In two recent cases, immediate oxygen first aid resolved symptoms and kept the divers out of the chamber.
Case 1: Solomon Islands
A female diver was on a weekend liveaboard trip. She completed two dives on the first day:
- Dive 1: 33m for 42 minutes, surface interval of 2.5 hours
- Dive 2: 24m for 40 minutes.
Both ascents were slightly faster than normal, she had issues with bouncing and missed all safety stops.
Thirty minutes after the final dive she noted a rash over her abdomen that felt bruised; as well as swollen tender breasts. She was given only 30 minutes of oxygen first aid and the pain and swelling continued when the oxygen stopped. The dive operator contacted the DAN DES Hotline and it was recommended that the diver breathe oxygen for at least two hours and keep up her fluids. She started feeling better while breathing oxygen so DAN advised that they get the diver to a local clinic/hospital for a review and so she could continue breathing oxygen. The local chamber operator was aware of the case and would be ready to recompress the diver if needed. Breathing oxygen completely resolved the rash, but she still had some residual pain in her abdomen, hips and breast. The DAN DES Doctor requested another two hours on oxygen. With the rash not reappearing, the pain gone, and the diver feeling better, she did not need to be recompressed. The following day DAN was advised that the diver had some residual oedema that was not bothering her; the rash was completely gone, she had normal strength in all limbs, no dizziness or nausea. She was advised not to dive for six weeks or fly for a week. She was also advised to have a dive medical review to consider testing for a patent foramen ovale (PFO) as her symptoms were typical of this.
Case 2: Indonesia
A 32-year-old male had completed two technical divers to 40m for 25 minutes on 21/35 mix and completed 25 minutes of deco on 50% oxygen. Immediately upon surfacing he felt weakness and was given oxygen first aid for 25 minutes. His symptoms resolved. However, when he stopped breathing oxygen the weakness returned and he also developed elbow and shoulder pain. When the call came into DAN he had been back on oxygen for an hour with some minor improvement. Likely to be experiencing DCI, the diver was advised to present at the local chamber for evaluation and possible recompression. He arrived at the hospital symptom free and feeling much better having breathed oxygen for around 4-hours by the time he arrived at the hospital. The hospital was not certain of a DCI diagnosis. He was given oxygen at a flowrate of 10 litres per minute, and fluids. When evaluated the next morning he was asymptomatic and advised not to fly for 72 hours. He will refrain from diving until he has received a follow-up evaluation and clearance from a diving doctor.
These two cases are a great example of just how effective oxygen first aid can be when it is provided as soon as symptoms present following diving. It is also highlights that a duration of 25-30 minutes breathing oxygen is not sufficient in relieving symptoms and preventing them from re-appearing. Fortunately, in both these cases, the DES/DAN hotline was contacted relatively quickly, and the operators followed the advice provided by the diving doctors.
DAN statistics tell us that prompt, appropriate and sustained provision of near-100% oxygen by either a demand valve or a high-concentration (preferably at a flow rate of between 12-15 litres per minute) constant flow mask can decrease the severity and longevity of symptoms associated with DCI.
All divers should be asking the operators they dive with, not only if they have oxygen, but how much oxygen they have available, and whether staff are trained in the provision oxygen first aid. All important factors in effectively managing a diver presenting DCI-related symptoms. However, Oxygen is NOT a replacement for medical advice – always call DAN / DES hotline for any symptoms that appear after diving.
As you can see, it is possible to avoid recompression in a Chamber: A little preparedness, and contacting DAN for advice early, can go a long way.