AACN News Logo

Back to AACN News Home

Vol. 23, No. 6, JUNE 2006


Practice Alert:

The goal of the AACN Practice Alerts is to help nurses and other healthcare practitioners carry their bold voices to the bedside to directly impact patient care. Practice Alerts are directives from AACN that are supported by authoritative evidence to ensure excellence in practice and a safe and humane work environment.

Expected Practice:
-- Measure blood pressure (BP) in the upper arm using the oscillatory or auscultatory method.
• If upper arms cannot be used for BP measurement or if the maximum size BP cuff does not fit the upper arm, blood pressure may be measured in the forearm.
• Consider use of thigh and calf for BP measurement if the upper arms and forearms cannot be used.
-- Use appropriate size BP cuff and follow instructions for fit and placement per manufacturer’s recommendations.
-- Measure baseline BP in both upper arms. For significant differences in BP, use the arm with the higher pressure.
-- Position patient:
• 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)
• If patient cannot be seated, position patient supine (Figure 2) or with head of bed at a comfortable level (Figure 3) and with upper arm supported at heart level.
-- The patient and the caregiver should remain quiet throughout the procedure of taking a BP.

Supporting Evidence:
• Studies comparing oscillatory BPs to intra-arterial1,2 and/or auscultatory BPs3-11 were reviewed. Each manufacturer of automatic oscillatory devices has its own algorithm for deriving systolic and diastolic from the detected mean arterial pressure; readings from one device may differ from another. Thus, comparison between studies is difficult if different oscillometric devices and data collection procedures are used. To promote accuracy, nurses should use oscillatory devices that meet the Association for the Advancement of Medical Instrumentation standards (mean difference ± 5 mm Hg and standard deviation ≤ 8 mm Hg) when compared to auscultatory method12 and the appropriate size cuff.

• Stiffness of the arteries, particularly in older patients, also influences amplitude of the oscillations and may cause underestimation of mean arterial pressure.3,10 Accuracy of the automated device may also be limited if patients are hypertensive,3 hypotensive,5 and/or have cardiac dysrhythmia.13 While some studies showed differences < 5 mm Hg between BP measurement methods, other studies demonstrated that individual differences may be > 10 mm Hg for some individuals. Vasopressors have shown no significant effects on differences.5,8 (Level IV)

• Research has shown that the forearm and upper arm BPs are not interchangeable. If the forearm is used, selection of the proper cuff size and positioning of forearm at heart level are necessary.13-17 (Level VI)

• If using the forearm, position the cuff midway between the elbow and the wrist. If using the calf, position the lower edge of the cuff approximately 2.5 cm above the malleoli. If using the thigh, position the cuff over the lower third of the thigh so that the lower edge of the cuff is approximately 2 to 3 cm above the popliteal fossa.18,19 (Level II)
• If the thigh or calf is used for BP measurement, the same attention to selection of proper cuff size is necessary. For calf BP measurements, place the patient in the supine position.18 Place the patient in the prone position for thigh BP measurements. If the patient cannot be placed prone, position the patient supine with knee slightly bent.19 Normally, thigh pressures are higher than upper arm pressures though no research was found to substantiate this.19 (Level II) Research has demonstrated that calf pressures are not interchangeable with upper arm pressures.20,21 (Level IV)
• Calf BP measurement is also referred to as an ankle BP. If a stethoscope is used, Korotkoff’s sounds are auscultated over either the dorsalis pedis or posterior tibial artery (for calf BP) or the popliteal artery (for thigh BP). Results of comparisons of automatic, noninvasive upper arm and calf BPs in adults vary. Overall, systolic BP measurements were higher in the calf than the arm in patients undergoing surgery, colonoscopy, and caesarean delivery under spinal anesthesia.20-22 (Level V) Differences in mean BP and diastolic BP were not consistent. Large differences for some individuals make it difficult to devise a predictive formula that would be applicable in all situations.21 In adults, calf BPs should be used only if the upper arm is not accessible20 or if the appropriate size cuff is not available.
• Multiple reasons exist why an extremity may not be suitable for BP measurement. BP cuffs should not be used on an extremity with a deep vein thrombosis, grafts, ischemic changes, arteriovenous fistula, or arteriovenous graft.23-25 BP cuffs should not be applied over a peripherally inserted central catheter (PICC) or midline catheter site but may be placed distally to the insertion site.23 BP measurements should not be taken in extremities with peripheral IV while an infusion is running 26 or any trauma/incision. For patients who have had a mastectomy or lumpectomy, do not use the involved arm(s) for BPs if there is lymphedema.13,27 (Level II)
• Wrap cuff snugly around upper arm so that the end of the cuff is 2 to 3 cm above the antecubital fossa to allow room for placement of the stethoscope for manual B/P measurement.13 Align the cuff to ensure the mark on the cuff for artery is placed over the artery.
• Selection of a BP cuff of the appropriate size is necessary for accurate measurement of BP. Studies have shown that the use of a cuff that is too narrow results in an overestimation of BP, and a cuff that is too wide underestimates BP. A falsely high pressure reading may result when the cuff is too small relative to the patient arm circumference. If the cuff is too large, falsely low pressure readings can result. A cuff with a bladder of an adequate size capable of going around 80% of the arm is recommended.13,23,28-30 If the thigh or calf is used, the same attention to selection of proper cuff size is necessary. (Level VI)
• 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.31 Additionally, research has shown that up to 20% to 40% of individuals without the above conditions may also have measurable differences of 10 to 20 mm Hg in systolic and diastolic BP between the left and right arms.32-36 Research methodology included oscillatory or auscultatory BP measurements with both methods demonstrating similar findings. Age was a factor in one study with higher mean differences in both systolic BP and diastolic BP in older participants.32 (Level V)
• Body position and arm position influence the measurement of BP.13,37,38 With the arm placed at heart level and the patient supine, the systolic BP readings are approximately 8 mm Hg higher than in the sitting position.13,39,40 Studies also show that if the arm is below the level of the right atrium or heart level, the BP readings will be higher. Conversely, if the arm is above heart level, the BP readings will be lower. This average BP difference of up to 10 mm Hg when the arm is not at heart level is attributed to the effects of hydrostatic pressure.13,39,40 (Level VI)
• Systolic and diastolic BPs of hypertensive and normotensive patients increase with talking.13,41-43 (Level V)

What You Should Do:
• Ensure that your units have a written practice document such as policy, procedure, or standard of care for BP measurement that includes documentation of site and inter-arm differences.
• Ensure proper size cuffs are readily available.
• Provide routine training and retraining of healthcare providers in BP measurement and equipment use.

AACN Grading Level of Evidence
Level I: Manufacturer’s recommendations only
Level II: Theory based, no research data to support recommendations; recommendations from expert consensus group may exist
Level III: Laboratory data, no clinical data to support recommendations
Level IV: Limited clinical studies to support recommendations
Level V: Clinical studies in more than 1 or 2 patient populations and situations to support recommendations
Level VI: Clinical studies in a variety of patient populations and situations to support recommendations


References
1. Bur A, Hirschl M, Herkner H, et al. Accuracy of oscillometric blood pressure measurement according to the relation between cuff size and upper-arm circumference in critically ill patients. Crit Care Med. 2000;28:371-376.
2. Bur A, Herknew H, Vicek M, et al. Factors influencing the accuracy of oscillometric blood pressure measurement in critically ill patients. Crit Care Med. 2003;31:793-799.
3. Braam RL, Thien T. Is the accuracy of blood pressure measuring devices underestimated at increasing blood pressure levels? Blood Press Monit. 2005;10:283-289.
4. Chang JJ, Rabinowitz D, Shea S. Sources of variability in blood pressure measurement using the Dinamap PRO 100 automated oscillometric device [abstract]. Am J Epidemiology. 2003;158:1218-1226.
5. Davis J, Davis I, Bennink LD, et al. Are automatic blood pressure measurements accurate in trauma patients? J Trauma. 2003;55:860-863.
6. Parker SB, Steigerwalt SP. The Dinamap dilemma: inaccuracy of the commonly used Dinamap 8100 compared to simultaneous mercury manometer measurement in hospitalized patients at different levels of blood pressure [abstract]. Am J Hypertens. 2004;17(suppl 1):S52.
7. Shahriari M, Rotenberg DK, Nielsen JK, et al. Measurement of arm blood pressure using different oscillometry manometers compared to auscultatory readings [abstract]. Blood Press. 2003;12:155-159.
8. Terra SG, Blum RA, Wei G, et al. Concordance and variability of blood pressure measurement between automated and manual readings in subjects receiving phenylephrine [abstract]. Clin Pharmacol Ther. 2003;73:P71.
9. Van Ittersum FJ, Wijering RM, Lambert J, et al. Determinants of the limits of agreement between the sphygmomanometer and the SpaceLabs 90297 device for blood pressure measurement in healthy volunteers and insulin-dependent diabetic patients. J Hypertens. 1998;16:1125-1130.
10. van Montfrans GA. Oscillometric blood pressure measurement: progress and problems. Blood Press Monit. 2001;6:287–290.
11. van Popele NM, Bos WJ, de Beer NAM, et al. Arterial stiffness as underlying mechanism of disagreement between an oscillometric blood pressure monitor and a sphygmomanometer. Hypertension. 2000;36:484-488.
12. White WB, Berson AS, Robbins C, et al. National standard for measurement of resting and ambulatory blood pressures with automated sphygmomanometers. Hypertension. 1993;21:504-509.
13. Pickering TG, Hall JE, Appel LJ, et al. 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. 2005;45:142-161.
14. Palatini P, Longo D, Toffanin G, et al. Wrist blood pressure overestimates blood pressure measured at the upper arm. Blood Press Monit. 2004;9:77-81.
15. Pierin AM, Alavarce DC, Gusmao JL, et al. Blood pressure measurement in obese patients: comparison between upper arm and forearm measurements. Blood Pres Monit. 2004;9:101-105.
16. Schell K, Bradley E, Bucher L, et al. A clinical comparison of forearm and upper arm automatic, noninvasive blood pressures. Am J Crit Care. 2005;14:232-241.
17. Schell K, Lyons D, Bradley E, et al. Clinical comparison of automatic, noninvasive measurements of blood pressure in the forearm and upper arm with the patient supine or with the head of the bed raised 45 degrees: a follow-up study. Am J Crit Care. 2006;15:196-205.
18. Perry, AG, Potter, PA. Clinical Nursing Skills and Techniques, 5th ed. St Louis, Mo: Mosby. 2004;240-249.
19. Jarvis C. Physical Examination and Health Assessment, 4th ed. St Louis, Mo: Elsevier; 2004:189.
20. Wilkes JM, DiPalma JA. Brachial blood pressure monitoring versus ankle monitoring during colonoscopy. South Med J. 2004;97:939-941.
21. Zahn J, Bernstein H, Hossain S, et al. Comparison of noninvasive blood pressure measurements on the arm and calf during Cesarean delivery. J Clin Monit Comput. 2000;16:557-562.
22. Block FE, Schulte GT. Ankle blood pressure measurement, an acceptable alternative to arm measurements. Int J Clin Monit Comput. 1996;13:167-171.
23. Giuliano K. Noninvasive blood pressure monitoring. In: Burns SM, ed. AACN Protocols for Practice: Noninvasive Monitoring, 2nd ed. Sudbury, Mass: Jones and Bartlett Publishers; 2005:83-97.
24. Intravenous Nurses Society. Arteriovenous fistulas and hemodialysis catheters. J Inf Nurs. 2006;29:S46-S47.
25. National Kidney Foundation/Dialysis Outcomes Quality Initiative. Clinical practice guidelines for vascular access. Am J Kidney Dis. 2001;37:S137-S181.
26. Intravenous Nurses Society. Standards: site selection and device placement. J Inf Nurs. 2006;29:S37-S39.
27. American Cancer Society. Lymphedema: What every woman with breast cancer should know. Available at: http://www.cancer.org/docroot/CRI/content/CRI_2_6X_Lymphedema_5.asp. Accessed February 12, 2006.
28. Fonseca-Reyes S, Garcia de Alba-Garcia J, Parra-Carrillo JZ, et al. Effect of standard cuff on blood pressure readings in patients with obese arms. How frequent are arms of a ‘large circumference’? Blood Press Monit. 2003; 8:101-106.
29. Maxwell MH, Waks AU, Schroth PC, et al. Error in blood-pressure measurement due to incorrect cuff size in obese patients. Lancet. 1982;2:33-36.
30. Sprafka JM, Strickland D, Gomez-Marin O, et al. The effect of cuff size on blood pressure measurement in adults. Epidemilogy. 1991;2:214-217.
31. Peroff D, Grim C, Flack J, et al. Human blood pressure determination by sphygmomanometry. Circulation. 1993;88:2460-2470.
32. Lane D, Beevers M, Barnes N, et al. Inter-arm differences in blood pressure: when are they clinically significant? J Hypertens. 2002;20:1089-1095.
33. Singer AJ, Hollander JE. Blood pressure, assessment of interarm differences. Arch Intern Med. 1996;56: 2005-2008.
34. Fotherby MD, Panaylotou B, Potter JF. Age-related differences in simultaneous interarm blood pressure measurements. Postgraduate Med J. 1993;69:194-196.
35. Orme S, Ralph SG, Birchall A, et al. The normal range for inter-arm differences in blood pressure. Age Ageing. 1999;28:537-542.
36. Cassidy P, Jones K. A study of inter-arm blood pressure differences in primary care. J Hypertens. 2001;5: 519-522.
37. Peters GL, Binder SK, Campbell NR. The effects of crossing legs on blood pressure: a randomized single-blind cross-over study. Blood Press Monit. 1999;4:97-101.
38. Keele-Smith R, Price-Daniel C. Effects of crossing legs on blood pressure measurement. Clin Nurs Res. 2001;10:202-213.
39. Netea RT, Elving LD, Lutterman JA, et al. Body position and blood pressure measurement in patients with diabetes mellitus. J Int Med. 2002;251:393-399.
40. Netea RT, Lenders JM, Smits P, et al. Influence of body and arm position on blood pressure readings: an overview. J Hypertension. 2003;21:237-241.
41. Pailleru CL, Helft G, Landais P, et al. The effects of talking, reading, and silence on the “white coat”phenomenon in hypertensive patients. Am J Hypertens. 1998;11:203-207.
42. Pailleru, CL, Montgermont P, Feder JM, et al. Talking effect and “white coat” effect in hypertensive patients: physical effort or emotional content? Behav Med. 2001;21:149-157.
43. Lynch JJ, Long JM, Thomas, SA, et al. The effects of talking on the blood pressure of hypertensive and normotensive individuals. Psychosom Med. 1981;43:25-33.

PDA Center
AACN Medicopeia 2006 Now
Has Epocrates RxPro Drug Information


Save More Than $200 When You Purchase Medicopeia and a PDA
Medicopeia-The Critical Care Nursing Edition is an innovative subscription program selected by nurses for point-of-care use. Medicopeia is an automatically updated and maintained timesaving solution to your informational needs. Never hassle with downloading or registering again; we do it all for you. When you choose the Palm device that suits your needs, you'll also receive the following software package:

• Epocrates RxPro
• ER + ICU Toolbox
• Pocket ICU Management
• Cardiac Meds E-Reference
• Critical Care Assessment E-Reference
• Hemodynamic Management
E-Reference
• MedCalc
• MedRules
• Adobe Acrobat Reader for Palm
• AACN Critical Care Newsline
• Lifetime Technical Support

For more information or to purchase a PDA, visit www.aacn.org/AACN/conteduc.nsf/vwdoc/PDASpecials or phone (800) 462-0388.

AACN is inviting abstracts for presentation at the National Teaching Institute and Critical Care Exposition, May 19 through 24 in Atlanta, Ga.

Selected abstracts will be exhibited as either a poster or oral presentation. Individuals whose abstracts are accepted will receive a $75 reduction in NTI registration fees.

Four research abstracts will be selected to receive the Research Abstract Award. This award recognizes individuals whose abstracts reflect outstanding original research, replication research or research utilization. Each of the award recipients will present their findings at one of the research oral presentation sessions at NTI and will also receive an additional $1,000 toward NTI expenses.

Sept. 1, 2006, is the deadline to submit research abstracts.

The applications, as well as guidelines and resources, are available online at www.aacn.org > Research > NTI Abstracts.


Congratulations to Research Grant Recipients

AACN-Philips Medical Systems Clinical Outcomes Grant

Co-sponsored by Philips Medical Systems and AACN, three awards up to $10,000 each are available each year to support experienced nurses in conducting clearly articulated research studies. The research must be relevant to clinical nursing practice in acute or critical care. Proposals submitted by an interdisciplinary team or an experienced researcher mentoring a novice are also considered.

The recipients of this award for 2006 are:

Terri L. Brown, CNS, MS, MSN, CPN
Houston, Texas
Outcome Measures for Pediatric Procedural Pain

Brian T. Graves, RN, MS, BA, APRN, ACNP-C
Rochester, N.Y.
Multilevel Modeling of ARDS Mortality Predictors

Mary Lou Sole, RN, CNS, PhD, CCNS, FAAN
Winter Park, Fla.
Assessment of Endotracheal Cuff Pressures With Continuous Monitoring: A Pilot Study

The annual application deadline is Oct. 1.

Evidence-Based Clinical Practice Grant

This program provides awards of $1,000 to stimulate the use of patient-focused data or previously generated research findings to develop, implement and evaluate changes in acute and critical care nursing practice.

The recipients of this award for 2006 are:

Lynne Marie Hancock
Playa del Rey, Calif.
Effects of an Evidence-based Discharge Teaching Protocol on Discharge Teaching Needs of Selected Pediatric Patients

Mary Louise E. Osevala, RN, MSN, CCNS
Shamokin, Pa.
Evidence-Based Strategy to Improve Heart Failure Education

LaTisha Y. Reed, RN, BSN, CCRN
Houston, Texas
Noninvasive Ventilation in Acute Respiratory Failure

Kathleen A. Schell, RN, DNSc
Wilmington, Del.
Clinical Comparison of Forearm and Upper Arm Automatic Noninvasive Blood Pressures in Critically Ill Adults

AACN Critical Care Grant

This grant awards up to $15,000 to support research focused on one or more of AACN’s research priorities.

The recipient of this award for 2006 is:

Holli A. DeVon, RN, PhD
Libertyville, Ill.
An Intervention to Improve Knowledge and Outcomes in Patients at Risk for Acute Coronary Syndromes

Wendy M. Fallis, RN, PhD
Winnipeg, Canada
Family Presence During Resuscitation: Perceptions of Family Members and Healthcare Professionals

The annual application deadline is Jan. 1.

Medtronic Physio-Control AACN Small Projects Grant

This grant funds up to $1,500 to a qualified individual carrying out a project focusing on aspects of acute myocardial infarction, resuscitation or sudden cardiac death. Eligible projects may include patient education programs, staff development programs, competency-based educational programs, CQI projects, outcomes evaluation projects or small clinical research studies.

The recipient of this grant for 2005 is:

Annette J. McDonough, RN, MS, PhD, TNS
Mt. Laurel, N.J.
The Experiences of Young Adults Living With an Implantable Cardioverter Defibrillator (ICD)

July 1 is the annual application deadline for this grant.

AACN-Sigma Theta Tau Critical Care Grant

This $10,000 grant is cosponsored by AACN and Sigma Theta Tau International. The grant may be used to fund research for an academic degree.

The recipient of this award for 2006 is:

Rebecca Cross, MS, MSN, APRN, NP
Los Angeles, Calif.
Impact of Major Depression on Regional Gray Matter Volume in HF Patients

Oct. 1 is the annual application deadline for this grant.

AACN Clinical Inquiry Grant

The clinical inquiry fund provides small awards up to $500 to qualified individuals carrying out clinical research projects that directly benefit patients and/or families. Interdisciplinary projects are especially invited.

The recipients of this grant for 2005 are:

Susan B. Fowler, RN, PhD, CNRN, FAHA
Metuchen, N.J.
Stroke Knowledge of Patients With Atrial Fibrillation

Christine Hedges, PhD, CCRN, CCNS, APRN, RN-BC
Westwood, N.J.
Sleep Quality and Noise Disturbances in a Cardiac/Trauma Progressive Care Unit

Kathleen A. Ohman, RN, EdD, CCRN
Clear Lake, Minn.
Registered Nurses, Physicians and Other Health Care Personnel Attitudes, Concerns, and Beliefs Toward Family Presence During Cardiopulmonary Resuscitation and Bedside Invasive Procedures

Sonja M. Fick, RN, BSN, CCRN-CSC
Long Bottom, Ohio
Family Involvement in Critical Care Units: Nurses Versus Families Perceptions

Linda Bucher, RN, DNS
Marlton, N.J.
Implementation of a Hospital-Wide Guided Imagery Program

The recipient of this grant for 2006 is:

Susan E. Simms, RN, MS, MSN
Gibsonia, Pa.
Self-Efficacy and Self-Care Management of Persons with Heart Failure

Application deadlines each year are Jan. 1 and July 1.

End of Life/Palliative Care Small Projects Grant

This grant awards $500 to carry out a project focusing on end-of-life or palliative care outcomes in critical care.
The recipient of this award for 2005 is:

Cathy H. Schuster, RN, BS, BSN, CCRN
Novato, Calif.
Withdrawal of Life Support Protocol

The recipient of this award for 2006 is:

Connie S. Wilson, RN, MSN, EdD, ScD
Beech Grove, Ind.
Perception of Family Witnessed Resuscitation in Adult Critical Care

Applications for this grant are accepted twice a year and must be received by Jan. 15 or July 1.

AACN Mentorship Grant

This $10,000 grant provides research support for a novice researcher with limited or no research experience to work under the direction of a mentor with expertise in the area of proposed investigation.

The recipient of this grant for 2006 is:

Shannan Kay Hamlin, RN, MSN, CCRN, ACNP, APRN
Pasadena, Texas
Multisite Randomized Clinical Trial of Horizontal Positioning to Prevent and Treat Pulmonary Complications in Mechanically Ventilated Patients: Pilot Study & Hemodynamic Substudy

The annual application deadline for this grant is Feb. 1.

AACN Research Priorities

• Effective and appropriate use of technology to achieve optimal patient assessment, management or outcomes
• Creating a healing, humane environment
• Processes and systems that foster the optimal contribution of critical care nurses
• Effective approaches to symptom management
• Prevention and management of complications