Witting M D, Wears R L, Li S
Division of Emergency Medicine, University of Florida Health Science Center, Jacksonville.
Ann Emerg Med. 1994 Jun;23(6):1320-3. doi: 10.1016/s0196-0644(94)70358-2.
To define a set of orthostatic vital signs that minimize the frequency of false-positives among healthy individuals while maximizing sensitivity in detecting acute moderate blood loss and to determine the sensitivity and specificity of this optimized tilt test in detecting acute moderate blood loss.
Postural vital signs were recorded in a standardized manner before and after 450-mL phlebotomy. Paired comparisons were done for a variety of criteria for a positive tilt test using receiver-operating characteristic curves.
Three hundred forty-five healthy euvolemic adult volunteer blood donors were tested at three community blood donation centers over a one-year period. Subjects were prospectively divided into group 1 (less than age 65; 301) and group 2 (age 65 or older; 44).
For each combination of pulse and blood pressure in group 1, a change in pulse alone had the same or higher sensitivity with at least the same specificity. Pulse alone was similarly superior in group 2 compared with previously published combinations of pulse and blood pressure. Even the optimized tilt test had limited sensitivity in detecting acute moderate blood loss with high specificity.
In applying the tilt test to young adults without cardiovascular disease, pulse measurement usually is all that is necessary.
定义一组直立位生命体征，以尽量减少健康个体中假阳性的频率，同时在检测急性中度失血时最大化敏感性，并确定这种优化倾斜试验在检测急性中度失血时的敏感性和特异性。
在抽取450毫升静脉血前后，以标准化方式记录体位生命体征。使用受试者操作特征曲线，对多种阳性倾斜试验标准进行配对比较。
在一年时间内，对三个社区献血中心的345名健康、血容量正常的成年志愿献血者进行了测试。受试者被前瞻性地分为第1组（年龄小于65岁；301人）和第2组（年龄65岁及以上；44人）。
对于第1组中脉搏和血压的每种组合，仅脉搏变化具有相同或更高的敏感性，且特异性至少相同。与先前公布的脉搏和血压组合相比，第2组中仅脉搏同样具有优势。即使是优化的倾斜试验，在检测急性中度失血时敏感性也有限，但特异性较高。
在将倾斜试验应用于无心血管疾病的年轻人时，通常仅测量脉搏就足够了。
