Conflict of Interest Declaration
The ILCOR Continuous Evidence Evaluation process is guided by a rigorous ILCOR Conflict of Interest policy.
The following Task Force members and other authors were recused from the discussion as they declared a conflict of interest: none applicable.
The following Task Force members and other authors declared an intellectual conflict of interest and this was acknowledged and managed by the Task Force Chairs and Conflict of Interest committees: none applicable.
CoSTR Citation
Abelairas-Gómez C, Tobin JM, Jayashree M Bierens J, Olasveengen T, Bray J, Morley PT, Perkins GD. on behalf of the International Liaison Committee on Resuscitation BLS Life Support Task Force(s).
Ventilation strategies (with vs without equipment) following drowning Consensus on Science with Treatment Recommendations [Internet] Brussels, Belgium: International Liaison Committee on Resuscitation (ILCOR) Basic Life Support Task Force, October 24th 2022. Available from: http://ilcor.org.
Methodological Preamble
In 2019, the ILCOR Advanced Life Support (ALS) Task Force suggested using Bag Valve Mask (BVM) or an advanced airway strategy during adult CPR in any setting (weak recommendation, low to moderate certainty of evidence). When advanced airway management is used, the use of supraglottic airway devices (SGA) in a setting with a low tracheal intubation (TI) success rate is recommended (weak recommendation, low certainty of evidence). In the case of children, BMV rather than tracheal intubation (TI) or (SGA) in a pre-hospital setting is recommended (weak recommendation, very low certainty of evidence) [Soar 2019 e826]. Due to a lack of new evidence, the ALS COSTR 2020 did not propose any change in the recommendations regarding airway management during CPR [Berg 2020 S92]. In addition, the selection of a particular airway management technique over another likely depends on the skills and training of the rescuer as well as specific patient circumstances [Soar 2019 e826]. While adult cardiac arrest arises primarily from cardiac causes, drowning is caused primarily by hypoxia. This difference may suggest consideration of a different strategy regarding airway management in drowning.
This review was initiated following a request from the ILCOR BLS Task Force as part of a series of reviews relating to drowning.
The continuous evidence evaluation process for this Consensus on Science with Treatment Recommendations (CoSTR) started with a scoping review of the literature [Bierens 2021 205]. Following completion of the scoping review the decision was taken to progress to a systematic review. The systematic review was registered with PROSPERO CRD42021259983. The PICO question was developed by a group of drowning experts and approved by the ILCOR BLS Task Force. The search strategy was developed and run by Samantha Johnson. The results of the search strategy were reviewed and development of this CoSTR was conducted by Cristian Abelairas-Gómez, Joshua M Tobin and Muralidharan Jayashree in collaboration with Joost Bierens and Gavin Perkins. The CoSTR was reviewed and agreed by Basic Life Support and Paediatric Task Forces.
PICOST
Population |
Adults and children in cardiac arrest1 following drowning2 |
Intervention |
Ventilation with equipment before hospital arrival |
Comparison |
Ventilation without equipment before hospital arrival |
Outcomes |
Critical 9: Survival to discharge / 30 days or later Critical 8: Survival with favourable neurological outcome to discharge / 30 days or later Critical 7: Return of spontaneous circulation (ROSC) |
Study Design |
Randomized controlled trials (RCTs) and non-randomized studies (non-randomized controlled trials, interrupted time series, controlled before-and-after studies, cohort studies) are eligible for inclusion. Unpublished studies (e.g., conference abstracts, trial protocols), manikin studies, narrative reviews and animal studies were excluded. All years and all languages are included as long as there is an English abstract |
Timeframe |
Database inception to current time. |
1A broad definition of cardiac arrest will be used including those who are unconscious and not breathing normally or those requiring resuscitation interventions e.g. chest compressions, defibrillation.
2 Drowning is the process of experiencing respiratory impairment from submersion/immersion in liquid
PROSPERO Registration CRD4202125998
Consensus on Science
A search of Medline, Pre-Medline, Embase, Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Trials on 26th September 2021 identified 2266 references. After de-duplication, 1849 titles and abstracts were reviewed. Full text review was conducted for 21 papers. No studies were identified which addressed the PICOST question.
Seven indirect observational studies discussed data regarding airway management of drowned patients with cardiac arrest [Garner 2015 93; Hubert 2016 928; Joanknecht 2015 123; Kieboom 2015 h418; Reynolds 2019 129; Salas Ballestín 2021 e192; Ryan 2021 130], of which only one compared outcomes in function of the ventilation equipment used [Ryan 2021 130]. In this study, the use of SGA was associated with lower odds ratio (OR) than TI (OR=0.56, 95%CI: 0.42-0.76) and BVM (OR=0.40, 95%CI: 0.19-0.86) regarding survival to hospital admission and survival to hospital discharge respectively. Although the use of SGA is recommended for adults with out-of-hospital cardiac arrest in settings with a low TI success rate (weak recommendation, low certainty of evidence) [Berg 2020 S92; Soar 2019 e826], a case-series argued that SGA might be unsuitable for drowned patients due to the low lung compliance and high airway resistance [Baker 2011 675]. In most studies, TI was a signal of the overall morbidity of the patient, which might explain that two studies showed worse outcomes when victims were intubated ((OR=0.04, 95%CI: 0.01-0.20) [Joanknecht 2015 123]; OR=0.25,95%CI: 0.08-0.83) [Kieboom 2015 h418]). Nevertheless, another study found no association between attempted intubation and long-term mortality (OR=0.91, 95%CI: 0.64-1.23) [Reynolds 2019 129].
Treatment Recommendations
- We recommend the use of mouth-to-mouth or pocket mask ventilation for basic life support providers and laypersons providing resuscitation to adults and children in cardiac arrest caused by drowning (Good practice statement).
- We suggest that bag-mask ventilation can be used by lifeguards or other BLS providers with a duty to respond to a person drowning, on the condition that it is part of a competency-based training program with regular re-training and maintenance of equipment (Good Practice Statement).
- We recommend healthcare professionals follow the ALS treatment recommendations for airway management [Berg 2020 S92].
Justification and Evidence to Decision Framework Highlights
Drowning is the third leading cause of unintentional injury related deaths around the world. Morbidity after initially successful resuscitation is high with many survivors experiencing unfavourable neurological outcomes due to brain hypoxia. Developing evidence-based treatment recommendations to aid those attempting to resuscitate people following drowning is therefore a high priority.
Ventilation is a priority in the drowned patient [Abelairas-Gómez 2019 270; Bierens 2021 205]. Thus, there is need to define the optimal airway management strategy during CA due to drowning (i.e., with or without adjuncts).
Whilst no direct evidence relating to the use of ventilation adjuncts during resuscitation from drowning compared no-equipment ventilation, the review team noted the following indirect evidence:
- One study aimed to compare different airway equipment: TI vs. SGA vs. BVM [Ryan 2021 130]. SGA was associated with lower odds of survival to hospital admission and hospital discharge compared to TI (aOR=0.56, 95%CI: 0.42-0.76) and BVM (aOR=0.40, 95%CI: 0.19-0.86) respectively.
- A drowning case-series study showed complications during ventilation with SGA inserted by an experienced resuscitation expert (Hospital Resuscitation Officer), which was finally removed and replaced with BVM [Baker 2011 675].
- In two studies, TI was associated with worse outcomes in both pre-hospital [Joanknecht 2015 123; Kieboom 2015 h418] and in-hospital settings [Joanknecht 2015 123] in children following drowning. However, TI is also an indicator of the burden of disease in the drowned patient in both adults and children [Garner 2015 93; Joanknecht 2015 123; Kieboom 2015 h418; Reynolds 2019 129; Salas Ballestín 2021 e192].
For basic life support providers and laypersons we found no evidence to suggest a change from current basic life support ventilation recommendations.
For non-healthcare professionals with a duty to respond, such as lifeguards and other volunteers, we did make a conditional exception for the use of BVM despite a lack of evidence. In making this recommendation the Task Force considered:
- that drowning resuscitation is likely to be initially performed by non-healthcare professionals with a duty to assist (i.e. life-guards), but their work conditions (professional/volunteer), availability of equipment and training widely vary both between and within countries;
- that there is a wide variation in the use of ventilation equipment by these groups, including the widespread use of BVM in some regions;
- that there is the need for a BVM treatment recommendation to ensure safe practice in the use of this equipment in this group;
- that bag-mask ventilation can be difficult to perform [Abelairas-Gómez 2019 270; Hood 2014 613; Soar 2019 e826], and requires competency-based training, re-training and monitoring.
- that bag-mask equipment needs to be regularly checked and maintained.
For health care professionals we found no evidence to suggest a change the from the ALS recommendations [Berg 2020 S92].
References
Abelairas-Gómez C, Tipton MJ, González-Salvado V, Bierens JJLM. Drowning: epidemiology, prevention, pathophysiology, resuscitation, and hospital treatment. Emergencias. 2019;31:270-280.
Baker PA, Webber JB. Failure to ventilate with supraglottic airways after drowning. Anaesth Intensive Care. 2011;39:675-677.
Berg KM, Soar J, Andersen LW, et al. Adult Advanced Life Support: 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. Circulation. 2020;142:S92-S139.
Bierens J, Abelairas-Gomez C, Barcala Furelos R et al. Resuscitation and emergency care in drowning: A scoping review. Resuscitation. 2021;162:205-217
Garner AA, Barker CL, Weatherall AD. Retrospective evaluation of prehospital triage, presentation, interventions and outcome in paediatric drowning managed by a physician staffed helicopter emergency medical service. Scand J Trauma Resusc Emerg Med. 2015;23:92.
Hood N, Webber J. Pre-hospital treatment: airway management skills and equipment for aquatic first responders. In: Bierens JJLM, editor. Drowning. Prevention, rescue, treatment. Heidelberg: Springer; 2014. p. 613-619.
Hubert H, Escutnaire J, Michelet P, et al. Can we identify termination of resuscitation criteria in cardiac arrest due to drowning: results from the French national out-of-hospital cardiac arrest registry. J Eval Clin Pract. 2016;22:924-931.
Joanknecht L, Argent AC,van Dijk M, van As AB. Childhood drowning in South Africa: local data should inform prevention strategies. Pediatr Surg Int. 2015;31:123-30.
Kieboom JK, Verkade HJ, Burgerhof JG, et al. Outcome after resuscitation beyond 30 minutes in drowned children with cardiac arrest and hypothermia: Dutch nationwide retrospective cohort study. BMJ. 2015;350:h418.
Reynolds JC, Hartley T, Michiels EA, Quan L. Long-Term Survival After Drowning-Related Cardiac Arrest. J Emerg Med. 2019;57:129-139.
Ryan KM, Bui MD, Dugas JN, Zvonar I, Tobin JM. Impact of prehospital airway interventions on outcome in cardiac arrest following drowning: A study from the CARES Surveillance Group. Resuscitation. 2021;163:130-135.
Salas Ballestín A, de Carlos Vicente JC, Frontera Juan G, et al. Prognostic Factors of Children Admitted to a Pediatric Intensive Care Unit After an Episode of Drowning. Pediatr Emerg Care. 2021;37:e192-e195.
Soar J, Maconochie I, Wyckoff MH, et al. 2019 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. Circulation. 2019;140:e826-e880.