Blood pressure (BP) measurement is an essential element of assessment of the cardiovascular system. Although evidence suggests physical therapists (PTs) are performing these measures at low frequencies in many practice settings, PTs in home healthcare (HHC) report measuring BP at the highest frequency (Frese et al., 2002). Policies and regulations specific to the HHC setting, inclusive of the US Department of Health and Human Services Outcome and Assessment Information Set, could be a contributing factor to higher BP measurement rates by PTs practicing in HHC. Although obtaining a patient's BP reading is an important step in optimizing the health of all patients, assuring the measurement is performed using evidence-based methodology and with well-maintained equipment is a critical component to ensure the validity and reliability of the reading obtained. This Focus on Therapy examines BP measurement and its application to therapists working in the HHC setting.
A BP reading measured at each patient encounter assists in determining if therapeutic interventions are safe to initiate. Although minor day-to-day variations in resting BP are considered normal, significant fluctuations from visit to visit could be an indication of medication noncompliance, dehydration, hypertensive crisis, and sepsis among other conditions. Arena et al. (2014) reported 75% of patient cases managed by HHC PTs had a BP measurement that met the definition of either prehypertensive or hypertensive as defined by the Seventh Report of the Joint National Committee of Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC7). It is notable that The American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines recently released the successor to the JNC7 BP definition (Table 1) (Whelton, 2017). Using these established criteria, a therapist's identification of a new or repeated elevation may warrant further skilled and medically necessary interventions including lifestyle modification education or referral to a physician for medication review and dosing modifications.
Blood pressure can also be useful in the assessment of orthostatic hypotension, which has been associated with mortality, cardiovascular disease, dementia, and fall risk (Benvenuto & Krakoff, 2011). Low BP, especially when combined with abnormal signs or symptoms, may lead therapists toward further examination, differential diagnosis, and clinical decisions as serious medical conditions including dehydration, sepsis, or irregular heart rhythm may be emerging. It is also noteworthy that BP measurement can be a useful tool when screening for peripheral vascular disease through the use of the ankle brachial index (ABI). McDermott et al. (2009) reported mobility loss and an inability to ambulate for 6 continuous minutes to be more likely when comparing individuals with a borderline abnormal ABI value to those with a normal ABI.
Frese et al. (2011) provide recommended guidelines for PTs to consider when measuring BP. Additionally, a protocol modified from the JNC7 and Pickering et al. (2005) for use by therapists when obtaining an auscultatory seated resting BP is outlined in Table 2. Blood pressure readings obtained from the brachial artery have been the standard location for measurements. However, consideration for a hydrostatic effect when using sites distal to the brachial artery (the wrist and forearm) are warranted (Pickering et al.). An appropriately sized cuff should be used for measuring BP as a cuff that is too small may result in a false higher BP reading; whereas, a cuff that is too large may result in a false lower BP reading (Pickering et al.). Timing of the patient's exercise; current pain level; and recent alcohol, nicotine, or caffeine consumption should be considered with each BP measure. Furthermore, environmental factors including room temperature and background noise may impact the BP reading obtained.
Routine maintenance of equipment is a prerequisite to assuring a therapist obtains a valid and reliable BP measure. Arena et al. (2016) reported 21.6% of BP devices being used by HHC providers were not in calibration, and an additional 14.9% were not in working order due to tears, excessive wear, or bulb malfunction. Routine maintenance of BP equipment is vital. Although some clinicians may choose to utilize an automated BP cuff, Skirton et al. (2011) suggest there are situations for which a manual/auscultatory measurement may be preferred. Specifically, an auscultatory measurement should be considered among patients with hypertension, cardiac arrhythmias, after a trauma, in the presence of labile conditions, or when a high degree of accuracy is required.
Blood pressure measurement can be a useful and necessary assessment tool for therapists practicing within the HHC setting; however, consideration for measurement methodology and equipment maintenance are essential to obtaining a valid and reliable measure from which to make informed clinical decisions.
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