Body Structures Determining Differences in Forearm and Upper Arm Blood Pressures

Accurate blood pressure (BP) measurement is required to provide appropriate healthcare. Inaccurate BPs may lead to under and/or over-treatment of health conditions and medical diseases such as hypertension. Blood pressure (BP) measurement using automatic, non-invasive oscillometric monitors is common in clinics, physicians'offices and hospital settings. The brachial (upper arm) site is the gold standard for non-invasive BPs. However, in some situations, this site is inaccessible due to injury, surgery, dialysis shunts, intravenous devices, and lymphedema. When the upper arm is difficult to access or the available BP cuffs do not fit an individual's arm, the forearm site is often the preferable alternative. The increased incidence of obesity nationally also contributes to the heightened use of forearm BPs. Questions remain concerning the accuracy of forearm non-invasive BP measurements. Although most researchers report that upper arm and forearm readings are not interchangeable, size of differences vary for individuals and factors influencing differences in readings have not been thoroughly investigated.