Monday, 15 February 2010

GLOC's PFO and where things are now

The first part of this was originally written in October once I got back from Malta and had my PFO test.

Well, I have been doing some fairly big dives with a PFO but I didn't know about it!!

The last dive I did in Malta (9 August 2009) was 15/40, 50% and 100%, 30mins at 63m and 65mins of deco from 21m up including 35mins on 100% at 6m (god that was boring!). The dive was really uneventful (apart from some cracking photos!) and when I surfaced I didn't have any issues. Handed the stages up to the boat and then climbed up the ladder onto the rib. No issues at this point. Dekitted and then sat on the tube of the rib and noticed some visual disturbances but no headache or muscle pains or anything else. Nothing too major, just a slight blurring, the sort of thing you get when you look at a light bulb too long.

I didn't say anything to anyone, just thought it was one of those things...besides no other symptoms. (Mistake 1)

We then went back into the harbour (20mins or so from surfacing) and during this period the visual disturbance disappeared, probably around 5mins or so, and I thought, no worries, just something transient.

Pulled alongside and then started to unload the boat which entailed lifting the kit from the RHIB up onto the quayside and then onto the back of a flatbed. At this point, the disturbances came back, again no other issues with regards to DCI. Mistake number 2, I didn't say anything to anyone. About 20 mins later, these disappeared again, so again, I thought no worries at the moment, but I probably need to see someone when I get back to the UK (last dive of the trip, flying home the following morning).

So, I get back to the UK and book an appointment with my GP and explained what had happened. This was quite funny as I knew far more about the link between PFO and migraine and PFO and DCI. He was going to put me in for an ECG which I said would be a waste of time that I needed a ultrasound test. Ended up him asking me to go away, let him know what he needed to do with regards to a PFO test and he would refer me!

I didn't do all of that. I spoke to a couple of people who put me in touch with Mark Turner at the Bristol Heart Institue who said that I probably did have a PFO even though I didn't have any other DCS symptoms but the only way would be to complete a test. To do this, I could wait 10 weeks or so for an NHS test once he had the referral paperwork or pay ~£500 for a private appointment in a week or so. Being the impatient person, and the fact I now had 2 T1 weekends that I was going to be diving on, I went for the private test.

I went up to Bristol 2 weeks ago to have the test which entailed doing a baseline scan of the cardiac area whilst lying on my left side and using an external ultrasound scan (Transthoracic Echocardiagram). Once this was done, I had some saline/blood mixture mixed with small amounts of air injected into my left forearm and a scan taken without conducting a valsalva clear. There were some bubbles present in this.

Then I was asked to do a big sniff (builder's sniff, Mark called it!!) halfway through the injection of more blood/saline/air and Mark immediately said "You have bubbles there" :( Then there was a valsalva for 15 secs which makes your head hurt, but there was limited crossing of bubbles with this, 2 more valsalvas with limited success and then another sniff, with more bubbles but not as much as the first sniff.

This is the [URL=""]sniff test [/URL]video clip! <
So, I have a PFO :) The stats Mark gave were something like 1:4 people have a small PFO but because most people don't dive this isn't an issue, however, there are major indications that a PFO increases a risk of stroke as it allows a clot to transfer from the veinous side of the blood system to the arterial (the same way bubbles do). 1:10 have a moderate PFO and about 1:100 have a PFO the size of the one I have!! However, the PFO can be fixed and there is a no-dive period of 3 months following the op when a very large percentage of PFOs are closed.

Mark thinks that the visual disturbances were caused by bubbles forming on the retina as the disturbances were not indicative of a bubble in the neural area where nerves would have been blocked/trapped etc.

Mark is in the process of writing up a report for my GP, so that I can get an op to fix it. I will not be doing any trimix diving until it is fixed and the only other diving I will be doing will be inside air NDL limits using high FO2 and using O2 at the 6m stop when I get anywhere close to that.

Getting bent knowing that I have a PFO is somewhat stupid so I am not going to push it even though diving means so much to me.

Looking back, I can make one of two assessments of why I haven't been bent...

1. I have been lucky...
2. The deco I have been doing has been good at stopping bubbles growing and the O2 has sorted the remaining stuff out.

What was different about the dive I did in Malta was the time it took from surfacing to getting back on shore. Most of the diving in the UK I have done has been done with a hardboat 1-3 hours from shore so I haven't had to hump kit around so close to the surfacing time. Simon Mitchell at EUROTEK last year said that the worst time to be doing anything strenuous is around 30mins from surfacing. Guess what!

So, you don't know you have a PFO until you

a. have a test,
b. get bent, then have a test,
c. have a stroke, then have a test.

I have done something like 10 T2 level dives and 50 plus T1 level dives and nothing has presented itself, until this time. Fortunately, when it did present itself, it was a fairly minor thing ;)

It has been hard for me to not go diving but then I have the rest of my life in-front of me, and to do something because it is there and bugger the consequences is just plain stupid for all concerned.

Hopefully you will have got something out this post....not least, own up to your buddies that something is wrong and then they can do something if you go tits-up quickly! Denial isn't just a river in Egypt! :D
Update 15 February.

Last Friday, 12 February, I went into Bristol Heart Institute to see Dr Mark Turner and get my PFO closed.

I will update this in more detail shortly but suffice to say that I had a rather large PFO 7-8mm x 12mm. The average is around 3.5-5mm.

I need to go back in 6 weeks time to make sure things are healing and then 6 weeks after that to have a bubble test before I can go back diving.

In the 6 months since the bend, I have been diving twice, once for Scuba Santas in December, the other teaching UW photography in January. I really miss it and want to get back in the water. Hopefully I can, as I have a week booked to dive Shetland in July...