Introduction
Blood pressure is essentially a product of heart output and peripheral resistance. Heart output is reflective of atrial/ventricle capacity and myocardial condition. Peripheral resistance relates to the arterial lumen and muscle.
Blood pressure (BP) measurement is the most basic medical examination performed on any patient reporting to a health care facility. Therefore, it is the most popular activity performed by health care practitioners (Netea & Thien, 2004, p. 301). Schell, Bradley, Bucher, Sekel, Lyons, Wakai, & Simpson (2005), asserts that BP measurements are important for screening hypertension; assessing cardiovascular risk (p. 235); and diagnosing, control and treating chronic and acute clinical conditions (Dobbin, 2002, p. 124). The perfect measurement is critical for appropriate diagnosis, control, and treatment of high blood pressure, and clinical judgment in acute care settings.
Like any other health parameter, BP measurement is prone to errors. BP measurement is comparatively simple to conduct, although errors associated with the observer, device, or lack of standardized technique and the condition of measurement can promote inaccurate blood pressure reading (Netea, Lenders, Smit, & Thien, 2003, p. 239).
Other factors that contribute to erroneous reading include environment, malfunctioned device, arm position, body position, cuff size relative to arms size, and site of measurement.
Traditionally, the site for BP measurement has been the upper arm. Nevertheless, medical devices may impede upper arm making it inaccessible for BP measurement. Large cuffs, also, may not be available for BP measurement in obese patients. In such cases, the forearm may be a choice of location for the BP measurement device (Schell et al., 2005, p. 234). Typically, a region where clinician can palpate an artery against a bone, offers the appropriate condition for feeling the pulse.
Overview
The location of equipment for BP measurement determines the accuracy of the measurement. Netea and Thien (2004), propose the direct intra-arterial technique as the gold standard for BP measurement, although it is invasive and unreasonable (p. 299). Previously, clinicians used a sphygmomanometer and stethoscope to measure BP from the upper arm (Netea & Thien, 2004, p. 303). Electronic manometers, which are non-invasive, have replaced the sphygmomanometer and stethoscope for BP measurement in hospitals. Unlike sphygmomanometers, electronic manometers provide more accurate and safe means of reading BP.
This paper describes a study that Anderson, D., Anderson, M. and Hill conducted in 2010 to determine the factors that influence BP accuracy, the prevalence of forearm location for BP measurement, and factors that influence care workers’ choice of forearm for BP measurement (p. 289).
The study involved specific health care practitioners in a rural community hospital. The researchers employed a quantitative, explanatory, non-experimental design. The scientist developed a researcher-designed tool termed the Blood Pressure Accuracy Form (BPAF) for use in the study. The researchers met ethical requirements pertaining to the study.
The study divided its findings into three classes. The first class constituted of the factors that the health care workers perceived as having the greatest influence on the BP. The second concerned the prevalence of the forearm as the location for BP measurement. The third class concerned the factors, which can influence the clinician to apply the forearm as the alternate location for BP measurement.
Health care workers perceived cuff size as having the greatest influence on BP accuracy, followed by arm orientation, location of measurement, and position of the patient. The study, also, indicated that approximately 90% of respondents had taken BP measurements from the forearm and had included the option into clinical practice. In addition, RNs in departments such as, ER and ICU were less likely to take the BP in the forearm.
Moreover, the Upper Arm Circumference (UAC) plays an important role in BP accuracy. The UAC at the shoulder is not equal to that of the elbow, thereby giving the arm a cone shape implying a non-uniform compression of the brachial artery. Equipment challenges, also, contributed to the choice of forearm for BP measurement. The clinicians cited unavailability and malfunctioning of the equipment as a major factor contributing to use of the forearm.
Conclusion
Medical or nursing school educators must properly train Health care personnel to perform BP measurement in a conscientious manner, with focus on cuff size, patient placement, arm position, and site of measurement. From the second perspective, the practice of reading the BP from the forearm is universal and non-dependent on educational background or experience.
Regarding recognizing the importance of factors that influence BP accuracy, re-education for all staff is important regarding the physiology of BP determination taking into account all variables of similar significance. A longer, broader cuff is necessary for enough compression of the brachial artery in obese patients.
When a clinician mustread BP from the forearm, she must ensure that the position of the forearm is about the same level as the heart. Because the BP measurement from the forearm is an overestimation of the actual BP staff and patient education should overrule the choice of the forearm, based on ease and comfort. The reading of BP from the forearm leads to an overestimation of the systolic pressure, thus the clinician should clarify the location of BP measurement in the medical record. In addition, the lack of available diverse cuff sizes and equipment in non-working order compel clinicians to choose forearm for BP measurement.
Policies and procedures pertaining to BP measurement must depict current standards of evidence-based practice. Processes must be standardized and imposed throughout the entire organization.
Although this was a private study, conducted in a rural background, it could similarly apply to an urban hospital. Such application would be important to establish whether the study can generalize the outcomes to other facilities. The generalization would benefit a more diverse population.
Certain clinical conditions, including mastectomy, requires the application of the forearm as the location for BP measurement; nevertheless, such conditions are few and practitioners should assess them carefully. Clinicians must exhaust all possibilities in obtaining a proper cuff size before using the forearm for reading BP. The clinicians should not consider their patient’s requests. The clinician must indicate in the medical record, the location of BP measurement need not be the upper arm.
Reference list
Anderson, D. J., Anderson, M. A., & Hill, P. D. (2010). Location of Blood Pressure Measurement: Research for practice. MEDSURG Nursing, 19(5), 287-294
Dobbin, K. (2002). Noninvasive blood pressure monitoring. Critical Care Nurse, 22(2), 123-124.
Netea, R. T., Lenders, J., Smits, P., & Thien, T. (2003). Influence of body and arm Position on blood pressure readings: An overview. Journal of Hypertension, 21(2), 237-241.
Netea, R.T., & Thien, T. (2004). Blood pressure measurement: We should all do it Better! The Netherlands Journal of Medicine, 62(8), 297-303.
Schell, K., Bradley, E., Bucher, L., Sekel, M., Lyons, D., Wakai, S., & Simpson, K. (2005). Clinical comparison of automatic, noninvasive measurements of blood pressure in the forearm and upper arm. American Journal of Critical Care, 14(3), 232-241.