For clarity, the term ‘in-water rescue breaths’ has been replaced with ‘on-water rescue breaths’ as these are given on the water surface.

Drowning Vs Diving

When we talk about the diving casualty, we don’t just mean a drowned patient. Any drowned patient may have some other medical cause to explain why they drowned in the first place – a cardiac or neurological cause, for example – and the same is true for the diving patient. But in diving, we may not mean drowned at all, not in the traditional sense. If a patient has managed to keep their regulator in for the entire ascent, and that regulator is working properly, have they drowned? Or is the bigger issue the subsequent decompression illness from not breathing on ascent, and immersion pulmonary oedema?

Let’s have a look at the guidelines for the management of a drowned casualty.

UK Guidelines and First Aid

Most first-aiders will know the drowning protocol:

• 5 initial rescue breaths

• 30:2 CPR

In the 2021 UK Resus Council guidelines, this hasn’t changed, but there is a bullet point that reads:

Start resuscitation as soon as safe and practical to do so. If trained and able this might include initiating ventilations whilst still in the water or providing ventilations and chest compressions on a boat.

Start resuscitation by giving 5 rescue breaths / ventilations using 100% inspired oxygen if available.

Deakin et al (2021)

European Guidelines

What’s interesting is when you then look at the European Resus Council Guidelines 2021. Here, you’ll find much more detail under the drowning section, including the background research that has informed the guidelines. Of note, there is ‘limited evidence […] to inform the treatment of the drowning victim’ (Lott et al, 2021: 197). Despite this, a table of research includes evidence on in-water resuscitation. Four main points are raised:

• Rescue breaths ‘by highly trained rescue teams with water rescue equipment is feasible’
• These breaths should be given for ‘up to 1 min’ (emphasis added) (10 breaths) ‘before attempting transfer to land’
• No further rescue breaths should be given before landing the patient on land or on the boat
• If a rescuer is alone and has no rescue equipment, they should not begin rescue breaths and should instead tow ‘directly to the shore’ or boat (emphasis added).

(Lott et al, 2021: 199).

Why 10 breaths? This should equate to one every 6 seconds, which is exactly what we would do during continuous CPR with an advanced airway, or during ventilation-only CPR in respiratory arrest (Newell, Grier, & Soar, 2018). (However, this paper highlights the potential for increased survival after 30:2 versus continuous CPR).

Note the difference in wording between the 2015 guidelines (below) and the 2021 guidelines (above):

If a rescuer, in general a surf-lifeguard, finds a non-responding drowning victim in deep open water, the rescuer may start ventilation when trained to do so before moving the victim to dry land or rescue craft. Some victims may respond to this. 

Truhlář et al. (2015).

The 2015 guidelines leaned more towards in-water ventilations than the 2021 guidelines do. The wording was perhaps vague, and left the decision up to the rescuer for when to start ventilations and how long to perform them for, unless the patient was not responding to initial ventilations. In this case, the guidelines emphasised towing the patient to the boat or shore – if it was near – without further ventilations.

The 2021 guidelines, though clearer, do not detail what defines water rescue equipment, or what defines highly trained. Do rescue divers, who are trained at BLS level, constitute ‘highly trained’? Do lifeguards, who frequently practice water rescue, count as highly trained? Or is this term reserved for only ALS-trained healthcare professionals who are also trained in water rescue, or at minimum ILS-trained rescue divers? When we talk about rescue equipment do we mean use of bag-valve-masks and airway adjuncts? Does water rescue equipment include a BCD that is inflated? Translating this advice into diving medical advice is not easy.

British Sub-Aqua Club Guidelines – What Might Change?

BSAC provide dive rescue courses and teach on-water rescue breaths (Cumming, 2011: 56-57), however this information has yet to be updated to the 2021 Resus Council guidelines, and it will be interesting to see what changes when it is updated. The referenced book recommends ventilations while towing, which was not a feature of the 2015 ERC guidelines and makes this book less reliable as a source of information. On the contrary, their Sports Diver student guide (BSAC, 2020: 47), has been updated to stop the practice of giving rescue breaths while towing. Perhaps the biggest change in the next issue will be that a lone rescuer may not be advised to start ventilations in the water, unless help is coming to them and BCDs are considered rescue equipment. Rescuers should also be reminded that the Resus Council advise up to one minute of rescue breaths (Lott et al, 2021: 199). One other change that would be good to see would be a friendly reminder to not perform rescue breaths if this would cause a delay in transport and treatment of the patient – an exemption for some treatments that HCPs should be well versed in. An example of where this might apply would be where the time it takes to give rescue breaths is longer than the time it would take to evacuate this patient to the shore or a nearby boat.

UKDMC – Are Times Changing?

This statement from the UKDMC (Edge and Wilmshurst, n.d.) states that there is a higher chance of neurological damage, despite an apparent improvement in survival rates, when on-water resuscitation is performed. Remind anyone of the trial results from something else we do in resus? They also note that even when lifeguards are performing in-water ventilations, the patient aspirates, and the rescuer tires. And this was in a pool… Now imagine waves of salty water lapping over both patient and rescuer. Multiple other issues arise – ventilation may be restricted by diving equipment that covers the chest, rescuers will be unable to assess chest rise and fall due to this equipment, and even those of us who are HCPs won’t have regular practice, especially in the special circumstances of resus of diving patients.

This doesn’t even consider that in the absence of pulse checks (due to wet/dry suits covering the neck), the rescuer is unable to assess respiratory versus cardiac arrest, and may be at risk of confirmation bias – that casualty who was in cardiac arrest when they surfaced, they have a pulse on the boat so we must have got them back, right? Or, that unconscious patient who wasn’t breathing is breathing now, so we saved them – or were they just breathing so shallow that, in amongst the noise of the boats and the waves, and with all that equipment on them, we could not look, or listen, or feel. Realistically, this may be one reason there is limited evidence. It will be interesting to see how diving organisations respond in the future and whether their guidelines continue to change.

References

British Sub-Aqua Club, 2020. Sports Diver: Student Guide. BSAC.

Cumming, B. 2011. Safety and Rescue for Divers, BSAC: Cheshire.

Deakin, C.D. et al (2021) Special Circumstances Guidelines. Available at: https://www.resus.org.uk/library/2021-resuscitation-guidelines/special-circumstances-guidelines (Accessed 11/12/2021).

Edge, C. And Wilmshurst, P. n.d. The Rescue of a Diving Casualty – A Discussion Paper. Available at: https://www.ukdmc.org/wp-content/uploads/2017/04/PW-and-CJE-position-paper-on-diver-rescue.pdf (Accessed 11/12/2021).

Lott, C. et al (2021) ‘European Resuscitation Council Guidelines 2021: Cardiac arrest in special circumstances’, Resuscitation, 161, pp: 152-219. Available at: https://cprguidelines.eu/assets/guidelines/European-Resuscitation-Council-Guidelines-2021-Ca.pdf (Accessed 11/12/2021)

Newell, C. Grier, S. And Soar, J. (2018) ‘Airway and ventilation management during cardiopulmonary resuscitation and after successful resuscitation’, Critical Care, 22(190). doi: https://doi.org/10.1186/s13054-018-2121-y

Truhlář, A. et al (2021) European Resuscitation Council Guidelines for Resuscitation 2015: Section 4. Cardiac arrest in special circumstances. Available at: https://ercguidelines.elsevierresource.com/european-resuscitation-council-guidelines-resuscitation-2015-section-4-cardiac-arrest-special#BSPECIALENVIRONMENTS (Accessed 11/12/2021)