noninvasive blood pressure monitoring issued april 2010

Noninvasive Blood Pressure Noninvasive Blood Pressure MonitoringMonitoring

Issued April 2010Issued April 2010

Noninvasive Blood Pressure Monitoring2

Expected Practice

Measure blood pressure (BP) in the upper arm using the oscillatory or auscultatory method.

Unable to measure in the upper armMeasure in forearmConsider thigh or calf measurement

Expected Practice

Use appropriate size BP cuff



Expected Practice

Measure baseline BP bilaterally


Expected Practice

Position patient the appropriate reference level for NIBP is

the heart.


Patient Position—Seated Patient should be seated with back and arms supported,

feet on floor, and legs uncrossed with upper arm at heart level (phlebostatic axis: 4th intercostal space, halfway between the anterior and posterior diameter of the chest) (Figure 1)

Figure 1


Patient Position—Supine position patient supine

or

with head of bed at a comfortable level and with upper arm supported at heart level.

Figure 2

Figure 3


Expected Practice

The patient and the caregiver should remain quiet throughout the procedure of taking a BP


Scope and Impact of the Problem

Blood pressure is measured in virtually all patients

Accurate measurement of blood pressure is essential to guide management decisions

Inaccuracy may lead to over or under-treatment of the patient’s condition


Supporting Evidence

Use oscillatory devices that meet the Association for the Advancement of Medical Instrumentation standards (mean difference + 5mm Hg and standard deviation < 8mm Hg) when compared to auscultatory method12 and the appropriate size cuff.


Supporting Evidence Stiffness of the arteries, influences amplitude of the oscillations

and may cause underestimation MAP

Accuracy of the automated device may also be limited in patients with hypertension, hypotension, and cardiac dysrhythmia.

Some studies showed difference < 5mm Hg between BP measurement methods, other studies demonstrated that individual differences may be > 10mm Hg for some individuals.

Vasopressors show no significant effect on difference


Supporting Evidence

Forearm and upper arm BP's are not interchangeable

Select the proper cuff size and positioning of forearm at heart level


Supporting Evidence

Cuff Position

Forearm – position the cuff midway between the elbow and wrist

Thigh – position the cuff over the lower third of thigh ( lower edge of cuff approximately 2 to 3cm above popliteal fossa)


Supporting Evidence

With all BP measurements select the proper size cuff

Calf BP measurements- place the patient in the supine position. Place the patient in the prone position for thigh BP measurements. If the patient cannot be place prone, position the patient supine with knee slightly bent.

Thigh pressures are normally higher than upper arm pressures

Calf pressures are not interchangeable with upper arm pressures


Supporting Evidence

Calf BP measurement (referred to as an ankle BP) Korotkoff’s sounds are auscultated over either the dorsalis pedis or posterior tibial artery in calf BP or the popliteal artery in thigh BP

In adults, calf BP's should be used only if the upper arm is not accessible


Supporting Evidence Reasons an extremity may not be suitable for BP

measurement.

BP cuffs should not be used on extremities with a deep vein thrombosis, grafts, ischemic changes, arteriovenous fistula, or arteriovenous graft

BP cuffs should not be applied over a PICC or midline catheter site

In extremities with peripheral IV while an infusion is running or any trauma/incision.

Patients that have had mastectomy or lumpectomy do not use the involved arm(s) for BP's if there is lymphedema.


Supporting Evidence

Appropriate cuff size necessary for accurate measurement of BP in all extremitiesCuff too narrow = overestimation of BPCuff too wide = underestimation BP. Cuff is too small = falsely high reading may result Cuff is too large = falsely low reading may resultUse a cuff with a bladder capable of going around

80% of the arm


Supporting Evidence Patients with aortic dissection, congenital heart disease,

coarctation of the aorta, peripheral vascular disease, and unilateral neurological and musculoskeletal abnormalities may demonstrate a difference in inter-arm BP

20% - 40% of individuals without the above conditions may have a measurable difference of 10 to 20mm Hg BP between left and right arms

One study showed higher mean differences in systolic and diastolic BP in older participants

When there is a consistent interarm difference, use the arm with higher pressure.


Supporting Evidence

Body position and arm position influence the measurement of BP

With patient supine and arm placed at heart level the systolic BP is approximately 8mm Hg higher than in the sitting position

Studies show if arm is below heart level BP readings will be higher, conversely, if the arm is above heart level BP readings will be lower


Supporting Evidence

Systolic and diastolic BP's in hypertensive and normotensive patients increase with talking


Actions for Nursing Practice

Ensure that your facility has written procedures BP measurement

Ensure proper size cuffs are readily available

Ensure devices meet appropriate standards

Provide routine training healthcare providers in BP measurement


For more information or further assistance, please contact a clinical practice specialist with the AACN Practice Resource Network.

Need More Information?

Email:[email protected]


noninvasive blood pressure monitoring issued april 2010

Documents

problem blood pressure

calf measurement slide

upper arm measure

prone position

appropriate size cuff

thigh bp measurements

upper arm pressures

proper cuff size