Lethal hypothermia - a sometimes elusive diagnosis

Concealed Homicides-A Postmortem Study and Review

ABSTRACT

A study was undertaken at Forensic Science SA, Adelaide, South Australia, of all cases of homicide (January 2003-December 2022) where the victims' bodies had been concealed. Three hundred twenty-six homicides were identified, which included 27 cases where bodies had been deliberately hidden (8%) (age range, 2-82 years; ave, 34.9 years; M:F = 1.5:1). Deaths were due to blunt force trauma (n = 11), sharp force trauma (n = 4), asphyxia (n = 4), gunshot wound (n = 2), and a combination of drowning and asphyxia (n = 1). In 5 cases, the cause of death was not determinable. The methods of concealment (which were sometimes overlapping) included the following: dumping at a hidden/isolated location (n = 8), burial (n = 7), dismembering (n = 3), incinerating (n = 3), hiding in a wheeled garbage bin (n = 2), disposing in garbage resulting in the remains being located at waste disposal facilities (n = 2), hiding in a shed (n = 1), under a concrete floor (n = 1), in a suitcase (n = 1), in a river (n = 1), in a mine shaft (n = 1), and in a septic tank (n = 1). Although it has been asserted that concealed homicides are rarely encountered in forensic practice, the current study has demonstrated that the bodies in at least 8% of victims of homicide in South Australia have undergone some form of concealment.

From suicide to accident - Case report - The significance of the medico-legal autopsies

INTRODUCTION

Suicide is the intentional and voluntary act of destroying one's own life, while an accident is an unintended event that involuntarily causes injury to one's health or destruction of life.

CASE PRESENTATION

We report a case of a 54-year-old male who was found in a forest in late November, approximately 500 m away from his car. He was positioned bent over a trunk of a tree with his head beneath the rest of his body. His pants were down to his knees, and there were soiled blades of grass and leaves on his body. Investigation of the case circumstances revealed that he had attempted suicide by carbon monoxide poisoning, using a hose connected to the exhaust pipe and running it through the window into the cabin. Window on the driver's side was broken with glass particles on the driver's seat. Wrappers from "Rivotril" tablets, a generic benzodiazepine, were also found in the car. Autopsy revealed the following: postmortem hypostasis was of a cherry red color and well pronounced on the upper part of the front of the body and face. Numerous bruises, contusions, and erosions were present all over the body. Frostbites were especially pronounced in the knees and elbows area. The synovial membranes were partially bloodstained and reddish in color. Opening the stomach revealed erosions of the gastric mucosa (Wischnewsky sign). Chemical toxicological analysis detected presence of benzodiazepines and carboxyhemoglobin (25%).

CONCLUSION

Based on the autopsy findings, chemical toxicological analyses, and investigation of the case circumstances, it has been concluded that the death occurred due to the combined effects of hypothermia, postural asphyxia and carboxyhemoglobin and benzodiazepine intoxication. The manner of death in this case is a combination of accidental and suicidal, as the victim attempted suicide but ultimately died due to exposure to low external temperature.

Deaths due to suspected hypothermia in sheep and alpacas on a Manawatū farm in New Zealand in mid-summer

CASE HISTORY

In mid-summer (February), 42 of a flock of 68 ram hoggets (approximately 5 months of age) and two of a group of 14 alpacas on a farm in the Manawatū region of New Zealand were found recumbent or dead following a period of persistent rain, strong winds and relatively low temperatures. The hoggets and alpacas had been shorn 4 and 53 days previously, respectively, and were in adequate to good body condition with access to ad libitum pasture. Post-mortem and histological examinations were undertaken on four hoggets and two alpacas.

CLINICAL FINDINGS

Apart from hypothermic body temperatures from four recumbent hoggets, nothing of significance was identified on clinical or gross pathological examination. Histological changes of vacuolar hepatopathy, renal tubular degeneration and pulmonary congestion were present in all animals examined.

DIAGNOSIS

Based on the history and clinical and pathological findings, hypothermia was highly probable to have been the cause of the deaths.

CLINICAL RELEVANCE

These cases emphasise the importance of shelter for recently shorn sheep and alpacas regardless of the season.

An unusual case of fatal hypothermia involving topical diphenhydramine

PURPOSE

Diphenhydramine is an antihistamine drug widely used to alleviate symptoms caused by allergies and the common cold. Diphenhydramine-involved fatalities have been reported in the past but usually involving overdose by ingestion. We report a peculiar case of fatal hypothermia during non-winter season involving topical diphenhydramine.

METHODS

A 23-year-old male with no known preexisting medical conditions was found dead in the bathroom of his apartment with a small amount of running water on his back. Postmortem examinations and toxicological analysis on blood and urine were performed.

RESULTS

Color difference was apparent between the right and left cardiac blood. Wischnewski spots were observed in the gastric mucosa. Histological examination revealed no obvious findings that could attribute to serious cardiovascular events. Drug screening by gas chromatograph-tandem mass spectrometry (GC/MS/MS) detected diphenhydramine in blood and urine. Further quantification revealed the postmortem concentrations to be 0.44 μg/mL in blood and 2500 μg/mL in urine.

CONCLUSIONS

The cause of death was determined to be hypothermia. Diphenhydramine-induced drowsiness and possible intrinsic cardiac factor may have led to prolonged impaired consciousness, preventing his ability to escape from the running cold water leading to hypothermia and death.

Attenuated total reflection-Fourier transform infrared spectroscopy: a universal analytical technique with promising applications in forensic analyses

Contemporary criminal investigations are based on the statements made by the victim and the eyewitnesses. They also rely on the physical evidences found in the crime scene. These evidences, and more particularly biological ones, have a great judicial value in the courtroom. They are usually used to revoke the suspect’s allegations and confirm or refute the statements made by the victim and the witnesses. Stains of body fluids are biological evidences highly sought by forensic investigators. In many criminal cases, the success of the investigation relies on the correct identification and classification of these stains. Therefore, the adoption of reliable and accurate forensic analytical methods seems to be of vital importance to attain this objective. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) is a modern and universal analytical technique capable of fingerprint recognition of the analyte using minimal amount of the test sample. The current systematic review aims to through light on the fundamentals of this technique and to illustrate its wide range of applications in forensic investigations. ATR-FTIR is a nondestructive technique which has demonstrated an exceptional efficiency in detecting, identifying and discriminating between stains of various types of body fluids usually encountered in crime scenes. The ATR-FTIR spectral data generated from bloodstains can be used to deduce a wealth of information related to the donor species, age, gender, and race. These data can also be exploited to discriminate between stains of different types of bloods including menstrual and peripheral bloods. In addition, ATR-FTIR has a great utility in the postmortem investigations. More particularly, in estimating the postmortem interval and diagnosing death caused by extreme weather conditions. It is also useful in diagnosing some ambiguous death causes such as fatal anaphylactic shock and diabetic ketoacidosis.

The Thermal Environment of Housing and Its Implications for the Health of Older People in South Australia: A Mixed-Methods Study

Older people are often over-represented in morbidity and mortality statistics associated with hot and cold weather, despite remaining mostly indoors. The study “Improving thermal environment of housing for older Australians” focused on assessing the relationships between the indoor environment, building characteristics, thermal comfort and perceived health/wellbeing of older South Australians over a study period that included the warmest summer on record. Our findings showed that indoor temperatures in some of the houses reached above 35 °C. With concerns about energy costs, occupants often use adaptive behaviours to achieve thermal comfort instead of using cooling (or heating), although feeling less satisfied with the thermal environment and perceiving health/wellbeing to worsen at above 28 °C (and below 15 °C). Symptoms experienced during hot weather included tiredness, shortness of breath, sleeplessness and dizziness, with coughs and colds, painful joints, shortness of breath and influenza experienced during cold weather. To express the influence of temperature and humidity on perceived health/wellbeing, a Temperature Humidity Health Index (THHI) was developed for this cohort. A health/wellbeing perception of “very good” is achieved between an 18.4 °C and 24.3 °C indoor operative temperature and a 55% relative humidity. The evidence from this research is used to inform guidelines about maintaining home environments to be conducive to the health/wellbeing of older people.

Postmortem diagnosis of fatal hypothermia/hyperthermia by spectrochemical analysis of plasma

Postmortem diagnosis of extreme-weather-related deaths is a challenging forensic task. Here, we present a state-of-the-art study that employed attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopy in combination with Chemometrics for postmortem diagnosis of fatal hypothermia/hyperthermia by biochemical investigation of plasma in rats. The results of principal component analysis (PCA) and spectral analysis revealed that plasma samples from the fatal hypothermia, fatal hyperthermia, and control groups, are substantially different from each other based on the spectral variations associated with the lipid, carbohydrate and nucleic acid components. Two partial least squares-discriminant analysis (PLS-DA) classification models (hypothermia-nonhypothermia and hyperthermia-nonhyperthermia binary models) with a 100% accuracy rate were constructed. Subsequently, internal cross-validation was performed to assess the robustness of these two models, which resulted in 98.1 and 100% accuracy. Ultimately, classification predictions of 42 unknown plasma samples were performed by these two models, and both models achieved 100% accuracy. Additionally, our results demonstrated that hemolysis and postmortem hypothermic/hyperthermic effects did not weaken the prediction ability of these two classification models. In summary, this work demonstrates ATR-FTIR spectroscopy's great potential for postmortem diagnosis of fatal hypothermia/hyperthermia.

Cold-induced protein RBM3 orchestrates neurogenesis via modulating Yap mRNA stability in cold stress

RBM3 plays a protective role in embryonic neurogenesis. This study finds that maternal cold stress affects the embryonic brain development via RBM3 and Yap. When RBM3 is knocked down or knocked out under the maternal cold stress, the embryonic neurogenesis was impaired.

In mammals, a constant body temperature is an important basis for maintaining life activities. Here, we show that when pregnant mice are subjected to cold stress, the expression of RBM3, a cold-induced protein, is increased in the embryonic brain. When RBM3 is knocked down or knocked out in cold stress, embryonic brain development is more seriously affected, exhibiting abnormal neuronal differentiation. By detecting the change in mRNA expression during maternal cold stress, we demonstrate that Yap and its downstream molecules are altered at the RNA level. By analyzing RNA-binding motif of RBM3, we find that there are seven binding sites in 3′UTR region of Yap1 mRNA. Mechanistically, RBM3 binds to Yap1-3′UTR, regulates its stability, and affects the expression of YAP1. RBM3 and YAP1 overexpression can partially rescue the brain development defect caused by RBM3 knockout in cold stress. Collectively, our data demonstrate that cold temperature affects brain development, and RBM3 acts as a key protective regulator in cold stress.