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Freediving and Safety: possible utilization of SCUBA Diving Regulator to rescue freedivers surfacing in black-out and with severe respiratory issues.
I would like to express my profound gratitude to Tom Ardavany and Bill&Leigh Baker for comments, suggestions, background and professional experience they have shared. In this article I tried to summarize the experiences and know-how gained during several freediving competitions working as Safety Diver and\or Chief of Safety.
Disclaimer: this article is purely for information purposes and must not be used as a reference for any type of first aid or any rescue or BLS activities. There are medical standards and internationally approved procedures by authorized bodies which must be followed in first aid, rescue and BLS activities. Neither the author nor the persons mentioned in the article may be held responsible for the use which may be made of the information contained therein.
First Safety Advice: Never Dive Alone!
Immediately after the death of Nicolas Mevoli during VB2013 competition I had the feeling that something more could have been done in order to save his life, mainly on the platform and mainly from the medics who were in charge on the platform during the competition. This thought did not make me sleep for a long time after the event and even today, after several years, I’m still convinced that his life could have been saved with proper medical support.
I’m not a medic and I do not want to argue or create any controversy on the job done by the doctors on the platform that day (there have been official AIDA investigations and appointed professionals with specific knowledge and academic background have expressed their opinions on how the emergency was handled) but I would like to highlight the fact that probably the rescue protocols, and especially some equipment’s supposed to be available during freediving competitions (till that day), were not effectively used and\or their usage was not considered to be essential for the resolution of this type of cases.
In particular, the breathing supporting maneuvers based on the utilization of the AMBU-BVM mask equipment did not result to be effective for the recovery of Nicolas’s breathing (after one year from the event I had the opportunity to see the video of the accident and there are some evidence which cannot be neglected, especially in the improper usage of the device) and in that case no one decided to try other “practical” solutions which were available on the platform (e.g. diving regulator), probably because the emergency management protocol was not foreseeing the utilization of those devices.
After this sad event and during the preparation of the Vertical Blue 2014, I had the opportunity to talk a lot about the accident with the medic in charge for the VB2014, Mr. Tom Ardavany. Tom is a Registered Nurse and Paramedic from Washington State and he has worked in a Level I Trauma Center and as a flight nurse transporting critical trauma and medical patients via helicopter air ambulance. He also works as a paramedic in the San Juan Islands. As an EMT Instructor for Remote Medical International, Tom has trained military personnel, government agents and body guards in emergency medical response.
During our discussions we have been spending a lot of time thinking about possible utilization of the diving regulator connected to the oxygen tank in order to support a freediver suffering severe breathing impairments and potential lung barotrauma or squeeze. We talked about how and if this very easily available equipment could be really effective in supporting freedivers or spearfisherman surfacing with the aforementioned medical situation, and we have been running drills with the safety crew on how to properly use it. Fortunately during that VB we never had the need to use this equipment.
One year later, 2015, when I was called to be the chief of Safety in the Nirvana Ocean Quest Competition in Colombia, I asked for Tom’s advice in order to properly set-up the emergency management plan. During this event, together with the organizer and the medic in charge on the platform, we decided to introduce the SCUBA Diving regulator in the “emergency management procedure”: in case of black-out victim with severe breathing impairments and possible lungs issues and not recovering after 1 minute of AMBU-BVM mask utilization, the primary option was the utilization of the diving regulator connected to an oxygen tank in order to support victim’s breathing. Fortunately also during this event we never had the need to use this device.
This year, at the very beginning of the VB2016, we had to manage the case of a freediver who came out on the surface with a bad black-out, with severe breath impairments and again we (I was member of the Safety Team, Tom was the supervisor and Bill Baker was the platform emergency responsible) followed the protocol and started immediately supporting his breathing on the platform with the AMBU-BVM mask (the mask in this case was used in a proper way, e.g. adherent to the victim’s face and connected to the oxygen tank). After probably 1 minute we saw that the freediver was not breathing properly and we decided, based on several drills we run before the competition, to switch to the diving regulator: one of the safety divers started breathing oxygen from the diving regulator and performed a couple of mouth-to mouth rescue breathing on the victim. After two attempts we decided to open diver’s mouth and insert the diving regulator directly in his mouth while pinching his nose and starting purging oxygen in his lungs through the regulator valve.
Based purely on the observation of freediver’s reactions, so without any scientific background based on medical tests supporting the following assumptions, we had the opportunity to understand first-hand how effective the utilization of the diving regulator really can be when a diver surfaces with a serious black out and severe breath impairments most probably caused by larynx-spasm and closure of the glottis. The utilization of the AMBU-BVM mask, adopted initially for supporting athlete’s breathing, was not really effective because this device is probably not forcing oxygen with enough positive pressure into the first section of the victim’s respiratory system, which is probably occluded or sealed.
Based on this observations we have agreed that what is probably needed in these cases is positive air pressure to support (or is better saying force) the re-opening of the glottis and larynx and so the arrival of the air flow directly into the lungs. This positive pressure can be generated either by using the second stage of the diving regulator or by performing an effective mouth-to-mouth rescue breathing.
Now we should try to distinguish between two possible real case scenarios:
– First Scenario: You are spearfishing or freediving with a buddy or you are out at sea for a diving training session with an instructor and the only easily available device on the boat is the diving regulator connected to the oxygen tank and (possibly) the AMBU-BVM Mask.
– Second Scenario: You are in an organized event and\or in elite competitions where there are professional medics on the platform and other professional medical tools, together with the diving regulator and AMBU-BVM, are available.
In the first case, if the only alternative available device is the diving regulator, a possible rescue procedure in case the AMBU-BVM doesn’t provide the expected feedback after 1 minute, shall be based on the following very easy steps:
- Second stage of the SCUBA Diving regulator connected to the oxygen tank
- Second stage of the SCUBA Regulator properly inserted in the victim’s mouth: buddy or safety team member shall use his fingers to properly seal the regulator in the mouth in order to not loose air pressure when pressing the purge button
- Nose of the victim pinched in order to not loose air pressure from the upper airways.
- Press the purge valve on the regulator for 2 seconds or until you see the victim’s chest rising meaning that the airflow broke the occlusion in the larynx and the air is flowing in the lungs.
- Repeat until the victim will start breathing autonomously.
- As soon as the airways are cleared, switch back to the AMBU-BVM to support breathing
In the second scenario, if we are in competitions and we have professional medics or emergency management experts on the platform, a “must have” equipment on the platform (apart from the AMBU-BVM mask and other standard equipment’s) could be “a manually triggered valve oxygen ventilating device (so-called MTV), which gives 40-70mm H20 Pressure. The big differences between the diving regulator and the MTV is the better visibility of the breathing pattern and is actually a medical device that can be used for such procedures. The probably reason that AMBU-BVM fails is that BVM has a standard overpressure valve protecting the inflation of the stomach”, as Rik Rosken suggested.
First reflection. Even if the AMBU-BVM mask , as indicated in many first aid protocols and also confirmed from Bill Baker who was the Safety Responsible in charge on the platform at the last Vertical Blue, “remains the tried and true device to provide oxygenation for a hypoxic individual who is breathing inefficiently, and certainly for one who is apneic, we can state that probably the diving regulator has to be considered a valuable support in case the AMBU-BVM device doesn’t provide the expected results after few seconds or in case other professional devices are not available. It just doesn’t replace devices that are designed to ventilate an apneic or unequivocally inefficient respiratory pattern, it just provides additional support or an alternative in case no other solutions are immediately available.”
We have been reported (direct witnesses or written reports) of several cases (at least 4 severe cases happened both in competitions or during deep training) in which the second stage of the diving regulator has been used, sometimes after more than 4 minutes of resuscitation attempts based on the usage of AMBU-BVM mask or mouth-to-mouth rescue breathing: in all the reported cases the utilization of the regulator was found decisive for the recovery of the breathing activity of the victim.
Second reflection. For the overwhelming majority of world-wide free-diving events, the reality is that the oxygen tank connected to the diving regulator is the go-to device because it is currently the predominant piece of equipment easily available on boats or platforms. The introduction of additional equipment’s during freediving competitions and events shall be taken in serious consideration: (1) MTV- Manually Triggered Ventilator devices, (2) CPAP- Continuous Positive Air Pressure or, in case of respiratory failure, (3) Positive Pressure Ventilation (PPV) devices or other supportive devices, mechanically enhanced with the use of the oxygen tank & the right regulator.
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http://www.medicaldev.com/products/mtv-100manually-triggered-ventilator/
http://www.ncbi.nlm.nih.gov/pubmed/9737408
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As suggested by Bill Baker “We can state that in broad scope, the freediver’s problems can be broken down to 4 critical platform complications:
- hypoxia and anoxia which manifests as blackouts – with or without trismus, laryngospasm, or seizure;
- lung squeeze or traumatic lungs barotrauma, resulting in pulmonary edema, sometimes copious and overwhelming;
- a combination of squeeze & blackout, with all that entails;
- respiratory arrest – apnea, not breathing.
We all understand the monumental importance of stopping progression of any of these processes. Now then, as the traditional CPAP is conceived, one must be breathing efficiently and effectively for CPAP to be of benefit. Positive airway pressure is provided to assist in overcoming the physical limits that exist and which ultimately causes insufficient gas exchange at the cellular level. This causes a cascading effect of horrible events in the human body, which can ultimately result in death. The amount of time into the insult (the damage done), as well as proper application of appropriate the tools, will help bridge the gap and stop/reverse this cascade. However, it also takes time for the body to work through that. Sometimes seconds, sometimes several minutes, which is assisted by Safety’s and Medical’s early recognition and proficient mitigation efforts.”
Lesson Learnt from experience: the oxygen regulator can be a good solution to support freedivers or spearfisherman suffering severe black-outs and not recovering after few seconds. Safety procedures defined to manage these type of accidents shall be reviewed and possibly updated because this is not the first time that a life is saved using this very simple equipment. Each device\equipment is a tool that can be utilized in the appropriate circumstance. “But empirically and based purely on observation and consistent anecdotal input, the SCUBA Diving regulator setup on an oxygen tank seems at this point to be a useful and effective device to aid in reaching a positive outcome in case other professional devices are not available and\or are not providing the expected results in few seconds”. During last VB2016 we tested the usage of the SCUBA diving regulator also in the simulated case of a victim suffering a mandibular lockjaw: based on the tests we have done we can assume that, if properly inserted in the victim’s mouth and with mouth + second stage of the SCUBA Diving Regulator system properly sealed, the regulator is capable of forcing air (generating positive pressure) in the lungs even through clenched teeth.
Author: Marco Cosentino, AIDA international and Apnea Academy Instructor, DAN BLS instructor and experienced Safety Diver. Reproduction is authorized provided the source is acknowledged.