Prognostic factors and outcome after drowning in an adult population

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.

Early application of non-invasive ventilation for children with pulmonary edema after drowning

BACKGROUND

The present study aimed to assess the efficacy of non-invasive ventilation (NIV) on the clinical course, oxygenation, need for invasive mechanical ventilation (IMV), and outcomes for children with pulmonary edema after drowning.

METHODS

We conducted a retrospective chart review. Children who were referred to the pediatric emergency department due to drowning-related pulmonary edema and underwent NIV between May 2014 and October 2020 were included. Demographics, vital signs, clinical findings, and results of laboratory and radiologic investigations were recorded. Patients were divided into six groups using the Szpilman classification system. The need for IMV, the need for pediatric intensive care unit admission, and the length of NIV treatment and stay in the pediatric intensive care unit were recorded for each patient.

RESULTS

Twenty-five patients were enrolled. According to the Szpilman classification, 13 (52.0%) patients were evaluated as grade 3 and 12 (48.0%) as grade 4. All patients were treated with bi-level positive airway pressure in the spontaneous / timed mode. A significant increase in oxygen saturation (SpO₂) and SpO₂/fraction of inspired oxygen ratios was observed from the beginning of NIV treatment and this increase was also observed for the second and fourth hours. There was a decrease in respiratory rate at the fourth hour of NIV treatment. No patient subsequently deteriorated to require IMV.

CONCLUSIONS

We have reported a favorable clinical course of drowning patients who underwent early use of NIV in the pediatric emergency department. Management of drowning patients with pulmonary edema by NIV with close follow-up can be successfully applied in selected cases.

2021 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Neonatal Life Support; Education, Implementation, and Teams; First Aid Task Forces; and the COVID-19 Working Group

The International Liaison Committee on Resuscitation initiated a continuous review of new, peer-reviewed published cardiopulmonary resuscitation science. This is the fifth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations; a more comprehensive review was done in 2020. This latest summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation task force science experts. Topics covered by systematic reviews in this summary include resuscitation topics of video-based dispatch systems; head-up cardiopulmonary resuscitation; early coronary angiography after return of spontaneous circulation; cardiopulmonary resuscitation in the prone patient; cord management at birth for preterm and term infants; devices for administering positive-pressure ventilation at birth; family presence during neonatal resuscitation; self-directed, digitally based basic life support education and training in adults and children; coronavirus disease 2019 infection risk to rescuers from patients in cardiac arrest; and first aid topics, including cooling with water for thermal burns, oral rehydration for exertional dehydration, pediatric tourniquet use, and methods of tick removal. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, according to the Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations or good practice statements. Insights into the deliberations of the task forces are provided in Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces listed priority knowledge gaps for further research.

2021 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

The International Liaison Committee on Resuscitation initiated a continuous review of new, peer-reviewed published cardiopulmonary resuscitation science. This is the fifth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations; a more comprehensive review was done in 2020. This latest summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation task force science experts. Topics covered by systematic reviews in this summary include resuscitation topics of video-based dispatch systems; head-up cardiopulmonary resuscitation; early coronary angiography after return of spontaneous circulation; cardiopulmonary resuscitation in the prone patient; cord management at birth for preterm and term infants; devices for administering positive-pressure ventilation at birth; family presence during neonatal resuscitation; self-directed, digitally based basic life support education and training in adults and children; coronavirus disease 2019 infection risk to rescuers from patients in cardiac arrest; and first aid topics, including cooling with water for thermal burns, oral rehydration for exertional dehydration, pediatric tourniquet use, and methods of tick removal. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, according to the Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations or good practice statements. Insights into the deliberations of the task forces are provided in Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces listed priority knowledge gaps for further research.

Treatment of the lung injury of drowning: a systematic review

Background

Drowning is a cause of significant global mortality. The mechanism of injury involves inhalation of water, lung injury and hypoxia. This systematic review addressed the following question: In drowning patients with lung injury, what is the evidence from primary studies regarding treatment strategies and subsequent patient outcomes?

Methods

The search strategy utilised PRISMA guidelines. Databases searched were MEDLINE, EMBASE, CINAHL, Web of Science and SCOPUS. There were no restrictions on publication date or age of participants. Quality of evidence was evaluated using GRADE methodology.

Results

Forty-one papers were included. The quality of evidence was very low. Seventeen papers addressed the lung injury of drowning in their research question and 24 had less specific research questions, however included relevant outcome data. There were 21 studies regarding extra-corporeal life support, 14 papers covering the theme of ventilation strategies, 14 addressed antibiotic use, seven papers addressed steroid use and five studies investigating diuretic use. There were no clinical trials. One retrospective comparison of therapeutic strategies was found. There was insufficient evidence to make recommendations as to best practice when supplemental oxygen alone is insufficient. Mechanical ventilation is associated with barotrauma in drowning patients, but the evidence predates the practice of lung protective ventilation. There was insufficient evidence to make recommendations regarding adjuvant therapies.

Conclusions

Treating the lung injury of drowning has a limited evidentiary basis. There is an urgent need for comparative studies of therapeutic strategies in drowning.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03687-2.

Resuscitation and emergency care in drowning: A scoping review

BACKGROUND

The ILCOR Basic Life Support Task Force and the international drowning research community considered it timely to undertake a scoping review of the literature to identify evidence relating to the initial resuscitation, hospital-based interventions and criteria for safe discharge related to drowning.

METHODS

Medline, PreMedline, Embase, Cochrane Reviews and Cochrane CENTRAL were searched from 2000 to June 2020 to identify relevant literature. Titles and abstracts and if necessary full text were reviewed in duplicate. Studies were eligible for inclusion if they reported on the population (adults and children who are submerged in water), interventions (resuscitation in water/boats, airway management, oxygen administration, AED use, bystander CPR, ventilation strategies, ECMO, protocols for hospital discharge (I), comparator (standard care) and outcomes (O) survival, survival with a favourable neurological outcome, CPR quality, physiological end-points).

RESULTS

The database search yielded 3242 references (Medline 1104, Pre-Medline 202, Embase 1722, Cochrane reviews 12, Cochrane CENTRAL 202). After removal of duplicates 2377 papers were left for screening titles and abstracts. In total 65 unique papers were included. The evidence identified was from predominantly high-income countries and lacked consistency in the populations, interventions and outcomes reported. Clinical studies were exclusively observational in nature.

CONCLUSION

This scoping review found that there is very limited evidence from observational studies to inform evidence based clinical practice guidelines for drowning. The review highlights an urgent need for high quality research in drowning.

The Use of Exogenous Lung Surfactant (Poractant Alfa) in Acute Respiratory Failure by Drowning

Drowning is an acute respiratory failure as a result from immersion or submersion of the airways in a liquid medium (predominantly water). Inhalation of water causes severe lung damage due to the destruction of pulmonary surfactant, resulting in decreased lung elasticity, alveolar collapse, alteration of ventilation-perfusion ratio, intrapulmonary blood shunting, hypoxia, acute lung injury, and Acute Respiratory Distress Syndrome (ARDS). Poractant alfa (Curosurf®), a natural surfactant effective in the treatment of newborn respiratory distress, has been used in various forms of ARDS, but in drowning syndromes, experience is still poor. We describe a series of nine clinical cases of drowning, six adults and three children, treated in our Intensive Care Unit (ICU) with endobronchial administration of poractant alfa. After 24 and 48 hours of administration in all cases, there was an improvement in arterial blood gas analysis (ABG) parameters and imaging. All patients were discharged without clinical consequences.

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.

Unmanned aerial vehicles (drones) to prevent drowning

BACKGROUND

Drowning literature have highlighted the submersion time as the most powerful predictor in assessing the prognosis. Reducing the time taken to provide a flotation device and prevent submersion appears of paramount importance. Unmanned aerial vehicles (UAVs) can provide the location of the swimmer and a flotation device.

OBJECTIVE

The objective of this simulation study was to evaluate the efficiency of a UAV in providing a flotation device in different sea conditions, and to compare the times taken by rescue operations with and without a UAV (standard vs UAV intervention). Several comparisons were made using professional lifeguards acting as simulated victims. A specifically-shaped UAV was used to allow us to drop an inflatable life buoy into the water.

RESULTS

During the summer of 2017, 28 tests were performed. UAV use was associated with a reduction of time it took to provide a flotation device to the simulated victim compared with standard rescue operations (p < 0.001 for all measurements) and the time was reduced even further in moderate (81 ± 39 vs 179 ± 78 s; p < 0.001) and rough sea conditions (99 ± 34 vs 198 ± 130 s; p < 0.001). The times taken for UAV to locate the simulated victim, identify them and drop the life buoy were not altered by the weather conditions.

CONCLUSION

UAV can deliver a flotation device to a swimmer safely and quickly. The addition of a UAV in rescue operations could improve the quality and speed of first aid while keeping lifeguards away from dangerous sea conditions.

Therapeutic Hypothermia for Asphyxial Out-of-Hospital Cardiac Arrest Due to Drowning: A Systematic Review of Case Series and Case Reports

The objective of this review was to summarize published evidence of the effectiveness of therapeutic hypothermia in patients with drowning-associated asphyxial out-of-hospital cardiac arrest (OHCA) and to explore any preliminary favorable factors in the management of therapeutic hypothermia to improve survival and neurological outcome. Drowning may result in asphyxial OHCA or hypothermic OHCA, but the former does not provide any potential neuroprotective effect as the latter may do. Electronic literature searches of Ovid Medline, Embase, Cochrane Library, and Scopus were performed for all years from inception to July 2016. Primary studies in the form of case reports, letters to the editor, and others with higher quality are included, but guidelines, reviews, editorials, textbook chapters, conference abstracts, and nonhuman studies are excluded. Non-English articles are excluded. Relevant studies are then deemed eligible if the drowning OHCA patient's initial temperature was above 28°C, which implies asphyxial cardiac arrest, and intentional therapeutic hypothermia was instituted. Because of the narrow scope of interest and strict definition of the condition, limited studies addressed it, and no randomized controlled trials (RCT) could be selected. Thirteen studies covering 35 patients are included. No quantitative synthesis, assessment of study quality, or assessment of bias was performed. It is conjectured that extended therapeutic hypothermia of 48-72 hours might help prevent reperfusion injury during the intermediate phase of postcardiac arrest care to benefit patients of drowning-associated asphyxial OHCA, but this finding only serves as preliminary observation for future research. No conclusive recommendation could be made regarding the duration of and the time of onset of therapeutic hypothermia. Future research should put effort on RCT, particularly the effect of extended duration of 48-72 hours. Important parameters should be reported in detail. Asphyxial and hypothermic OHCA should be differentiated.

Clinical features and prognostic factors in drowning children: a regional experience

Purpose

This study aimed to evaluate the clinical features of children who have survived a water submersion incident, and to identify risk factors for prognosis.

Methods

We retrospectively reviewed the medical records of patients who experienced submersion between January 2005 and December 2014. The patients were classified into 2 groups, according to complications, and prognostic factors were evaluated.

Results

During the study period, 29 children experienced submersion (20 boys and 9 girls; mean age, 83.8±46.4 months). Submersion occurred most commonly in the summer, with the peak incidence in August. The most frequent Szpilman clinical score was grade 5 (13 patients; 44.8%), followed by grade 6 (7 patients; 24.1%), and grades 1 or 2 (3 patients; 10.3%). Five children (17.2%) in the poor prognosis group died or had hypoxic ischemic encephalopathy, and the overall mortality rate was 6.9%. Poor prognosis after submersion was associated with lower consciousness levels (P=0.003), higher Szpilman scores (P=0.007), greater need for intubation and mechanical ventilator support (P=0.001), and longer duration of oxygen therapy (P=0.015). Poor prognosis was also associated with lower bicarbonate levels (P=0.038), as well as higher sodium, aspartate transaminase (AST), and alanine transaminase (ALT) levels (P=0.034, P=0.006, and P=0.005, respectively). Szpilman clinical scores were positively correlated with consciousness levels (r=0.489, P=0.002) and serum liver enzyme levels (AST and ALT; r=0.521, P=0.004).

Conclusion

We characterized the prognostic factors associated with submersion outcomes, using the Szpilman clinical score, which is comparable to consciousness level for predicting mortality.

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.

Drowning: an overlooked cause of out-of-hospital cardiac arrest in Canada

INTRODUCTION

Drowning is a major public health concern, yet little is known about the characteristics of drowning patients. The objectives of this study were to describe the demographic and clinical characteristics of out-of-hospital cardiac arrest (OHCA) attributed to drowning in Ontario and to compare the characteristics of OHCA attributed to drowning to those of presumed cardiac etiology.

METHODS

A retrospective, observational study was carried out of consecutive OHCA patients of drowning etiology in Ontario between August 2006 and July 2011. Bivariate analysis was used to evaluate differences between drowning and presumed cardiac etiologies.

RESULTS

A total of 31,763 OHCA patients were identified, and 132 (0.42%) were attributed to drowning. Emergency medical services treated 98 patients, whereas the remaining 34 met the criteria for legislative death. Overall, 5.1% of drowning patients survived to hospital discharge. When compared to patients of presumed cardiac etiology, drowning patients were younger and their arrest was more likely to be unwitnessed, present with a nonshockable initial rhythm, occur in a public location, and receive bystander cardiopulmonary resuscitation (CPR). A nonsignificant trend was noted for drowning cases to more frequently have a public access AED applied. There were no significant differences in the gender ratio or paramedic response times. Drowning patients were more likely to be transported to hospital but had a trend to be less likely to arrive with a return of spontaneous circulation. They were also more likely to be admitted to hospital but had no difference in survival to hospital discharge.

CONCLUSIONS

Significant differences exist between OHCA of drowning and presumed cardiac etiologies. Most drownings are unwitnessed, occur in public locations, and present with nonshockable initial rhythms, suggesting that treatment should focus on bystander CPR. Future initiatives should focus on strategies to improve supervision in targeted locations and greater emphasis on bystander-initiated CPR, both of which may reduce drowning mortality.

Extracorporeal membrane oxygenation in near-drowning patients with cardiac or pulmonary failure

Background

The aim of this study was to determine the early outcomes of using extracorporeal membrane oxygenation (ECMO) in near-drowning patients with cardiac or pulmonary failure.

Methods

This study was based on data from 9 patients including 2 children (mean age 33; 8 males, 1 female) who received ECMO after near-drowning between 2008 and 2013. Veno-arterial or veno-arteriovenous ECMO was used in 2 patients with sustained cardiac arrest and veno-venous ECMO was used in 7 patients with severe acute respiratory distress syndrome (ARDS). The means of the partial arterial oxygen pressure (PaO₂), Murray score, sequential organ failure assessment (SOFA) score, and simplified acute physiology score II (SAPS-II) prior to ECMO were 59.7 ± 9.9 mmHg on 100% oxygen, 3.5 ± 0.6, 11.4 ± 1.9, and 73.0 ± 9.2, respectively.

Results

The PaO₂ mean improved to 182 ± 152 mmHg within 2 h post-ECMO. The mean of SOFA score and SAPS-II decreased significantly to 8.6 ± 3.2 (p = 0.013) and 46.4 ± 5.1 (p = 0.008), respectively, at 24 h post-ECMO with mean flow rate of 3.9 ± 0.8 l/min. ECMO was weaned at a mean duration of 188 (range, 43–672) h in all patients. Seven patients were discharged home without neurological sequelae, while 2 patients who had hypoxic brain damage died after further referral. The overall survival with favourable neurological outcomes at 3 months was 77.8%. There were no complications related to ECMO.

Conclusions

ECMO was safe and effective for patients with ongoing cardiac arrest or ARDS after a near-drowning incident and can be used as a resuscitative strategy in near-drowning patients with cardiac or pulmonary failure resistant to conventional ventilator therapy.

Brain resuscitation in the drowning victim

Drowning is a leading cause of accidental death. Survivors may sustain severe neurologic morbidity. There is negligible research specific to brain injury in drowning making current clinical management non-specific to this disorder. This review represents an evidence-based consensus effort to provide recommendations for management and investigation of the drowning victim. Epidemiology, brain-oriented prehospital and intensive care, therapeutic hypothermia, neuroimaging/monitoring, biomarkers, and neuroresuscitative pharmacology are addressed. When cardiac arrest is present, chest compressions with rescue breathing are recommended due to the asphyxial insult. In the comatose patient with restoration of spontaneous circulation, hypoxemia and hyperoxemia should be avoided, hyperthermia treated, and induced hypothermia (32-34 °C) considered. Arterial hypotension/hypertension should be recognized and treated. Prevent hypoglycemia and treat hyperglycemia. Treat clinical seizures and consider treating non-convulsive status epilepticus. Serial neurologic examinations should be provided. Brain imaging and serial biomarker measurement may aid prognostication. Continuous electroencephalography and N20 somatosensory evoked potential monitoring may be considered. Serial biomarker measurement (e.g., neuron specific enolase) may aid prognostication. There is insufficient evidence to recommend use of any specific brain-oriented neuroresuscitative pharmacologic therapy other than that required to restore and maintain normal physiology. Following initial stabilization, victims should be transferred to centers with expertise in age-specific post-resuscitation neurocritical care. Care should be documented, reviewed, and quality improvement assessment performed. Preclinical research should focus on models of asphyxial cardiac arrest. Clinical research should focus on improved cardiopulmonary resuscitation, re-oxygenation/reperfusion strategies, therapeutic hypothermia, neuroprotection, neurorehabilitation, and consideration of drowning in advances made in treatment of other central nervous system disorders.

Therapeutic hypothermia in adult cardiac arrest because of drowning

BACKGROUND

Therapeutic hypothermia in adult victims who suffer cardiac arrest following drowning has been applied in only a small number of cases. In the last 4 years, we have employed therapeutic hypothermia to decrease hypoxia-induced brain injury in these patients. The purpose of the present study was to report the results of the treatment of these patients.

METHODS

This study investigated the utilisation of therapeutic hypothermia on consecutive patients with cardiac arrest because of drowning between 2005 and 2008. The study was conducted retrospectively, collecting data by reviewing medical records. Hypothermia, with a target temperature of 32-34°C, was induced for 24 h. Neurological outcomes were classified using the cerebral performance categories (CPCs). The primary outcome was neurological function at discharge.

RESULTS

Twenty patients were treated with therapeutic hypothermia. Four patients (20%) exhibited a favourable neurological outcome (CPC 1-2). Two patients (10%) remained in a vegetative state at discharge (CPC 4), and 14 patients (70%) died (CPC 5). The most common complications during therapeutic hypothermia were pancreatitis and rhabdomyolysis. A longer duration of advanced cardiac life support (P = 0.035), an absence of motor response to pain after 3 days (P = 0.003), an abnormal brain imaging (P = 0.005) and a lack of cortical response to somatosensory evoked potential (P = 0.008) were related to an unfavourable outcome (CPC 3-5).

CONCLUSION

The present study did not demonstrate an advantage of therapeutic hypothermia in adult cardiac arrest after drowning compared with previous studies treated with conventional therapy. Further prospective studies are needed to evaluate the effects of therapeutic hypothermia.

Evaluation of coma: a critical appraisal of popular scoring systems

Numerous scoring scales have been proposed and validated to evaluate coma for rapid pre-hospital assessment and triage, disease severity, and prognosis for morbidity and mortality. These scoring systems have been predicated on core features that serve as a basis for this review and include ease of use, inter-rater reliability, reproducibility, and predictive value. Here we review the benefits and limitations of the most popular coma scoring systems. The methods include search of Medline, databases, and manual review of article bibliographies. Few of the many available coma scales have gained widespread approval and popularity. The best known and widely accepted scale is the Glasgow Coma Scale (GCS). The Reaction Level Scale (RLS85) has utility and proven benefit, but little acceptance outside of Scandinavia. The newer Full Outline of UnResponsiveness (FOUR) score provides an attractive replacement for all patients with fluctuating levels of consciousness and is gradually gaining wide acceptance.

Induced hypothermia in comatose survivors of asphyxia: a case series of 14 consecutive cases

BACKGROUND

Induced hypothermia is widely used for comatose survivors of cardiac arrest. Other causes of hypoxic brain injury carry a poor prognosis when treated using traditional methods. At our hospital, hypothermia has also been used for the management of all comatose survivors of asphyxiation. The aim of the present study was to report the results of the management of these patients.

METHODS

Hospital charts of all patients admitted unconscious after asphyxiation during a 7-year period were reviewed. This included patients after hanging, drowning, carbon monoxide intoxication and other gas intoxications. In all patients, hypothermia with a target temperature of 32-34 degrees C was induced with external or intravascular cooling for 24 h. The primary outcome was neurologic function at discharge.

RESULTS

Fourteen male patients were treated with hypothermia, eight after hanging, three after drowning, two after carbon monoxide intoxication and one after methane intoxication. All were deeply comatose (Glasgow Coma Score 3-5) on arrival to hospital. Nine had been resuscitated from cardiac arrest. There were nine survivors (65%), all with good neurological recovery (Cerebral Performance Category 1-2). Four out of five non-survivors showed cerebral edema already on arrival computed tomographic (CT) scan while none of the nine survivors did.

CONCLUSIONS

The results of this study suggest that an early abnormal CT scan of the brain in patients resuscitated after asphyxiation carries an adverse prognosis. The favorable outcome of the patients in the present study suggests that a randomized clinical trial on the use of induced hypothermia in patients exposed to severe asphyxia might be warranted.