Guss David A, Abdelnur Diego, Hemingway Thomas J
Department of Emergency Medicine, University of California, San Diego Medical Center, San Diego, California 92103, USA.
J Emerg Med. 2008 May;34(4):377-82. doi: 10.1016/j.jemermed.2007.05.049. Epub 2008 Jan 4.
Blood pressure is a standard vital sign in patients evaluated in an Emergency Department. The American Heart Association has recommended a preferred position of the arm and cuff when measuring blood pressure. There is no formal recommendation for arm position when measuring orthostatic blood pressure. The objective of this study was to assess the impact of different arm positions on the measurement of postural changes in blood pressure. This was a prospective, unblinded, convenience study involving Emergency Department patients with complaints unrelated to cardiovascular instability. Repeated blood pressure measurements were obtained using an automatic non-invasive device with each subject in a supine and standing position and with the arm parallel and perpendicular to the torso. Orthostatic hypotension was defined as a difference of >or= 20 mm Hg systolic or >or= 10 mm Hg diastolic when subtracting standing from supine measurements. There were four comparisons made: group W, arm perpendicular supine and standing; group X, arm parallel supine and standing; group Y, arm parallel supine and perpendicular standing; and group Z, arm perpendicular supine and parallel standing. There were 100 patients enrolled, 55 men, mean age 44 years. Four blood pressure measurements were obtained on each patient. The percentage of patients meeting orthostatic hypotension criteria in each group was: W systolic 6% (95% CI 1%, 11%), diastolic 4% (95% CI 0%, 8%), X systolic 8% (95% CI 3%, 13%), diastolic 9% (95% CI 3%, 13%), Y systolic 19% (95% CI 11%, 27%), diastolic 30% (95% CI 21%, 39%), Z systolic 2% (95% CI 0%, 5%), diastolic 2% (95% CI 0%, 5%). Comparison of Group Y vs. X, Z, and W was statistically significant (p < 0.0001). Arm position has a significant impact on determination of postural changes in blood pressure. The combination of the arm parallel when supine and perpendicular when standing may significantly overestimate the orthostatic change. Arm position should be held constant in supine and standing positions when assessing for orthostatic change in blood pressure.
血压是在急诊科接受评估的患者的一项标准生命体征。美国心脏协会推荐了测量血压时手臂和袖带的最佳位置。在测量直立性血压时，对于手臂位置没有正式的推荐。本研究的目的是评估不同手臂位置对血压姿势变化测量的影响。这是一项前瞻性、非盲法、便利性研究，纳入了主诉与心血管不稳定无关的急诊科患者。使用自动无创设备，让每位受试者处于仰卧位和站立位，且手臂与躯干平行和垂直时，重复测量血压。直立性低血压定义为仰卧位测量值减去站立位测量值时，收缩压差值≥20 mmHg或舒张压差值≥10 mmHg。进行了四项比较：W组，手臂垂直位仰卧和站立；X组，手臂平行位仰卧和站立；Y组，手臂平行位仰卧和垂直位站立；Z组，手臂垂直位仰卧和平行位站立。共纳入100例患者，55例男性，平均年龄44岁。对每位患者进行了四次血压测量。每组中符合直立性低血压标准的患者百分比为：W组收缩压6%（95%可信区间1%，11%），舒张压4%（95%可信区间0%，8%）；X组收缩压8%（95%可信区间3%，13%），舒张压9%（95%可信区间3%，13%）；Y组收缩压19%（95%可信区间11%，27%），舒张压30%（95%可信区间21%，39%）；Z组收缩压2%（95%可信区间0%，5%），舒张压2%（95%可信区间0%，5%）。Y组与X组、Z组和W组的比较具有统计学意义（p<0.0001）。手臂位置对血压姿势变化的测定有显著影响。仰卧时手臂平行而站立时手臂垂直的组合可能会显著高估直立性变化。在评估血压的直立性变化时，仰卧位和站立位时的手臂位置应保持恒定。
