So I got a reverse block during a dive yesterday and I thought I should write about it since it isn't something that happens very often.
Here's the scenario. I had a cold a couple of weeks ago that kept me from diving. As colds go it was pretty uncomfortable. I couldn't clear my ears at all and my sinuses were so blocked that it was giving me headaches. However, it cleared up and I thought I was back in business. Last night I went diving with two friends.
The dive was planned for about 45 min. It was a quick tour along a route that would pass 48 meters maximum depth. We planned to be a little over the NDL's but we were carrying stages of 50%. As technical dives go it was pretty tame.
During the descent everything seemed completely normal. We passed the deepest point and started our ascent. The plan was to follow the profile of the bottom back. At 18m we would do our gas changes and then make a slow swim back to the exit, working off the bit of deco we had along the way.
During the swim back the problems started. At 26 meters it became apparent to me that my sinuses were not clearing properly. I was feeling pressure. At this point I was thinking, "oops, I may need to slow down" but I didn't signal a problem at that point.
At 21 meters I was feeling a lot of pressure and it was starting to hurt. I quickly did my gas change on the fly, which is unusual. My buddy didn't notice me doing this. When we got to 18m there is a platform on the bottom. I got up on it and was hovering over the platform. At this point I was thinking, "this is not going to end well". My head was really hurting now and I needed to stop for a min. My buddy, who up to this point was not aware I was having a problem, signed to me to change gasses. My head wasn't clear because of the pain and I gave him two signs. One was "OK" and the other one seemed to me at the time like I was signalling "something wrong" but I did it with two hands instead of one and my buddy misread it. He thought I was signing to keep his light out of my field of view. It was dark so it's possible he thought this. The third diver was slightly behind me so he didn't see me making signs.
As a response to that, my buddy carried on with the ascent as normal. The third diver followed him and I remained at 18m. I had 15 min of deco showing on my computer at that moment and I knew that I could stay there for a few minutes without it getting out of hand. The pain started to subside somewhat so I thought my sinuses were clearing again. I started my ascent but was lagging behind the other two divers. I decided to let them go because in the dark getting their attention at that distance was probably not going to happen and I needed to focus on my issue. At this point I was basically solo but I could see the other divers turn around a couple of times. They could see my light so just assumed I was being a bit pokey. One of the divers thought I may have had some kind of deep stop that needed to clear.
I got to 12m before I was blocked from going any further again. At this depth at least the deco wasn't going to get any worse on the short term but I really thought that I wasn't going to be able to ascend any further on the short term. I stopped and started hovering and waiting again. The only consolation I really had at that point is that I had made it this far and my problem wasn't going to get worse due to building up large amounts of deco. I should say that this dive is something we do on a fairly regular basis so I still had, in terms of the gas I had with me, about 2 hours of time left to deal with it, aside from the prospect of getting cold.
At this point my buddy came back. He signed from a distance with his light "OK?" and I signed back "NOK". He came to me and asked what was going on. Now I had the next challenge. We don't have a sign to indicate a reverse block so I had to think of something that would get the message across. Fortunately I dive a LOT with this guy and we communicate very well. I made a series of signs that I thought would get it across. They were "Not OK", followed by making a fist that I touched to my forehead and then the sign for "Cramp". He knew that I had a cold the week before and the coin fell immediately. He knew at that point exactly what my problem was.
His response was to sign "OK" (I understand) and then upturned palms (how to proceed?). I signed back "dead slow" and indicated that I wanted to make my way to 6 meters (to clear the deco). I proposed a route along the bottom and he accepted. The third diver, seeing this, probably didn't understand much of what we were signing but as I said I dive with this guy a LOT and we communicate well together.
The issue was I was still at 12m and wasn't going anywhere for the moment. I signed to wait, my buddy said "OK" and then I slowly made my way from 12m to 11.5m. At this point the pain was telling me not to push it anymore. I started waiting again and then suddenly heard a noise in my head, EEEEEeeeeeee, and the pressure was off. I signed to proceed, went to 10m and got blocked again. Again I pushed it a little and heard EEEEEeeeeeee and the pressure was off again.
Bit by bit, using this I managed to make my way to 6m. I held this depth and finished the deco as we swam back in the direction of the exit. We were behind schedule but nobody was in trouble in terms of gas supply. Close to the exit I still had 2 minutes to finish and when that was done I indicated to my buddy to start ascending again. Once again I used the same technique that I had used to get to 6m. Go up as far as I could without being in massive pain and wait for it to clear. It took a while but I managed to get myself to 1.5 meters under the surface before I was blocked enough that I needed to wait for several minutes again.
End good, all good. I made it back to the surface without blowing a sinus and without even causing it to bleed. I think the total delay it caused was about 20-25 min.
The reason I'm writing about this is because of the insights I got.
1) if you have had a cold, don't make your first dive after that deep and technical (duh!)
2) my ability to get from 26m to 12m was crucial for not building up a lot of deco. I got very lucky on that count and if I had blocked on the deep part it could have escalated to the point where I would have to accept injury to my sinuses in order to not run short of time.
3) my initial inability to communicate what was going on at 18m complicated things and caused me to get disconnected from the other divers. I should have intervened quickly when that happened but failed to notice that the signs didn't come across until it was too late. I should have signed "stop" and then everything after that. Signing "stop" would have been a sufficient cue to my buddy to pay close attention to what came after that. We talked about that in the car on the way home.
4) ascending "dead slow" is what PADI has in their OW book and lo-and-behold, it works. That said, nobody would have had to teach me that because the pain was giving my clear instructions
5) the signs "Not-OK" followed by touching the forehead and signing "Cramp" worked to communicate the problem in this case.
6) contrary to what you might think you need to ascend far enough to get some pressure built up so things will clear. It's kind of like walking a knife edge. Go too far and you'll get a barotrauma, don't go far enough and it might not clear by itself. What I found is that by playing with very small changes in depth I could find just the right amount of over-pressure without it becoming too painful. I decided not to "descend" to stop the pain because I thought if I did that more air would enter my sinuses again and it would cause further delays. I'm aware that this example may not be indicative of every reverse-block so just take this with a grain of salt.
I hope if anyone manage to read through all this that they find it helpful.
R..
Here's the scenario. I had a cold a couple of weeks ago that kept me from diving. As colds go it was pretty uncomfortable. I couldn't clear my ears at all and my sinuses were so blocked that it was giving me headaches. However, it cleared up and I thought I was back in business. Last night I went diving with two friends.
The dive was planned for about 45 min. It was a quick tour along a route that would pass 48 meters maximum depth. We planned to be a little over the NDL's but we were carrying stages of 50%. As technical dives go it was pretty tame.
During the descent everything seemed completely normal. We passed the deepest point and started our ascent. The plan was to follow the profile of the bottom back. At 18m we would do our gas changes and then make a slow swim back to the exit, working off the bit of deco we had along the way.
During the swim back the problems started. At 26 meters it became apparent to me that my sinuses were not clearing properly. I was feeling pressure. At this point I was thinking, "oops, I may need to slow down" but I didn't signal a problem at that point.
At 21 meters I was feeling a lot of pressure and it was starting to hurt. I quickly did my gas change on the fly, which is unusual. My buddy didn't notice me doing this. When we got to 18m there is a platform on the bottom. I got up on it and was hovering over the platform. At this point I was thinking, "this is not going to end well". My head was really hurting now and I needed to stop for a min. My buddy, who up to this point was not aware I was having a problem, signed to me to change gasses. My head wasn't clear because of the pain and I gave him two signs. One was "OK" and the other one seemed to me at the time like I was signalling "something wrong" but I did it with two hands instead of one and my buddy misread it. He thought I was signing to keep his light out of my field of view. It was dark so it's possible he thought this. The third diver was slightly behind me so he didn't see me making signs.
As a response to that, my buddy carried on with the ascent as normal. The third diver followed him and I remained at 18m. I had 15 min of deco showing on my computer at that moment and I knew that I could stay there for a few minutes without it getting out of hand. The pain started to subside somewhat so I thought my sinuses were clearing again. I started my ascent but was lagging behind the other two divers. I decided to let them go because in the dark getting their attention at that distance was probably not going to happen and I needed to focus on my issue. At this point I was basically solo but I could see the other divers turn around a couple of times. They could see my light so just assumed I was being a bit pokey. One of the divers thought I may have had some kind of deep stop that needed to clear.
I got to 12m before I was blocked from going any further again. At this depth at least the deco wasn't going to get any worse on the short term but I really thought that I wasn't going to be able to ascend any further on the short term. I stopped and started hovering and waiting again. The only consolation I really had at that point is that I had made it this far and my problem wasn't going to get worse due to building up large amounts of deco. I should say that this dive is something we do on a fairly regular basis so I still had, in terms of the gas I had with me, about 2 hours of time left to deal with it, aside from the prospect of getting cold.
At this point my buddy came back. He signed from a distance with his light "OK?" and I signed back "NOK". He came to me and asked what was going on. Now I had the next challenge. We don't have a sign to indicate a reverse block so I had to think of something that would get the message across. Fortunately I dive a LOT with this guy and we communicate very well. I made a series of signs that I thought would get it across. They were "Not OK", followed by making a fist that I touched to my forehead and then the sign for "Cramp". He knew that I had a cold the week before and the coin fell immediately. He knew at that point exactly what my problem was.
His response was to sign "OK" (I understand) and then upturned palms (how to proceed?). I signed back "dead slow" and indicated that I wanted to make my way to 6 meters (to clear the deco). I proposed a route along the bottom and he accepted. The third diver, seeing this, probably didn't understand much of what we were signing but as I said I dive with this guy a LOT and we communicate well together.
The issue was I was still at 12m and wasn't going anywhere for the moment. I signed to wait, my buddy said "OK" and then I slowly made my way from 12m to 11.5m. At this point the pain was telling me not to push it anymore. I started waiting again and then suddenly heard a noise in my head, EEEEEeeeeeee, and the pressure was off. I signed to proceed, went to 10m and got blocked again. Again I pushed it a little and heard EEEEEeeeeeee and the pressure was off again.
Bit by bit, using this I managed to make my way to 6m. I held this depth and finished the deco as we swam back in the direction of the exit. We were behind schedule but nobody was in trouble in terms of gas supply. Close to the exit I still had 2 minutes to finish and when that was done I indicated to my buddy to start ascending again. Once again I used the same technique that I had used to get to 6m. Go up as far as I could without being in massive pain and wait for it to clear. It took a while but I managed to get myself to 1.5 meters under the surface before I was blocked enough that I needed to wait for several minutes again.
End good, all good. I made it back to the surface without blowing a sinus and without even causing it to bleed. I think the total delay it caused was about 20-25 min.
The reason I'm writing about this is because of the insights I got.
1) if you have had a cold, don't make your first dive after that deep and technical (duh!)
2) my ability to get from 26m to 12m was crucial for not building up a lot of deco. I got very lucky on that count and if I had blocked on the deep part it could have escalated to the point where I would have to accept injury to my sinuses in order to not run short of time.
3) my initial inability to communicate what was going on at 18m complicated things and caused me to get disconnected from the other divers. I should have intervened quickly when that happened but failed to notice that the signs didn't come across until it was too late. I should have signed "stop" and then everything after that. Signing "stop" would have been a sufficient cue to my buddy to pay close attention to what came after that. We talked about that in the car on the way home.
4) ascending "dead slow" is what PADI has in their OW book and lo-and-behold, it works. That said, nobody would have had to teach me that because the pain was giving my clear instructions
5) the signs "Not-OK" followed by touching the forehead and signing "Cramp" worked to communicate the problem in this case.
6) contrary to what you might think you need to ascend far enough to get some pressure built up so things will clear. It's kind of like walking a knife edge. Go too far and you'll get a barotrauma, don't go far enough and it might not clear by itself. What I found is that by playing with very small changes in depth I could find just the right amount of over-pressure without it becoming too painful. I decided not to "descend" to stop the pain because I thought if I did that more air would enter my sinuses again and it would cause further delays. I'm aware that this example may not be indicative of every reverse-block so just take this with a grain of salt.
I hope if anyone manage to read through all this that they find it helpful.
R..
