this erudition is the list at its best
many thanks
marya
> from: David Jobson <[log in to unmask]>
> date: Wed, 18 Feb 2004 15:28:37
> to: [log in to unmask]
> subject: Re: BP Cuff size
>
> > Does anyone have the measurements or recommended sizes of the bladders
> > of BP cuffs - preferably evidence based. JNC 7 recommends that the BP
> > cuff should encircle at least 80% of the arm, but I'm not sure if it
> > means that 80% of the length of the arm should be covered or 80% of the
> > arm circumference.
>
> Circumference
>
> > Is there any data on how much cuff size really
> > affects BP measurements?
> >
> > Leon
>
> Small cuff leads to over-estimating BP, by up to 40mm if my
> memory serves me right. Over-sized cuff is claimed to cause
> too low a reading - BUT when I did some work for WHO on this
> I was unable to find any convincing evidence of this but it was
> in about '86 - I suspect it was handed down wisdom!
>
> I can not see, and I see Midge agrees, that having a bit of overlapping cuff
> makes not a tiny jot of difference.
>
> Too narrow a cuff (?10cm or below) also leads to overestimation,
> but you can't buy the too narrow!
>
> I recently threw away all the photocopies from that research!
>
> I have used 13 x 33 for many years which fits >95 of adults
> The 12 x 26, as in the chart below, is much too small for many
> patients I find.
>
> With obese adults the forearm is perfectly OK.
>
>
>
> Recommended bladder dimensions. Data reproduced from O'Brien E, Petrie J, Littler WA et al. Blood Pressure Measurement: Recommendations of the British Hypertension Society. London: BMJ Books, 1997
>
>
> --------------------------------------------------------------------
>
> Dimensions (cm) Subject Maximum arm circumference (cm)
>
> --------------------------------------------------------------------
>
> 4×13 Small children 17
> 10×18 Medium sized children
> Lean adults 26
> 12×26 Majority of adult arms 33
> 12×40 Obese adults 50
>
> --------------------------------------------------------------------
>
> Accurate readings may be obtained in adults with arm circumferences greater than 50 cm by placing a cuff with a 40 cm bladder so that the centre of the bladder is over the brachial artery. All dimensions have a tolerance of ±1 cm.
>
> Gareth Beevers, Gregory Y H Lip, and Eoin O'Brien
> ABC of hypertension: Blood pressure measurement
> BMJ, Apr 2001; 322: 981 - 985.
>
>
>
> More basic instructions can be found in a book I wrote for the developing world
>
> Detecting pre-eclampsia: a practical guide
>
> 1992 Ref. WHO/MCH/MSM/92.3 - 46 pages
> Dr Richard Guidotti, Maternal Health and Safe Motherhood Programme, WHO, Geneva
> Dr David Jobson, Formely Obstetrician/Gynaecologist Consultant,
> Ministry of Health, Gambia,
> presently General Practioner Leiston, Suffolk, UK.
>
>
> David Jobson
Dr Mary Anderson MRCGP
Heaton Moor Medical Centre
SK4 4NX
tel 0161 432 0671
fax 0161 442 1025
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