postmortem concentration changes to occur in heart blood. Blood was also sampled from the clamped abdominal inferior vena cava (representing peripheral blood) and tissue samples were taken from lungs, myocardium, liver, kidney, thigh muscle, forebrain, and vitreous humor together with a specimen from the minced carcass. Drugs were analyzed by high performance liquid or gas chromatography. For phenobarbital, acetaminophen and carbamazepine the postmortem to antemortem blood drug concentration ratios were close to 1.0 and tissue concentrations were low. The postmortem to antemortem heart blood drug concentration ratio for chloroquine (6.9 +/- 1.5) was higher than for nortriptyline (3.5 +/- 0.3), and the remaining drugs (codeine, verapamil, amphetamine, mianserin, and trimeprazine) showed ratios of the same magnitude as nortriptyline. The postmortem to antemortem blood drug concentration ratios for both heart blood and blood from the vena cava and also the lung to antemortem blood drug concentration ratio were closely related to the apparent volume of distribution for the drugs studied (p < 0.001). Accordingly, an apparent volume of distribution of more than 3-4 L/kg is a good predictor that a drug is liable to undergo postmortem redistribution with significant increments in blood levels. The postmortem drug concentration in blood from vena cava was closely related to the antemortem blood level, confirming that among the postmortem samples, the peripheral blood sample was the most representative for the antemortem blood concentration.     

Instability of pancuronium in postmortem blood and liver taken after a fatal intramuscular Pavulon injection

The present study was designed to determine the stability of pancuronium in postmortem blood and liver during storage. Results were obtained using the method by Kerskes et al. [C.H.M. Kerskes, K.J. Lusthof, P.G.M. Zweipfenning, J.P. Franke, The detection and identification of quaternary nitrogen muscle relaxants in biological fluids and tissues by ion-trap LC-ESI-MS, J. Anal. Toxicol. 26 (2002) 29-34.], modified and validated in our laboratory. Target analytes were isolated after enzymatic hydrolysis followed by solid phase extraction (BondElut C18 column). Internal standardisation was carried out using laudanosine and the target ions were monitored by LC-ESI-MS (monitoring ions m/z 358 for IS and 286 for pancuronium). Materials were taken from a 46-year-old woman, who had been found dead. A syringe (2 ml) and an empty ampoule of Pavulon (4 mg/2 mL) were found in her hand. The residual volume of fluid in the syringe was 0.7 ml. An autopsy was performed six days after death. It revealed a needle mark on the left thigh. Postmortem materials (muscle from the injection site, blood and liver) and the syringe with fluid were stored for four months in a freezer at -20 degrees C. The initial pancuronium concentrations were 81 ng/mL in blood and 532 ng/g in liver. The analyte was stable when stored at -20 degrees C in blood even up to seven months. In liver samples its concentrations were variable. Pancuronium in blood stored at 20 degrees C underwent degradation very rapidly. After three months of storage these blood samples had concentrations not greater about 10% of the initial value. The degradation patterns of pancuronium depended on temperature and the biological matrix.     

氯胺酮在急性中毒大鼠体内的死后再分布研究

目的探索氯胺酮在大鼠体内的死后再分布变化规律及温度对再分布的影响。方法48只雄性SD大鼠随机分为2个实验组（室温组24只、冷藏组18只）和1个对照组（6只）,实验组大鼠以氯胺酮290mg／kg灌胃,45min后缺氧处死,分别置于室温（24℃）和冷藏（4℃）条件下,于死后不同时间（0、12、24、48h）取心血、外周血、肝、肺、肾、心肌、大脑,检测其中氯胺酮含量;对照组大鼠以生理盐水灌胃,各对应组织器官样品为空白对照。血和组织样品中加入内标物SKF。。后碱化,乙酸乙酯萃取,GC／MS全扫描定性,内标法、工作曲线法气相色谱定量分析。结果室温条件下,大鼠死后48h内随着死亡时间延长,心血、肺、肝中氯胺酮的浓度呈升高趋势（P〈0．05）,肾脏中氯胺酮的浓度先升高后下降（P〈0．05）,外周血、心肌和脑中氯胺酮的浓度无显著性变化（P〉0．05）。冷藏条件下,血液及组织中氯胺酮浓度变化无显著性差异（P〉0．05）,除心肌外,各样本浓度均低于相应时段室温条件保存的样本。结论氯胺酮在大鼠体内存在死后再分布现象。温度对大鼠死后血液及组织中氯胺酮浓度变化有较明显的影响。     

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.     

Distribution of Enantiomers of Methadone and Its Main Metabolite EDDP in Human Tissues and Blood of Postmortem Cases

Knowledge concerning the distribution of methadone in postmortem human tissue and the effect of postmortem redistribution on methadone is today limited making the choice of a suitable substitute for femoral blood difficult when this is not available. Cardiac blood, femoral blood, muscle, and brain tissue concentrations of the enantiomers of methadone and its metabolite 2‐ethyl‐1,5‐dimethyl‐3,3‐diphenylpyrrolinium were recorded for 155 postmortem cases. Brain and muscle tissue concentrations exceeded the femoral blood concentrations with a median fold of 2.3 and 1.6, respectively, but both had a better correlation than cardiac blood to femoral blood concentrations. The Kruskal–Wallis test showed a significant dependency on time and body mass index for some of the matrix ratios over femoral blood. We conclude brain or muscle tissue may constitute a better alternative for measurement of methadone than cardiac blood for situations in which femoral blood is not available, despite concentrations in both matrices being systematically higher.     

Disopyramide and Mianserin Intoxication: A Unique Fatal Case – Review of the Literature

Lethal occurrence is exceptional after disopyramide or mianserin poisoning. A case of intentional lethal intoxication with these drugs was reported, as well as a review of the literature. Pre‐ and postmortem blood concentrations of disopyramide or mianserin were assessed in a woman who died from acute cardiac failure after ingestion. The premortem blood concentration of disopyramide alone was considered lethal, and a toxic premortem concentration of mianserin was observed that may have increased cardiovascular failure induced by disopyramide because the metabolism of both drugs is mediated via cytochrome P450. Moreover, it was shown that the postmortem redistribution of disopyramide was limited, as pre‐ and postmortem concentrations were 48 and 65 mg/L, respectively. As regards mianserin, redistribution was observed after death with pre‐ and portmortem concentrations at 0.23 and 0.79 mg/L, respectively. This case illustrates that if postmortem blood concentration of disopyramide is known, the premortem concentration can be deduced.     

氯氮平在家兔体内死后再分布规律研究

目的阐明死后48h内家兔体内氯氮平再分布规律,为相关法医鉴定工作提供借鉴。方法取家兔15只,随机分为5组,以氯氮平灌胃,分别于死后0、6、12、24、48h取心血、外周静脉血、尿液、肝组织检测氯氮平浓度。结果家兔死亡后心血、外周静脉血、肝脏氯氮平浓度不断升高,尿液氯氮平浓度不断降低;死后早期浓度变化率大于晚期浓度变化率。死后48h心血、外周静脉血、肝脏、尿液氯氮平浓度分别为死后0h各检材氯氮平浓度的418%、193%、154%和29%。结论死亡一段时间后,提取生物检材,检测出的氯氮平浓度并不能准确反映刚死时的实际浓度。     

Popliteal Vein Blood Sampling and the Postmortem Redistribution of Diazepam,Methadone, and Morphine

Postmortem redistribution (PMR) refers to the site‐ and time‐related blood drug concentration variations after death. We compared central blood (cardiac and subclavian) with peripheral blood (femoral and popliteal) concentrations of diazepam, methadone, and morphine. To our knowledge, popliteal blood has never been compared with other sites. Intracardiac blood (ICB), subclavian blood (SB), femoral blood (FB), and popliteal blood (PB) were sampled in 30 cases. To assess PMR, mean concentrations and ratios were compared. Influence of postmortem interval on mean ratios was also assessed. Results show that popliteal mean concentrations were lower than those for other sites for all three drugs, even lower than femoral blood; mean ratios suggested that the popliteal site was less subject to PMR, and estimated postmortem interval did not influence ratios except for diazepam and methadone FB/PB. In conclusion, our study is the first to explore the popliteal site and suggests that popliteal blood is less prone to postmortem redistribution.     

MDMA的死后再分布及其机制

对MDMA死后再分布及其发生机制进行的动物实验和案例研究的文献,阐述MDMA死后心血浓度升高、死后通过胃肠道和气管内MDMA的再分布、MDMA在死后代谢再分布中的作用,以及死后再分布的发生机制与死后血液流动、顺浓度梯度扩散、毒物的代谢等有关的问题。     

阿维菌素在急性中毒死家兔体内的再分布研究

目的考察阿维菌素在急性中毒死家兔体内的再分布。方法按最小致死量一次性灌胃250mg/kg阿维菌素,HPLC法检测家兔死后0h、24h、48h和72h中阿维菌素的含量。结果给家兔一次性灌胃250mg/kg阿维菌素的临床死亡时间为120.6±9.2min(±s,n=10);测定了阿维菌素的致死血浓度和致死组织浓度;家兔死后0h~72h心血和各主要脏器组织中阿维菌素含量存在体内再分布现象;确定肝、肾、肺为最佳组织检材。结论阿维菌素在急性中毒死家兔体内的再分布数据,对法医办理此类案件具有重要参考价值。     

Preliminary study of the effect of acute antemortem haemorrhage on postmortem abdominal impedance in rats

Studies over many years have revealed a consistent, inverse relationship between extracellular impedance of the rat abdomen and postmortem interval (PMI). Recent studies have shown that this relationship can be improved by correcting measured impedances to their theoretically predicted values at an arbitrarily chosen temperature of 40 degrees C, thus rendering them independent of the tissues' temperature at the time of impedance measurement. The present study, undertaken as a part of an ongoing effort to identify variables which might influence postmortem rate of change in abdominal impedance, was aimed at studying the possible effect of acute antemortem haemorrhage on abdominal impedance. Sudden loss of approximately 30% of the total blood volume, immediately prior to the death was without statistically significant effect on the pattern of postmortem change in abdominal impedance. Thus, in the control and experimental rats, respectively, impedance decreased progressively from 58.7 +/- 1.8 and 68.0 +/- 11.3 omega, 1 h postmortem, to 31.5 +/- 2.2 and 33.7 +/- 4.7 omega at a postmortem interval of 120 h (n = 6 in each group). In both groups, the relationship between impedance and postmortem interval was either linear or curvilinear. These findings are believed to mitigate in favour of continued effort to examine the potential usefulness of abdominal impedance, as an index of postmortem interval, under conditions encountered in routine forensic investigation.