ASSESSMENT: BLOOD PRESSURE MEASUREMENT

PURPOSE Non-invasive blood pressure (BP) measurement is an essential component of pediatric physical assessment. Correct technique for measuring BP is necessary to ensure accuracy of readings, while ensuring minimal discomfort to the patient. GUIDELINE Non-Invasive Blood Pressure is generally measured using auscultatory (sphygmomanometer, manual) or oscillometric (electronic) methods. Oscillometric devices are useful in situations in which auscultation is difficult, such as in infants and where frequent BP measurements are necessary. The oscillometric method is the method used for most patients at BCCH. However, due to possible inaccuracies in oscillometric readings, any abnormal reading or significant change in reading should be validated by the auscultation method. For patients with thrombocytopenia or other coagulopathies or on anticoagulation therapy, an ausculatory BP measurement should be considered due to increased risk of bleeding with an automated BP monitor. First choice for blood pressure measurement is the arm. Leg BPs are only done if an arm is not an option or if specifically ordered. Readings are not interchangeable. SITE APPLICABILITY Applicable in all clinical areas. PRACTICE LEVEL/COMPETENCIES Blood pressure measurement is a foundational nursing competency. DEFINITIONS Auscultatory: Manual BP measurement using sphygmomanometer and stethoscope. In sphygomomanometry, the pressure necessary to collapse the artery in the arm or leg is determined with inflation of the cuff. As the cuff is deflated, the pressure is noted as sounds produced by the arterial pulse waves (Korotkoff’s sounds) that appear and disappear again as flow through the artery resumes. Korotkoff’s sounds: K1: first appearance of clear, repetitive, tapping sounds = systolic BP K2: sounds are softer and longer, with the quality of an intermittent murmur K3: sounds become crisper and louder K4: sounds are muffled, less distinct and softer K5: sounds disappear = diastolic BP Oscillometric: Automated device that uses oscillometric methods for measurement of BP, with detection of oscillations on the walls of the occluded artery as the cuff is deflated. Systolic and mean BP values are measured, but diastolic BP is a derived value and therefore may not be accurate.

Brachial Artery: is the major blood vessel of the upper arm located by palpating around the atecubetal fossa.

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Dorsalis Pedis Artery: is a blood vessel in the lower limbs palpated on the dorsal surface of the foot.

Posterior tibial artery: is a blood vessel in the lower limbs readily palpated posterior and inferior to the ankle bone.

Popliteal artery: is a blood vessel in the lower limbs palpated behind a semi-flexed knee.

Orthostatic/postural hypotension: is a form of low blood pressure that happens when you stand up from sitting or lying down. It can make you feel dizzy or lightheaded, and maybe even faint. Orthostatic hypotension is a drop of at least 20 mmHg systolic or 10 mmHg diastolic in blood pressure when someone stands quietly for about 3 minutes after rising from a sitting or lying position. To assess for presence of orthostatic or postural hypotension: 1. patient to be supine for 5-10 minutes 2. have patient sit on side of bed for 2-3 minutes 3. Assist patient to standing position. Wait 2-3 minutes and measure BP. EQUIPMENT

o For Oscillometric (automatic BP monitor) measurement: . Blood pressure monitor . Blood pressure cuff of appropriate size . Pillow to stabilize arm, if necessary

o For Ausculatory (manual BP) measurement: . Stethoscope . Sphygmomanometer . Blood pressure cuff of appropriate size . Pillow to stabilize arm, if necessary

PROCEDURE Rationale 1. DETERMINE frequency of measuring Blood Blood Pressure values are a basis for major Pressure (BP) based on: diagnostic and therapeutic decisions and BP a. Unit standard evaluation is included as part of a complete physical b. Prescriber’s order assessment. c. Nurse’s clinical judgment d. Nursing Care Plan e. As required for a particular procedure or medication 2. PERFORM hand hygiene. Routine infection control practices; reduces

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transmission of microorganisms. 3. IDENTIFY patient and PREPARE patient for BP Ensures identification mechanism is present to measurement. prevent treatments, medications, and procedures to wrong child. Anxiety may be reduced by a simple explanation of the procedure, such as how the cuff will feel, e.g. tightening, hugging the arm. Environmental factors, such as room temperature, light levels, room noise and other occupants may influence BP. Ensure external factors are reduced as much as possible 4. DETERMINE which site will be used to measure BP: The arm is the site of choice for BP measurement. • Arm The right arm is preferred in children because: • Calf • Standardized BP tables reflect right arm • Thigh readings • False low readings are obtained in the left arm NOTE: for all patients with coarctation of the aorta or of children with coarctation of the aorta hypoplastic left heart, confirm with the cardiologist if it is necessary to obtain a 4 limb BP once daily. The calf BP In some cases, BP may vary up to 10 mmHg measurement is often used when coarctation of the between dominant and non-dominant arms aorta is suspected. Taking BP on an arm with compromised peripheral circulation, intra-arterial catheters, intravenous catheters, arteriovenous fistulas, BT shunts or peripherally inserted central catheters should be avoided. Leg and arm BP measurements are not interchangeable. Oscillometric thigh BPs are the most uncomfortable for children and the American Association of Critical Care Nurses' Protocols for Practice (2006), recommend that the thigh not be used for BP measurement. 5. SELECT appropriate sized cuff. If a cuff is too small, Selection of the proper-sized cuff is considered one of the next largest cuff should be used, even if it the most important factors when measuring BP. appears large. A too small cuff will give significantly higher readings; a too large cuff will give significantly lower readings. Recommended Dimensions for BP Cuff Bladders Age Range Max arm Bladder Bladder circumference Width Length (cm)* Newborn 10 4 8 Infant 15 6 12 Child 22 9 18 Small Adult 26 10 24 Adult 34 13 30 Large Adult 44 16 38 * Calculated so that the largest arm would still allow the bladder to encircle arm by at least 80%.

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NOTE: The cuff should cover at least two thirds of the limb section (i.e. upper arm, calf, thigh) and the bladder should encircle 80% to 100% of the circumference of the limb as shown:

6. POSITION patient in desired position. (i.e. lying, Diastolic pressure is slightly higher when sitting than sitting, and standing). lying and systolic pressure is slightly higher when lying than sitting. Lying and standing BPs may be ordered in patients with suspected orthostatic/postural hypotension. 7. LOCATE the brachial artery by palpation. Ensure the cuff is not wrapped too tightly as it may cause venous congestion. Proper cuff application NOTE: if using the calf, locate the dorsalis pedis or improves accuracy of measurement. posterior tibial artery. If using the thigh, locate the popliteal artery found just behind the knee. 8. APPLY cuff. SQUEEZE air from the cuff, and wrap it smoothly and snugly around the limb. Arm: position the middle of the bladder, indicated by the manufacturer’s marker, over the palpated brachial artery, 2-3 cm above the antecubital fossa. Calf: position the middle of the bladder, indicated by the manufacturer’s marker, over the palpated artery, approximately 2.5 cm above the inner ankle bone. Thigh: apply the cuff just above the knee with the bladder over the popliteal artery. 9. For arm BP measurement, POSITION the arm so Arm position can have a major influence on BP. If the that the antecubital fossa (ACF) is at heart level. upper arm is below the right atrium, the readings will Support the arm throughout measurement. If patient be too high. If the arm is above the right atrium, the is lying down, support the arm with a pillow so that readings will be too low. the ACF is at heart level. For calf BP measurements, PLACE patient supine. For thigh BP measurement, PLACE patient prone. If the patient cannot be placed in the prone position, position the patient supine with knee slightly bent. 10. For Oscillometric (automatic BP monitor) Correctly functioning device ensures accurate measurement: readings;

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a. Ensure device is functioning correctly Selecting the correct mode prevents unnecessarily b. Connect cuff to BP monitor tubing high inflation of the cuff that causes excessive c. Ensure tubing is free of kinks discomfort to child. d. Select the correct patient mode (adult, pediatric, neonate) if required e. Stabilize limb as movement causes artifact f. Press start to obtain reading g. Set and activate appropriate alarms if device to be used for ongoing monitoring. 11. For Ausculatory (manual BP) measurement: Over inflation of the cuff should be avoided because a. Place stethoscope over palpated artery of discomfort. It is useful to initially inflate the cuff b. Palpate the radial pulse and inflate cuff to while palpating the pulse to estimate the approximate 20-30 mmHg above the point where radial range for the systolic pressure and then inflate the pulse disappears. cuff to 30 mmHg above this estimate when the BP is c. Partially open valve and deflate the bladder auscultated. at 2-3 mm/sec while listening for Korotkoff The first Korotkoff sound (K1) corresponds to the sounds onset of clear tapping=systolic pressure. The fifth d. As pressure in cuff decreases, note the Korotkoff (K5) sound corresponds to diastolic reading on the sphygmomanometer for first pressure and is considered the disappearance of any appearance of tapping (systolic reading) to sounds. In children, the sound often remains to 0 when tapping sounds muffle and disappear mmHg. In this situation, the fourth Korotkoff sound (diastolic reading). (K4), indicated by muffling of sound, and is considered the diastolic pressure.

12. REMOVE BP cuff unless frequent monitoring (every Oscillometric monitors recalibrate each time they are 5-15 minutes) or repeat reading is required. Leave turned on. For accurate measurements, it is best to oscillometric monitor on if on frequent monitoring or leave monitor on between readings. for repeat readings. 13. NOTIFY physician or health care team in the case of Communication of abnormal BP measurement to unexpected or abnormal readings. additional members of the health care team.

14. CLEAN equipment after use. If equipment is being Reduces infection rates between patients. shared between patients it is the nurse’s See Non-critical equipment Cleaning Policy responsibility to wipe off the machine after use. Use required cleaning wipes.

DOCUMENTATION

RECORD BP measurement on patient care flowsheet and other documents as appropriate indicating: a. Date and time CC.03.02 BC Children’s Hospital Child & Youth Health Policy and Procedure Manual Effective Date: Feb-01-2017 Page 5 of 6 ASSESSMENT: BLOOD PRESSURE MEASUREMENT

b. Systolic/diastolic readings c. Limb used (if other than arm)

d. Patient position using the following symbols lying sitting standing e. Patient’s response if unusual f. Any other pertinent actions or observations

REFERENCES Frese, E.M., Fick, A. and Sadowsky, H.S. (2011). Blood Pressure Measurement Guidelines for Physical Therapists. Cardiopulmonary Physical Therapy Journal, 22(2):5-12. Martin, B. (2010). American Association of Critical Care Nurses Practice Alert: Non-Invasive Blood Pressure Monitoring. Ogedegbe, G. and Pickering, T.G. (2010). Principles and Techniques of Blood Pressure Measurement. Cardiology Clinics, 28(4): 571–586. Park, M.K., Menard, S.W. and Yuan, C. (2001). Comparison of Ausculatory and Oscillometric Blood Pressures. Archives of Pediatric and Adolescent Medicine, 55(1):50-53. Pickering, T.G., Hall, J.E., Appel, L.J., Falkner, B.E., Graves, J., Hill, M.N., Jones, D.W., Kurtz, T., Sheps, S.G. and Roccella, E.J. (2005). Recommendations for Blood Pressure Measurement in Humans and Experimental Animals: Part 1: Blood Pressure Measurement in Humans: A Statement for Professionals from the Subcommittee of Professional and Public Education of the American Heart Association Council on High Blood Pressure Research. Hypertension, 45(2):142-161. Retrieved May 31, 2013 from http://hyper.ahajournals.org/cgi/reprint/45/2/299 Schell, K.A. (2006). Evidence-Based Practice: Noninvasive Blood Pressure Measurement in Children. Pediatric Nursing, 32(3):263-267. Schell, K., Briening, E., Lebet, R., Pruden, K., Rawheiser, S. and Jackson, B. (2011). Comparison of Arm and Calf Automatic Noninvasive Blood Pressures in Pediatric Intensive Care Patients. Journal of Pediatric Nursing, 26(1):3-12. Torzone, A. (2008). Heart Rate and Blood Pressure: Obtaining an Accurate Measurement. In Trivits Verger, J. and Lebet, R.M. (ed). American Association of Critical Care Nurses Procedure Manual for Pediatric Acute and Critical Care. Saunders Elsevier, St Louis, Missouri. US Department of Health and Human Services. (2005). The Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents. National Institute of Health, National Heart, Lung, and Blood Institute. Retrieved May 31, 2013 from http://www.nhlbi.nih.gov/health/prof/heart/hbp/hbp_ped.htm Valler-Jones, T. and Wedgbury, K. (2005). Measuring Blood Pressure using the Mercury Sphygmomanometer. British Journal of Nursing, 14(3):145-150.

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