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Introduction: Disrupted weather patterns are associated with climate change. Between 2001 and 2018, nearly 74% of disasters were water-related, including floods and cyclones. Such water-related cataclysmic events increase the risk of drowning. We aimed to map evidence on the impact of climate change on water-related physical events, associated human migration, and drowning burden in India. MATERIALS AND METHODS: We searched electronic databases, government reports, and relevant websites to map evidence on water-related physical events (including but not limited to sea-level rise, glacier bursts, lake bursts, floods, rainfall, cyclones, and droughts) and consequent human migration using narrative review approach, while drowning burden through scoping review approach. We summarized the results narratively. Results: Evidence from 48 studies and seven reports suggest that India will witness the greatest sea-level rise, significantly impacting poor coastal communities. An increase in droughts, cyclonic rainfall, storms, and floods, with increasing surface rainwater and streamflow water, due to melting glaciers is expected. Climate change–triggered migration is expected notably in northeast and south India, making farmers, drivers, street vendors, women, and youth most vulnerable. No direct evidence was identified on the impact of climate change, water-related disasters, meteorological events, or seasonal variations on drowning from India. Conclusion: Our study highlights a significant gap in the availability of context-specific and localized data to improve disaster response and strengthen public health systems, especially for areas most vulnerable to climate change. There is an urgent need to generate new knowledge and understanding of climate change, water-related or meteorological events, and seasonal variations’ impact on drowning burden as the level of risk remains unknown.

Abstract Background Drowning remains a common cause of death among children. However, the epidemiology and impact of drowning in Thailand was underexplored. This study aimed to analyze the epidemiology and clinical outcomes of pediatric drowning in Thailand and to determine the factors associated with the need for intubation and mortality. Methods Data derived from the Thai healthcare delivery system for the period between 2015 and 2019 were used to examine the monthly admissions, mortality rates, length of hospital stay, and the number of patients who received endotracheal intubation. Multivariate logistic regression analysis was employed to identify the risk factors associated with the need for intubation and mortality. Results Of the 4,911, 58.8% were under six years old, 63.5% were male, and 31.2% were from the Northeastern region. The majority drowned during April, which is the summer season in Thailand. Among these patients, 28.8% required intubation, with the highest proportion found in the 6-

Abstract Background Trauma guidelines on spinal motion restriction (SMR) have changed drastically in recent years. An international group of experts explored whether consensus could be reached and if guidelines on SMR performed by trained lifeguards and prehospital EMS following in-water traumatic spinal cord injury (TSCI) should also be changed. Methods An international three-round Delphi process was conducted from October 2022 to November 2023. In Delphi round one, brainstorming resulted in an exhaustive list of recommendations for handling patients with suspected in-water TSCI. The list was also used to construct a preliminary flowchart for in-water SMR. In Delphi round two, three levels of agreement for each recommendation and the flowchart were established. Recommendations with strong consensus (≥ 85% agreement) underwent minor revisions and entered round three; recommendations with moderate consensus (75–85% agreement) underwent major revisions in two consecutive phases; and recommendations with weak consensus (

This article resurfaces an enslaved female whom we encounter, drowning, in the archive of the Middelburgse Commercie Compagnie (MCC). To unfold a reading beyond the transcription of her commodified death, I investigate the five localities that conditioned her bodily inscription into history: the archive, the law, the ship, the ocean, and the womb. Traveling through these localities, I disclose, at once, the historical violence against black females through the transatlantic slave trade system and the excess black females proved to be to this very system. Excessive thus, black female lineage provides an alternative to white, patriarchic systems of relation.

Abstract Objective Patients with epilepsy have high risk of experiencing uncommon causes of death. This study aimed to evaluate patients who underwent unusual deaths related to epilepsy and identify factors that may contribute to these deaths and may also include sudden unexpected death in epilepsy (SUDEP). Methods We analyzed 5291 cases in which a postmortem imaging (PMI) study was performed using plane CT, because of an unexplained death. A rapid troponin T assay was performed using peripheral blood samples. Clinical information including the cause of death suspected by the attending physician, body position, place of death, medical history, and antiseizure medications was evaluated. Results A total of 132 (2.6%) patients had an obvious history of epilepsy, while 5159 individuals had no history of epilepsy (97.4%). Cerebrovascular disease was the cause of death in 1.6% of patients in the group with epilepsy, and this was significantly lower than that in the non‐epilepsy group. However, drowning was significantly higher (9.1% vs. 4.4%). Unspecified cause of death was significantly more frequent in the epilepsy group (78.0% vs. 57.8%). Furthermore, the proportion of patients who demonstrated elevation of troponin T levels without prior cardiac disease was significantly higher in the epilepsy group (37.9% vs. 31.1%). At discovery of death, prone position was dominant (30.3%), with deaths occurring most commonly in the bedroom (49.2%). No antiseizure medication had been prescribed in 12% of cases, while 29.5% of patients were taking multiple antiseizure medications. Significance The prevalence of epilepsy in individuals experiencing unusual death was higher than in the general population. Despite PMI studies, no definitive cause of death was identified in a significant proportion of cases. The high troponin T levels may be explained by long intervals between death and examination or by higher incidence of myocardial damage at the time of death. Plain Language Summary This study investigated unusual deaths in epilepsy patients, analyzing 5291 postmortem imaging cases. The results showed that 132 cases (2.6%) had a clear history of epilepsy. In these cases, only 22% cases were explained after postmortem examination, which is less than in non‐epilepsy group (42.2%). Cerebrovascular disease was less common in the epilepsy group, while drowning was more common. Elevated troponin T levels, which suggest possibility of myocardial damage or long intervals between death and examination, were also more frequent in the epilepsy group compared to non‐epilepsy group.

An 18-year-old drowning victim was successfully resuscitated using prehospital veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Despite 24 min of submersion in water with a surface temperature of 15 °C, the patient was cannulated on-scene and transported to a trauma center. After ICU admission on VA-ECMO, he was decannulated and extubated by day 5. He was transferred to a peripheral hospital on day 6 and discharged home after 3.5 weeks with favorable neurological outcome of a Cerebral Performance Categories (CPC) score of 1 out of 5. This case underscores the potential of prehospital ECMO in drowning cases within a well-equipped emergency response system.

Objective: The aim of this study was to analyze the feasibility of a new resuscitation strategy in which breaths are provided during automated external defibrillator (AED) rhythm analysis, and to evaluate its impact on chest compressions (CC) quality and the peri-analysis time. Method: A randomized simulation study, comparing two cardiopulmonary resuscitations strategies, has been conducted: the standard strategy (S1) with strategy involving ventilation during AED analysis (S2). Thirty lifeguards have performed both strategies in a cross-over study design during 10 min of CPR. Results: The number of ventilations per 10 min increases from 47 (S1) to 72 (S2) (p

Abstract The aim of this study is to describe a case of haemoglobinuria in a cat after near‐drowning. A 6‐year‐old male neutered domestic short hair cat weighing 6.5 kg with a pre‐existing seizure disorder presented to an emergency hospital after near‐drowning in a swimming pool during a seizure episode. On presentation, the patient was obtunded, dyspnoeic, bradycardic and hypothermic. Imaging revealed evidence of severe bilateral pulmonary infiltrates. Treatment with intravenous diazepam, amoxicillin, fluid therapy, active warming and oxygen therapy was administered. The cat developed haemoglobinuria approximately 6 h after nearly drowning. Despite improvements in mentation, pulse quality and heart rate, respiratory compromise and poor oxygen saturation persisted, prompting euthanasia approximately 10 h after admission. To the author's knowledge, this is the first reported clinical case of haemoglobinuria following near‐drowning in veterinary medicine.

Abstract Background Improving oxygenation and ventilation in drowning patients early in the field is critical and may be lifesaving. The critical care interventions performed by physicians in drowning management are poorly described. The aim was to describe patient characteristics and critical care interventions with 30-day mortality as the primary outcome in drowning patients treated by the Danish Air Ambulance. Methods This retrospective cohort study with 30-day follow-up identified drowning patients treated by the Danish Air Ambulance from January 1, 2016, through December 31, 2021. Drowning patients were identified using a text-search algorithm (Danish Drowning Formula) followed by manual review and validation. Operational and medical data were extracted from the Danish Air Ambulance database. Descriptive analyses were performed comparing non-fatal and fatal drowning incidents with 30-day mortality as the primary outcome. Results Of 16,841 dispatches resulting in a patient encounter in the six years, the Danish Drowning Formula identified 138 potential drowning patients. After manual validation, 98 drowning patients were included in the analyses, and 82 completed 30-day follow-up. The prehospital and 30-day mortality rates were 33% and 67%, respectively. The National Advisory Committee for Aeronautics severity scores from 4 to 7, indicating a critical emergency, were observed in 90% of the total population. They were significantly higher in the fatal versus non-fatal group (p

Abstract Background The study aims to update the specific classification of mechanisms of death in swimming and to demonstrate these categories are reasonable, by analyzing more characteristics of death cases, evaluating the available evidence and determining their quality. Methods Original articles were queried from PubMed, Web of Science, Embase databases, Cochrane Library, and Scopus. Included studies, which were evaluated as level 4 evidence or higher according to the Oxford Centre for Evidence-Based Medicine, discussed hypothesized mechanisms of death in swimming. Parameters analyzed in this study included decedents’ characteristics, outcome measures, findings, methodological index for non-randomized studies (MINORS), and critical evaluation of each study classified by death mechanism. Results A total of twenty-five studies were included for further analysis: fourteen were associated with cardiovascular diseases, two were about cerebrovascular diseases, two contained respiratory diseases, seven were about hazardous conditions and three contained other drownings, which provided evidence for mechanisms of death. Conclusions It is found that cardiovascular disease is the main cause or contributing factor of death in swimming. Respiratory diseases and cerebrovascular diseases are difficult to be definitive mechanism categories due to insufficient evidence. Hazardous conditions appear to be one of the possible risk factors because there are more cases of deaths from unsafe environments in swimming, but further statistics and research are still needed to support this view. Our study may have important implications for developing potential prevention strategies for sports and exercise medicine. Trial registration PROSPERO ID (CRD42021267330). Registered Aug 13th 2021.

Drowning is among the most common reasons for children’s death aged one to fourteen around the globe, ranking as the third leading cause of unintentional injury death. With rising populations and the growing popularity of swimming pools in hotels and villas, the incidence of drowning has accelerated. Accordingly, the development of systems for detecting and preventing drowning has become increasingly critical to provide safe swimming settings. In this paper, we propose a comprehensive review of recent existing advancements in automated drowning detection and prevention systems. The existing approaches can be broadly categorized according to their objectives into two main groups: detection-based systems, which alert lifeguards or parents to perform manual rescues, and detection and rescue-based systems, which integrate detection with automatic rescue mechanisms. Automatic drowning detection approaches could be further categorized into computer vision-based approaches, where camera-captured images are analyzed by machine learning algorithms to detect instances of drowning, and sensing-based approaches, where sensing instruments are attached to swimmers to monitor their physical parameters. We explore the advantages and limitations of each approach. Additionally, we highlight technical challenges and unresolved issues related to this domain, such as data imbalance, accuracy, privacy concerns, and integration with rescue systems. We also identify future research opportunities, emphasizing the need for more advanced AI models, uniform datasets, and better integration of detection with autonomous rescue mechanisms. This study aims to provide a critical resource for researchers and practitioners, facilitating the development of more effective systems to enhance water safety and minimize drowning incidents.

Aim: Investigate long-term outcome in paediatric submersion-related cardiac arrests (CA). Methods: Children (age one day-17 years) were included if admitted to the Erasmus MC Sophia Children’s Hospital, after drowning with CA, between 2002 and 2019. Primary outcome was survival with favourable neurological outcome, defined as a Paediatric Cerebral Performance Category (PCPC) score of 1–3 at longest available follow-up. Secondary outcome were age-appropriate neuropsychological assessments at longest available follow-up. Results: Upon hospital admission, 99 children were included (median age at time of CA 3.2 years [IQR 2.0–5.9] and 65% males). Forty children died in-hospital (no return of circulation (45%) or withdrawal of life sustaining therapies (55%)) and 4 children deceased after hospital discharge due to complications following the drowning-incident. Among survivors, with a median follow-up of 2.3 years [IQR 0.2–5.5], 47 children had favourable neurological outcome (i.e. PCPC 1–3) and 8 children unfavourable (unfavourable outcome group total n = 52, i.e. PCPC 4–5 or deceased). Twenty-six (47%) children participated in a neuropsychological assessment (median follow-up 4.0 years [IQR 2.3–8.7]). Compared with normative test data, participants obtained worse general (p = 0.008) and performance (p = 0.003) intelligence scores, processing speed (p = 0.002) and visual motor integration scores (p = 0.0012). Conclusions: Although overall outcome in survivors was favourable at longest available follow-up, significant deficits in neuropsychological assessments were found. This study underlines the need for a standardized long term follow-up program as standard of care in paediatric drowning with CA.

Drowning remains a significant global health concern, claiming over 300,000 lives annually, with a disproportionate impact on young individuals in low-and middle-income countries. Conventional mechanical ventilation, while common, falls short in addressing the hypoxemia and hypercapnia often observed in severe near-drowning cases. Veno-venous extracorporeal membrane oxygenation (vvECMO) emerges as a critical intervention for cardiopulmonary failure post-drowning. This case report delves into the pivotal role of ischemia–reperfusion injury (IRI) in a near-drowning-related pathology. Following the initial insult, reoxygenation exacerbates the inflammatory cascade, resulting in a surge of pro-inflammatory mediators. In this context, CytoSorb®, a hemoadsorption cartridge, demonstrates promise by effectively removing these mediators from circulation. This report outlines its application in a critically ill adolescent patient who experienced near-drowning, presenting a compelling case for CytoSorb as an adjunctive therapy in managing IRI-induced hyperinflammation.

Abstract Background Drowning is the leading cause of death for toddlers. When caregivers are knowledgeable about water safety, they can provide the best protection against drowning. The aim of this study is to survey caregivers of toddlers to better understand factors associated with water safety knowledge, attitudes about pool supervision, and toddler water competency skills. Methods An online survey of 650 parents/caregivers of 1–4-year-old toddlers asked about the caregiver’s water safety and swimming background and views on pool supervision. Surveys included a true/false section of ten basic water safety knowledge questions. Caregivers also reported on toddler swim lesson history and whether their toddler could perform six standard water competency skills. Linear regression identified factors predictive of water safety knowledge. Results On average, caregivers selected the correct answer on six out of ten water safety knowledge questions. Water safety knowledge was predicted by the relationship of the caregiver to the toddler, gender, race, education, prior CPR training, caregiver swim capability, and reported pool supervision style. On average, caregivers reported that their toddler could perform half of the water competency skills. The majority of the toddlers had taken swimming lessons. One third of caregivers believed that after a toddler has had swimming lessons, they don’t need to be watched as closely when they are in a pool. Conclusions Findings suggest that water safety knowledge is poor and that there are misconceptions about toddler supervision needs. Efforts are needed to improve water safety knowledge and to change perceptions about supervision among caregivers of toddlers.

Abstract Background Co-ordinated, evidence-based policy and programmatic efforts are needed to respond to complex drowning prevention problems. Comprehensive, current, and robust data are vital for agenda setting, burden and risk factor identification, intervention design and evaluation, as well as setting policy. We aim to record methods used in, and identify impacts of, the development of a national fatal drowning database (NFDD) in Australia, including lessons learned across research, policy, and practice. Methods We employ a case study method using process mapping and document review to explore the evolution, drivers and impacts of the NFDD. We analyse methodological approaches including those relating to data definitions, drowning case collection, and management, as well as tracking the various outputs of the NFDD. We describe a development timeline that presents impact of drowning prevention policy, and research agendas on database development, and research investments more specifically. Results Our study identified that the collected variables grew 20-fold from 2002 to 2022, reaching 259 variables, and 5,692 unique cases of fatal drowning. The NFDD employs data triangulation methodology, combining keyword and targeted searches of coronial files, media report monitoring, and organisational data provision. Database development is influenced by the Australia Water Safety Strategy, policymaker and practitioner-initiated research agendas, and identification of knowledge gaps. We identified numerous outputs spanning publications, media, intervention development, and legislative submissions. Conclusion A comprehensive and robust NFDD informed by policymaker and practitioner input can enhance surveillance, policy, and intervention development for drowning prevention. Employing mixed data collection and validation methods can supplement weaknesses in official data sources. There is a need for the NFDD to continue to evolve in its application while maintaining rigorous case identification and data quality assurance processes. Despite significant investment, the outputs and influence on drowning prevention practice in Australia has been extremely valuable and contributed to sizeable reductions in Australia’s fatal drowning rate.

Abstract Background Drowning is one of the leading causes of death worldwide and presents with a wide range of symptoms, from simple coughing to cardiac or pulmonary failure. In severe cases, extracorporeal membrane oxygenation (ECMO) should be considered as a rescue therapy. Therefore, we sought to analyse ECMO usage, outcomes and predictive factors in drowned patients. Methods The Federal Statistical Office of Germany provided the study data. The patients included experienced drowning (ICD T75.1) and ECMO (OPS 8–852.0, 8–852.3) between 2007 and 2020. All age groups were included. Mortality was calculated for the total population and for ECMO patients. A multiple logistic regression model for ECMO patients was applied to account for predefined patient characteristics and complications. Results Of 12,354 patients who were hospitalised due to drowning, 237 patients (1.9%) received ECMO. Hospital mortality was 14.1% (n = 1741) overall and 74.7% (n = 177) for ECMO patients. In-hospital mortality was positively associated with cardiopulmonary resuscitation (CPR) before admission (odds ratio [OR] 4.49, 1.31–15.39) and in-hospital CPR (OR 6.28, 2.76–14.31). Stroke (OR 0.14, 0.02–0.96) and drug abuse (OR 0.05, 0.01–0.45) were negatively associated with in-hospital mortality. Neither the ECMO mode nor the patient’s age and sex had statistically significant effects on survival. Conclusion This study indicates that survival in drowned patients who receive ECMO is lower than previously reported. The proportion of paediatric patients was also smaller than expected. As the effects of different ECMO modes on mortality remain unclear, the need for further study remains great.

Abstract Drowning is a major public health issue internationally. In August 2022, a report was released by members of the Central Texas Drowning Prevention Action Team that provided data on drowning fatalities in Texas between 2006 and 2020 and offered recommendations for drowning prevention actions. The information in the Texas drowning report is an important contribution to the field of injury prevention. The aim of this editorial is to allow the information in the report to be available to a wider audience and potentially used as a model for other states.

Abstract Drowning is the third leading cause of injury death in the pediatric population worldwide, with incidence peaking among those aged 1–4 years and again in adolescence. The purpose of this commentary is to review the basic pathophysiology of drowninginjury and factors that affect the outcome, such as submersion and hypothermia. We also discuss principles of prehospital and in-hospital management, comprising resuscitation and stabilization, administration of oxygen and intravenous liquids, and central reheating. Even though the mortality rate has decreased in recent years, further investments and safety measures are needed to prevent child drowning deaths.

Abstract Background Drowning is an important public health problem. Some evidence suggests that the risk of drowning is not distributed evenly across the general population. However, there has been comparatively little research on inequalities in drowning mortality. To address this deficit, this study examined trends and sociodemographic inequalities in mortality from unintentional drowning in the Baltic countries and Finland in 2000–2015. Methods Data for Estonia, Latvia and Lithuania came from longitudinal mortality follow-up studies of population censuses in 2000/2001 and 2011, while corresponding data for Finland were obtained from the longitudinal register-based population data file of Statistics Finland. Deaths from drowning (ICD-10 codes W65–W74) were obtained from national mortality registries. Information was also obtained on socioeconomic status (educational level) and urban-rural residence. Age-standardised mortality rates (ASMRs) per 100 000 person years and mortality rate ratios were calculated for adults aged 30–74 years old. Poisson regression analysis was performed to assess the independent effects of sex, urban-rural residence and education on drowning mortality. Results Drowning ASMRs were significantly higher in the Baltic countries than in Finland but declined by nearly 30% in all countries across the study period. There were large inequalities by sex, urban-rural residence and educational level in all countries during 2000–2015. Men, rural residents and low educated individuals had substantially higher drowning ASMRs compared to their counterparts. Absolute and relative inequalities were significantly larger in the Baltic countries than in Finland. Absolute inequalities in drowning mortality declined in all countries across the study period except between urban and rural residents in Finland. Changes in relative inequalities were more variable during 2000–2015. Conclusion Despite a sharp reduction in deaths from drowning in the Baltic countries and Finland in 2000–2015, drowning mortality was still high in these countries at the end of the study period with a substantially larger risk of death seen among men, rural residents and low educated individuals. A concerted effort to prevent drowning mortality among those most at risk may reduce drownings considerably in the general population.

Water is an essential symbol of life "Without water, life would not exist", an antithesis is found when it can also take away your life, drowning. Every life lost has a countless value, a famous author portrayed this significance quoting "I believe that the life of a man is superior to all the riches that fortune can provide". Man, and water have had a relationship since the beginning of their existence being noted for its value and importance in Christianity. In the Old Testament with Isaiah (I 40.3-5) he mentioned water as a symbol of God's Spirit and allegory to his work (Mt 3.13-17). With Jesus Christ, water for people from Israel, was known to be as a sign of ablution. Its significance in the Christian faith is through baptism, with which the preaching of Jesus begins. Baptism comes from the Greek "baptisma" (immersion-act of immersing). The failure to submerge, with the etymological origin of baptism, is the accident called drowning.

Introduction: Drowning is one of the most prevalent accidents in aquatic environments. Although drowning has been noticed by healthcare policymakers in the world today, the issue of drowning has been neglected in the safety management of students. This research was conducted with the aim of investigating the predictors of adopting preventive behaviors from drowning trauma among students in the west of Tehran city with the approach of safety management. Material and Methods: This study was descriptive-analytical (cross-sectional). The statistical population of this research included all parents of students who were studying in the first grade of the selected public schools in West of Tehran city in the academic year of 2021-2022 (N=3000). The random convenience sampling was used and 340 parents participated in this study. The data collection tool was a researcher-made questionnaire with a new approach to safety management (preventing accidents by doing preventive behaviors) based on a protection motivation model (preventive behavior model), of which reliability and validity were checked. Data analysis was done using SPSS 26 software and Pearson correlation test and linear regression. Results: The constructs of the protection motivation model explained 67% of the variance of the behavioral intention of protection motivation and 69.7% students had no history of taking swimming classes. The highest correlation was between behavior and perceived costs (r=-0.579 and P

Ferroptosis, a novel programmed cell death characterized by intracellular accumulation of lipid peroxides, has played an important role in a wide range of diseases. Acute lung injury is a critical illness caused by several reasons, and the mortality rate is high. With increasing research on the mechanism of acute lung injury, more evidence has shown that ferroptosis played an important role in the pathogenesis of acute lung injury. In this paper, we sorted the previous studies related to ferroptosis and found that all acute lung injury induced by ischemia-reperfusion, sepsis, radiation, drowning and oleic acid were involved in ferroptosis. We hope to provide a promising theoreticalbasis for the future diagnosis and treatment of acute lung injury by summarizing the mechanism of ferroptosis and its role in the pathogenesis of acute lung injury.

Abstract Background Post-mortem animal predation affects human corpses in various ways. Lesions are a characteristic of the type of terrestrial or aquatic predators. These lesions can be misinterpreted and may be challenging for the forensic pathologist. Different species in freshwater cause different types of lesions depending on their feeding habits. There is a paucity in the literature about post-mortem lesions caused by freshwater animals. Case presentation A 24-year-old man had accidentally drowned while fishing in the River Cauvery. His body was recovered after 3 days. Though the cause of death was drowning, post-mortem animal activity was observed during autopsy, and a live juvenile crab was also found along with the body. Distinct post-mortem lesions caused by decapods Oziotelphusa wagrakarowensis and small fishes Hypselobarbus dubius and Dawkinsia arulius are described. Conclusions Aquatic predators and their activity on the corpse are different from that of terrestrial predators. Knowledge of the local fauna is required to correlate the lesions on the body to the predator.

Abstract Background Drowning is a leading cause of unintentional injury-related death for toddlers within the USA. Keeping toddlers within arm’s reach while swimming is recommended, yet many caregivers do not. Possibly, caregivers’ attitudes are shaped by their expectations about whether they could quickly save a child. The aims of this study are to 1) explore caregivers’ views of arm’s reach pool supervision in various scenarios and 2) understand whether perceptions of arm’s reach pool supervision are impacted by the caregiver’s self-reported capability to swim the length of a standard pool. Results Caregivers generally showed agreement with arm’s reach pool supervision; however, arm’s reach supervision was viewed as less necessary when a toddler was in shallow water, wearing a flotation device, or with an older child or teen. There was a significant effect of caregiver swimming capability on perceptions of arm’s reach pool supervision, with non-swimmers and the strongest swimmers showing more positive perceptions of arm’s reach pool supervision than caregivers reporting poor swimming capability. Female caregivers showed significantly more agreement with arm’s reach pool supervision compared with male caregivers. Grandparents and parents showed significantly more agreement with arm’s reach pool supervision than siblings. Conclusions Caregivers’ views about what constitutes appropriate supervision are impacted by gender, the relationship to the toddler, and the caregiver’s swimming capability. Findings suggest that a caregiver’s ability to offer close supervision or respond in an emergency may influence their attitudes about what constitutes appropriate supervision. Caregivers may view arm’s reach pool supervision as less necessary when additional layers of protection are in place.

Abstract Background Drowning is a serious worldwide and preventable injury problem, especially in low- and middle-income countries (LMICs). The aim of this paper is to draw on the results of semi-structured interviews with witnesses, family members and friends of persons involved in fatal and nonfatal drowning incidents to describe the circumstances of drowning in both lakeside and non-lakeside districts and to identify potential contextually appropriate interventions for drowning prevention and surveillance in Uganda. Methods The findings presented in this study were based on data collected from study participants selected through purposive sampling comprising 324 individual face-to-face interviews with drowning witnesses, family members, friends of and survivors of drowning and ten (10) focus group discussions held with community members in 14 districts in Uganda. Data analysis was done using the Framework Analysis Approach with the aid of the Microsoft Atlas ti software (version 8) program. Results The study results reveal a range of circumstances under which drowning occurs in Uganda, poor record keeping of drowning incidents, fear of reporting drowning incidences to the authorities, challenges in preventing drowning and proposed strategies for mitigating the problem. Conclusions This study found that there is no specialized record keeping system for drowning cases in Uganda and where such records are kept, the system is entirely manual (in hard copy form) with no electronic storage of data. Secondly, the drowning cases reported to police posts and stations in various parts of the country are not transmitted to the district headquarters and national database. These and other conclusions not only provide valuable insights into understanding of drowning circumstances but also the key policy and programme interventions for water-based economic activities such as fishing and public water transportation in Uganda and other LMICs.

Resumen: Introducción: el ideario popular, la diseminación a través de redes sociales o la «costumbre» han propiciado diversos mitos sobre el ahogamiento y los incidentes acuáticos que no están basados en evidencias y pueden tener efectos colaterales o limitan la comprensión de este fenómeno. El objetivo de este trabajo ha sido analizar el origen de los mitos más frecuentes relacionados con los incidentes acuáticos y ofrecer una perspectiva científica para su refutación. Materiales y métodos: doce expertos de las Ciencias de la Salud mediante un grupo nominal realizaron el cribado de conceptos en 3 fases: 1ª revisión literatura científica en PubMed en la que se abordasen conceptos erróneos u obsoletos relacionados a los incidentes en entornos acuáticos, 2ª el grupo elaboró un listado de 16 ítems susceptibles de analizar y 3ª se seleccionaron por consenso los mitos considerados más relevantes. Resultados: mediante consenso de expertos y las evidencias disponibles, 10 ítems fueron identificados como potenciales generadores de conceptos erróneos o mitos: el «corte de digestión», el uso de flotadores para prevenir el ahogamiento, hiperventilar antes de bucear, las implicaciones de la bandera roja en las playas, el proceso de ahogamiento, la principal función de los socorristas, orinar sobre picaduras de medusa, la terminología sobre ahogamiento y la reanimación de ahogados. Conclusión: en el ámbito del ahogamiento se sigue utilizando terminología obsoleta y existen creencias populares erróneas que deberían ser actualizadas y desmitificadas, ya que esto podría contribuir a disminuir la incidencia del ahogamiento y sus secuelas. Abstract: Introduction: Popular ideology, dissemination by social networks or the “custom” have fostered numerous myths about drowning and aquatic incidents that are not based on evidence and may be harmful or limit the understanding of this phenomenon. The aim of this paper is to analyze the origin of the most frequent myths related to aquatic incidents and to offer a scientific perspective for their refutation. Materials and methods: Twelve experts in the health sciences by means of a nominal group carried out the screening of concepts in three phases: 1st review of scientific literature in PUBMED in which erroneous or obsolete concepts related to incidents in aquatic environments were addressed, 2nd phase the nominal group elaborated an initial list of 16 items to be analyzed, 3rd phase the final list was refined to 1 by universal consensus of the nominal group. Results: Through expert consensus and available evidence, ten items were identified as potential generators of misconceptions or myths: the “digestion cut-off”, the use of floats to prevent drowning, hyperventilating before diving, the implications of the red flag on beaches, the drowning process, the main role of lifeguards, urinating on jellyfish stings, drowning terminology, and resuscitation of drowned persons. Conclusion: In the field of drowning, obsolete terminology continues to be used and there are erroneous popular beliefs that should be updated and demystified, as this could contribute to reduce the incidence of drowning and its sequelae.

Background: Home hot-tub bathing substantially increases drowning mortality rates among older adults in Japan. Previous laboratory studies on hemodynamic responses during hot-tub bathing have been inconsistent depending on the thermal conditions. Furthermore, real-world hemodynamic changes that occur during bathing remain poorly understood. This study investigated the association between individual thermal states and hemodynamic parameters during hot-tub bathing among community-dwelling older adults. Methods: In this cross-sectional study conducted between January 2016 and April 2019, which involved 1,479 older adults (median [range] age, 68 [40–90] years), skin temperature on the abdominal surface was measured every minute. Ambulatory blood pressure and pulse rate were recorded at 15-min intervals for 24 h. Participants underwent simultaneous living room temperature measurements in their homes, and the time and methods of bathing were recorded. Associations between skin temperature and hemodynamic parameters during bathing and between the pre-bath living room temperature and in-bath maximum proximal skin temperature were evaluated using mixed-effects and linear regression models, respectively. Results: A 1 °C increase in skin temperature was significantly associated with a 2.41 mmHg (95% confidence interval [CI]: 2.03–2.79) increase in systolic blood pressure and a 2.99 bpm (95% CI: 2.66–3.32) increase in pulse rate, after adjusting for potential confounders, including age, sex, body mass index, antihypertensive medication use, dyslipidemia, diabetes, and living room and outdoor temperatures. Significant interactions were not observed between sex and skin temperature in relation to systolic blood pressure and pulse rate (P = 0.088 and 0.490, respectively). One standard deviation lower living room temperature before bathing was significantly associated with a 0.41 °C (95% CI: 0.35–0.47) higher maximum skin temperature during bathing. Conclusions: Our findings suggest that pre-bath cold exposure may increase the skin temperature during hot-tub bathing, possibly resulting in excessive hemodynamic changes. This provides a framework for future interventions that utilize pre-bath thermal conditions and bathing environments to prevent bath-related deaths.

Hypercalcemia is generally caused by primary hyperparathyroidism, malignancies, and drugs. Herein, we report a case of severe hypercalcemia due to drowning in hot springs. A 55-year-old woman was found floating in a public bath at a hotel and was admitted to a nearby hospital. The patient was intubated because of hypoxia and shock, and noradrenaline was titrated. Computed tomography revealed bilateral aspiration pneumonia. Blood tests revealed hypercalcemia (serum total calcium [Ca]: 18.7 mg/dL). Hyperparathyroidism, malignancy, and drug-related factors were ruled out as the causes of hypercalcemia. In addition, the public bath in which the patient drowned contained high concentrations of Ca. We concluded that the reason for hypercalcemia was accidental ingestion of the hot spring water containing a high concentration of Ca through the gastrointestinal tract. In the case of drowning and hypercalcemia, the cause may be clarified by examining the components that were accidentally swallowed.

Drowning is a process of a severe respiratory disorder due to complete or partial immersion in a liquid medium. There are 5 types of drownings: true (aspiration), asphyxial, syncopal, hyperventilation and sudden death on the water. The clinical lecture studies the pathophysiological features of each type of drowning, treatment for each of them, measures to rescue a drowning victim and prevention of drowning.

Abstract Introduction Drowning is an under-recognised public health threat and a leading cause of injury-related mortality and morbidity. However, in many countries, including Turkey, limited data impair understanding of drowning burden and Global Burden of Disease (GBD) Study drowning estimates (defined using International Classification of Diseases [ICD] codes W65–74) do not include flood-related deaths (X38) and water transportation related drownings (V90, V92). A lack of accessible and reliable country-level data impacts a country’s ability to develop appropriate drowning prevention interventions and measure efficacy. This retrospective population-based study aimed to explore differences between two datasets in fatal drowning in Turkey between 2013 and 2019. Methods National, all-age data on fatal drownings (restrictive definition: ICD-10 codes W65–74) were sourced from the Turkish Statistical Institute (TurkStat) and the Global Burden of Disease (GBD) study. In addition, a broader definition of drowning including water transport, flood-related deaths and drowning due to undetermined intent (ICD-10 codes W65–74, V90, V92, X38, Y21, T751) were sourced from TurkStat. Numeric and percentage differences in number of drowning deaths were calculated overall and by sex, age group and death year. Chi square (p

The application of the Haddon matrix in identifying drowning prevention solutions in the north of Iran is necessary. We dealt with drownings on three levels of prevention including before, during, and after the injury in northern Iran (Guilan province). This study aimed to investigate the use of Haddon's matrix in preventing three-level drowning cases before, during, and after the accident in the north of Iran. This qualitative study consisted of 9 focus groups with a sample size of 78 people including 48 nursing staff, 21 emergency medicine specialists, and 30 people from non-medical personnel (local community leaders, executive officials of relevant organizations, lifeguards, staff working in health centers, and families of victims). All group discussions were recorded and the questions were based on the focus group table. According to Haddon's table of results, the major risk group was the young and adolescent boys and more in the area of neglect in culture-building and education. In this study, the role of factors was investigated separately and the necessary solutions were presented that can be used as a scientific and practical basis to achieve the main goal of drowning prevention. These strategies require cross-sectoral collaboration, which seems to be a strong interaction with a greater focus on major risk groups to address deficiencies and prevent the recurrence of potential accidents. The study aimed to investigate the use of Haddon's matrix in the prevention of three-level drowning cases before the event, during the event, and after the event in northern Iran.

Objectives: The International Liaison Committee on Resuscitation, in collaboration with drowning researchers from around the world, aimed to review the evidence addressing seven key resuscitation interventions: 1) immediate versus delayed resuscitation; (2) compression first versus ventilation first strategy; (3) compression-only CPR versus standard CPR (compressions and ventilations); (4) ventilation with and without equipment; (5) oxygen administration prior to hospital arrival; (6) automated external defibrillation first versus cardiopulmonary resuscitation first strategy; (7) public access defibrillation programmes. Methods: The review included studies relating to adults and children who had sustained a cardiac arrest following drowning with control groups and reported patient outcomes. Searches were run from database inception through to April 2023. The following databases were searched Ovid MEDLINE, Pre-Medline, Embase, Cochrane Central Register of Controlled Trials. Risk of bias was assessed using the ROBINS-I tool and the certainty of evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation. The findings are reported as a narrative synthesis. Results: Three studies were included for two of the seven interventions (2,451 patients). No randomised controlled trials were identified. A retrospective observational study reported in-water resuscitation with rescue breaths improved patient outcomes compared to delayed resuscitation on land (n = 46 patients, very low certainty of evidence). The two observational studies (n = 2,405 patients), comparing compression-only with standard resuscitation, reported no difference for most outcomes. A statistically higher rate of survival to hospital discharge was reported for the standard resuscitation group in one of these studies (29.7% versus 18.1%, adjusted odds ratio 1.54 (95% confidence interval 1.01–2.36) (very low certainty of evidence). Conclusion: The key finding of this systematic review is the paucity of evidence, with control groups, to inform treatment guidelines for resuscitation in drowning.

The aim of this study was to analyze the rescues carried out by surfers from Portugal and Spain, their knowledge of rescue and resuscitation and their perception and risk behavior while surfing. An online survey was conducted in 2048 surfers from Portugal and Spain, with questions regarding the demographic characteristics, experience, perception and risk behavior of the surfers; rescues attended by the surfers and surfer's knowledge and experience in rescue and resuscitation. Concerning the number of rescues carried out by surfers, 78.5% of the participants had to carry out at least one rescue in their lifetime. A significant association was found between the years of surfing experience, the surfing level and the number of rescues carried out (p

Drowning has been identified as the cause of over 2.5 million preventable deaths globally in the past decade. Lower- and middle-income countries in Asia have recorded the highest numbers of drowning worldwide and children seem particularly vulnerable. Drowning is a complex phenomenon informed by multiple interacting factors, and the majority of deaths occur in natural environments such as ponds, ditches, rivers and oceans. Any potential drowning prevention strategy should acknowledge the important relationships that are created between individuals and their environment in water safety education. In this article, we share how the ecological dynamics theoretical perspective can help inform our understanding of drowning prevention. First, we review recent drowning prevention recommendations provided by the World Health Organization (WHO). Next, we discuss how well WHO's recommendations align with the principles of ecological dynamics. It is acknowledged that in many Asian countries, there are considerable challenges to delivering WHO's drowning prevention interventions. Teaching children basic swimming, water safety and self-rescue skills remains the most practical means to prevent drowning. The relevant scale of analysis for understanding behaviour is the individual-environment relationship. Specifically, the relative fit between these components may dictate how well water safety skills are learnt. Considerations such as installing barriers and adequate supervision around water can be scaffolded alongside an understanding of affordances in the context of water safety. We conclude that water safety education informed by an ecological dynamics approach is an effective partnership to help tackle the drowning pandemic.

Recently, the drowning cases of human beings are at an alarming rate. The current work presents a dedicated review on U-WRB for human rescue operations subjected to drowning. The review from year 1996 to 2018 highlights the key factors such as advantages and limitations of the developed U-WRB’s. Having completed the review, the work further proposes new research pathways that could be beneficial to the scientific community living in the new norm; COVID-19 where minimal contact between humans areof concern when it comes to human rescue operations. Possible new research pathways include but not limited to the type of sensors used, material selection, incorporation of state-of-the-art attachments to the U-WRB and customizable attachments to the main unit based on a given real time rescue operation are proposed.

ObjectiveTo examine the effect of improving diatom DNA extraction by glass bead - vortex oscillation method.MethodsThe DNeasy PowerSoil Pro kit was used as control, two plant DNA extraction kits with different principles （New Plant genomic DNA extraction kit and Plant DNA Isolation kit） and one whole blood DNA extraction kit （whole blood genomic DNA extraction kit） were selected to extract diatom DNA from lung tissue and water sample of the same drowning case. The combination of mass ratio of glass beads with different sizes and vortex oscillation time was designed, and the optimal DNA extraction conditions were selected with the addition of glass beads oscillation. The extracted products of the conventional group and the modified group were directly electrophoretic and detected by diatom specific PCR. Finally, all the extracts were quantified by qPCR, and the Ct values of different groups were statistically analyzed.ResultsWhen the frequency of vortex oscillation was 3 000 r/min, the optimal combination of DNA extraction was vortex oscillation for 4 min, and the mass ratio of large glass beads to small glass beads was 1∶1. The DNeasy PowerSoil Pro kit was used as a reference, and the Ct value of 10 mL water sample was greater than that of 0.5 g tissue. The Ct values of the other three kits used for plant DNA extraction decreased after the glass beads-vortex oscillation method was used, and the Ct values of the tissues before and after the improvement were statistically significant （P

ObjectiveTo establish a diatom database by analyzing the quatity, species distribution and differences of diatom in water samples of the whole navigable sections of the Beijing-Hangzhou Grand Canal， to provide a reference for the inference of the drowning site.MethodsWater samples were collected at 22 sites in the navigable sections of the Beijing-Hangzhou Grand Canal （Jining section to Yangzhou Section）， and the diatoms at each site were qualitatively and quantitatively analyzed by using graphite digestion-scanning electron microscopy.ResultsSampling site T （Laohuaijiang River Line, Gaoyou City, Yangzhou City, Jiangsu Province） had the highest number of diatoms, while sampling site O （Siyang County, Suqian City, Jiangsu Province） had the lowest number of diatoms, with a large gap of 68 times. At sampling site Q （Jiangpu District, Huaian city, Jiangsu Province）, there were 19 species of diatoms. The sampling site O had the least diatoms, with 7 species. There were no significant differences in species evenness and species diversity at each sampling site （P>0.05）. Some sampling sites have characterized diatoms, such as Caloneis at station A （Taibai Lake, Weishan County, Shandong Province）, Rhoicosphenia at station B （Nanyang Town, Weishan County, Shandong Province）, Amphora at station I （Taierzhuang District, Zaozhuang City, Shandong Province） and Epithemia at station J （Pizhou 310 national highway, Xuzhou City, Jiangsu Province）.ConclusionThe species richness of diatoms gradually increased from north to south. Diatom species richness and species diversity might be higher in areas with complex environments and large population flow. Climate type has a certain influence on the distribution of diatoms.

ObjectiveTo study whether diatoms can enter the body through the lymphatic system of the digestive tract.MethodsTwenty experimental rabbits were divided into the test group and the control group randomly, and intragastric administration was performed with 20 mL water sample from the Pearl River and 20 mL ultrapure water, respectively. After 30 min, lymph, lungs， livers and kidneys were extracted for the diatom test. The concentration, size and type of diatoms were recorded.ResultsThe concentration of diatoms of the test group was higher than that of the control group （P

ObjectiveTo select four algorithms with relatively balanced complexity and accuracy among deep learning image classification algorithms for automatic diatom recognition, and to explore the most suitable classification algorithm for diatom recognition to provide data reference for automatic diatom testing research in forensic medicine.MethodsThe “diatom” and “background” small sample size data set （20 000 images） of digestive fluid smear of corpse lung tissue in water were built to train, validate and test four convolutional neural network （CNN） models, including VGG16, ResNet50, InceptionV3 and Inception-ResNet-V2. The receiver operating characteristic curve （ROC） of subjects and confusion matrixes were drawn, recall rate, precision rate， specificity， accuracy rate and F1 score were calculated， and the performance of each model was systematically evaluated.ResultsThe InceptionV3 model achieved much better results than the other three models with a balanced recall rate of 89.80%, a precision rate of 92.58%. The VGG16 and Inception-ResNet-V2 had similar diatom recognition performance. Although the performance of diatom recall and precision detection could not be balanced, the recognition ability was acceptable. ResNet50 had the lowest diatom recognition performance, with a recall rate of 55.35%. In terms of feature extraction, the four models all extracted the features of diatom and background and mainly focused on diatom region as the main identification basis.ConclusionIncluding the Inception-dependent model, which has stronger directivity and targeting in feature extraction of diatom. The InceptionV3 achieved the best performance on diatom identification and feature extraction compared to the other three models. The InceptionV3 is more suitable for daily forensic diatom examination.

ObjectiveTo retrospectively analyze diatom test cases of corpses in water and discuss the value of quantitative analysis of diatoms in the diagnosis of drowning.MethodsA total of 490 cases of water-related death were collected. They were divided into drowning group and postmortem immersion group according to the cause of death. Diatoms in lung, liver, kidney tissue and water sample were analyzed quantitatively by microwave digestion-vacuum filtration-automated scanning electron microscopy （MD-VF-Auto SEM） method. The ratios of content of diatoms in lung tissue and water sample （CL/CD） were calculated.ResultsThe results of diatom test for three organs （lung, liver and kidney） were all positive in 400 cases （85.5%）; the content of diatom in lung, liver, kidney tissues, and water samples of drowning group were （113 235.9±317 868.1）, （26.7±75.6）, （23.3±52.2） and （12 113.3±21 760.0） cells/10 g, respectively; the species of diatom were （7.5±2.8）, （2.6±1.9）, （2.9±2.1） and （8.9±3.0） types, respectively; the CL/CD of drowning group and postmortem immersion group were （100.6±830.7） and （0.3±0.4）, respectively.ConclusionQuantitative analysis of diatoms can provide supportive evidence for the diagnosis of drowning, and the parameter CL/CD can be introduced into the analysis to make a more accurate diagnosis of drowning.

ObjectiveTo explore the application value of virtual autopsy to obtain key evidence information on drowned corpses and its application value of virtual autopsy in the diagnosis of drowning.MethodsIn this study, 7 corpses were selected as the research objects. The image data of corpses were collected by computed tomography （CT） before conventional autopsy. The characteristics of corpses were observed through image reading, combined with virtual measurement indexes, and compared with 15 non-drowned corpses.ResultsThe postmortem CT of drowning showed the more fluid in respiratory tract than the non-drowning， and ground-glass opacities in the lung. The statistical volume of fluid in the sinus （maxillary sinus and sphenoid sinus） was （10.24±4.70） mL in drowning cases and （2.02±2.45） mL in non-drowning cases. The average CT value of fluid in the sinus， left atrial blood and gastric contents in drowning cases were （15.91±17.20）, （52.57±9.24） and （10.33±12.81） HU， respectively， which were lower than those in non-drowning cases （P

Diatom detection is an important method for identifying drowning and throwing corpses after death and inferring the drowning sites in forensic examination of corpses in water. In recent years,high-throughput sequencing technology has achieved rapid development and has been widely used in research related to diatom taxonomic investigations. This paper reviews the research status and prospects of high-throughput sequencing technology and its application in forensic diatom detection.

ObjectiveTo study the annual variation of diatoms in Zhangweixin River, to provide theoretical support by using diatom examination to estimate the time and place of the corpse entering water, and to establish a diatom database.MethodsSamples were taken from 4 sampling sites in Decheng section of Zhangweixin River for 12 consecutive months. Non-metric multi-dimensional scaling （NMDS） analysis was performed on the species and content of diatom samples. Based on the sampling site of Tianqu Road, Sprensen similarity coefficient analysis was conducted with the data of other 3 sites in Decheng section and Leling section of Zhangweixin River and Ningjin section in previous studies.ResultsThe number of diatom species was positively correlated with diatom content. The average diatom content in different months ranged from 1 054 to 13 041/10 mL, and the species composition ranged from 8 to 16, with differences in dominant species. The similarity coefficient of diatom species within 2 km were all higher than 0.956 52， which could not be distinguished effectively. The similarity coefficients of Leling section and Ningjin section were 0.736 84 and 0.588 24 respectively, which could be effectively distinguished.ConclusionThe species and content of diatom vary in different months in Zhangweixin River, and the composition of diatom species is different in different basins, which can provide reference for estimating the time and place of the corpse entering water in the river.

ObjectiveTo study the phenomenon of pulmonary hypostasis in corpses of various causes of death， and to explore the potential value of this phenomenon in assisting forensic pathological diagnosis of drowning.MethodsA total of 235 cases with clear cause of death through systematic autopsy were collected from January 2011 to June 2021 in Guangzhou. According to the location of body discovery, the cases were divided into the water body group （97 cases） and the non-water body group （138 cases）, and the water body group was further divided into the water drowning group （90 cases） and the water non-drowning group （7 cases）. Non-water body group was further divided into the non-water drowning group （1 case） and the non-water non-drowning group （137 cases）. Three senior forensic pathologists independently reviewed autopsy photos to determine whether there was hypostasis in the lungs. The detection rate of pulmonary hypostasis was calculated.ResultsThe detection rate of pulmonary hypostasis in the water drowning group （90 cases） was 0， and the negative rate was 100%. The detection rate of pulmonary hypostasis in the water non-drowning group （7 cases） was 100% and the negative rate was 0. The detection rate of pulmonary hypostasis in the water body group and in the non-water body group （after excluding 2 cases, 136 cases were calculated） was 7.22% and 87.50%， respectively. There were statistically significant differences in the detection rate of pulmonary hypostasis between water body group and non-water body group, and between water drowning group and water non-drowning group （P

Diatom test is the main laboratory test method in the diagnosis of drowning in forensic medicine. It plays an important role in differentiating the antemortem drowning from the postmortem drowning and inferring drowning site. Artificial intelligence （AI） automatic diatom test is a technological innovation in forensic drowning diagnosis which is based on morphological characteristics of diatom, the application of AI algorithm to automatic identification and classification of diatom in tissues and organs. This paper discusses the morphological diatom test methods and reviews the research progress of automatic diatom recognition and classification involving AI algorithms. AI deep learning algorithm can assist diatom testing to obtain objective, accurate, and efficient qualitative and quantitative analysis results, which is expected to become a new direction of diatom testing research in the drowning of forensic medicine in the future.

Drowning is the death caused by asphyxiation due to fluid blocking the airway. In the practice of forensic medicine， it is the key to determine whether the corpse was drowned or entered the water after death. At the same time， the drowning site inference and postmortem submersion interval （PMSI） play an important role in the investigating the identity of the deceased, narrowing the investigation scope, and solving the case. Based on diatoms testing， molecular biology， imaging and artificial intelligence and other technologies， domestic and foreign forensic scientists have done relative research in the identification of the cause of death， drowning site inference and PMSI， and achieved certain results in forensic medicine application. In order to provide a reference for future study of bodies in the water， this paper summarizes the above research contents.

ObjectiveTo compare the application effect of microwave digestion - vacuum filtration - automated scanning electron microscopy （MD-VF-Auto SEM） method and plankton gene multiplex PCR system in the diagnosis of drowning.MethodsLung, liver and kidney tissue of 10 non-drowning cases and 50 drowning cases were prepared for further MD-VF-Auto SEM method analysis and plankton gene multiplex PCR system analysis. The positive detection rate of the two methods in each tissue was calculated.ResultsThe positive rate of the MD-VF-Auto SEM method detecting diatoms in drowning cases was 100%, and few diatoms were detected in the liver and kidney tissues of 6 non-drowning cases. By using the plankton gene multiplex PCR system, the diatom positive rate of drowning cases was 84%, and all the non-drowning cases were negative. There were significant differences in the positive rate of the liver, kidney tissues between MD-VF-Auto SEM method and plankton gene multiplex PCR system （P0.05）.ConclusionMD-VF-Auto SEM method is more sensitive than plankton gene multiplex PCR system in diatom test. But the plankton gene multiplex PCR system can also detect plankton other than diatoms. Combination of the two methods can provide a more reliable basis for the diagnosis of drowning.

ObjectiveTo explore the research hotspots and development trends of the field of forensic drowning from 1991 to 2020 by bibliometrics methods.MethodsBased on Web of Science， CNKI database， Wanfang Data knowledge service platform， python 3.9.2， CiteSpace 5.8.R3, Gephi 0.9.2, etc. were used to analyze the publishing trends， countries/regions， institutions， authors and topics of the study on drowning.ResultsA total of 631 English literature were obtained， including 59 articles from Chinese authors， and 386 Chinese literature were obtained. The Chinese and English journals with the largest number of related literatures were Chinese Journal of Forensic Science （80 articles） and Forensic Science International （106 articles）， respectively. Japan published the most articles in English， and China ranked third. Osaka City Univ （Japan，28 articles） published the most English articles，and Guangzhou Forens Sci Inst （China，22 articles） ranked second. Among Chinese literature， Guangzhou Forens Sci Inst （32 articles） published the most. The topic analysis of Chinese and English literature showed that diatom examination， virtual autopsy， postmortem biochemical examination， the nature of death， and postmortem submersion interval were the hot spots of current research， but English literature had more studies on new technologies and methods， while Chinese literature was more inclined to practice， application and experience summary.ConclusionThe number of literature in forensic medicine on drowning is relatively stable. The scope of international and domestic collaborations in this field is still limited. The automated examination of diatoms， the establishment of diatom DNA barcodes and virtual autopsy will be the most important research hotspots in the coming period and are expected to achieve breakthroughs in drowning diagnosis， drowning location inference， postmortem submersion interval estimation， etc.

ObjectiveTo study the relationship between water temperature and floating time of aquatic cadavers， providing a reference for more precise positioning and searching for floating corpses.MethodsThe floating model of guinea pig after drowning at 17-30 ℃ was established, and the floating times of carcasses were recorded. The collected data of 32 floating corpse cases in the Pearl River were sorted out and analyzed according to the floating time of corpses corresponding to each degree of water temperature. The relationship models between water temperature and the floating time of guinea pig carcass, and between that and the floating time of real cases were established.ResultsThe floating time of the cadaver was negatively correlated with water temperature. The power function fitting equation of the relationship between floating time and water temperature of guinea pig carcass was y=1×1015x-10.530（R2=0.871, P

ObjectiveTo explore the application values of diatom artificial intelligence （AI） search system in the diagnosis of drowning.MethodsThe liver and kidney tissues of 12 drowned corpses were taken and were performed with the diatom test, the view images were obtained by scanning electron microscopy （SEM）. Diatom detection and forensic expert manual identification were carried out under the thresholds of 0.5, 0.7 and 0.9 of the diatom AI search system, respectively. Diatom recall rate， precision rate and image exclusion rate were used to detect and compare the efficiency of diatom AI search system.ResultsThere was no statistical difference between the number of diatoms detected in the target marked by the diatom AI search system and the number of diatoms identified manually （P>0.05）; the recall rates of the diatom AI search system were statistically different under different thresholds （P