Art & science clinical skills
36 january 20 :: vol 30 no 21 :: 2015 NURSING STANDARD
How to measure blood
Rushton M, Smith J (2015) How to measure blood pressure manually. Nursing Standard. 30, 21, 36-39.
Date of submission: October 14 2014; date of acceptance: February 5 2015.
Rationale and key points
This article aims to help nurses to measure blood pressure (BP)
manually using an aneroid sphygmomanometer.
BP measurement is an essential clinical skill, and nurses must
be competent in performing this procedure and taking
Nurses should be aware of manual BP measurement techniques
and understand the patient and environmental factors that may
result in inaccurate readings that could compromise patient care.
Nurses should regularly undertake manual BP measurement to
ensure they remain competent to perform the procedure.
Clinical skills articles can help update your prac tice and ensure it
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and write a shor t account of:
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Melanie Rushton Adult lecturer, University of Salford, Manchester,
Joyce Smith Adult lecturer, University of Salford, Manches ter, England.
Correspondence to: firstname.lastname@example.org, @ RushtonMel
aneroid sphygmomanometer, blood pressure, clinical procedures,
clinical skills, vital signs
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Ensure that the appropriate equipment is available
and in good working condition. This includes:
– A sphygmomanometer (working and
– A stethoscope.
– An appropriate-size BP cuff (British
Hypertension Society 2009) (Table 1).
– Bactericidal soap or bactericidal alcohol
– Detergent wipes (no alcohol).
– An observation sheet or early warning score
chart to record BP.
Before you begin, ensure you know how to feel
for the radial and brachial pulses.
1. Wash your hands using bactericidal soap and
water or bactericidal alcohol handrub.
2. Ask the patient or visually check if they have
had any trauma or surgery to their arm or
have an intravenous infusion in progress. If
[Q - ok to add: ‘they have, or if’ ?] there are any
contraindications, use the other arm. If it is not
possible to use either arm, the thigh can be used
by applying a thigh cuff to the mid-thigh area.
3. Ensure the patient is relaxed and seated
comfortably, with their back supported and feet
uncrossed and ﬂat on the ﬂoor.
4. Ensure the BP cuff is the correct size for the arm
(British Hypertension Society 2009) (Table 1).
5. Check that the patient’s arm is not restricted
by any tight clothing. Support the arm with a
pillow, ensuring that it is level with the person’s
heart (midsternal level).
6. Wrap the BP cuff around the patient’s bare arm.
The cuff should be positioned 2-3cm above the
brachial artery (Figure 1).
7. Ask the patient not to talk during the procedure.
8. Locate the radial pulse (Figure 2). Inﬂate the
BP cuff by pumping the cuff bulb, until the
radial pulse can no longer be felt. Note the
reading on the dial. This ﬁgure is the estimated
9. Deﬂate the BP cuff completely and wait for
NURSING STANDARD january 20 :: vol 30 no 21 :: 2015 37
10. Palpate the brachial artery to ensure the correct
placement of the stethoscope. Place the centre
of the stethoscope bell over the brachial artery
11. Inﬂate the cuff again to 20-30mmHg above the
predicted systolic BP.
12. Deﬂate the cuff slowly at a rate of 2mmHg
at a time [Q Please provide reference, others
state that this should be per pulsation] listening
for Korotkoff sounds – often described as
whooshing, pounding, swishing or thudding
sounds. As you deﬂate the cuff, note when the
loud thudding occurs; this is the systolic BP.
These sounds will gradually change and become
mufﬂed, eventually disappearing. At this point,
record the number on the sphygmomanometer;
this is the diastolic BP. In some patients
with hypertension, there may be a notable
auscultatory gap in the sounds, this is a period of
diminished or absent Korotkoff sounds during
the measurement, and should be reported.
13. Once no further sounds can be heard, deﬂate the
cuff fully and remove it from the patient’s arm.
14. If you need to recheck the patient’s blood
pressure, wait one to two minutes before
15. Inform the patient that the procedure is ﬁnished.
16. Wash your hands using bactericidal soap and
water or bactericidal alcohol handrub.
17. Clean the bell and diaphragm of the
stethoscope and the cuff with a detergent wipe.
18. Record the BP reading clearly on the observation
sheet or early warning score chart. Compare
the measurement with previous results. Inform
medical staff if there are signiﬁcant changes or
if this is required in accordance with the early
warning scoring system.
19. It is also important to calculate and document
the mean arterial pressure using the formula
in Box 1. The mean arterial pressure is the
amount of pressure required by the body to
ensure that all organs receive an adequate blood
supply (Marieb 2013). The normal range is
Correct position of the cu
SCIENCE PHOTO LIBRARY
Blood pressure cu sizes
Indication Bladder width
and length (cm)
Small adult/child 12x18 <23
Standard adult 12x26 <33
Large adult 12x40 <50
(British Hypertension Society 2009)
38 january 20 :: vol 30 no 21 :: 2015 NURSING STANDARD
Art & science clinical skills
BP recording is essential to establish baseline
measurements, which can provide vital
information about a patient’s health and are
central to the diagnosis and monitoring of a wide
range of conditions.
In the past, staff may have relied on automated
BP measuring devices. However, the use of these
devices can be problematic, because of inaccurate
readings and shortages of appropriate equipment
(Alexis 2009). The accuracy and reliability of
these devices has been questioned, particularly
in patients with cardiac arrhythmias (Cork
2007). The Medicines and Healthcare products
Regulatory Agency (MHRA) (2013) refers to
manual BP measurement as the ‘gold standard’.
It raises concerns about an over-reliance on
electronic devices and the de-skilling of healthcare
professionals in manual techniques. The British
Hypertension Society (2009) does not make
recommendations regarding manual or electronic
measurement of BP, however it emphasises the
importance of using the appropriate cuff size to
ensure an accurate BP reading.
In some clinical areas, for example critical
care, arterial lines are used for more accurate
and constant measurement of BP in critically ill
patients. However, it is important that all nurses
are skilled in performing manual BP measurement.
Heinemann et al (2008) found that automated
BP measurement devices can be used with some
conﬁdence to record systolic BP in most adults, but
there was some variation observed when recording
The accuracy of BP measurement is
determined [Q ensured?] by the use of
appropriate equipment that is in good working
order, and consideration of factors related to
the patient and environment that may affect
BP readings. This includes selecting the correct
sized cuff (British Hypertension Society 2009),
ensuring the bladder tubing does not have any
cracks or faults (Smith and Roberts 2011), and
ensuring the correct positioning and preparation
of the patient; they should be rested to avoid
anxiety. It is also important to acknowledge that
patient factors such as age, weight and diet can
also affect BP.
[Q hypo or hyper in this para? or both,
as it is now?] If postural hypertension is
suspected, the patient may require a sitting and
standing BP (Wallymahmed 2008). Postural
hypotension is deﬁned as a drop in BP of
>20/10mmHg. The prevalence of postural
hypertension increases with age because the
baroreﬂex mechanisms that control heart rate
and vascular resistance decline with age.
Other causes of hypotension include long-term
neurological conditions such as Parkinson’s
disease and drugs that affect reﬂex control,
such as antidepressants and alcohol.
The Nursing and Midwifery Council (2010)
identiﬁed the measurement of BP as an essential
skill that all nurses must be able to undertake,
both manually and using electronic devices.
More recently, there has been an increase
in the measurement of BP using a manual
sphygmomanometer, with some trusts observing
a reduction in the number of deteriorating patients
and cases of unexpected cardiac arrest as a result
of increased awareness of the signs of patient
deterioration (Snow 2011).
It is acknowledged that automated BP
monitoring equipment should not be used on
patients with a high or low BP, since diastolic BP
measurements have been found to be incorrect and
unreliable (Heinemann et al 2008). Automated
Calculating the mean arterial pressure
Mean arterial pressure = Systolic BP +
(2 x Diastolic BP)/3
Position of the stethoscope over the brachial artery
SCIENCE PHOTO LIBRARY
NURSING STANDARD january 20 :: vol 30 no 21 :: 2015 39
devices are also not suitable for patients with
abnormal heart rhythms or weak pulses (Cork
2007, MHRA 2013). Fallon (2015) discussed the
inaccuracies of BP recordings for patients with
atrial ﬁbrillation or an irregular heart rhythm
and the difﬁculty in determining a deﬁnite end
point for diastolic BP, since automated devices
have not been validated for use in patients with
Manual BP measurement is an essential nursing
skill and nurses should regularly undertake this
activity to ensure they are competent to perform
the procedure and take accurate readings.
Whichever device is used for measuring BP, it
must be properly validated, regularly maintained
and recalibrated according to the manufacturer’s
instructions (Fallon 2015) NS
Disclaimer: please note that information provided by N ursing
Standard is n ot suﬃcient to make the reader com petent to
perform the task. All clinical skills should be formally assessed
at the bedside by a nurse educato r or mentor. It is the nurse’s
responsibility to ensure their practice remains up to date and
reﬂects the latest evidence.
Alexis O (2009) Providin g best
practice in manual blood pr essure
measurement. British Journal of
Nursing. 18, 7, 410-41 5.
British Hypertension Society (20 09)
Blood Pressure Measurement: With
Manual Blood Pressure Monito rs.
tinyurl.com/nrlqdl2 (Last accessed:
December 17 2015.)
Cork A (2007) Theory and
practice of manual blood pressure
measurement. Nursing Standard.
22, 14-16, 47-50.
Fallon N (2015) T he challe nge of
measuring blood pressure accurately.
British Jou rnal of Cardiac Nursing.
10, 3, 132.
Heinema nn M, Sellick K, Rickard C,
Reynolds P, McGrail M (2008)
Automated versus manual
blood pressure measurement:
a randomized crossover trial.
International Journal of Nursing
Practice. 14, 4, 296 -302.
Marieb EN (2013) Essentials
of Human Anatomy and
Physiology. Tenth edition. Pearson
Medicines and Healthcare products
Regulatory Agency (2013) Blood
Pressure Measurement Devices.
accessed: December 17 2015.)
Nursing and Midwifery
Council (2010) Standards for
Pre-Registration Nursing and
Education. Annexe 3: Es sential
Skills Clusters and Guidance
for their Use. tinyurl.com/
oqel3jq (Last accessed:
December 17 2015.)
Smith J, Rob erts R (2011) Vital
Signs for Nurses: An Introductio n
to Clinical Observations.
Snow T (2011) Manual checks for
deterioration helps trust cut cardiac
arrest. Nursing Standard. 25, 42, 10.
Wallymahmed M (2008) Blood
pressure measurement. Nursing
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Dougherty L, Lister S (2011) The Royal Marsden
Hospital Manual of Clinical Nursing Procedures.
Eighth edition. Wiley-Blackwell, Chichester.
National Institute for Health and Care Excellence
(2011) Hypertension in Adults: Diagnosis and
Management. Clinical Guideline No. 127. NICE, London.
Stergiou GS, Kollias A, Destounis A, Tzamouranis D
(2012) Automated blood pressure measurement
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