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I've made comments here in the past about chairs being lethal, but I had still underestimated the threat considerably. This is a warning to anyone else who has any symptoms like mine.

I've suspected for a few months that I might have deep vein thrombosis from spending long hours immobile at a computer while concentrating on building complex software. This morning that was confirmed by a blood clot breaking free and lodging somewhere in the entrance to the lungs. It was a battle for survival with very little oxygen getting into my system as I had to breathe like a racing cyclist sprinting up a steep hill at the end of a race: ordinarily if you're not actually exercising that would make your teeth tingle within half a minute, but instead of that today my hands went increasingly numb and I could feel everything else gradually begin to shut down too. I didn't think I was going to survive this as it just kept getting worse, but kept on breathing as hard as possible in the hope that something might change in my favour. After five minutes, I decided that Aspirin was the only hope and got to a box after perhaps another two to three minutes, but by the time I'd taken a few of them, the oxygen was already beginning to get through better without needing their help, and within a couple of minutes of that it was clearing up fast, in the end leaving the doctor with absolutely nothing to measure. This is not the recommended way to get rid of a blood clot: you're supposed to dissolve them out over six months with chemicals. It's also not the way these things normally resolve: ordinarily the blood clot doesn't magically disintegrate like that, but either kills or causes lasting damage that takes months to recover from.

I now suspect that three or four other events over the previous few years may have been caused by smaller blood clots reaching the lungs where they caused me two or three minutes of much lesser alarm with things not feeling right but without any shortage of oxygen. This latest event was in totally different league, with symptoms leading up to it including having difficulty sitting down for even short lengths of time, and with my feet or one foot swelling up, though most of the times that happened it could have been put down to the long hours at which I've been standing working on a computer to avoid sitting, but the night before last I woke up with a swollen left foot which hadn't been that way when I went to bed. I've had a pain that comes and goes for many months deep in the middle of the left side of the derrière, and that was the worst it had ever been last night. There's now no pain there, so it's a fair bet that the clot shifted from there.

Anyway, chairs are lethal if you sit in them for too long without moving, and when you're frequently absorbed in programming, you may be moving very little and storing up the same kind of trouble. If any of this sounds like anything that's happening to you, you should take action against it now. Ideally, all people who work many hours a day at a computer should have a "walking desk". The biggest mistake I made was to think that the problem would, if it was DVT, go away over time if I didn't work so much while sitting, but there was already at least one clot there and it simply did not dissolve away. I was very lucky to survive this one - it was right on the edge and it would have been easy just to give up and die. I fought hard to survive even though it was beginning to look hopeless.

I am sorry to hear about your experience and I am glad that you are now better.

I have been especially concerned myself with how much time I've been sitting in my life (and still am!). Sitting in a chair is one of the worst thing that you can do to your body and modern medicine is only starting to take notice.

Take lots of break to stretch and walk around the house.

You have no idea how lucky you are. I hope you got yourself checked, as more than one clot at the same time may have appeared. Clots cause ischemia, depriving cells of oxygen, and that kills them. The clot may have just moved further, allowing for blood flow to reach a bunch more of peripheral capillaries, but still be there. It's also important to know when to use and not use aspirin, because if you have a low platelet count, it could be worse if you do it without medical supervision (in a hospital they'd give you heparin or warfarin while standing by with vitamin K for emergencies, and then prescribe you clopidogrel for life), but when it's certain that it's a clot, aspirin is usually the best first course of action.

I can't sit still, so that's probably what's been saving me from having the same happen to me.

If you have the possibility, I'd recommend getting yourself an automated standing desk and use it to switch positions several times a day - it also helps with your neck, back and general posture. I have one at the office, though it's where I spend the least amount of time. Sometimes I'm even more productive while I'm standing - YMMV.

Hope you get better.

FWIW, my sister managed to get thrombosis while on a bike, and her job has her running around all day (she's a hospital doctor). The thrombosis hit once just when she was arriving at work. And good thing, because she lost consciousness while walking through the door, so she could be helped immediately.

But yes, current advice is to not sit for more than an hour straight, and if you are merely getting up to go to the bathroom. At work, my desk is adjustable, and I can turn it into a standing desk if I want to. Which I probably ought to do more often.

nullplan wrote:FWIW, my sister managed to get thrombosis while on a bike, and her job has her running around all day (she's a hospital doctor). The thrombosis hit once just when she was arriving at work. And good thing, because she lost consciousness while walking through the door, so she could be helped immediately.

But yes, current advice is to not sit for more than an hour straight, and if you are merely getting up to go to the bathroom. At work, my desk is adjustable, and I can turn it into a standing desk if I want to. Which I probably ought to do more often.

Moving around is no guarantee that it won't happen, it just helps prevent an increase to that person's natural thrombosis chances as a lot of other factors are involved like, for instance, the platelet count, medication, dietary habbits, sleeping position... I know of someone who has been popping clots like rabbits pop offspring since their late teen years and said person is not sedentary. However, for us, coders, the chances increase because our sedentary habbits tend to put us in positions that constrict vessels or twist them into positions that cause high disturbance to the usually smooth blood flow, and that's one of the main non-artificial sources of thrombosis. So, everybody, get that @$$ shaking.

Sorry to hear that, I'm glad that you're still with us. Thrombosis is scary stuff.

I'm also prone to sitting at the computer for hours in a row, in all sorts of contorted positions. DVT is not the only risk, for example there are also RSI, back problems, eyestrain and even mental problems. I use a tool, RSIBreak, that grays out my screen and blocks input for two minutes every 15 minutes, and ten minutes every hour.

I use that time to walk around a bit, drink some water and stare into the distance (I'm lucky to have a window with a nice view and can see things 25 km away in good weather). The ten-minute breaks are useful because I use that time to organize and clean. Before, especially during my more depressive episodes, my home would turn into an unlivable hellhole for weeks. Now it's just slightly messy.

And, of course, exercise. I'd love to have a dog that I'd need to walk at least three times a day, but for now I try to go on a 30-minute walk every day. I also try to take the stairs at least once a week, but with 22 floors that may not be advisable to everyone

Wukl wrote:I'd love to have a dog that I'd need to walk...

I always tell people I don't take my dog for a walk - he takes me for a walk.

Thanks for all your kind comments.

BigBuda wrote:The clot may have just moved further, allowing for blood flow to reach a bunch more of peripheral capillaries, but still be there.

It seems more likely now that it was multiple fragments of a clot acting like a shotgun and causing multiple blockages before disintegrating further and clearing. Also, more blood must have been getting past than I'd realised because there was still enough oxygen getting to the brain which must have been prioritised, while the limbs were starved of it - I'd have blacked out otherwise. Anyway, I'm fine now and the danger is now much lower than it was before this happened.

Further thoughts for others who may be at risk:-

An @$$-massage chair might be a better solution than a walking desk, but it would need to have a very slow mode so as not to be distracting.

Having a small tank of oxygen in the house could be a good precaution to help survive long enough for a paramedic to arrive.

It would be worth setting up a tape recorder with a recorded message to play down the phone to call a paramedic to your house. I couldn't make a phone call until after I'd started to recover.

DavidCooper wrote:Thanks for all your kind comments.
Having a small tank of oxygen in the house could be a good precaution to help survive long enough for a paramedic to arrive.

It would be worth setting up a tape recorder with a recorded message to play down the phone to call a paramedic to your house. I couldn't make a phone call until after I'd started to recover.

You can't just use a tank of oxygen without precaution. Pure oxygen is actually damaging to the lungs, so care must be taken. There are specific oxygen ratios applicable depending on the status of a person.

Having aspirin and water always at hand would be much more advisable.

The recorded message is a good idea, though.

Yes - the oxygen thing is indeed hazardous and not something doctors would ever help anyone set up for this kind of eventuality, but it's mostly a fire risk, and you certainly don't want to keep the stuff in the house. At atmospheric pressure it's not harmful even at 100% for a short time so long as you actually need it, but becomes dangerous at depth when diving as you're effectively getting a much higher concentration than that. It's also prohibitively expensive unless you get the compressed oxygen sold for welding which apparently can be used for breathing in a medical emergency (best done by filling a bag and then breathing from the bag, thus avoiding the need for any other expensive equipment) but which should never be inhaled otherwise. It's an absolute last resort only suited to those who fully understand what they're doing. Overall it's probably a bad idea so I must unadvise it.

Edit: the more I look into this, the less attractive the idea looks. Oxygen is just too explosive - when it hits the wrong things it just ignites.

Yeek! Thanks for the warning, DavidCooper. I find myself getting up pretty often these days, my body sometimes getting uncomfortable in less than half an hour, but sometimes not. I do spend several hours a week in light exercise, (elevtric bike with pedal assist,) so maybe I'm all right.

eekee wrote:I do spend several hours a week in light exercise, (elevtric bike with pedal assist,) so maybe I'm all right.

Exercise doesn't undo the damage, so it's a matter of being careful not to sit for too long at a time. If you're getting actual pain at a specific location which persists for months which is aggravated by sitting, ask a doctor for a D-dimer test to check for elevated levels of a breakdown product of blood clots. Incidentally, I've just read a study into wheelchair users where 44% of the ones they tested had DVT, so that gives you some way to gauge the risk if you sit for many hours a day without exercise breaks.

DavidCooper wrote:Exercise doesn't undo the damage, so it's a matter of being careful not to sit for too long at a time. If you're getting actual pain at a specific location which persists for months which is aggravated by sitting, ask a doctor for a D-dimer test to check for elevated levels of a breakdown product of blood clots. Incidentally, I've just read a study into wheelchair users where 44% of the ones they tested had DVT, so that gives you some way to gauge the risk if you sit for many hours a day without exercise breaks.

Thanks. I don't get persistent pain, so that's a relief. My symptoms are more like peripheral vascular disease (PVD) which is associated with diabetes. I've had a bit of a problem regulating blood sugar for years, but it got really bad last week, so I've been reading up on diabetes. I'm pretty sure I've got it but it must only be type 2, and I think I've figured out a blood sugar management strategy which will work with my poor memory, so I'm not feeling too bad about it. My plan for the PVD is simply to keep the blood flowing with techniques I was already using, but maybe do them a bit more.

DavidCooper wrote:At atmospheric pressure [oxygen is] not harmful even at 100% for a short time so long as you actually need it, but becomes dangerous at depth when diving as you're effectively getting a much higher concentration than that.

Oxygen toxicity is an issue even at one atmosphere.

The thing is to take movement breaks. No matter if you are at the office, at home, in a hospital bed, or on a long-distance flight: Taking a walk now and then is beneficial, not just because of risk of thrombosis.

Also, from personal experience -- "taking your brain off the subject" for at least five minutes every hour actually increases your productivity by a significant amount.

Desks that allow you to switch between sitting and standing are also a good idea, as is sitting on exercise balls, as either helps to avoid sitting slouched in one position for too long.

Solar wrote:Oxygen toxicity is an issue even at one atmosphere.

Only after a few hours. It would be safe during the time waiting for a paramedic to turn up, except that trying to apply it the wrong way while in that state would likely lead to the the user setting himself on fire and just adding to his woes, which is why I abandoned the idea.

Desks that allow you to switch between sitting and standing are also a good idea

I've just read something that says you can get DVT from standing too. A walking desk is a better solution, though it would me more environmentally friendly to be able to walk around while programming, and that means wearable computers. I hope we don't have to wait much longer before we have those.

I've also found that there's no decent massaging cushion available to make sitting safer, so that's something that needs to be designed and experimented with before being produced through Kickstarter.

By the way, the problem that I've had with sitting down for even short lengths of time also appears to be diminishing a bit now just by taking Aspirin, so I may be able to avoid going on anything stronger if this progress continues. This was not the normal kind of DVT with one big blood clot reaching the lungs, but a "pulmonary embolism shower" of small clots.