External foam and the post-mortem period in freshwater drowning; results from a retrospective study in Amsterdam, the Netherlands

Postmortem CT analysis of paranasal sinuses using an experimental model of drowning

Fluid-filled paranasal sinuses are suggested to be a valuable tool to distinguish between drowning and non-drowning postmortem, yet the mechanisms governing fluid entry remains unknown. We investigate if fluid-filled paranasal sinuses are caused by a passive influx from submersion or an active aspiration mechanism during drowning. The ovine nasal cavity and maxillary sinuses are remarkably similar anatomically to humans, and have been used for endoscopic surgical training in recent decades. We submerged 15 decapitated ovine heads from agricultural waste at a depth of 2 m in flowing water for 1, 8, and 24 h and 7 days. Paranasal sinuses were CT imaged and compared pre- and post-submersion to non-submerged controls. Furthermore, we examined the paranasal sinuses of a single homicide case of a non-drowned submerged subject. Results demonstrate that fluid passively enters the maxillary sinus postmortem in the non-drowned ovine heads following 1 h of submersion. Fluid volume was independent of submersion time and influenced by time out of water as well as handling, since volume was reduced between consecutive CT scans. In contrast to our hypothesis, the filling of the paranasal sinuses is due to passive influx of fluid from submersion rather than an active aspiration during drowning. The observation that paranasal sinuses were fluid-filled in a single medico-legal case of postmortem submersion supports the finding of passive influx. Consequently, careful interpretation of fluid-filled paranasal sinuses is required when bodies are found in water, as the finding cannot distinguish between postmortem submersion and drowning.

Estimation of the post-mortem interval; added value of mechanical excitability of human skeletal muscle

Estimation of the post-mortem interval (PMI) is mainly based on the state of body cooling, post-mortem lividity (livor mortis) and post-mortem muscle stiffness (rigor mortis). However, the time span of development of these post-mortem phenomena are influenced by a variety of factors concerning the body of the deceased and the environment in which the body is found. Subsequently, this leads to a substantial spread in upper and lower limits of PMI based on determination of the state of these phenomena. Moreover, interpretation of post-mortem phenomena like lividity, rigor and interpretation of the correction factor for Henssge's nomogram is subjective. For this reason, PMI estimations are often broad, possibly too broad to be helpful for answering questions which are relevant for the criminal investigation. Therefore, combining the outcome of different methods for estimating the PMI, the so-called compound method, is recommended. Supravital muscle reaction by mechanical stimulation of skeletal muscle is a less known aspect of the compound method. Here we present a series of cases series in which supravital muscle reaction contributed to a more precise estimation of the PMI.

Termination of Cardiopulmonary Resuscitation in Mountain Rescue: A Scoping Review and ICAR MedCom 2023 Recommendations

Lugnet, Viktor, Miles McDonough, Les Gordon, Mercedes Galindez, Nicolas Mena Reyes, Alison Sheets, Ken Zafren, and Peter Paal. Termination of cardiopulmonary resuscitation in mountain rescue: a scoping review and ICAR MedCom 2023 recommendations. High Alt Med Biol. 24:274-286, 2023. Background: In 2012, the International Commission for Mountain Emergency Medicine (ICAR MedCom) published recommendations for termination of cardiopulmonary resuscitation (CPR) in mountain rescue. New developments have necessitated an update. This is the 2023 update for termination of CPR in mountain rescue. Methods: For this scoping review, we searched the PubMed and Cochrane libraries, updated the recommendations, and obtained consensus approval within the writing group and the ICAR MedCom. Results: We screened a total of 9,102 articles, of which 120 articles met the inclusion criteria. We developed 17 recommendations graded according to the strength of recommendation and level of evidence. Conclusions: Most of the recommendations from 2012 are still valid. We made minor changes regarding the safety of rescuers and responses to primary or traumatic cardiac arrest. The criteria for termination of CPR remain unchanged. The principal changes include updated recommendations for mechanical chest compression, point of care ultrasound (POCUS), extracorporeal life support (ECLS) for hypothermia, the effects of water temperature in drowning, and the use of burial times in avalanche rescue.

The nose as a feature of forensic practice

The nose is a prominent facial structure which is too often overlooked by forensic medicine practitioners. Studies that consider the role of the nose in forensic practice are scattered throughout scientific literature. We provide a brief review of these.

Macromorphological findings in cases of death in water: a critical view on "drowning signs"

Death in water is a challenging issue in forensic pathology since from natural death to homicide all circumstances of death in water are conceivable. Therefore, the correct interpretation of all abnormal autopsy findings is important. In order to determine a death by drowning, numerous internal and external signs of drowning are already described. However, these are supposed to be influenced by various factors reducing their significance and evidence. Moreover, the autopsy of water corpses often reveals further pathological findings that should not be underestimated for determining the cause of death. The aim of this study was to set frequencies of the observed drowning signs in context to the forensic literature and to identify possible influencing factors. In this study, we observed that pathological organ changes of the cardiovascular system were significantly more common in corpses after shortened (atypical) drowning processes than in classical drowned victims. Furthermore only a complete formation of external foam, immediately after the corpse’s recovery, was exclusively found in drowning victims. All other drowning signs were either also observed in non-drowning deaths in water or no information could be provided with reasonable assurance. In addition, many of the examined drowning signs were negatively affected by prolonged postmortem intervals, putrefaction, or resuscitation attempts. It can be concluded from our analysis that morbidity is an important factor in deaths in water. Morbidity can support a death by drowning in case of incidents in water. For the examined drowning signs, no high diagnostic certainty could be observed. Nevertheless, these findings can increase their diagnostic value—if forensic physicians take influencing factors into consideration.

The persistent problem of drowning - A difficult diagnosis with inconclusive tests

Although the diagnosis of drowning may appear straightforward the reality is that it is sometimes one of the most difficult in forensic pathology. To begin with, there is no universal agreement on what constitutes drowning with some definitions using the term in the absence of a lethal outcome. Next are the significant problems that arise in finding immersed bodies and in assessing the death scene. Prolonged post mortem intervals are associated with artefactual modifications of the body from putrefaction and post mortem animal predation. Both of these may create and disguise injuries. The absence of pathognomonic pathological features at autopsy and the presence of potentially life threatening underlying organic illnesses complicate determination of both the cause and manner of death. There may even be no autopsy findings to indicate that immersion had occurred. Finally, the unreliability of laboratory tests with significant overlap with control cases where death had no association with immersion presents further problems. Thus lethal drowning remains a complex event that requires the use of a wide variety of information sources, not just data gleaned from the dissection table.

Can pulmonary foam arise after postmortem submersion in water? An animal experimental pilot study

It is difficult to differentiate drowning from postmortem submersion. Pulmonary foam can be found in bodies retrieved from water. It is unknown whether foam is a result of drowning or if it also forms after postmortem submersion. We divided deceased piglets into three groups: postmortem saltwater submersion (N = 20), postmortem freshwater submersion (N = 20) and dry-land controls (N = 20). All carcasses underwent endoscopic examination within 24 h of death and the presence of external and internal pulmonary foam was scored. No external foam was detected in the postmortem freshwater or the postmortem saltwater group. Internal foam was seen in 35% of the postmortem freshwater and 40% of the postmortem saltwater group. No external or internal foam was detected in the dry land control group. The literature shows external as well as internal foam in drowned humans. Internal foam is seen in postmortem submersion in the current piglet study and antemortem submersion in the literature in humans, and can therefore not be used to support/refute the diagnosis of drowning. No external foam was present in the postmortem submersed piglets, yet has been described in drowned humans. Hence the presence of external foam in bodies recovered from water may be indicative for drowning. The presence of external foam is a potentially valuable clinical sign in distinguishing drowning from postmortem submersion.