The measurement of blood pressure is a common but critical nursing assessment tool. Since many important clinical decisions are based on blood pressure measurements, these measurements must be accurate and based on precise standards of practice. Professional nursing students need to be taught these standards, and to recognize and appreciate the significance of this important skill.
One purpose of this study was to determine to what extent nursing students who have been taught the American Heart Association (AHA) standards for blood pressure measurement in a laboratory setting actually comply with those standards when practicing in a clinical setting. A second purpose was to determine what factors influence student compliance with the AHA standards. The population consisted of senior-level nursing students enrolled in a baccalaureate nursing program. A descriptive survey design was used. Two categories of information were collected. The first category of data was actual observation of the students' technique in measuring clients' blood pressures. The second category of data was collected via questionnaire to determine what factors influence students' compliance to the AHA standards.
Review of the Literature
This study originated because of an ongoing concern of the investigators regarding student compliance to AHA standards for blood pressure measurement. This concern was prompted by the investigators' observations and impressions, and by the results of a study completed by the Ohio Department of Health (ODH, 1983) in 1981. The ODH study involved a survey of the schools of nursing in the state to determine what students were being taught regarding blood pressure measurement. The completed survey revealed that a wide range of different techniques was being taught and that a great deal of confusion existed as to what schools believed constituted proper technique.
In a follow-up study in 1982, ODH researchers surveyed Ohio hospitals to determine if hospital procedures were in line with "nationally accepted standards" as outlined by the AHA. The results of the survey revealed that a discrepancy existed between the techniques the schools taught and the procedures used in the hospitals where students received their clinical experience. It also revealed that the practice of even new graduates who had been taught differently tended to follow what was observed in the work setting. As a result of these findings, the ODH researchers recommended that providers be alerted to the gap between technique standards and common practice. The study concluded that measurement technique must be precise and standardized if blood pressure readings are to be accurate and reliable.
A similar study was reported by Bove, Owen, and Hekelman (1989) in which The Education Committee for the Greater Cleveland High Blood Pressure Coalition surveyed 50 educational institutions to determine what was being taught to students regarding accurate blood pressure measurement. Analysis of the data indicated that educational institutions are not adequately preparing students with the skill and knowledge essential to obtain accurate blood pressure readings.
According to Sherwitz, Evans, Hennrikus, and Vallbona (1982), the accuracy of blood pressure readings has been a concern ever since the indirect method of measurement was developed at the turn of the century. In 1986, Thompson, McFarland, Hirsch, Tucker, and Boers suggested that the unskillful use of the stethoscope and sphygmomanometer had resulted in many missed and inaccurate diagnoses and concluded that the nurse must know how to use these instruments properly and to interpret the findings correctly. In analyzing the many factors affecting blood pressure readings, Grancio (1981) concluded that accuracy is dependent on absolute adherence to standards of measurement. The standards she identified were those of the AHA.
In their study, Scherwitz et al. (1982) found that the procedures used by nurses for taking blood pressure were far from ideal. They further determined that the techniques for measuring blood pressure differed widely among nurses, with some aspects being done well and others being done poorly by each nurse. They concluded that if the recommendations of the AHA had been used as guidelines in determining blood pressure, then the participants could have substantially improved their technique.
Hill and Grim (1991) emphasize that while blood pressure varies from minute to minute and is influenced by a variety of factors, its exact measurement at a given moment is the basis for vital clinical decisions. These decisions could involve, for example, the adjustment of antihypertensive drug therapy or the induction of labor. The authors conclude that it is therefore crucial to eliminate all possible sources of error when measuring blood pressure and that rigorous attention be paid to actual technique.
Asiain, Montes, Costa-Ramos, and Imizcoz (1990) concluded from their study that both methods of blood pressure measurement, direct and indirect, are highly influenced by technical details that have to be carefully standardized if valid research values can be obtained.
A descriptive survey design was used for the study with two categories of information being collected. The first category included actual observations of the students' performance of blood pressure measurement in community settings. The second category of data was collected by questionnaire to determine the extent to which certain factors might influence the students' compliance with AHA standards for blood pressure measurement.
The population chosen for this study consisted of senior nursing students enrolled in a baccalaureate program at a midwestern university. The convenience sample (JV = 42) for the first category of data collection was made up of students who had been taught the AHA standards for blood pressure measurement at the sophomore level. At the time of the study, these students were seniors assigned to clinical settings in the community where they could easily be observed performing blood pressure screening.
During the first phase of data collection, 42 students were observed taking blood pressures in a community setting to determine their utilization of the AHA standards. The students were aware of being observed by their instructors in a general sense, but were not aware that their technique for measuring blood pressure was specifically being observed. The observers were three graduate students in nursing who had not been involved previously in the students' educational process. These observers were chosen to minimize the likelihood of the students altering their technique to impress a person that they identified as an educator. The tool used by the observers for data collection consisted of the step-by-step recommended procedure for blood pressure measurement as set forth by the AHA (1985). As each student took a blood pressure measurement, the observer recorded compliance or noncompliance with each step of the procedure. No attempt was made by the investigator or the observers to control the environment or to create an ideal situation in which the AHA standards could easily be followed.
For the second phase of data collection, a questionnaire was administered to 17 senior-level students. The questionnaire listed 11 situations or factors that the investigators believed could influence, directly or indirectly, student compliance to the AHA standards. The students were asked to identify which situation or factor, "always," "usually," "sometimes," or "never* existed. The questionnaire was designed to determine student perceptions as to whether co-workers, peers, and the clinical agencies were in compliance with the AHA standards, whether faculty reinforced the standards, whether the physical surroundings were such that the standards could be utilized, and whether adequate time was available to implement the AHA standards. Students also were asked to indicate to what extent they believed the AHA standards to be reasonable and accurate.
None of the students complied with every step of the recommended procedure. Although 100% complied with four of the steps, the investigators did not consider these steps unique to the AHA standards. They included approaching the client in a relaxed manner, wrapping the cuff snugly and smoothly around the arm, positioning oneself no more than three feet from the gauge of the sphygmomanometer, and, at the conclusion of the procedure, recording the reading.
Over 57% of the students failed to comply with five of the recommended steps, involving proper placement of the cuff, estimation of the systolic blood pressure by palpation, calculation of the maximum inflation level, and proper placement of the stethoscope. Ninety-three percent of the students failed to comply with two steps involving determination of the correct arm to use in blood pressure measurement. Each of these seven steps is emphasized by the AHA as being vitally important to accurate blood pressure measurement.
The data derived from the questionnaire revealed that the students often considered themselves to be in situations that were not conducive to performing blood pressure measurement according to AHA standards. Physical surroundings and time were cited as frequent barriers to compliance. According to 65% of the respondents, the physical surroundings were "sometimes" or "never" conducive for carrying out the procedure; 53% said sufficient time was "sometimes* or "never" available. Only 12% of the students perceived the agency procedural standards as "always" being compliant with the AHA standards; 35% said the agency standards were "never* in compliance. Eighly-three percent indicated that the available equipment was "always* or "usually" adequate and in good working order.
The studente also indicated that other individuals influence their compliance. When asked if their clinical instructors reinforce the AHA standards, 6% answered "always," 24% said "usually," 47% said "sometimes," and 24% said "never." The figures were almost identical relative to co-worker and peer compliance. Seventyone percent indicated their belief that the AHA procedure is "always" (24%) or "usually" (47%) reasonable for blood pressure measurement, and 88% stated their belief that it "always" (41%) or "usually* (47%) provides an accurate reading of blood pressure measurement.
The findings of this study support the perceptions previously set forth in the literature regarding the lack of adherence to precise and accurate technique in performing blood pressure measurement. The finding that nursing students did not comply fully with the AHA standards for blood pressure measurement in a clinical setting, even when they had been taught those standards in a laboratory setting, is an example of this. A further finding not previously reported in the literature is that compliance to standards seems to be related to factors of logistics and to the attitudes of others.
The findings point out several areas of concern that have implications for nursing education. The findings indicate that 71% of the students felt that nursing educators "sometimes" or "never" reinforce the need for using the AHA standards. If these standards are not being reinforced consistently throughout an educational program, is a message being given to students that the AHA standards are not of high value and/or are not necessarily considered "common practice"?
There are also important implications for practice in that many critical clinical decisions are based on blood pressure readings. If the preciseness of these readings is in doubt, then the question arises as to whether these clinical decisions are baaed on inaccurate or invalid information. Also, in relation to practice, the study findings indicate that time is an influencing factor in determining a person's decision to use the AHA standards. Given the rapid pace of care delivery in acute care institutions, perhaps in the interest of time, the protocol necessary for accurate blood pressure measurement is not being followed. In other words, nurses may be sacrificing accuracy in the interest of expethency.
As previously noted, the study reflects that factors of logistics influence compliance to the standards. Therefore, educators and administrators need to be certain that the logistics are such that students and practicing nurses are able to, and are encouraged to, comply with the protocol set forth by the AHA.
Consideration also needs to be given to research and technology development regarding blood pressure measurement. Further research is in order to determine alternatives and options for assessing blood pressure in an expethent manner.
In conclusion, no individual student complied with every step of the recommended procedure. In fact, 95% failed to comply with some specific steps that are unique to the AHA standards and that experts consider critical to accurate blood pressure measurement. Response to the questionnaire revealed that factors of logistics and attitudes of others influence student compliance or at least make the situation less conducive to adhering to the AHA standards. An additional interesting finding from the questionnaire was that while students may not have complied entirely with the AHA standards, they believed the procedure to be reasonable and to provide an accurate reading of blood pressure.
- American Heart Association Maryland Affiliate, Inc. (1985). Blood pressure: Its control and measurement (4th ed.). Maryland: Author.
- Aeiain, M.C., Montes, Y, Costa-Ramos, M.L., & Imizcoz, P. (1990). Blood pressure measurement: An evaluation of direct and indirect methods. Intensive Care Nursing, 6, HI117.
- Bove, P.A., Owen, L., & Hekelman, P.P. (1989). Investigation of the methods used to teach blood pressure measurement techniques. Health Values: Achieving High Level Wellness, 73(3), 36-42.
- Grancio, S.D. (1981). Opportunities for nurses in high blood pressure control. Nursing Clinics of North America, 16, 309-320.
- Hill, M., & Grim, C. (1991). How to take a precise blood pressure. American Journal of Nursing, 91, 38-42.
- Ohio Department of Health (1983). Blood pressure measurement technique used by nurses in Ohio. Unpublished manuscript. Columbus: Ohio Department of Health.
- Sherwitz, L., Evans, L., Hennrikus, D-, & VaIlbona, C. (1982). Procedures end discrepancies of blood pressure measurements in two community health centers. Medical Care, 22, 727-738.
- Thompson, J.M., McFarland, O.K., Hirsch, J.E., Tucker, S.M., & Boers, A.C. (19T6). Clinical nursing. St. Louis, MO: Mosby.