Those who know me personally (or are acquainted with me via social media ) may have worked out that I’ve been traveling quite a lot recently, thanks to my work helping to oversee the Game Developers Conference and Black Hat events – both of which have multiple non-U.S. stop-offs.
Yep, multiple long transcontinental flights can be boring at times – if enlivened marginally by lots of Kindle reading (yum, Angry Robot Books) and a little bit of Jetpack Joyride for iPad. And I’m sure lots of you – including myself – have lazed your way through long flights with nary a care in the world. And I’m certainly not looking to spoil your fun.
But since I managed to pick up a blood clot in my leg (aka ‘deep vein thrombosis’, or DVT) on my last long-haul flight (Frankfurt to SFO on May 6th), I’ve been reading a great deal about this relatively unsung danger – sometimes known somewhat incorrectly as ‘economy class syndrome’.
What happens? As a DragonAir page on DVT explains: “The deep veins of the lower legs are situated in the muscles of the calf. Compression of the veins by muscular contraction.. [aid] the return of blood to the heart. If the muscle pump is not working (due to immobilization), the blood flow in the veins may decrease [and] may sometimes [cause clots that] link up to produce a large obstructive thrombus. Immobility in a seated position is an obvious predisposition to DVT as the veins of the legs can get compressed and cause stasis.”
So I figured a friendly blog post to explain what happened, and to alert people why to be careful – but also why not to be too concerned/freaked out – was in order. So here goes:
Having had a bit of a crazy travel schedule in the week leading up to my problem flight (San Francisco to New York for a day, NY to Frankfurt w/train to Cologne, then a 3-hour train ride to Amsterdam, then back to Frankfurt and San Francisco via plane), I confess I wasn’t paying much attention on that final Sunday flight.
As a result of basically not moving around at all – and likely not hydrating enough – during that 11 hour flight, I got a pain in my left calf on the Monday morning. It simply felt like a calf strain – but I couldn’t remember straining my calf when walking around Amsterdam on the Saturday.
The pain went away after I walked to BART to commute into work, but when I commuted the next morning, it didn’t go away and was getting a bit more painful. I could get around, but when I got suspicious and Googled ‘calf pain after long flight‘, I noted that a blood clot was fairly high up the list of possibilities.
Although I didn’t have a swollen leg (yet) and it was quite soon after the flight, my doctor referred me to have an ultrasound on the leg at my local hospital, ‘just in case’. The diagnosis – which can be made in real-time – was a small (but still potentially potent) blood clot blocking a deep vein in my left calf. Oops.
(Side note: as Wikipedia reveals, and I had no idea: ‘There is a strong tendency for DVT to develop in the left leg – about 70 to 90% of the time – “possibly because of exacerbation of the compressive effects on the left iliac vein due to its being crossed by the right iliac artery.”‘ So now you know!)
After some brief panicking, I realized that things were likely going to be fine. The big issue with DVT is that you have blood clots that could potentially move around your bloodstream if detached, and this can lead to pulmonary embolism, where a clot gets stuck in the artery leading from your heart to your lungs. (This condition is how rapper Heavy D died in 2011.)
But my DVT was small (as I could see on the ultrasound) and wasn’t traveling up my leg. And so I got straight on the treatment for DVT, starting off with self-injected heparin every 12 hours, and moving swiftly on to warfarin, which is also used as a rat poison, yum. The goal of these anti-clotting medications is to prevent any further increase in the thrombosis so your body can break it down. But you need regular blood tests to make sure your clotting hasn’t gone _entirely_ to pot – nasty things happen at that point.
Anyhow, my prognosis seems to be just fine. I’ll need to be on warfarin – which isn’t the loveliest drug in the world – for a few more months. But the pain in my calf went away about a week after the medication kicked in, and after two canceled trips – including a European holiday, sigh – my doctor has cleared me to fly longhaul again in a couple of weeks.
(In fact, if you’re taking anti-clotting medication, you’ll be one of the safest people on any flight. But I wouldn’t recommend getting a DVT and getting medicated as a method to avoid subsequent DVTs!)
What You Should Know
So let’s go through some of the things that you – yes, you! – should be doing on every flight you take, and let’s see how I scored. (I know you’ve probably been told to move around, or have the concept at the back of your mind, but let’s bring it closer to the front!)
I’m going to pick a basic anti-DVT checklist for the higher risk at the UK National Health Service’s website, mainly because of the awesome photo they picked to accompany it, also used at the top of this post.
Here we go:
- Walk around whenever you can. [My score: 0/10.]
(I completely failed on this count – having a window seat and a couple sitting next to me, I decided to not get up basically for the entire flight. Bad move – aisle seats and getting up every couple of hours for me from now on.)
- Store luggage overhead so you have room to stretch out your legs. [My score: 4/10]
(I did check my medium-sized luggage, but I had my laptop bag with me. That on its own might have been fine, but the passenger in front of me reclined his seat for the entire flight, and I’m 6 foot 2 and a half. So.. that didn’t help.)
- Do anti-DVT exercises. Raise your heels, keeping your toes on the floor, then bring them down. Do this 10 times. Now raise and lower your toes 10 times. (Repeat.) [My score: 2/10.]
(I actually did flex a _bit_, but not in the right ways, and the above-mentioned legroom issues kicked in.Those with non-long legs should do this, even if they’re not getting up quite as often as they should.)
- Drink plenty of water, don’t drink alcohol or take sleeping pills. [My score: 3/10]
(I didn’t drink any alcohol/take sleeping pills on the flight, or indeed arrive on it particularly dehydrated, but I also stuck to Diet Coke during the flight itself. The attendants give you lots of chances to drink water, so change your normal drinks preferences just for the flight – it makes a difference!)
- Wear loose, comfortable clothes + consider buying flight socks (compression stockings). [My score: 5/10]
(I tend to wear T-shirts and looser clothes for these flights, but I’ll now be sporting knee-high compression socks for my long-haul flights. There are some reasonably stylish brands designed more for athletes like CEP, if you’re worried about looking like an idiot.)
Anyhow, that’s, what, 14 points out of a possible 50? Not good. There’s various statistics on the chances of developing a DVT, and even if “there is about one DVT for every 6,000 journeys that last four hours or more”, why would you catapult yourself up the leaderboard for possible problems? So go ahead, beat my high score, make me happy.
[NOTE: Since my friends have been reading up DVTs, there has been a _little_ bit of paranoia. So let's not get carried away. As the above Patient.co.uk pages notes: "Slight painless puffiness of feet and ankles is common after a long journey and is not due to a DVT."
Slight gimpiness in your muscles after being immobile? You're probably just sore. Worsening limp or calf swelling up more than a couple of days after getting back? Might want to go visit your local doctor.]
If you’re looking for a personal DVT story, there’s a (much better written) written one already, and it’s from someone you might not expect – Ian Anderson of ’70s prog rockers Jethro Tull, whose ‘Confessions of a DVT victim and ten steps for survival‘ is essential reading.
Anderson had a much more serious case of DVT than I did, caused by complications from knee surgery after slipping onstage in Peru (!), but exacerbated by long-haul flights. Nonetheless, his advice is sound — and his humor rather delicious in an understated British type of way.
Other than that, I’m not remotely a doctor, and I would refer you to governmental information sources such as the UK NHS page or the U.S. National Institutes Of Health page, among a _host_ of others, for basic DVT information.
And of course, I’m not saying that you can’t sleep away some of your flight, or have a couple of beers along the way, or even sit in that window seat. Just try to get the majority of the above tips right, and you won’t have a minor but cautionary tale to sport like mine.
[UPDATE: I'm dedicating this blog to Rob Koziura, a work colleague of mine who tragically passed away a few months after I wrote this post, coincidentally through complications from blood clots. Even more tragically, he read my blog before his illness got serious, but wasn't able to get the right diagnosis in time. If your family has a history of blood clotting disorders, or you have shortness of breath in addition to any lasting limb pain, make sure you get help. As has been written about before, the disease can be a silent killer.]