This article is from the Big Folks Health FAQ, by email@example.com (Sharon Curtis) with numerous contributions by others.
Large-size blood-pressure cuffs:
It is vitally important that they use large-size blood pressure cuffs,
since conventional-size cuffs give high blood pressure readings when
they are used on large arms. It may also be possible to measure blood
pressure in the radial or ulnar artery -- use a regular-size blood
pressure cuff but put it on your forearm, rather than your upper arm.
It's apparently harder to hear, but it can be done.
Several suggestions. If they don't have them, you could try two
gowns, one on the front, and one on the back. They might make you
a little hot, but will preserve modesty.
If you're nifty with a needle, you could make your own, or you
might be able to buy one.
An ad in the Spring '95 issues of Radiance declares:
Supersize Hospital Gowns - Don't get caught without your own.
Check/M.O. for $30 to NAAFA Feminist SIG, c/o Lynn Meletiche,
2065 First Ave., #19-D, Dept. RM, NY, NY 10029, USA (212) 721-8259.
Allow 4-6 weeks for delivery.
Alternatively, try (again, in the US)
NAAFA, P.O. Box 188620, Sacramento, CA 95818, tel. 916/558-6880 (Mon-Thurs).
MRI (magnetic resonance imaging) machines:
There do exist open-sided machines, where only the head slides under the
mechanism. These are for people that are large or claustrophobic. You
might need to call around to see where this service is offered.
Alternatively, depending on what you need the machine for, it might be
possible to look at your body in other ways, for example a CAT scan.
The Philips Medical Systems' Gyroscan T5 is designed to
handle patients up to approximately 500 pounds and is in use in many
hospitals around the US. Give them a call and they can tell you the
location of the nearest hospital that has one.
Their number is (800) 526-4963.
Also see the scales section in the resources FAQ for how to be weighed if
you are heavier than the highest number on the scale.