Brain resuscitation in the drowning victim

Drowning

Drowning is responsible for considerable morbidity and mortality worldwide, and it is estimated that 90% of drownings are preventable. Drowning is defined as "the process of experiencing respiratory impairment from submersion/immersion in liquid." Emergency providers should focus on airway management and rapid delivery of oxygen to interrupt the drowning process and improve patient outcomes. Patients with minimal or no symptoms do not require any specific diagnostic workup, aside from physical examination and 4 to 6 hours of observation prior to discharge. Patients with more severe symptoms may present with rales and foamy secretions, and should be managed with high-concentration oxygen and positive airway pressure.

Wilderness Medical Society Clinical Practice Guidelines for the Treatment and Prevention of Drowning: 2024 Update

The Wilderness Medical Society convened a panel to review available evidence supporting practices for acute management of drowning in out-of-hospital and emergency care settings. Literature about definitions and terminology, epidemiology, rescue, resuscitation, acute clinical management, disposition, and drowning prevention was reviewed. The panel graded available evidence supporting practices according to the American College of Chest Physicians criteria and then made recommendations based on that evidence. Recommendations were based on the panel's collective clinical experience and judgment when published evidence was lacking. This is the second update to the original practice guidelines published in 2016 and updated in 2019.

Long-Term Neurocognitive Outcomes in Pediatric Nonfatal Drowning: Results of a Family Caregiver Survey

BACKGROUND

Drowning is a leading cause of brain injury in children. Long-term outcome data for drowning survivors are sparse. This study reports neurocognitive outcomes for 154 children hospitalized following drowning.

METHODS

A survey for parent caregivers was distributed online. Likert scale items assessed 10 outcome variables in four domains: motor (three), perception (three), language (three), and social/emotional (one). Cluster analysis, outcome relative risk, and descriptive statistics were applied.

RESULTS

Of 208 surveys received, 154 met inclusion criteria. Coma was the most common admission status (n = 137). Cluster analysis identified three outcome groups: Mild (n = 39), Moderate (n = 75), and Severe (n = 40). Motor impairment with cognitive and perceptual sparing (deefferentation) was present in Moderate (P < 1 × 10-26) and Severe (P < 1 × 10-12) but absent in Mild. Locked-in state was endorsed in both Moderate (83%) and Severe (70%). The strongest predictor of good outcome (Mild) was hospitalization with no medical intervention (relative risk [RR] = 6.7). Responsivity on admission (RR = 4.2) or discharge (RR = 12.22) also predicted good outcome. In-hospital prognostication and counseling predicted outcome weakly (RR = 1.3) or not at all.

CONCLUSIONS

Long-term outcomes in pediatric drowning ranged widely. Overall, motor impairments exceeded perceptual or cognitive (P < 1 × 10-18), with "locked-in state" endorsed in most (93 of 154). The strongest predictors of good outcome were the lack of necessity for interventions and responsivity on admission or discharge. The eponym "Conrad syndrome" is proposed for locked-in state following nonfatal drowning in children.

Unveiling Lethal Risks Lurking in Hot Tub Baths: A Review of Tragic Consequences

Heat therapy, including saunas, jacuzzi, and hot tub bathing, has gained global popularity. However, the escalating incidents of injuries and fatalities associated with hot tub activities are a significant public health concern. This study aims to comprehensively review and analyze the pathophysiological factors contributing to hot tub-related deaths, addressing the need for awareness and mitigation strategies. A comprehensive search of electronic databases, PubMed and Science Direct, was conducted to identify articles relevant to bath-related deaths. Eligible studies were exported to the Rayyan (Qatar Computing Research Institute, Qatar) software for data analysis. The data extracted from the 18 studies were compiled to elucidate the mechanisms underlying hot tub bath-related deaths and to advocate for the adoption of potential mitigation strategies and future directions to prevent such incidents in the future. The review revealed insights into the current trend of fatalities linked to hot tub bathing. A detailed analysis of pathophysiological aspects, encompassing hemodynamics, electrolyte disturbances, serum glucagon alterations, and the impact of alcohol and substance abuse during hot tub use, was conducted. Furthermore, we explored the effects of temperature and conducted a thorough discussion of postmortem evidence analysis concerning deaths related to bathtub usage. Finally, the paper discusses mitigation strategies to prevent fatalities attributed to hot tub bathing. In conclusion, our review highlights growing public health concerns surrounding injuries and fatalities related to hot tub activities. Through an examination of the incidence rates, pathophysiological factors, and proposed mitigation strategies, we provide crucial insights for enhancing safety and addressing the escalating risks associated with hot tub bathing.

A quest for an integrated management system of children following a drowning incident: A review of the literature

PURPOSE

Management of children following a drowning incident is based on specific interventions which are used in the prehospital environment, the emergency department (ED) and the Paediatric Intensive Care Unit (PICU). This paper presents a review of the literature to map and describe the management and interventions used by healthcare professionals when managing a child following a drowning incident. Of specific interest was to map, synthesise and describe the management and interventions according to the different clinical domains or practice areas of healthcare professionals.

DESIGN AND METHODS

A traditional review of the literature was performed to appraise, map and describe information from 32 relevant articles. Four electronic databases were searched using search strings and the Boolean operators AND as well as OR. The included articles were all published in English between 2010 and 2022, as it comprised a timeline including current guidelines and practices necessary to describe management and interventions.

RESULTS

Concepts and phrases from the literature were used as headings to form a picture or overview of the interventions used for managing a child following a drowning incident. Information extracted from the literature was mapped under management and interventions for prehospital, the ED and the PICU and a figure was constructed to display the findings. It was evident from the literature that management and interventions are well researched, evidence-informed and discussed, but no clear arguments or examples could be found to link the interventions for integrated management from the scene of drowning through to the PICU. Cooling and/or rewarming techniques and approaches and termination of resuscitation were found to be discussed as interventions, but no evidence of integration from prehospital to the ED and beyond was found. The review also highlighted the absence of parental involvement in the management of children following a drowning incident.

PRACTICE IMPLICATIONS

Mapping the literature enables visualisation of management and interventions used for children following a drowning incident. Integration of these interventions can collaboratively be done by involving the healthcare practitioners to form a link or chain for integrated management from the scene of drowning through to the PICU.

Case report: The physiology of a preventable tragedy -Near death in a hot tub

Hyperthermia in children is a known risk within enclosed vehicles. Exposure to an overheated hot tub poses a real risk in children due to unique pediatric physiology. Medical and aquatic professionals should understand the risk and mitigation strategies.

[Expert consensus on the prevention and treatment of drowning in children]

Drowning is a leading cause of accidental injury in children and has a great impact on family and society. The prevention and treatment of drowning is of great importance for reducing mortality rate. This consensus reviews the literature on the epidemiology, rescue, resuscitation, and acute clinical management and prevention of drowning. The panel determines the score of available evidence according to the criteria of Oxford Centre for Evidence-Based Medicine and then makes recommendations on evidence based on such criteria, so as to provide a basis for further reducing the mortality and disability rates caused by drowning.

Management for the Drowning Patient

Drowning is "the process of experiencing respiratory impairment from submersion or immersion in liquid." According to the World Health Organization, drowning claims the lives of > 40 people every hour of every day. Drowning involves some physiological principles and medical interventions that are unique. It occurs in a deceptively hostile environment that involves an underestimation of the dangers or an overestimation of water competency. It has been estimated that > 90% of drownings are preventable. When water is aspirated into the airways, coughing is the initial reflex response. The acute lung injury alters the exchange of oxygen in different proportions. The combined effects of fluid in the lungs, loss of surfactant, and increased capillary-alveolar permeability result in decreased lung compliance, increased right-to-left shunting in the lungs, atelectasis, and alveolitis, a noncardiogenic pulmonary edema. Salt and fresh water aspirations cause similar pathology. If the person is not rescued, aspiration continues, and hypoxemia leads to loss of consciousness and apnea in seconds to minutes. As a consequence, hypoxic cardiac arrest occurs. The decision to admit to an ICU should consider the patient's drowning severity and comorbid or premorbid conditions. Ventilation therapy should achieve an intrapulmonary shunt ≤ 20% or Pao₂:Fio₂ ≥ 250. Premature ventilatory weaning may cause the return of pulmonary edema with the need for re-intubation and an anticipation of prolonged hospital stays and further morbidity. This review includes all the essential steps from the first call to action until the best practice at the prehospital, ED, and hospitalization.

Outcomes of Extracorporeal Life Support Use in Accidental Hypothermia: A Systematic Review

BACKGROUND

Extracorporeal life support (ECLS) has been used in the treatment of accidental hypothermia with hemodynamic instability, with promising outcomes. This systematic review examines ECLS treatment of accidental hypothermia to assess outcomes.

METHODS

An electronic search was performed to identify articles reporting ECLS use for treatment of accidental hypothermia. Only reports describing patients aged more than 16 years after January 1, 2005, were included. Nineteen studies were identified comprising 47 patients. Demographic information, perioperative variables, and outcomes were extracted for analysis.

RESULTS

Median patient age was 48 years (interquartile range (IQR), 29 to 56), and 72.3% (34 of 47) were male. On presentation, median body temperature was 24.6°C (IQR, 22.2° to 26°C), median potassium level 4.3 mmol/L (IQR, 3.4 to 4.6 mmol/L), and median Glasgow Coma Scale score 3 (IQR, 3 to 7). Cardiac arrest occurred in 35 of 47 patients (74.5%). Median time to ECLS initiation from scene was 155 minutes (IQR, 113 to 245). Median ECLS duration was 18 hours (IQR, 4 to 27), with median rewarming rate of 2°C per hour (IQR, 1.5° to 4°). Median intensive care unit stay and hospital length of stay were 8 days (IQR, 2 to 16) and 17 days (IQR, 10 to 36), respectively. Inhospital mortality was 19.1% (9 of 47). Median discharge Glasgow Coma Scale score was 15 (IQR, 15 to 15) with minor long-term cognitive impairments noted in 6 of 47 patients (19.4%). Survival was significantly associated with potassium on presentation (P < .001), initial body temperature (P < .001), and ECLS rewarming rate (P < .001).

CONCLUSIONS

Extracorporeal life support is a viable cardiac support option for rewarming patients with accidental hypothermia, and initial potassium level, initial body temperature, and ECLS rewarming rate appear to be significantly associated with survival.

Outcomes of Bone Marrow-Derived Mononuclear Cell Transplantation for Patients in Persistent Vegetative State After Drowning: Report of Five Cases

Aim: Anoxic brain injury (ABI) due to non-fatal drowning may cause persistent vegetative state (VS) that is currently incurable. The aim of this paper is to present the safety and feasibility of autologous bone marrow-derived mononuclear cell (BMMNC) transplantation in five drowning children surviving in persistent VS. Methods: We used BMMNC as a novel candidate therapeutic tool in a pilot phase-I study for five patients affected by neurological sequelae after near-death drowning. Autologous BMMNCs were freshly isolated using Ficoll gradient centrifugation then infused intrathecally to five patients. The number of transplantation varied from two to four times depending on the motor function improvement of patient after transplantation. Clinical therapeutic effects were evaluated using gross motor function measure and muscle spasticity rating scales, cognitive assessments, and brain MRI before and after cell administrations. Results: Six months after BMMNC transplantation, no serious complications or adverse events were reported. All five patients displayed improvement across the major parameters of gross motor function, cognition, and muscle spasticity. Three patients displayed improved communication including the expression of words. In particular, one patient remarkably reduced cerebral atrophy, with nearly normal cerebral parenchyma after BMMNC transplantation. Conclusions: Autologous BMMNC transplantation for the treatment of children in persistent VS after drowning is safe, feasible, and can potentially improve motor function and cognition and reduce muscle spasticity. These results pave the way for a future phase II clinical trial to evaluate the efficacy of the therapy.

Wilderness Medical Society Clinical Practice Guidelines for the Treatment and Prevention of Drowning: 2019 Update

The Wilderness Medical Society convened a panel to review available evidence supporting practices for acute management and treatment of drowning in out-of-hospital and emergency medical care settings. Literature about definitions and terminology, epidemiology, rescue, resuscitation, acute clinical management, disposition, and drowning prevention was reviewed. The panel graded available evidence supporting practices according to the American College of Chest Physicians criteria and then made recommendations based on that evidence. Recommendations were based on the panel's collective clinical experience and judgment when published evidence was lacking. This is the first update to the original practice guidelines published in 2016.

Pediatric Post–Cardiac Arrest Care: A Scientific Statement From the American Heart Association

Successful resuscitation from cardiac arrest results in a post–cardiac arrest syndrome, which can evolve in the days to weeks after return of sustained circulation. The components of post–cardiac arrest syndrome are brain injury, myocardial dysfunction, systemic ischemia/reperfusion response, and persistent precipitating pathophysiology. Pediatric post–cardiac arrest care focuses on anticipating, identifying, and treating this complex physiology to improve survival and neurological outcomes. This scientific statement on post–cardiac arrest care is the result of a consensus process that included pediatric and adult emergency medicine, critical care, cardiac critical care, cardiology, neurology, and nursing specialists who analyzed the past 20 years of pediatric cardiac arrest, adult cardiac arrest, and pediatric critical illness peer-reviewed published literature. The statement summarizes the epidemiology, pathophysiology, management, and prognostication after return of sustained circulation after cardiac arrest, and it provides consensus on the current evidence supporting elements of pediatric post–cardiac arrest care.

Acute respiratory failure after drowning: a retrospective multicenter survey

OBJECTIVES

Despite the extensive literature on drowning, clinical data are still lacking on the best medical strategy to use. Acute respiratory failure (ARF) is the main component of drowning pathophysiology. The objectives of this multicenter study were to analyze the clinical course of drowning-related ARF patients and to describe the efficacy of the ventilatory strategies used.

METHODS

Medical records of drowned adult patients admitted in seven ICUs after prehospital emergency medical care during three consecutive summer periods were retrospectively analyzed.

RESULTS

Among the 126 patients (58±21 years) admitted, 38 patients with cardiac arrest at the scene were not analyzed, 26 received mechanical ventilation (MV), and 48 patients received noninvasive ventilation (NIV). Compared with patients placed under MV, the NIV patients presented a better initial neurological (Glasgow Coma Scale of 7±4 vs. 12±3, P<0.05) and hemodynamic status from the prehospital stage (mean arterial pressure of 77±18 vs. 96±18, P<0.001). With comparable ARF-related hypoxemia to MV, the NIV was maintained with success in 92% (44/48). Both MV and NIV were associated with rapid improvement of oxygenation and short ICU length of stay [3 (1-14) and 2 (1-7), respectively].

CONCLUSION

Despite the absence of recommendation for NIV use in case of drowning-related ARF, this technique was often used with safety and efficacy. The decision for NIV use was mainly based on the preserved or improved neurological status.

Cognitive performance in transient global hypoxic brain injury due to moderate drowning

INTRODUCTION

Drowning is a serious and frequently neglected public health threat. Primary respiratory impairment after submersion often leads to brain dysfunction. Depending on the period of global hypoxia (respiratory failure), clinical aspects of neurological dysfunction are evident on the first evaluation after the water rescue. Nowadays, many neuropsychological assessments after drowning are inconclusive, with some studies reporting only minor neurological or cognitive impairments. The aim of this study is to identify measures in neuropsychological tests that most contribute to classify volunteers as moderate drowning subjects or healthy controls. To the best of our knowledge, this study is the first neuropsychological prospective case-control study of moderate drowning in a country with large coastal cities.

METHOD

Fifteen moderate drowning patients (DP), who met the inclusion criteria, were compared with 18 healthy controls (HC). All subjects were assessed on memory, learning, visual spatial ability, executive function, attention, and general intellectual functioning and underwent structural magnetic resonance (MR) imaging of the brain at 3.0 T, in order to exclude subjects with anatomic abnormalities.

RESULTS

Neuropsychological tests assessing learning, execution function, and verbal fluency-Rey Auditory Verbal Learning Test (RAVLT) general learning ability, Digit Span total, Phonological Verbal Fluency (total FAS correct), and Brief Visuospatial Memory Test Revised (BVMT) correct recognition-have the strongest discriminating ability, using predictive models via the partial least squares (PLS) approach for data classification, while the other tests have shown similar predictive values between groups.

CONCLUSIONS

Learning, execution function, and verbal fluency domains were the most critically affected domains. Serious impairments in the same domains have already been reported in severe drowning cases, and we hypothesize that subtle alterations found in moderate drowning cases, although not sufficient to be detected in daily routine, may possibly have a negative impact on cognitive reserve.

Functional integrity in children with anoxic brain injury from drowning

Drowning is a leading cause of accidental injury and death in young children. Anoxic brain injury (ABI) is a common consequence of drowning and can cause severe neurological morbidity in survivors. Assessment of functional status and prognostication in drowning victims can be extremely challenging, both acutely and chronically. Structural neuroimaging modalities (CT and MRI) have been of limited clinical value. Here, we tested the utility of resting-state functional MRI (rs-fMRI) for assessing brain functional integrity in this population. Eleven children with chronic, spastic quadriplegia due to drowning-induced ABI were investigated. All were comatose immediately after the injury and gradually regained consciousness, but with varying ability to communicate their cognitive state. Eleven neurotypical children matched for age and gender formed the control group. Resting-state fMRI and co-registered T1-weighted anatomical MRI were acquired at night during drug-aided sleep. Network integrity was quantified by independent components analysis (ICA), at both group- and per-subject levels. Functional-status assessments based on in-home observations were provided by families and caregivers. Motor ICNs were grossly compromised in ABI patients both group-wise and individually, concordant with their prominent motor deficits. Striking preservations of perceptual and cognitive ICNs were observed, and the degree of network preservation correlated (ρ = 0.74) with the per-subject functional status assessments. Collectively, our findings indicate that rs-fMRI has promise for assessing brain functional integrity in ABI and, potentially, in other disorders. Furthermore, our observations suggest that the severe motor deficits observed in this population can mask relatively intact perceptual and cognitive capabilities. Hum Brain Mapp 38:4813-4831, 2017. © 2017 Wiley Periodicals, Inc.

2015 revised Utstein-style recommended guidelines for uniform reporting of data from drowning-related resuscitation: An ILCOR advisory statement

BACKGROUND

Utstein-style guidelines use an established consensus process, endorsed by the international resuscitation community, to facilitate and structure resuscitation research and publication. The first "Guidelines for Uniform Reporting of Data From Drowning" were published over a decade ago. During the intervening years, resuscitation science has advanced considerably, thus making revision of the guidelines timely. In particular, measurement of cardiopulmonary resuscitation elements and neurological outcomes reporting have advanced substantially. The purpose of this report is to provide updated guidelines for reporting data from studies of resuscitation from drowning.

METHODS

An international group with scientific expertise in the fields of drowning research, resuscitation research, emergency medical services, public health, and development of guidelines met in Potsdam, Germany, to determine the data that should be reported in scientific articles on the subject of resuscitation from drowning. At the Utstein-style meeting, participants discussed data elements in detail, defined the data, determined data priority, and decided how data should be reported, including scoring methods and category details.

RESULTS

The template for reporting data from drowning research was revised extensively, with new emphasis on measurement of quality of resuscitation, neurological outcomes, and deletion of data that have proved to be less relevant or difficult to capture.

CONCLUSIONS

The report describes the consensus process, rationale for selecting data elements to be reported, definitions and priority of data, and scoring methods. These guidelines are intended to improve the clarity of scientific communication and the comparability of scientific investigations.

2015 Revised Utstein-Style Recommended Guidelines for Uniform Reporting of Data From Drowning-Related Resuscitation: An ILCOR Advisory Statement

BACKGROUND

Utstein-style guidelines use an established consensus process, endorsed by the international resuscitation community, to facilitate and structure resuscitation research and publication. The first "Guidelines for Uniform Reporting of Data From Drowning" were published over a decade ago. During the intervening years, resuscitation science has advanced considerably, thus making revision of the guidelines timely. In particular, measurement of cardiopulmonary resuscitation elements and neurological outcomes reporting have advanced substantially. The purpose of this report is to provide updated guidelines for reporting data from studies of resuscitation from drowning.

METHODS

An international group with scientific expertise in the fields of drowning research, resuscitation research, emergency medical services, public health, and development of guidelines met in Potsdam, Germany, to determine the data that should be reported in scientific articles on the subject of resuscitation from drowning. At the Utstein-style meeting, participants discussed data elements in detail, defined the data, determined data priority, and decided how data should be reported, including scoring methods and category details.

RESULTS

The template for reporting data from drowning research was revised extensively, with new emphasis on measurement of quality of resuscitation, neurological outcomes, and deletion of data that have proved to be less relevant or difficult to capture.

CONCLUSIONS

The report describes the consensus process, rationale for selecting data elements to be reported, definitions and priority of data, and scoring methods. These guidelines are intended to improve the clarity of scientific communication and the comparability of scientific investigations.

Epidemiology and clinical analysis of critical patients with child maltreatment admitted to the intensive care units

Children with abuse who are admitted to the intensive care unit (ICU) may have high mortality and morbidity and commonly require critical care immediately. It is important to understand the epidemiology and clinical characteristics of these critical cases of child maltreatment.We retrospectively evaluated the data for 355 children with maltreatments admitted to the ICU between 2001 and 2015. Clinical factors were analyzed and compared between the abuse and the neglect groups, including age, gender, season of admission, identifying settings, injury severity score (ISS), etiologies, length of stay (LOS) in the ICU, clinical outcomes, and mortality. In addition, neurologic assessments were conducted with the Pediatric Cerebral Performance Category (PCPC) scale.The most common type of child maltreatments was neglect (n = 259), followed by physical abuse (n = 96). The mean age of the abuse group was less than that of the neglect group (P < .05). Infants accounted for the majority of the abuse group, and the most common etiology of abuse was injury of the central nervous system (CNS). In the neglect group, most were of the preschool age and the most common etiologies of abuse were injury of the CNS and musculoskeletal system (P < .001). The mortality rate in the ICU was 9.86%. The ISS was significantly associated with mortality in both the 2 groups (both P < .05), whereas the LOS in the ICU and injuries of the CNS, musculoskeletal system, and respiratory system were all associated with mortality in the neglect group (all P < .05). The PCPC scale showed poor prognosis in the abuse group as compared to the neglect group (P < .01).In the ICU, children in the abuse group had younger age, higher ISS, and worse neurologic outcome than those in the neglect group. The ISS was a predictor for mortality in the abuse and neglect groups but the LOS in the ICUs, injuries of the CNS, musculoskeletal system, and respiratory system were indicators for mortality in the neglect group. Most importantly, identifying the epidemiological information may provide further strategies to reduce the harm, lower the medical costs, and improve clinical care quality and outcomes in children with abuse.

White Matter Tract Pathology in Pediatric Anoxic Brain Injury from Drowning

BACKGROUND AND PURPOSE

Although drowning is a leading cause of mortality and morbidity in young children, the neuropathologic consequences have not been fully determined. The purpose of this article was to quantitatively characterize white matter microstructural abnormalities in pediatric anoxic brain injury from nonfatal drowning and investigate the correlation with motor function.

MATERIALS AND METHODS

Whole-brain T1-weighted and diffusion-weighted MR imaging datasets were acquired in 11 children with chronic anoxic brain injury and 11 age- and sex-matched neurotypical controls (4-12 years of age). A systematic evaluation form and scoring system were created to assess motor function. Tract-Based Spatial Statistics was used to quantify between-group alterations in the diffusion tensor imaging indices of fractional anisotropy and mean diffusivity and to correlate with per-subject functional motor scores.

RESULTS

Group-wise Tract-Based Spatial Statistics analyses demonstrated reduced fractional anisotropy in the bilateral posterior limbs of the internal capsule and the splenium of the corpus callosum (P < .001). Mean diffusivity was more diffusely increased, affecting the bilateral superior corona radiata, anterior and posterior limbs of the internal capsule, and external capsules (P < .001). Individual-subject fractional anisotropy and mean diffusivity values derived from the ROIs of the bilateral posterior limbs of the internal capsule strongly correlated with motor scores and demonstrated more potent between-group effects than with ROIs of the entire corticospinal tract.

CONCLUSIONS

These data particularly implicate the deep white matter, predominantly the posterior limbs of the internal capsule, as targets of damage in pediatric anoxic brain injury with drowning. The substantial involvement of motor-system tracts with relative sparing elsewhere is notable. These results localize white matter pathology and inform future diagnostic and prognostic markers.

Physiology Of Drowning: A Review

Drowning physiology relates to two different events: immersion (upper airway above water) and submersion (upper airway under water). Immersion involves integrated cardiorespiratory responses to skin and deep body temperature, including cold shock, physical incapacitation, and hypovolemia, as precursors of collapse and submersion. The physiology of submersion includes fear of drowning, diving response, autonomic conflict, upper airway reflexes, water aspiration and swallowing, emesis, and electrolyte disorders. Submersion outcome is determined by cardiac, pulmonary, and neurological injury. Knowledge of drowning physiology is scarce. Better understanding may identify methods to improve survival, particularly related to hot-water immersion, cold shock, cold-induced physical incapacitation, and fear of drowning.

Accidental hypothermia-an update : The content of this review is endorsed by the International Commission for Mountain Emergency Medicine (ICAR MEDCOM)

BACKGROUND

This paper provides an up-to-date review of the management and outcome of accidental hypothermia patients with and without cardiac arrest.

METHODS

The authors reviewed the relevant literature in their specialist field. Summaries were merged, discussed and approved to produce this narrative review.

RESULTS

The hospital use of minimally-invasive rewarming for non-arrested, otherwise healthy, patients with primary hypothermia and stable vital signs has the potential to substantially decrease morbidity and mortality for these patients. Extracorporeal life support (ECLS) has revolutionised the management of hypothermic cardiac arrest, with survival rates approaching 100 % in some cases. Hypothermic patients with risk factors for imminent cardiac arrest (temperature <28 °C, ventricular arrhythmia, systolic blood pressure <90 mmHg), and those who have already arrested, should be transferred directly to an ECLS-centre. Cardiac arrest patients should receive continuous cardiopulmonary resuscitation (CPR) during transfer. If prolonged transport is required or terrain is difficult, mechanical CPR can be helpful. Delayed or intermittent CPR may be appropriate in hypothermic arrest when continuous CPR is impossible. Modern post-resuscitation care should be implemented following hypothermic arrest. Structured protocols should be in place to optimise pre-hospital triage, transport and treatment as well as in-hospital management, including detailed criteria and protocols for the use of ECLS and post-resuscitation care.

CONCLUSIONS

Based on new evidence, additional clinical experience and clearer management guidelines and documentation, the treatment of accidental hypothermia has been refined. ECLS has substantially improved survival and is the treatment of choice in the patient with unstable circulation or cardiac arrest.

Cardiopulmonary Resuscitation Quality by Helicopter Rescue Swimmers While Flying

OBJECTIVE

Our objective was to assess the cardiopulmonary resuscitation (CPR) quality by helicopter rescue swimmers (HRSs) while flying.

METHODS

Twenty HRSs from the Spanish Maritime Safety took part in this study. The research protocol included 2 phases: a baseline test (5 minutes of CPR on land) and a challenge test (5 minutes of CPR on a Sikorsky S-61N helicopter in-flight). A Laerdal Resusci Anne mannequin with Laerdal PC Skill Reporting (Stavanger, Norway) was used to register CPR variables.

RESULTS

CPR quality on land versus in-flight was not significantly different. The mean chest compression (CC) depth (52.6 mm on land vs. 51.9 mm in-flight) was inside the recommended range, but mean CC rate (133 vs. 132 per minute), tidal volume (752 vs. 888 mL), and hands-off time (9 per cycle in both tests) were above the 2015 recommended goal. Incomplete chest re-expansion was observed in 19% of on land and 26% in-flight CCs. CPR quality was maintained throughout the 5-minute challenges.

CONCLUSION

HRSs are able to perform CPR in a flying helicopter with similar quality to CPR on land. They need additional training to avoid excessive CC rates, tidal volumes, and hands-off times and to permit chest re-expansion.

Targeted Temperature Management After Pediatric Cardiac Arrest Due To Drowning: Outcomes and Complications

OBJECTIVE

To describe outcomes and complications in the drowning subgroup from the Therapeutic Hypothermia After Pediatric Cardiac Arrest Out-of-Hospital trial.

DESIGN

Exploratory post hoc cohort analysis.

SETTING

Twenty-four PICUs.

PATIENTS

Pediatric drowning cases.

INTERVENTIONS

Therapeutic hypothermia versus therapeutic normothermia.

MEASUREMENTS AND MAIN RESULTS

An exploratory study of pediatric drowning from the Therapeutic Hypothermia After Pediatric Cardiac Arrest Out-of-Hospital trial was conducted. Comatose patients aged more than 2 days and less than 18 years were randomized up to 6 hours following return-of-circulation to hypothermia (n = 46) or normothermia (n = 28). Outcomes assessed included 12-month survival with a Vineland Adaptive Behavior Scale score of greater than or equal to 70, 1-year survival rate, change in Vineland Adaptive Behavior Scale-II score from prearrest to 12 months, and select safety measures. Seventy-four drowning cases were randomized. In patients with prearrest Vineland Adaptive Behavior Scale-II greater than or equal to 70 (n = 65), there was no difference in 12-month survival with Vineland Adaptive Behavior Scale-II score of greater than or equal to 70 between hypothermia and normothermia groups (29% vs 17%; relative risk, 1.74; 95% CI, 0.61-4.95; p = 0.27). Among all evaluable patients (n = 68), the Vineland Adaptive Behavior Scale-II score change from baseline to 12 months did not differ (p = 0.46), and 1-year survival was similar (49% hypothermia vs 42%, normothermia; relative risk, 1.16; 95% CI, 0.68-1.99; p = 0.58). Hypothermia was associated with a higher prevalence of positive bacterial culture (any blood, urine, or respiratory sample; 67% vs 43%; p = 0.04); however, the rate per 100 days at risk did not differ (11.1 vs 8.4; p = 0.46). Cumulative incidence of blood product use, serious arrhythmias, and 28-day mortality were not different. Among patients with cardiopulmonary resuscitation durations more than 30 minutes or epinephrine doses greater than 4, none had favorable Pediatric Cerebral Performance Category outcomes (≤ 3).

CONCLUSIONS

In comatose survivors of out-of-hospital pediatric cardiac arrest due to drowning, hypothermia did not result in a statistically significant benefit in survival with good functional outcome or mortality at 1 year, as compared with normothermia. High risk of culture-proven bacterial infection was observed in both groups.

Veterinary Forensic Pathology

Determining the cause of death in animals recovered from bodies of water, swimming pools, or other water-containing vessels is challenging. Animals recovered from water may or may not have drowned. The diagnosis of drowning is usually one of exclusion, requiring information from the crime scene, recovery scene, the medical history or reliable witness accounts. While there are characteristic macroscopic and microscopic lesions of drowning, none are specific and are dependent on the volume and tonicity of the drowning medium. Beyond interpreting the postmortem findings, the court may ask pathologists to comment on the behavioral and welfare implications of drowning. This requires an understanding of the drowning process, which is a complex series of sequential, concurrent, and overlapping cardiorespiratory reflexes, electrolyte and blood gas abnormalities, aspiration, physical exhaustion, and breathlessness eventually culminating in death. This review addresses the mechanisms, lesions, and diagnostic issues associated with drowning in nonaquatic companion animals.

Wilderness Medical Society Practice Guidelines for the Prevention and Treatment of Drowning

The Wilderness Medical Society convened a panel to review available evidence supporting practices for the prevention and acute management of drowning in out-of-hospital and emergency medical care settings. Literature about definition and terminology, epidemiology, rescue, resuscitation, acute clinical management, disposition, and drowning prevention was reviewed. The panel graded evidence supporting practices according to the American College of Chest Physicians criteria, then made recommendations based on that evidence. Recommendations were based on the panel's collective clinical experience and judgment when published evidence was lacking.

Lenticulostriate arterial distribution pathology may underlie pediatric anoxic brain injury in drowning

Drowning is a leading cause of neurological morbidity and mortality in young children. Anoxic brain injury (ABI) can result from nonfatal drowning and typically entails substantial neurological impairment. The neuropathology of drowning-induced pediatric ABI is not well established. Specifically, quantitative characterization of the spatial extent and tissue distribution of anoxic damage in pediatric nonfatal drowning has not previously been reported but could clarify the underlying pathophysiological processes and inform clinical management. To this end, we used voxel-based morphometric (VBM) analyses to quantify the extent and spatial distribution of consistent, between-subject alterations in gray and white matter volume. Whole-brain, high-resolution T1-weighted MRI datasets were acquired in 11 children with chronic ABI and 11 age- and gender-matched neurotypical controls (4–12 years). Group-wise VBM analyses demonstrated predominantly central subcortical pathology in the ABI group in both gray matter (bilateral basal ganglia nuclei) and white matter (bilateral external and posterior internal capsules) (P < 0.001); minimal damage was found outside of these deep subcortical regions. These highly spatially convergent gray and white matter findings reflect the vascular distribution of perforating lenticulostriate arteries, an end-arterial watershed zone, and suggest that vascular distribution may be a more important determinant of tissue loss than oxygen metabolic rate in pediatric ABI. Further, these results inform future directions for diagnostic and therapeutic modalities.

•

First quantitative characterization of anoxic brain injury in pediatric drowning

•

Voxel-based morphometry revealed predominant central subcortical pathology.

•

Lenticulostriate arterial distribution may underlie gray and white matter damage.

•

Predominant damage of motor-system components observed.

Reliability of the American Community Survey for unintentional drowning and submersion injury surveillance: a comprehensive assessment of 10 socioeconomic indicators derived from the 2006-2013 annual and multi-year data cycles

BACKGROUND

Our objective was to evaluate the reliability and predictability of ten socioeconomic indicators obtained from the 2006-2013 annual and multi-year ACS data cycles for unintentional drowning and submersion injury surveillance.

METHODS

Each indicator was evaluated using its margin of error and coefficient of variation. For the multi-year data cycles we calculated the frequency that estimates for the same geographic areas from consecutive surveys were statistically significantly different. Relative risk estimates of drowning-related deaths were constructed using the National Center for Health Statistics compressed mortality file. All analyses were derived using census counties.

RESULTS

Five of the ten socioeconomic indicators derived from the annual and multi-year data cycles produced high reliability CV estimates for at least 85 % of all US counties. On average, differences in socioeconomic characteristics for the same geographic areas for consecutive 3- and 5-year data cycles were unlikely to be caused by sampling error in only 17 % (5-89 %) and 21 % (5-93 %) of all counties. No indicator produced statistically significant relative risk estimates across all data cycles and survey years.

CONCLUSIONS

The reliability of the annual and multi-year county-level ACS data cycles varies by census indicator. More than 75 % of the differences in estimates between consecutive multi-year surveys are likely to have occurred as a result of sampling error, suggesting that researchers should be judicious when interpreting overlapping survey data as reflective of real changes in socioeconomic conditions. Although no indicator predicted disparities in drowning-related injury mortality across all data cycles and years, further studies are needed to determine if these associations remain consistent at different geographic scales and for injury morbidity.

Patterns of multiorgan dysfunction after pediatric drowning

AIMS

To evaluate patterns of multiorgan dysfunction and neurologic outcome in children with respiratory and cardiac arrest after drowning.

METHODS

Single center retrospective chart review of children aged 0-21 years admitted between January 2001 and January 2012 to the pediatric intensive care unit at Children's Hospital of Pittsburgh with a diagnosis of drowning/submersion/immersion. Organ dysfunction scores were calculated for first 24h of admission as defined by the Pediatric Logistic Organ Dysfunction Score-1 (PELOD-1) and Pediatric Multiple Organ Dysfunction Score (P-MODS). Neurologic outcome at hospital discharge was assigned Pediatric Cerebral and Overall Performance Category Scale scores.

RESULTS

We identified 60 cases of pediatric drowning in which 21 children experienced cardiorespiratory arrest (CA) and 39 had respiratory arrest (RA). All children with CA had multiorgan failure and 81% had a poor neurologic outcome at hospital discharge while 49% of children with RA had multiorgan failure and none had an unfavorable neurological outcome (p<0.001). The most common organ failures in both CA and RA groups within the first 24h of admission were respiratory, followed by neurologic, cardiovascular, gastrointestinal, hematological, and least commonly, renal.

CONCLUSION

Patterns of organ failure differ in children with CA and RA due to drowning. The contribution of multiorgan failure to poor outcome and evaluation of the impact of augmenting cerebral resuscitation with MOF-targeting therapies after drowning deserves to be explored.

Outcome after resuscitation beyond 30 minutes in drowned children with cardiac arrest and hypothermia: Dutch nationwide retrospective cohort study

OBJECTIVES

To evaluate the outcome of drowned children with cardiac arrest and hypothermia, and to determine distinct criteria for termination of cardiopulmonary resuscitation in drowned children with hypothermia and absence of spontaneous circulation.

DESIGN

Nationwide retrospective cohort study.

SETTING

Emergency departments and paediatric intensive care units of the eight university medical centres in the Netherlands.

PARTICIPANTS

Children aged up to 16 with cardiac arrest and hypothermia after drowning, who presented at emergency departments and/or were admitted to intensive care.

MAIN OUTCOME MEASURE

Survival and neurological outcome one year after the drowning incident. Poor outcome was defined as death or survival in a vegetative state or with severe neurological disability (paediatric cerebral performance category (PCPC) ≥ 4).

RESULTS

From 1993 to 2012, 160 children presented with cardiac arrest and hypothermia after drowning. In 98 (61%) of these children resuscitation was performed for more than 30 minutes (98/160, median duration 60 minutes), of whom 87 (89%) died (95% confidence interval 83% to 95%; 87/98). Eleven of the 98 children survived (11%, 5% to 17%), but all had a PCPC score ≥ 4. In the 62 (39%) children who did not require prolonged resuscitation, 17 (27%, 16% to 38%) survived with a PCPC score ≤ 3 after one year: 10 (6%) had a good neurological outcome (score 1), five (3%) had mild neurological disability (score 2), and two (1%) had moderate neurological disability (score 3). From the original 160 children, only 44 were alive at one year with any outcome.

CONCLUSIONS

Drowned children in whom return of spontaneous circulation is not achieved within 30 minutes of advanced life support have an extremely poor outcome. Good neurological outcome is more likely when spontaneous circulation returns within 30 minutes of advanced life support, especially when the drowning incident occurs in winter. These findings question the therapeutic value of resuscitation beyond 30 minutes in drowned children with cardiac arrest and hypothermia.

Neuronal networks and energy bursts in epilepsy

Epilepsy can be defined as the abnormal activities of neurons. The occurrence, propagation and termination of epileptic seizures rely on the networks of neuronal cells that are connected through both synaptic- and non-synaptic interactions. These complicated interactions contain the modified functions of normal neurons and glias as well as the mediation of excitatory and inhibitory mechanisms with feedback homeostasis. Numerous spread patterns are detected in disparate networks of ictal activities. The cortical-thalamic-cortical loop is present during a general spike wave seizure. The thalamic reticular nucleus (nRT) is the major inhibitory input traversing the region, and the dentate gyrus (DG) controls CA3 excitability. The imbalance between γ-aminobutyric acid (GABA)-ergic inhibition and glutamatergic excitation is the main disorder in epilepsy. Adjustable negative feedback that mediates both inhibitory and excitatory components affects neuronal networks through neurotransmission fluctuation, receptor and transmitter signaling, and through concomitant influences on ion concentrations and field effects. Within a limited dynamic range, neurons slowly adapt to input levels and have a high sensitivity to synaptic changes. The stability of the adapting network depends on the ratio of the adaptation rates of both the excitatory and inhibitory populations. Thus, therapeutic strategies with multiple effects on seizures are required for the treatment of epilepsy, and the therapeutic functions on networks are reviewed here. Based on the high-energy burst theory of epileptic activity, we propose a potential antiepileptic therapeutic strategy to transfer the high energy and extra electricity out of the foci.

Drowning in children: Utstein style reporting and outcome

BACKGROUND

We report the incidence and mortality of paediatric drowning incidents according to 'Utstein Style for Drowning' guidelines.

METHODS

Retrospective study including all the drowned children under 16 years of age who were hospitalised or died with or without attempted cardiopulmonary resuscitation (CPR) between 1997 and 2007 in the province of Uusimaa, Finland. Survival rates provided at hospital discharge and after 1-year follow-up period are reported.

RESULTS

A total of 58 drowned children were either admitted to the paediatric intensive care unit or died during the study period. The median (interquartile range) age was 5.9 (3.1, 7.8) years. The annual incidence of drowning was 1.9/100,000 and was highest, 2.8/100,000, in children aged between 1 and 4 years. The annual mortality rate was 0.9/100,000. Of all the 58 patients, 14 (24%) died at the scene, 22 (38.1%) before the hospital discharge, and 26 (45%) within the 1 year. The number of non-fatal drownings was 1.2-fold that of fatal drownings. The survival rate of the 26 patients for whom CPR was initiated by emergency medical service (EMS) personnel was 42% at hospital discharge, with the 1-year survival rate being 27%.

CONCLUSIONS

The incidence of drowning in children and the survival rate of those children in whom CPR was initiated by EMS personnel was in line with the previously reported. However, the overall mortality rate in drowned children was higher than estimated in previous studies.

Neurocognitive long term follow-up study on drowned children

AIM OF THE STUDY

Report cognitive and neurological outcome later in life of surviving drowned children who had received CPR either from bystanders or from emergency medical services (EMS) units.

METHODS

Forty children who had drowned and admitted to pediatric intensive care unit after successful CPR between 1985 and 2007, were eligible for the study. Of those 21 gave a consent for neurological and neuropsychological examinations. All data are expressed as median (interquartile range). Mann-Whitley U, Wilcoxon signed ranks and Chi square tests were used.

RESULTS

The median age of the 21 patients at drowning was 2.4 (1.8, 5.5) years and 12.5 (8.6, 19.4) years at the time of neurological and neuropsychological examination. The median interval between the drowning accident and examinations was 8.1 (5.4, 14.4) years. Twelve patients (57.1%) had either signs of minor (6/21) or major neurological dysfunction (6/21). Eight subjects (40.0%) had full-scale intelligence quotient (FIQ) of less than 80 (range 20-78). The median estimated submersion time of the subjects with normal FIQ was 3.5 (2.0, 7.5)min, which was significantly shorter than for those with FIQ<80, 12.5 (5.0, 22.5)min (p=0.0013). Cognitive or neurologic deficits were detected in 17 of the 21 subjects, although 11 of them were reported to have a full recovery at the hospital discharge.

CONCLUSIONS

This study showed that 57% of the drowned and resuscitated children had neurological dysfunction and 40% a low FIQ. Neurological and neuropsychological long term follow-up in drowned children is highly recommended.

Association of water temperature and submersion duration and drowning outcome

AIM

Evaluate the roles of water temperature and submersion duration in the outcome of drowning victims.

METHODS

Subjects were those who drowned in open water (lakes, rivers, and ocean) in three counties in Washington State between 1975 and 1996. We performed a case control study to assess the association between age, reported submersion duration, and estimated water temperature and drowning outcomes. Cases were victims with good outcomes (survival with normal or mild/moderate neurologic sequelae). Controls were victims with bad outcomes (death or severe neurologic sequelae or persistent vegetative state). We used Poisson regression to estimate odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

Of the total 1094 open water drowning victims, most were male (85%),white (84%), and with a mean age of 27 years. Most drownings occurred in lakes (51%) and in cold (≥6-16 °C (44%)) or very cold waters (<6 °C (34%)). Most (78%) had bad outcomes (74% died; 4% survived with severe neurologic sequelae. Of those with good outcomes, 88.2% were submerged <6 min, 7.4% 6-10 min and 4.3% for 11-60 min. Victims with good outcomes were 61% (95% CI 0.23-0.65) less likely to be submerged for 6 to 10 min and 98% (95% CI 0.01-0.04) less likely to be submerged for 11 or more minutes. Water temperature was not associated with outcome.

CONCLUSIONS

A protective effect of cold water for drowning victims was not found; estimated submersion duration was the most powerful predictor of outcome. Recommendations for initiation of rescue and resuscitation efforts should be revised to reflect the very low likelihood of good outcome following submersion greater than 10 min.

Out-of-hospital cardiac arrest due to drowning among children and adults from the Utstein Osaka Project

BACKGROUND

Children have better outcomes after out-of-hospital cardiac arrest (OHCA) than adults. However, little is known about the difference in outcomes between children and adults after OHCA due to drowning.

OBJECTIVES

The aim of this study is to assess the outcome after OHCA due to drowning between children and adults. Our hypothesis is that outcomes after OHCA due to drowning would be in better among children (<18 years old) compared with adults (≥18 years old).

METHOD

This prospective population-based, observational study included all emergency medical service-treated OHCA due to drowning in Osaka, Japan, between 1999 and 2010 (excluding 2004). Outcomes were evaluated between younger children (0-4 years old), older children (5-17 years old), and adults (≥18 years old). Major outcome measures were one-month survival and neurologically favorable one-month survival defined as cerebral performance category 1 or 2. Multivariate logistic regression analyses were used to account for potential confounders.

RESULTS

During the study period, 66,716 OHCAs were documented, and resuscitation was attempted for 62,048 patients (1300 children [2%] and 60,748 adults [98%]). Among these OHCAs, 1737 (3% of OHCAs) were due to drowning (36 younger children [2%], 32 older children [2%], and 1669 adults [96%]). The odds of one-month survival were significantly higher for younger children (28% [10/36]; adjusted odds ratio [AOR], 20.20 [95% confidence interval {CI} 7.45-54.78]) and older children (9% [3/32]; AOR, 4.47 [95% CI 1.04-19.27]) when compared with adults (2% [28/1669]). However, younger children (6% [2/36]; AOR, 5.23 [95% CI 0.52-51.73]) and older children (3% [1/32]; AOR, 2.53 [95% CI 0.19-34.07]) did not have a higher odds of neurologically favorable outcome than adults (1% [11/1669]).

CONCLUSION

In this large OHCA registry, children had better one-month survival rates after OHCA due to drowning compared with adults. Most survivors in all groups had unfavorable neurological outcomes.