CPR Start Sequence for Drowning

Last Full Review: ILCOR 2022; American Red Cross Scientific Advisory Council 2021
Last Update: 2023

The pathophysiology of the drowning process is unique and is a continuum of events that include laryngospasm and possible resultant asphyxia. As a result of the constellation of events, severe hypoxemia ensues, which leads to cardiac arrest. This process contrasts with cardiac arrest from primary cardiac etiologies. A 2021 American Red Cross Scientific Advisory Council scientific review led to the Red Cross guidelines recommending a ventilations-first approach to starting cardiopulmonary resuscitation (CPR) (American Red Cross Scientific Advisory Council 2021b).

Evidence Summary

A systematic review by the American Red Cross Scientific Advisory Council in 2021 (American Red Cross Scientific Advisory Council 2021b) evaluated evidence for use of a ventilations-first approach to CPR in drowning victims with cardiac arrest, compared with a compressions-first CPR approach. Indirect evidence identified an association between ventilations with CPR in drowning victims and improved outcomes. One observational study reported a higher odds ratio for survival following cardiac arrest in drowning victims who received bystander ventilations compared with those who did not receive ventilations (Hubert et al. 2016, 924). A retrospective analysis of cardiac arrest registry data, including drowning victims, reported improved neurologically favorable survival in patients aged 5 to 15 years and improved survival to hospital discharge in all age groups who received compression-ventilation CPR (CV-CPR), compared with CPR without ventilations (Tobin et al. 2020, 141).

A 2022 systematic review and Consensus on Science with Treatment Recommendation (Wyckoff et al. 2022; Dunne et al. 2022) by the International Liaison Committee on Resuscitation (ILCOR) reviewed evidence for a compression-first resuscitation strategy in adults and children in cardiac arrest following drowning compared with a ventilation-first strategy. No studies were identified that were considered relevant to the question. The authors reviewed consensus statements and literature to help inform good practice statements. One study noted was a 2004 retrospective analysis of 46 nonbreathing drowning victims rescued by lifeguards, of which 19 (41.3%) received in-water immediate resuscitation with ventilations, and 27 (58.7%) received delayed resuscitation after being brought to shore (Szpilman and Soares 2004, 25). Survival was significantly higher in the group receiving in-water resuscitation with ventilations compared with the in-water resuscitation with no ventilations group (87.5% versus 25%, P<0.001). Survival with favorable functional outcome was also higher in the in-water resuscitation with ventilations group compared with the in-water resuscitation with no ventilations group (52.6% versus 7.4%).

A second study of pediatric drowning cases reported worse functional outcomes in children with cardiac arrest compared with respiratory arrest alone (81% versus 0%, P<0.001), suggesting that early intervention with ventilations before cardiac arrest may improve outcomes (Mtaweh et al. 2015, 91).

Insights and Implications

The studies included in the ILCOR systematic review are felt to provide additional indirect evidence supporting the 2021 American Red Cross Scientific Advisory Council systematic review and conclusions. The Red Cross guidelines recommending the use of a ventilations-first approach to CPR remain unchanged and reflect evidence suggesting that earlier ventilations may improve outcomes. For lay persons who are not trained or willing to provide CV-CPR, a compression-only CPR approach continues to be recommended by the Red Cross.

Compression-Only and Compression-Ventilation CPR for Drowning Process Resuscitation

Last Full Review: ILCOR 2023; American Red Cross Scientific Advisory Council 2021

Current Red Cross Basic Life Support guidelines for adults recommend the use of standard cardiopulmonary resuscitation (CPR) with ventilations by a trained lay responder, with a 30:2 compression-to-ventilation ratio. The use of compression-only CPR (CO-CPR) is an alternative to compression-ventilation CPR (CV-CPR) when a responder is unwilling or unable to provide ventilations. For healthcare professionals, CV-CPR is also recommended with a 30:2 compression-to-ventilation ratio in the absence of an advanced airway.

For children and infants, CPR with compressions and ventilations is recommended for both lay responders and healthcare professionals—with a compression-to-ventilation ratio of 30:2. When two healthcare professionals are present, a ratio of 15:2 should be used. Compression-only CPR may be used as an alternative to CPR with compressions and ventilations when someone is unwilling or unable to provide ventilations. However, the hypoxic mechanism of drowning has raised the question of whether CO-CPR is of benefit compared to no compressions for a cardiac arrest secondary to drowning.

Evidence Summary

A 2021 systematic review (American Red Cross Scientific Advisory Council: Resuscitation 2021b) by the American Red Cross Scientific Advisory Council evaluated the sequence of actions and the compression-to-ventilation ratio for cardiac arrest due to drowning. Four indirect observational studies were included in the review:

1. A 2018 retrospective study (Chan et al. 2018, 44) of drowning cases in swimming pools in Singapore treated by emergency medical services over a 2-year period found that of the 93 patients who received CPR, four were reported to regain consciousness with ventilations alone.
2. One observational study (Hubert et al. 2016, 924) prospectively analyzed all drowning cardiac arrest patients reported to the French Cardiac Arrest Registry. The patients who received bystander ventilations displayed a much higher rate of intact vital signs at hospital admission compared to those who did not. Additionally, they reported a statistically significant higher odds ratio for survival with bystander ventilations (OR, 6.742).
3. An observational cohort study (Fukuda et al. 2019, 166) analyzed all drowning cardiac arrest patients presenting to Japanese emergency departments over a 3-year span to evaluate the effect of bystander CPR using compressions and ventilations, compared with CO-CPR. No statistical difference was shown for the outcomes of favorable neurological status at hospital discharge at 30 days when comparing the conventional CPR group with the compression-only group. However, over 90% of the study population was over the age of 18, and over 80% of the population was age 65 and over.
4. Tobin et al. (Tobin et al. 2020, 141) used 4 years of data from the Cardiac Arrest Registry to Enhance Survival (CARES) database to retrospectively analyze 548 cases of cardiac arrest following drowning, when information was available about the type of bystander CPR performed. The study reported that between 2013 and 2017, patients in the conventional CPR with ventilations group (71/29.7%) had a greater odds of survival to hospital discharge compared with the CO-CPR group (59/24.7%) (aOR, 1.54; 95% CI, 1.01–36; P=0.046). However, there was no significant difference found for the outcome of neurologically favorable survival for the group of patients in the CV-CPR group (59/24.7%) compared with the patients (50/16.2%) in the CO-CPR group (aOR, 1.35; 95% CI, 0.86–2.10; P=0.19). A subgroup analysis of patients aged 5 years to 15 years showed conventional CV-CPR to be associated with greater odds of neurologically favorable survival (aOR, 2.68;95% CI, 1.10–6.77; P=0.03).

A 2023 systematic review (Bierens et al. 2023, 100406) and Consensus on Science with Treatment Recommendations (Sempsrott et al. 2022; Berg et al. 2023) by the International Liaison Committee on Resuscitation (ILCOR) looked for studies of adults and children in cardiac arrest following drowning who received CO-CPR compared with standard CO-CPR. This review included two studies evaluated in the American Red Cross Scientific Advisory Council review (Tobin et al. 2020, 141; Fukuda et al. 2019, 166). A good practice statement was made that CPR in drowned out-of-hospital cardiac arrest patients who have been removed from the water remains consistent with CPR for all patients in cardiac arrest. The statement includes a recommendation that bystanders perform chest compressions for all adults in cardiac arrest, and it is suggested that bystanders who are trained, able and willing to give rescue breaths and chest compressions do so for adults in cardiac arrest.

Treatment recommendations by ILCOR (Sempsrott et al. 2022; Berg et al. 2023) include a suggestion that bystanders provide CPR with ventilation for infants and children younger than 18 years of age with out-of-hospital cardiac arrest. If bystanders cannot provide rescue breaths as part of CPR for infants and children younger than 18 years with out-of-hospital cardiac arrest, it is recommended that they should at least provide chest compressions. The International Liaison Committee on Resuscitation specifically makes a good practice statement for healthcare professionals and those with a duty to respond to drowning (e.g., lifeguards) to provide ventilations in addition to chest compressions if they have been trained and are able and willing to do so.

Insights and Implications

Given the unique role of airway and respiratory pathophysiology in the drowning process, with cardiac arrest primarily the result of anoxia, ventilations should be a priority during treatment. Studies in the American Red Cross Scientific Advisory Council systematic review (American Red Cross Scientific Advisory Council: Resuscitation January 2021b) suggest an association between ventilations and improved outcomes. This includes an association between bystander ventilations without compressions and higher odds of survival, and a significant finding of increased neurologically favorable survival in patients aged 5 to 15 years who received CV-CPR compared with CO-CPR. The typical drowning victim is young, does not have underlying cardiac disease, and is often identified and rescued early in the drowning process, making them potentially at greater odds of survival through early ventilations and CPR with ventilations. The Red Cross supports the training of all lay responders in CPR with ventilations, while recommending the use of CO-CPR by untrained lay responders and others who are unwilling or unable to provide ventilations with CPR.

Ventilation With and Without Equipment for Drowning Process Resuscitation

Last Full Review: ILCOR 2023; American Red Cross Scientific Advisory Council 2017

Cardiac arrest during the drowning process is primarily the result of hypoxia, in contrast to adult cardiac arrest, which is primarily of cardiac origin. This has led to questions regarding the optimal approach to airway management and ventilations in resuscitation from the drowning process.

Evidence Summary

There are no studies of adults and children in cardiac arrest following drowning that directly compare providing ventilations using equipment (such as a bag-valve mask device, supraglottic airway or endotracheal tube) with providing ventilations without equipment. A systematic review by the International Liaison Committee on Resuscitation (ILCOR) (Bierens et al. 2023, 100406; Abelairas-Gómez et al. 2022; Berg et al. 2023) identified indirect evidence from a study (Ryan et al. 2021, 130) comparing outcomes following the use of a supraglottic (advanced) airway compared with the use of bag-mask ventilation. A lower odds of survival to hospital admission was reported following the use of a supraglottic airway compared with bag-mask ventilation (aOR, 0.40; 95% CI, 0.19–0.86). Worse outcomes were also identified in studies in children intubated by emergency medical services professionals compared with use of bag-mask ventilation (OR, 0.04; 95% CI, 0.01–0.20; (Joanknecht et al. 2015, 123) and OR, 0.25 (95% CI, 0.08–0.83), (Kieboom et al. 2015, h418) respectively. No evidence was identified to suggest a change from current recommendations for Basic Life Support (BLS) and Advanced Life Support guidance for lay persons or for BLS responders and healthcare professionals. The indirect evidence was considered by the ILCOR review authors in making a good practice statement that bag-mask ventilation can be used by lifeguards or other BLS responders with a duty to respond, on the condition that it is part of a competency-based training program with regular retraining and maintenance of equipment.

A good practice statement was also made by ILCOR recommending the use of mouth-to-mouth, mouth-to-nose or pocket-mask ventilations by BLS responders and lay responders for adults and children in cardiac arrest caused by drowning. Healthcare professionals should follow normal guidelines for airway management and ventilation of adults and children in cardiac arrest caused by drowning (Abelairas-Gómez et el. 2022; Berg 2023).

A 2017 American Red Cross Scientific Advisory Council scientific review updated in 2021 evaluated the use of ventilation with a bag-valve-mask device versus mouth-to-mask for a single rescuer or multiple rescuers caring for a nonbreathing person. The review included 14 studies comparing ventilation techniques. One randomized controlled trial (Adelborg et al. 2011, 618) included 60 lifeguards and found that mouth-to-mask ventilation was the most effective technique, in that they provided the most effective ventilation and had the least interruptions during chest compressions.

A study (Paal et al. 2008, 42) evaluating retention of ventilation skills using mouth-to-mouth, mouth-to-mask and mouth-to-face shield reported skill retention to be highest at 1 year for mouth-to-mask, while ventilation using a bag-valve-mask device had the highest risk of hyperinflation. All studies included in this review were performed using manikins and the certainty of evidence was low to very low. The review concluded that ventilation by mouth-to-pocket mask is the best technique to teach lay providers to ventilate nonbreathing patients. Ventilation using a bag-valve-mask device appears more difficult to learn and retain.

Insights and Implications

The hypoxic mechanism of cardiac arrest in drowning supports recommendations for the use of cardiopulmonary resuscitation with ventilations or rescue breaths. For bystanders and lay responders, this can be accomplished with mouth-to-mouth, mouth-to-nose or pocket-mask ventilation. Lifeguards and those with a duty to respond are frequently trained in the technique of bag-mask-ventilation. Because it is difficult to obtain a good mask seal while ventilating with a bag-valve-mask device, the Red Cross recommends only using this technique when there are multiple rescuers, with one person controlling the mask seal while another delivers ventilations using the bag. In most cases, a single rescuer will find mouth-to-mask ventilations easier and more effective than bag-mask-ventilation.

Automated External Defibrillator Use in Drowning Resuscitation

Last Full Review: ILCOR 2023

Out-of-hospital cardiac arrest with a shockable rhythm (ventricular fibrillation/ventricular tachycardia) attributed to drowning has been reported in only 2% to 14% of patients (Wyckoff et al. 2022, e645; Bierens et al. 2021, 205). Although concerns have been expressed over the use of an automated external defibrillator (AED) on a person in cardiac arrest in an aquatic environment, the use of AEDs in simulation studies appears feasible and safe (Olasveengen et al. 2020, S41; Olasveengen et al. 2017, e424). The use of AEDs is recommended by the Red Cross after beginning cardiopulmonary resuscitation (CPR) and once available, where feasible and safe. Should an AED be used before CPR in cardiac arrest following drowning or should CPR be provided before using an AED?

Evidence Summary

A 2022 International Liaison Committee on Resuscitation (ILCOR) systematic review and Consensus on Science with Treatment Recommendations (Berg et al. 2023; Beerman et al. 2022) of AED use first versus CPR first in cardiac arrest following drowning did not identify any studies that addressed the question. Previous reviews have identified simulation studies showing that AED use for cardiac arrest following drowning appears feasible (Wyckoff et al. 2021, 229; Wyckoff et al. 2022, e645; de Vries et al. 2006, 247).

Related literature was reviewed and discussed by the review authors (Berg et al. 2023; Beerman et al. 2022). While cardiac arrest following drowning is most commonly the result of the hypoxic drowning process, it may be secondary to a primary cardiac event in adults and children (Beerman et al. 2022). Shockable rhythms are rare in cardiac arrest following drowning but are slightly higher in children and witnessed events. However, there is conflicting data if outcomes are improved when shockable rhythms are present. One study (Dyson et al. 2013, 1114) discussed a review of 336 drowning-related, out-of-hospital cardiac arrests. The study reported that 6% were found to be in a shockable rhythm; for nonshockable rhythms, 79% were found to be in asystole and 13% with pulseless electrical activity. Improved outcomes were found to be associated with an initial shockable rhythm, with higher adjusted odds of survival to hospital discharge (aOR 48.70; 95% CI, 3.80–624.86).

The ILCOR systematic review authors weighed the potential benefits versus risks and disadvantages of adding the use of an AED to CPR following drowning. A good practice statement by ILCOR recommends that when available, an AED should be used in cardiac arrest following drowning in adults and children. Cardiopulmonary resuscitation should be started first and continued until an AED has been obtained and is ready for use for adults and children in cardiac arrest caused by drowning (Berg et al. 2023; Beerman et al. 2022).

Insights and Implications

While cardiac arrest following drowning is most commonly the result of hypoxia and the drowning process, it may also be the result of a primary cardiac event in both adults and children. The ILCOR good practice statement is consistent with the Red Cross guidelines for the use of an AED for cardiac arrest and supports a CPR-first approach to resuscitation from drowning. Concerns for safety related to the use of an AED in the aquatic environment have not been substantiated in the 2022 ILCOR review, however AED use should not be attempted while the drowning person is in water, and the chest should be dried off prior to use.

Prehospital Oxygen Following Drowning

 Last Full Review: ILCOR 2023

There are no studies on supplemental oxygen use by lifeguards or trained responders in drowning process resuscitation. However, the pathophysiology of the drowning process, including decreased oxygen diffusion capacities of the lungs following aspiration of water, provides a rationale for the administration of oxygen, when available, to persons with respiratory symptomatology following a drowning event. Should oxygen be provided following a drowning event?

Evidence Summary

A 2023 systematic review (Bierens et al. 2023, 100406) and Consensus on Science with Treatment Recommendations (Berg et al. 2023; Seesink et al. 2022) by the International Liaison Committee on Resuscitation (ILCOR) sought literature to answer the following question as it pertains to adults and children in cardiac arrest following drowning: Does oxygen administration before hospital arrival compared with no oxygen administration before hospital arrival change survival outcomes or return of spontaneous circulation (ROSC)? No direct evidence was identified that addressed the question.

A good practice statement was made that, when available, ILCOR recommends trained providers use the highest possible inspired oxygen concentration during prehospital resuscitation for adults and children in cardiac arrest following drowning. In making this statement, the authors noted that hypoxemia is associated with worse outcomes; that prompt initiation of bystander cardiopulmonary resuscitation (CPR) is associated with better outcomes in drowning; and that use of supplemental oxygen, when available during and after CPR, is an accepted practice in drowning resuscitation and other circumstances. However, there is evidence that prolonged administration of high-concentration oxygen may be harmful and there are no adult human studies comparing maximal inspired oxygen with another inspired oxygen concentration in CPR (Berg et al. 2023; Seesink et al. 2022). It was also noted that adding oxygen to resuscitation algorithms could increase their complexity, and it is recommended that oxygen use be limited to providers who are trained and practiced in its use during resuscitation.

There is uncertainty about the effectiveness of oxygen in the early stages after drowning, and the high-cost–low-benefit balance does not favor the use of pulse oximetry during resuscitation. Finally, it was noted that following ROSC, recommendations should be followed for oxygen titration (Berg et al. 2023; Seesink et al. 2022).

Insights and Implications

The new ILCOR systematic review, while not identifying direct evidence, describes the rationale behind their good practice statement and has been used to inform the Red Cross guidelines. The Red Cross guidelines reflect that responders who use oxygen must receive training in oxygen administration. When trained lifeguards and responders administer oxygen to adults or children without cardiac arrest but with respiratory distress or failure following a drowning event, oxygen should be titrated once pulse oximetry is available and a reliable reading can be obtained.

Special Considerations in Drowning Process Resuscitation

Most drownings of young children take place in a home pool where rescue can be rapid, and resuscitation can be started immediately after removal from the pool. In older children and adults, drowning may take place in a lake, river, or ocean, creating potential delays in starting cardiopulmonary resuscitation (CPR) or raising concern for use of an automated external defibrillator (AED) when close to the water and with wet skin. Is there evidence to support in-water resuscitation of a drowning victim? Does the wet environment or wet skin pose a hazard to use of an AED in a drowning victim?

Evidence Summary

In-Water Resuscitation

Last Full Review: ILCOR 2023; American Red Cross Scientific Advisory Council 2019

The topic of in-water resuscitation was most recently evaluated systematically by American Red Cross Scientific Advisory Council (American Red Cross Scientific Advisory Council: Aquatics. 2019) in 2019. Scoping reviews by International Liaison Committee on Resuscitation (ILCOR) in 2021 sought to identify literature related to in-water resuscitation, (Wyckoff et al. 2022, 229; Wyckoff et al. 2022, e645; Bierens et al. 2021b) and use of an AED in drowning (Wyckoff et al. 2022, 229; Wyckoff et al. 2022, e645; Bierens et al. 2021a). No evidence was identified to change the American Red Cross Scientific Advisory Council guidelines.

The American Red Cross Scientific Advisory Council scientific review (American Red Cross Scientific Advisory Council: Aquatics 2019) of in-water resuscitation focused on the technical feasibility and clinical outcomes. A single observational study was included (Szpilman and Soares 2004, 25) with 19 patients who received in-water resuscitation. Compared with the group of patients who did not receive in-water resuscitation, patients who received in-water resuscitation had significantly lower prehospital and hospital mortality. Other in-water resuscitation-specific studies used manikins in simulated rescue scenarios, (Lungwitz et al. 2015, 379; Barcala-Furelos et al. 2016, 480; Abelairas-Gómez et al. 2017, 176; International Life Saving Federation 2018) finding that:

• In-water resuscitation is feasible by mouth-to-mouth, bag-mask ventilation and laryngeal tube ventilation.
• In-water resuscitation increases the time and perceived difficulty of a rescue.
• In-water resuscitation increases the amount of measured water aspiration on the part of the patient.
• Lifeguards perform in-water resuscitation more effectively and efficiently than laypersons.

The American Red Cross Scientific Advisory Council review (American Red Cross Scientific Advisory Council: Aquatics. 2019) concluded that although the evidence is limited, in-water resuscitation is feasible but difficult, and can be physically and metabolically taxing to a rescuer, particularly if the rescuer is not properly trained and physically fit. Physical and metabolic demands and rescue time can be decreased with the use of rescue equipment. The 2021 scoping review (Nichol et al. 2015, 2203; Wyckoff et al. 2021; Bierens et al. 2021b) of in-water resuscitation by ILCOR concluded that in suitable water conditions, in-water resuscitation by highly trained rescue teams with water rescue equipment seems feasible.

AED Use for Drowning

Last Full Review: ILCOR 2023

A 2021 scoping review by ILCOR (Wyckoff et al. 2022, 229; Wyckoff et al. 2022, e645; Bierens et al. 2021a) sought to identify literature evaluating the use of an AED for adults and children following submersion in water, compared with no AED use. Only indirect evidence was found from observational studies. Of note, among 14,920 patients in 12 studies, out-of-hospital cardiac arrest with a shockable rhythm (ventricular fibrillation/ventricular tachycardia) attributed to drowning was reported in only 2% to 14% of patients. One study (Claesson et al. 2014, 644) with 529 patients was described as showing, with multivariable analysis, an association between a shockable rhythm and increased 30-day survival (Wyckoff et al. 2022, 229; Wyckoff et al. 2022, e645; Bierens et al. 2021a). Simulation studies included in this review were described as showing that AED use for cardiac arrest following drowning appears feasible and safe.

Insights and Implications

Because airway and respiratory pathophysiology, including systemic hypoxemia, are the most significant insults and primary cause of morbidity and mortality in the drowning process, the earlier an intervention can be applied to reverse the insult and the drowning process, the greater the chances should be for survival. The limited evidence suggests that in-water resuscitation is feasible, is performed better with proper training and equipment, and the use of rescue equipment may decrease the physical demands.

The review of AED uses for drowning confirms prior observations that the incidence of a shockable rhythm in cardiac arrest following drowning is lower than for cardiac arrest due to a primary cardiac etiology. Additional studies are needed to help identify which patients may be more likely to have a shockable rhythm following a submersion event and ways to increase the success of defibrillation while minimizing any risk of AED use in settings near water.

Resuscitation on a Boat Following Drowning

 Last Full Review: ILCOR 2023

Rescue boats are used by many lifeguard and rescue organizations to respond to drowning events in open water. Some rescue boats have trained crews, protocols and equipment to begin on-board resuscitation from the drowning process. After retrieving an unresponsive person from the water and onto a rescue boat, should the patient be transported to dry land immediately and thus delay resuscitation, or should resuscitation be initiated onboard and during transportation?

Evidence Summary

There are no human studies evaluating immediate resuscitation onboard a boat compared with delaying resuscitation until resuscitation can be performed on dry land. A systematic review by the International Liaison Committee on Resuscitation (ILCOR) (Bierens et al. 2023, 100406; Wyckoff et al. 2022, 229; Barcala-Furelos et al. 2022; Berg et al. 2023) provided a good practice statement suggesting that on-boat cardiopulmonary resuscitation (CPR) may be provided if rescuers trained in this technique determine that it is feasible and safe to attempt resuscitation. If rescuers feel that the application of immediate CPR is or becomes too difficult or unsafe, then the rescuers may delay resuscitation until on dry land. Previous scoping reviews by ILCOR (Wyckoff et al. 2022, e645; Wyckoff et al. 2022, 229; Bierens et al. 2023, 100406) have identified manikin studies and case series of resuscitation on a boat. The manikin studies evaluated CPR performance by lifeguards and fishermen on inflatable rescue boats or traditional fishing boats and found that while feasible, higher boat speed or sea conditions negatively impact the quality of resuscitation and make CPR physically demanding.

A case series with a total of 37 patients who received CPR by lifeboat crew reported survival at 1 month in three (8.1%) cases (Seesink et al. 2022, 53). Studies evaluating the use of an automated external defibrillator (AED) on a rescue boat show that their use is feasible (de Vries et al. 2006, 247). Automated external defibrillators are used in 5% to 32% of drowning events before arrival of emergency medical services (EMS), and a shockable rhythm is present in only 2% to 14% of drowning events (Wyckoff et al. 2022, e483; Wyckoff et al. 2022, 229). In the case series by Seesink et al. (Seesink et al. 2022, 53), an AED was connected in just over half of the resuscitations (19/37, 51.3%), including 12 (32.4%) on a lifeboat. None of the 12 patients survived, although this may partly reflect the time from the initial call to the connection of the AED. Reasons for not using an AED onboard included circumstances such as weather, challenging sea conditions or proximity to shore that led to a decision to proceed immediately to dry land and waiting ambulance crews (Seesink et al. 2022, 53).

Insights and Implications

The rationale for immediate resuscitation of a drowning person on a boat, or in water with ventilations only, is the rapid reversal of hypoxia and the hypoxic nature of cardiac arrest in the drowning process. Manikin studies suggest that resuscitation onboard a boat is feasible if conditions are safe and the number of available crew and deck space permit. However, high-quality CPR may be difficult to provide and rescuer fatigue may easily occur. Other factors to be considered by organizations that provide on-board resuscitation include the size, speed and stability of the rescue boat, the deck surface and size, weather, including sea or water conditions, boat operator skill, rescuer skills training and level of physical fitness, and distance from the boat to dry land and emergency medical services assistance.