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.

2023 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

The International Liaison Committee on Resuscitation engages in a continuous review of new, peer-reviewed, published cardiopulmonary resuscitation and first aid science. Draft Consensus on Science With Treatment Recommendations are posted online throughout the year, and this annual summary provides more concise versions of the final Consensus on Science With Treatment Recommendations from all task forces for the year. Topics addressed by systematic reviews this year include resuscitation of cardiac arrest from drowning, extracorporeal cardiopulmonary resuscitation for adults and children, calcium during cardiac arrest, double sequential defibrillation, neuroprognostication after cardiac arrest for adults and children, maintaining normal temperature after preterm birth, heart rate monitoring methods for diagnostics in neonates, detection of exhaled carbon dioxide in neonates, family presence during resuscitation of adults, and a stepwise approach to resuscitation skills training. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, using Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces list priority knowledge gaps for further research. Additional topics are addressed with scoping reviews and evidence updates.

2023 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

The International Liaison Committee on Resuscitation engages in a continuous review of new, peer-reviewed, published cardiopulmonary resuscitation and first aid science. Draft Consensus on Science With Treatment Recommendations are posted online throughout the year, and this annual summary provides more concise versions of the final Consensus on Science With Treatment Recommendations from all task forces for the year. Topics addressed by systematic reviews this year include resuscitation of cardiac arrest from drowning, extracorporeal cardiopulmonary resuscitation for adults and children, calcium during cardiac arrest, double sequential defibrillation, neuroprognostication after cardiac arrest for adults and children, maintaining normal temperature after preterm birth, heart rate monitoring methods for diagnostics in neonates, detection of exhaled carbon dioxide in neonates, family presence during resuscitation of adults, and a stepwise approach to resuscitation skills training. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, using Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces list priority knowledge gaps for further research. Additional topics are addressed with scoping reviews and evidence updates.

A systematic review of interventions for resuscitation following drowning

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 experience of drowning

Internationally, drowning is a leading cause of accidental death that features in many legal cases. In these cases, possible mitigations and the 'pain and suffering' in terms of the duration and subjective experience of drowning are often pivotal in determining levels of compensation and outcome. As a result, there is a requirement to understand the stages of the drowning process, and the duration and physiological and subjective responses associated with each stage. In this short review we focus on these issues.

Airway obstruction time and outcomes in patients with foreign body airway obstruction: multicenter observational choking investigation

Aim

Foreign body airway obstruction (FBAO) is a major public health concern worldwide for infants and older adults. This study determines the association between airway obstruction time and neurological outcomes to plan an effective response for patients with FBAO.

Methods

This multicenter retrospective observational study was carried out among patients with life‐threatening FBAO in Japan over a period of 4 years. The duration of airway obstruction was calculated from the time of the accident to the time of foreign body removal. The study examined the relationship between airway obstruction time and outcome. The primary outcome was vegetative state or death at hospital discharge.

Results

Among 119 patients, 68 were in the category of vegetative state or death. Logistic regression analysis showed that longer airway obstruction time (adjusted odds ratio 1.04; 95% confidence interval 1.01–1.07) was associated with vegetative state or death. When the cut‐off value was set at 10, the sensitivity was 0.88, the specificity 0.47, with the area under the curve 0.69. Using the other cut‐off value of 4 min, the negative predictive value was 1.00.

Conclusion

Longer airway obstruction time was associated with vegetative state or death for patients with FBAO. The incidence of vegetative state or death increased when the airway obstruction time exceeded 10 min. Meanwhile, 4 min or less may be set as a target time for foreign body removal in order to prevent vegetative state or death and plan an effective response.

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.

International Commission for Mountain Emergency Medicine Consensus Guidelines for On-Site Management and Transport of Patients in Canyoning Incidents

Canyoning is a recreational activity that has increased in popularity in the last decade in Europe and North America, resulting in up to 40% of the total search and rescue costs in some geographic locations. The International Commission for Mountain Emergency Medicine convened an expert panel to develop recommendations for on-site management and transport of patients in canyoning incidents. The goal of the current review is to provide guidance to healthcare providers and canyoning rescue professionals about best practices for rescue and medical treatment through the evaluation of the existing best evidence, focusing on the unique combination of remoteness, water exposure, limited on-site patient management options, and technically challenging terrain. Recommendations are graded on the basis of quality of supporting evidence according to the classification scheme of the American College of Chest Physicians.

Sports related to drowning

Aquatic sports are included in the top list of risky practices as the environment per se carries a possibility of death by drowning if not rescued in time. Not only are aquatic sports related to a high risk of death, but also all sports practiced on the water, over the water and on ice. Whatever the reason a person is in the water, drowning carries a higher possibility of death if the individual is unable to cope with the water situation, which may simply be caused by an inability to stay afloat and get out of the water or by an injury or disease that may lead to physical inability or unconsciousness. The competitive nature of sports is a common pathway that leads the sports person to exceed their ability to cope with the environment or simply misjudge their physical capability. Drowning involves some principles and medical interventions that are rarely found in other medical situations as it occurs in a deceptively hostile environment that may not seem dangerous. Therefore, it is essential that health professionals are aware of the complete sequence of action in drowning. This article focuses on the pulmonary injury in sports and recreational activities where drowning plays the major role.

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.

Current Concepts in the Pathophysiology and Management of Near-Drowning

Approximately 6,500 people drown in the United States each year. Nearly 50,000 of the estimated 500,000 annual near-drowning victims seek medical attention. Near-drowning is most common among children, young adults, blacks, males, and in the southern states. Risk factors for near-drowning include ethanol use, drugs, seizures, boating accidents, water sports, inadequate supervision of children, and voluntary hyperventilation. Alcohol use alone is associated with 37 to 47% of these cases. Although anoxia and hypothermia produce the major pathological changes associated with the morbidity of near-drowning, hypothermia may paradoxically exert a protective effect in some cases and is associated with most of the spectacular long term survivals. There is almost no difference in the clinical presentation of freshwater and saltwater near-drowning. Both situations often involve hypothermia, anoxic injury due to cardiac arrest, and the frequent progression to the adult respiratory distress syndrome. Basic principles of management include the immediate institution of cardiopulmonary resuscitation; aggressive rewarming, preferably with cardiopulmonary bypass; continuation of cardiopulmonary resuscitation at least until the patient has been effectively rewarmed; and appropriate supportive care if the patient develops the adult respiratory distress syndrome. Cerebral salvage techniques have not been proved to be beneficial in these patients.

The introduction of expired air resuscitation into Surf Life Saving Australia

Surf Life Saving Australia, which began in the early 1900s, initially adopted the indirect resuscitation methods used by the Royal Life Saving Society. As new indirect methods became available, both organisations adapted their resuscitation techniques and followed international developments closely. In the 1950s, accumulating evidence suggested that direct methods of resuscitation, such as mouth-to-mouth ventilation, might be more efficacious. Subsequently a number of investigations were carried out in Sydney at the Royal Prince Alfred Hospital on anaesthetised and paralysed patients. These experiments were recorded for an ABC documentary and reported at the International Convention on Life Saving Techniques held in Sydney in March 1960. Following the convention, Queensland Surf Life Saving conducted training sessions in cooperation with anaesthetists Roger Bennett and Tess Brophy (later Cramond), at St Andrew's Hospital in Brisbane. Two volunteers were anaesthetised and paralysed on two separate weekends to allow over one hundred people to gain experience in expired-air and bag-mask ventilation. One of the volunteers in these training exercises kindly provided much of the material that led to this paper, providing a first hand account of the experiments and an invaluable insight into the cooperation between anaesthetists and volunteer rescue associations.

Vomiting is not associated with poor outcomes in pediatric victims of unintentional submersions

INTRODUCTION

The outcome of submersion victims depends on submersion duration and the availability of timely and effective resuscitation. The prognostic implication of vomiting during resuscitation of submersion victims is unclear. The study sought to determine whether vomiting during resuscitation in children treated for unintentional submersion injuries adversely impacts outcome.

METHODS

This was a retrospective study of unintentional submersion victims under age 18 treated at an urban tertiary-care children's hospital from 2003-2009. Submersion and victim details were obtained from hospital, EMS, and fatality records. Outcomes studied were survival at 24 hours and condition (Favorable: good/mild impairment or Poor: death/severe disability) at hospital discharge. Descriptive comparisons between emesis groups (yes/no) and categorical covariates were analyzed.

RESULTS

There were 281 victims. The median age was 3 years; 66% were males. Most incidents occurred at swimming pools (77%) and bathtubs (16%). Most were hospitalized (83%). The presence or absence of emesis was documented in 246 (88%). Victims with emesis were significantly less likely to have apnea or be intubated in the ED, have a low ED GCS or die. No patient who had emesis died at 24 hours or had a poor outcome at hospital discharge. Victims who had emesis post-resuscitation were significantly more likely to have received CPR or chest compressions than rescue breaths.

CONCLUSIONS

Emesis in pediatric submersion victims is inversely associated with death at 24 hours or poor outcome at hospital discharge. The relationship between emesis and the adequacy of resuscitation of pediatric submersion victims needs to be further studied.

Helicopter-based in-water resuscitation with chest compressions: a pilot study

BACKGROUND

Drowning is a relevant worldwide cause of severe disability and death. The delay of ventilations and chest compressions is a crucial problem in drowning victims. Hence, a novel helicopter-based ALS rescue concept with in-water ventilation and chest compressions was evaluated.

METHODS

Cardio pulmonary resuscitation (CPR) and vascular access were performed in a self-inflating Heliboat platform in an indoor wave pool using the Fastrach intubating laryngeal mask, the Oxylator resuscitator, Lund University Cardiopulmonary Assist System (LUCAS) chest compression device and EZ-IO intraosseous power drill. The time requirement and physical exertion on a Visual Analogue Scale (VAS) were compared between a procedure without waves and with moderate swell.

RESULTS

Measurement of the elapsed time of the various stages of the procedure did not reveal significant differences between calm water and swell: Ventilation was initiated after 02:48 versus 03:02 and chest compression after 04:20 versus 04:18 min; the intraosseous cannulisation was completed after 05:59 versus 06:30 min after a simulated jump off the helicopter. The attachment of the LUCAS to the mannequin and the intraosseous cannulisation was rated significantly more demanding on the VAS during swell conditions.

CONCLUSIONS

CPR appears to be possible when performed in a rescue platform with special equipment. The novel helicopter-based strategy appears to enable the rescuers to initiate CPR in an appropriate length of time and with an acceptable amount of physical exertion for the divers. The time for the helicopter to reach the patient will have to be very short to minimise neurological damage in the drowning victim.

Surf lifeguard rescues

OBJECTIVE

This study assessed the utility of lifeguard rescue data for providing information on person and situation factors to inform surf bather drowning prevention research.

METHODS

The dataset comprised 872 beach-days (daily lifeguard reports) obtained from 26 beaches over a 95-day period in Victoria, Australia.

RESULTS

The rescue rate was 128 per 100,000 in-water bathers. One or more rescues were required on 125 beach-days (14%). Rescue on a beach-day was more likely for offshore wind conditions, relatively high daily air temperatures, and high bather numbers (P < .05). Compared to female bathers, males were more frequently rescued (65%) and more likely (P < .05) to be from a younger age group (30 years or less), although being older was associated with a relatively poorer condition on rescue.

CONCLUSIONS

Although rescues are proportional to water exposure, frequencies are also influenced by situation and person factors. Bathers at relatively high risk of rescue are hypothesized to be overrepresented in amenable sea and weather conditions, and poor patient condition on rescue may be associated with exposure to a preexisting health condition.

Resuscitation in a multiple casualty event

A major weakness in the emergency medical response to multiple casualty events continues to be the resuscitation component, which should consist of the systematic application of basic, advanced, and prolonged life support and definitive care within 24 hours. There have been major advances in emergency medical care over the last decade, including the feasibility of point-of-care ultrasound to aid in rapid assessment of injuries in the field, damage control resuscitation, and resuscitative surgery protocols, delivered by small trauma/resuscitation teams equipped with regional anesthesia capability for rapid deployment. Widespread adoption of these best practices may improve the delivery of resuscitative care in future multiple casualty events.

Diagnosis and management of environmental thoracic emergencies

Physiologic sequelae from increasing ambient pressure in underwater activities, decreasing ambient pressure while at altitude, or the consequences of drowning present a unique set of challenges to emergency physicians. In addition, several environmental toxins cause significant respiratory morbidity, whether they be pulmonary irritants, simple asphyxiants, or systemic toxins. It is important for emergency physicians to understand the pathophysiology of these illnesses as well as to apply this knowledge to the clinical arena either in the prehospital setting or in the emergency department. Current treatment paradigms and controversies within these regimens are discussed.

Recommendations for water safety and drowning prevention for travelers

Drowning is a serious worldwide, mostly preventable injury problem, particularly among international travelers. In 2000, approximately 449,000 people have drowned worldwide, and the exact number of travelers is not precisely known. Although comprehensive infectious disease information has been available to international travelers for many years, advice on injury risk and prevention, more specifically on drowning prevention, has received little attention. The goals of this review were to develop research-based drowning prevention and water-safety recommendations for travelers and to identify research needs for future recommendations. A group of injury-prevention and travel-medicine experts conducted several rounds of voting and ranking of the strength and evidence of drowning-prevention recommendations. Each of the thirty-two recommendations created have also been categorized using the Committee to Advise on Tropical Medicine and Travel scale and have been framed in the context of preevent, event, and postevent categories commonly used in injury-control theory and Haddon's Matrix. These recommendations were developed for use by travel-medicine professionals or others who prepare individuals for travel. Several of the identified interventions to prevent drownings lack conclusive scientific evidence of their effectiveness and warrant further studies to better understand their true effectiveness. Furthermore, funding for the studies of intervention effectiveness and the implications of these interventions for international travelers are essential, yet insufficient.

In-water resuscitation: a pilot evaluation

INTRODUCTION

The first and most important treatment for the apnoeic drowning victim is the rapid alleviation of hypoxia by artificial ventilation. Recent studies have suggested that commencing resuscitative efforts with the victim still in the water may be beneficial. The aim of this pilot study was to evaluate the feasibility and efficacy of in-water unsupported rescue breathing.

METHODS

Three lifeguards were taught how to perform in-water unsupported rescue breathing. Ventilation volume, inflation duration were recorded from a modified Laerdal resuscitation manikin. The rescue duration was recorded and compared to a rescue undertaken without in-water resuscitation.

RESULTS

The three lifeguards performed between seven and nine ventilations during each simulated rescue. This gave average inflation volumes for each lifeguard of 711 ml (S.D. 166), 750 ml (S.D. 108), 629 ml (S.D. 182) and average inflation duration of 0.8s (S.D. 0.3), 0.9s (S.D. 0.2) and 0.6s (S.D. 0.1). The rescue duration was increased from an average time of 1 min 10 s to 1 min 24 s by performing in-water resuscitation.

CONCLUSION

This study has demonstrated the feasibility and potential efficacy of in-water unsupported rescue breathing with a victim in deep water. Furthermore, the technique was not associated with an undue prolongation of the rescue duration over a 50 m rescue. In circumstances where the trained lifeguard finds themselves with an apnoeic victim in the water, with no buoyant rescue aid available, they may consider the application of in-water, unsupported rescue breathing, especially if recovery to dry land is likely to be delayed. The effectiveness of this technique, however, remains to be proven in the open water environment.

Drowning: a review of epidemiology, pathophysiology, treatment and prevention

Although often preventable, drowning remains a leading cause of accidental death, especially in children. New definitions classify drowning as the process of experiencing respiratory impairment from submersion or immersion in a liquid. The key pathophysiological feature in drowning is hypoxia. Accurate neurological prognosis cannot be predicted from the initial clinical presentation, laboratory, radiological, or electrophysiological examinations. Prompt and aggressive resuscitation attempts are crucial for optimal survival. This article reviews the epidemiology, pathophysiology, treatment, and prevention of drowning.

In-water resuscitation—is it worthwhile?

OBJECTIVES

At present, there is no reliable information indicating the best option of rescuing a non-breathing drowning victim in the water. Our objectives were to compare the outcomes of performing immediate in-water resuscitation (IWR) or delaying resuscitation until the victim is brought to shore.

MATERIAL AND METHODS

A retrospective data analysis was conducted of non-breathing drowning victims rescued by lifeguards in the coastal area of Rio de Janeiro, Brazil. Patients were coded as IWR and no-IWR (NIWR) cases based on the lifeguard's decision whether to perform IWR. Death and development of severe neurological damage (SND) were considered poor outcome.

RESULTS

Forty-six patients were studied. Their median age was 17 (9-31) years. Nineteen (41.3%) patients received IWR and 27 (58.7%) did not. The mortality rate was lower for IWR cases (15.8% versus 85.2%, P < 0.001). However, among surviving IWR cases, 6 (31.6%) developed SND. In multivariate analysis, higher age [odds ratio (OR) = 1.12 (95% confidence interval (CI) = 1.01-1.24), P = 0.038] was associated with death, while IWR [ OR = 0.05 (95% CI = 0.01-0.50), P = 0.011] was protective. When death or the development of SND was set as the dependent variable, longer cardiopulmonary arrest (CPA) duration was the unique variable selected (OR = 1.77 (95% CI = 1.13-2.79), P = 0.013]. Every patient with CPA duration higher than 14 min had a poor outcome.

CONCLUSIONS

Delaying resuscitation efforts were associated with a worse outcome for non-breathing drowning victims. In the cases studied, IWR was associated with improvement of the likelihood of survival. An algorithm was developed for its indications and to avoid unnecessary risks to both victim and rescuer.

Prevention of drowning in infants, children, and adolescents

Drowning is a leading cause of injury-related death in children. In 2000, more than 1400 US children younger than 20 years drowned. Most (91%) of these deaths were unintentional and were not related to boating. For each drowning death, it is estimated that at least 1 to 4 children suffer a serious nonfatal submersion event, many of which leave children with permanent disabilities. Environmental strategies, such as installation of 4-sided fences around swimming pools, and behavioral strategies, such as increased supervision of children while around water, are needed to prevent these tragedies.

Towards new models of cardiopulmonary resuscitation teaching: the role of practical scenario training on surf lifesavers' perceptions of resuscitation efficacy

INTRODUCTION

Surf lifesavers in Australia undertake numerous resuscitation scenarios in the course of their training and examination. The standard teaching and examination strategy is for the scenario to end with return of spontaneous circulation (ROSC) and then breathing. This study was performed to assess the effect of this training technique on lifesavers' expectation of successful resuscitation and to determine the effect of experience on these expectations.

METHODS

Participants were lifesavers from Surf Life Saving Sydney Northern Beaches (SLSSNB). Data was collected by questionnaire. Questionnaires were applied to newly qualified lifesavers, a random sample of patrolling lifesavers and a strategic group of lifesavers with extensive experience in resuscitation. Anticipation of ROSC was recorded on a visual analogue scale (VAS).

RESULTS

The mean VAS for the expected likelihood of successful resuscitation was 55.0+/-19.2% (95% CI: 51.3-58.6%). Published rates of ROSC range from 9 to 36.4%. Nearly 80% of our respondents expected better than 36.4% chance of ROSC. There was no difference in anticipation of ROSC between the three groups (F=0.41; 2,99df; P=0.67). Time since learning cardiopulmonary resuscitation (CPR) did not affect the expectancy of ROSC (F=0.92; 5,101df; P=0.47). Similarly, the number of resuscitations performed by an individual did not affect anticipation of successful outcome (F=0.13; 3,102df; P=0.94).

CONCLUSIONS

Surf lifesavers in the Sydney Northern Beaches branch have an exaggerated expectation of the chances of successful CPR following cardiac arrest. This expectation did not change with time since learning CPR or participation in actual resuscitations. New models for CPR education need to be investigated.

Drowning. Rescue, resuscitation, and reanimation

Several myths about drowning have developed over the years. This article has attempted to dispel some of these myths, as follows: 1. Drowning victims are unable to call or wave for help. 2. "Dry drownings" probably do not exist; if there is no water in the lungs at autopsy, the victim probably was not alive when he or she entered the water. 3. Do not use furosemide to treat the pulmonary edema of drowning; victims may need volume. 4. Seawater drowning does not cause hypovolemia, and freshwater drowning does not cause hypervolemia, hemolysis, or hyperkalemia. 5. Drowning victims swallow much more water than they inhale, resulting in a high risk for vomiting spontaneously or on resuscitation. No discussion of drowning would be complete without mentioning the importance of prevention. Proper pool fencing and water safety training at a young age are instrumental in reducing the risk for drowning. Not leaving an infant or young child unattended in or near water can prevent many of these deaths, especially bathtub drownings. Also crucial is the use of personal flotation devices whenever boating. Proper training in water safety is crucial for participation in water recreation and sporting activities, including SCUBA diving. The incidence of pediatric drowning deaths in the United States has decreased steadily over the past decade, perhaps as a result of increased awareness and attention to drowning-prevention measures (Box 1).

Health and safety problems and lack of information among international visitors backpacking through North Queensland

BACKGROUND

International visitors to tropical Australia may be exposed to health and safety problems. Because they are younger, stay longer and participate in more activities, backpackers have a greater exposure to such problems than other visitors.

METHOD

The study's aim was to determine how many backpackers experience problems and lack health and safety information. Four hundred and thirty-one international visitors staying in a random sample of youth hostels and backpacker accommodation in Townsville were surveyed over the summer.

RESULTS

Sixty two percent experienced a health and safety problem, commonly, insect bites, sunburn, headaches, lacerations, coral cuts, ear infections and diarrhea. Seventeen percent resolved only with professional help. Only 54% of backpackers had been offered health and safety information prior to departure, mainly vaccination advice.

CONCLUSION

The proportion of backpackers offered health and safety information about tropical Australia, and the breadth of that information, needs to be increased.

Near-drowning and drowning classification: a proposal to stratify mortality based on the analysis of 1,831 cases

STUDY OBJECTIVE

To establish an updated classification for near-drowning and drowning (ND/D) according to severity, based on mortality rate of the subgroups.

MATERIALS AND METHODS

We reviewed 41,279 cases of predominantly sea water rescues from the coastal area of Rio de Janeiro City, Brazil, from 1972 to 1991. Of this total, 2,304 cases (5.5%) were referred to the Near-Drowning Recuperation Center, and this group was used as the study database. At the accident site, the following clinical parameters were recorded: presence of breathing, arterial pulse, pulmonary auscultation, and arterial BP. Cases lacking records of clinical parameters were not studied. The ND/D were classified in six subgroups: grade 1--normal pulmonary auscultation with coughing; grade 2--abnormal pulmonary auscultation with rales in some pulmonary fields; grade 3--pulmonary auscultation of acute pulmonary edema without arterial hypotension; grade 4--pulmonary auscultation of acute pulmonary edema with arterial hypotension; grade 5--isolated respiratory arrest; and grade 6--cardiopulmonary arrest.

RESULTS

From 2,304 cases in the database, 1,831 cases presented all clinical parameters recorded and were selected for classification. From these 1,831 cases, 1,189 (65%) were classified as grade 1 (mortality=0%); 338 (18.4%) as grade 2 (mortality=0.6%); 58 (3.2%) as grade 3 (mortality=5.2%); 36 (2%) as grade 4 (mortality=19.4%); 25 (1.4%) as grade 5 (mortality=44%); and 185 (10%) as grade 6 (mortality=93%) (p<0.000001).

CONCLUSION

The study revealed that it is possible to establish six subgroups based on mortality rate by applying clinical criteria obtained from first-aid observations. These subgroups constitute the basis of a new classification.

Success of surf lifesaving resuscitations in Queensland, 1973-1992

OBJECTIVE

To determine the success of resuscitations performed by Queensland surf lifesavers and the factors associated with successful resuscitation.

DESIGN

Retrospective case survey, using data from Surf Life Saving Association of Australia resuscitation report forms.

SETTING

54 Queensland beaches patrolled by surf lifesavers, and nearby areas, between 1973 and 1992.

OUTCOME MEASURES

Reasons and success rates for resuscitation, distance from surf clubhouse, whether inside patrolled area, victim's age, sex, facial colour on presentation, occurrence of vomiting, airway difficulties and involvement of alcohol.

RESULTS

171 resuscitations were reported (80% involving males and 20% females), with a success rate of 67%. Seventy-two per cent were performed during patrol hours, 17% within patrolled areas (95% successful) and 55% outside patrolled areas (only 62% successful) (P = 0.004 for difference in success rates); resuscitation success rates fell with increasing distance from the surf clubhouse (P = 0.009). Reasons for resuscitation were: immersion, 70% (success rate, 68%); collapse, 22% (success rate, 47%); and surf or beach injury, 7% and 1%, respectively (success rate, 100% for each). Resuscitation was more likely to be successful if the victim's facial colour on presentation was normal, pale or blue, but not if grey, and if the victim did not vomit or regurgitate.

CONCLUSIONS

Resuscitation by surf lifesavers was highly successful when the victim was close to the surf patrol, indicating a need for funding to expand patrol areas. Public awareness of the greater safety of "bathing between the flags" (in the delineated patrol area) should be increased.

The use of the Heimlich maneuver in near drowning: Institute of Medicine report

The application of the Heimlich maneuver as the initial and perhaps only step for opening the airway in all near-drowning victims has been proposed by Henry Heimlich and Edward Patrick, contrary to current resuscitation guidelines for the treatment of near-drowning victims established by the Emergency Cardiac Care (ECC) Committee of the American Heart Association. Although the Heimlich maneuver is useful for the removal of aspirated solid foreign bodies, there is no evidence that death from drowning is frequently caused by aspiration of a solid foreign body that is not effectively treated by the current ECC recommendations. Furthermore, the evidence is insufficient to support the proposition that the Heimlich maneuver is useful for the removal of aspirated liquid. Moreover, because there is no evidence to support Heimlich's hypothesis that substantial amounts of water are aspirated by near-drowning victims or that such aspirated liquid causes brain damage and death, the available evidence does not support routine use of the Heimlich maneuver in the care of near-drowning victims. The routine use of the Heimlich maneuver for treatment of near drowning raises several concerns: (a) the amount of time it would take to repeat this maneuver and how long this would delay the initiation of artificial ventilation; (b) possible complications of the Heimlich maneuver, especially if the near drowning is associated with a cervical fracture; and (c) the prospect of teaching rescue workers a different protocol than that which is taught at present for resuscitating victims of cardiopulmonary arrest from all causes other than near drowning.(ABSTRACT TRUNCATED AT 250 WORDS)

Why some people do not drown. Hypothermia versus the diving response

OBJECTIVE

To examine our present state of knowledge regarding the remarkable survival of some victims from prolonged submersion for an hour or more. Debate continues on the relative importance of the two explanatory theories--diving response and hypothermia.

DATA SOURCES

A wide range of physiological, pathophysiological and clinical papers relating to the diving response, hypothermia and near-drowning, with emphasis on the period 1981-1991.

DATA SYNTHESIS

The normothermic human brain suffers irreversible damage if subjected to acute asphyxia for longer than 10 minutes. Significant resistance of brain tissue to hypoxia occurs only after its temperature has fallen from 37 degrees C to 30 degrees C or less. Body surface cooling depresses core temperature by only one-third of this drop in 10 minutes. Hence an additional factor, other than hypothermia, is required to explain survival from near-drowning. The idea that ingestion and aspiration of large amounts of cold water produce such a temperature drop lacks quantitative evidence. The diving response seen in marine mammals also occurs in humans but to a lesser extent; however, about 15% of volunteers tested exhibit a profound response. This response which starts immediately upon submersion prevents aspiration of water, redistributes oxygen stores to heart and brain, slows cardiac oxygen use and initiates a hypometabolic state. The possible influence of alcohol on these processes is considered.

CONCLUSIONS

Survival from prolonged near-drowning appears to depend upon a specific temporal interplay between the diving response and hypothermia, resulting in a protective state of hypometabolism.