Staying safe during remote-location diving
Last updated: 18/01/2018
Yachting and diving go hand-in-hand; one lets you enjoy being on the ocean, while the other lets you enjoy being in the ocean. It’s no surprise therefore that many yacht owners and guests look to enjoy some diving during their time on board, with some charter trips are even advertised as ‘yacht diving breaks’ with full-time instructors as part of the crew.
This ever-increasing trend led us to take a look at the world of diving medicine and how it is becoming an increasingly important reality of remote diving in the superyacht industry.
Decompression sickness after scuba diving
You may have heard of people getting ‘the bends’ after diving; this is the informal term for decompression sickness (DCS), a syndrome caused by bubble formation and growth in the blood and other tissues, usually due to inadequate decompression – the inability of the dissolved inert gas to leave the tissues during the ascent phase.
Since bubbles can form in any body tissues, DCS can produce many symptoms, and its effects may vary from joint pains and skin rashes to paralysis, and in very rare cases, even death.
The risk of a scuba diver developing decompression sickness (DCS) is an accepted hazard associated with compressed gas diving, although DCS is actually a relatively rare occurrence, estimated to be around 1 in 10,000 dives, at least in recreational diving.
There are techniques, procedures and approaches to help mitigate the risk in recreational diving. If a diver is stricken by a severe case of DCS, and is not promptly and adequately treated, the condition could lead to permanent residual symptoms, or even disability.
Hyperbaric medicine on board yachts
Diving in remote diving locations is usually attractive due to either pristine conditions, or the remoteness itself. Under these circumstances, access to adequate hyperbaric medical facilities is rarely a realistic option. Where recompression therapy becomes a medical necessity, treatment often needs to begin within hours to be effective.
When remote diving conditions involve a likely decompression risk, the availability of an on-board recompression chamber and properly trained medical staff might be appropriate. Recompression therapy is a medical treatment, provided in a hyperbaric chamber, in which oxygen is delivered to an injured diver (who is then regarded as a medical patient) whilst being exposed to pressures, equivalent to between nine and 18 MSW (metres sea water). In rare cases, treatment pressures could be as high as 50 MSW.
Pressurising the patient and then having them breathe pure oxygen reduces the size of the inert bubbles as they are dissolved back into the bloodstream. While in-water recompression (IWR) is often cited as an emergency treatment plan for remote dive operations, S.O.S. Medical Group advises that the reality is a limited option that carries significant safety risks and logistical challenges.
As such, it has created the SOS Hyperlite™ system; a portable, lightweight transport chamber to meet the needs of smaller vessels. Twin-lock chambers are the preferred medical devices to deliver such treatments. However, such chambers require larger vessels, due to size and weight considerations.
Crew preparations for remote diving
Diving expeditions in remote locations are not simple to run, and even a single diving day requires several trained and qualified personnel to ensure everything runs smoothly. In addition, any medical complications need to be dealt with in an efficient manner.
Francois Burman of Divers’ Alert Network (DAN), took us through the first steps of the risk assessment and key points that must be carried out and considered before any dive:
- How many divers will be on board and what is the expected number of dives?
- What is the expected medical and physical fitness of the divers?
- What type of diving is intended: Technical, mixed gases, rebreather or scientific diving?
- How deep will you be diving and what are the expected dive times, or in other words, are the dive exposures (depth/time) expected to be mild, moderate or aggressive?
- Where will you be diving and how remote is this likely to be; both regarding the availability of emergency medical services, as well as time and distance to the next level of medical care?
- Will there be a doctor on-board or available in real-time via a telecommunications link?
- How far is it to the nearest definitive medical facility where there is a capable hyperbaric treatment facility?
He advised that an injured diver is a medical patient and not just a diver. A doctor with a basic knowledge of diving medicine must therefore be on hand to make any medical decisions. Treatment may not necessarily or exclusively include recompression.
Francois said, “Keep in mind that there may be jurisdictional issues, such as diving within a sovereign country’s waters. These can include the practice of medicine – especially if you are going to rely on a local doctor to assist. Some countries require a medical doctor to be licensed in that country to be able to practice medicine – this might apply to the on-board doctor or the telemedicine doctor. In some countries, if you’re registered or licensed to operate a vessel under a sovereign county’s flag, then you might be exempt from this jurisdictional issue.”
Francois continued, ‘The most important aspect to consider, prior to making any diving decision, is whether there is a sound culture of safety on the vessel, so as to minimise any decompression injuries, accidents or incidents.
“The vessel should have sufficient and appropriate first-aid supplies, including surface oxygen kits with sufficient oxygen supplies and any other medical support equipment used to treat divers until reaching a place of professional care. This implies that the diving support personnel need appropriate and in-date training to be able to administer basic medical support. And remember that DAN is available 24/7/365 anywhere in the world – be sure to keep the relevant hotline number handy for the region you intend travelling to.”