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Re: Thinning the blood

Posted by James Briggs on December 13, 2001

In Reply to: Re: Thinning the blood posted by TheFallen on December 13, 2001

: : : I wonder about the phrase "thinning the blood" in two ways. First, what do people mean when they use the phrase casually (like, "eating spring greens can be good for thinning the blood"). Second, does it have any technical meaning, as medical people might understanf? Thank you.

: : "Thinning" applies to blood in the same way as it applies to paint or ink or orange juice: thin blood is more liquid (watery) than thick blood. Having thin blood--not too thin, of course--is good because it lowers the risk of heart attack and stroke. That's what both medical people and laypeople mean when they talk about thinning blood.

: Two quick points - I've often seen the phrase "his blood ran thin" used to mean that someone was particularly scared. Not that I'm medically trained, but one of the effects of adrenalin is I believe to constrict surface blood vessels, and reduce blood supply to them - thereby causing the person to become "white with fear", which could have been reasonably presumed also to have been caused by a thinning, paling or dilution of the blood in older times. Of course a less viscous or thinner liquid also will move faster, and again adrenalin does cause a rise in blood pressure.

: The most topical issue regarding thin blood currently is the one concerning the dangers of long-haul economy-class air travel, and the increased risk of DVT (deep vein thrombosis) to passengers. A friend of mine was recently stranded in Turkey having come down with this after just a 4 and a half hour flight. Her blood was thinned with anti-clotting agents, including Warfarin, the rat poison, to an acceptable level before she was allowed to fly home - a process that required daily blood tests and a two week delay. The best advice for air travellers is to take a couple of aspirin before you fly, because of that drug's noted blood-thinning properties, to wear knee-high compression socks/stockings, which increase the pressure and flow in the lower legs, and above all, to walk around briefly every twenty minutes or so, again to promote better circulation. The action involved in using the lower leg muscles is apparently a vital part of a secondary circulatory system, or so I am told.

: As to guzzling spring onions before a flight? I have no idea if this would work... but it might guarantee you a spare empty seat next to you :)

Another use of the term 'thin blood' was/is used to describe someone who has just returned from the Tropics to colder climates. It's said the he/she feels the cold because hers/his blod is still 'thin'.
As a pathologist of 40 or so years standing, with numerous medical publications behind me, I can only say that I have no idea at all what this type of 'thinning' means in haematological terms!
As far as DVT goes, it's now been shown that there is an inherited and testable condition which renders people prone to DVT. It's reckoned that there is on average about 15 such people on board a full Jumbo. The test costs about £250 to perform and please don't write to ask me what it's called - I only quote from a recent letter in the Times by a Consultant Anaesthetist (that's Anasthesiologist in US English).
Good flying and a Merry Christmas.