The use of non-uniform drowning terminology: a follow-up study

Conceptual definition for drowning prevention: a Delphi study

BACKGROUND

Expanding support for drowning prevention is evidenced by interlinked Resolutions at the United Nations (2021) and World Health Assembly (2023). While progress has accelerated, a universally agreed definition for drowning prevention remains absent. Here, we aim to develop a conceptual definition of drowning prevention using the Delphi method.

METHODS

First, we conducted a document review to guide our development and consensus-building process. Then, we formed an advisory group and recruited participants with diverse expertise to contribute to Delphi-method surveys. In the first round, participants selected from draft concepts to build a definition and delineate between the terms drowning prevention and water safety. In the second round, we presented a codeveloped definition, and three statements based on first-round findings. We then sought participant feedback where ≥70% support was considered consensus-based agreement.

RESULTS

Participants (n=134) were drawn from community (7.46%), policy (26.87%), research (40.30%) and technical backgrounds (25.37%), and low-income and middle-income countries (38.06%). In the first- round, half (50.74%) disagreed with the proposition that drowning prevention was synonymous to water safety, while 40.30% agreed. The second- round achieved consensus-based agreement (97.27%) for the definition: Drowning prevention is defined as a multidisciplinary approach that reduces drowning risk and builds resilience by implementing evidence-informed measures that address hazards, exposures and vulnerabilities to protect an individual, community or population against fatal and non-fatal drowning.

CONCLUSION

The Delphi method enabled the codevelopment of our conceptual definition for drowning prevention. Agreement on the definition forms the basis for strengthened multisectoral action, and partnerships with health and sustainable development agendas. Defining drowning prevention in terms of vulnerability and exposure might increase focus on social determinants and other upstream factors critical to prevention efforts.

Danish Drowning Formula for identification of out-of-hospital cardiac arrest from drowning

BACKGROUND

Accurate, reliable, and sufficient data is required to reduce the burden of drowning by targeting preventive measures and improving treatment. Today's drowning statistics are informed by various methods sometimes based on data sources with questionable reliability. These methods are likely responsible for a systematic and significant underreporting of drowning. This study's aim was to assess the 30-day survival of patients with out-of-hospital cardiac arrest (OHCA) identified in the Danish Cardiac Arrest Registry (DCAR) after applying the Danish Drowning Formula.

METHODS

This nationwide, cohort, registry-based study with 30-day follow-up used the Danish Drowning Formula to identify drowning-related OHCA with a resuscitation attempt from the DCAR from January 1st, 2016, through December 31st, 2021. The Danish Drowning Formula is a text-search algorithm constructed for this study based on trigger-words identified from the prehospital medical records of validated drowning cases. The primary outcome was 30-day survival from OHCA. Data were analyzed using multiple logistic regression.

RESULTS

Drowning-related OHCA occurred in 374 (1%) patients registered in the DCAR compared to 29,882 patients with OHCA from other causes. Drowning-related OHCA more frequently occurred at a public location (87% vs 25%, p < 0.001) and were more frequently witnessed by bystanders (80% vs 55%, p < 0.001). Both 30-day and 1-year survival for patients with drowning-related OHCA were significantly higher compared to OHCA from other causes (33% vs 14% and 32% vs 13%, respectively, p < 0.001). The adjusted odds ratio for 30-day survival for drowning-related OHCA and other causes of OHCA was 2.3 [1.7-3.2], p < 0.001. Increased 30-day survival was observed for drowning-related OHCA occurring at swimming pools compared to public location OHCA from other causes with an OR of 11.6 [6.0-22.6], p < 0.001.

CONCLUSIONS

This study found higher 30-day survival among drowning-related OHCA compared to OHCA from other causes. This study proposed that a text-search algorithm (Danish Drowning Formula) could explore unstructured text fields to identify drowning persons. This method may present a low-resource solution to inform the drowning statistics in the future.

REGISTRATION

This study was registered at ClinicalTrials.gov before analyses (NCT05323097).

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.