Goertz A W, Schmidt M, Lindner K H, Seefelder C, Georgieff M
Department of Anesthesiology, University of Ulm Medical Center, Germany.
J Clin Anesth. 1993 Sep-Oct;5(5):408-13. doi: 10.1016/0952-8180(93)90106-o.
To investigate the effect of intravenous (IV) phenylephrine (PHE) bolus administration on left ventricular function in patients who developed postural hypotension during isoflurane anesthesia in the head-up tilt (reverse Trendelenburg) position.
Prospective "before-after" trial.
Operation theater of a university medical center.
15 ASA physical status I and II patients without cardiovascular disorders.
The anesthetized patients were tilted from a supine horizontal to a 30-degree reverse-Trendelenburg position. Once a steady state was achieved, PHE 3 micrograms/kg was administered as an IV bolus dose.
Transesophageal echocardiography was used to assess left ventricular function. We measured blood pressure (BP); heart rate; left ventricular end-systolic and end-diastolic area, diameter, and wall thickness; and ejection time at baseline and after tilt, immediately before and for a period of 3 minutes after PHE injection. We calculated fractional area change (FAC), mean velocity of circumferential fiber shortening (mVcf), and end-systolic wall stress. Head-up tilt caused a reduction of mean arterial pressure [from 68 to 54 mmHg (mean)], end-systolic and end-diastolic left ventricular area (from 9.7 to 6.5 cm2 and from 19.2 to 13.1 cm2, respectively) and end-systolic wall stress (from 56 to 33 10(3).dyne/cm2). FAC and mVcf remained unaltered. PHE administration restored baseline values or overcompensated the changes caused by tilt. FAC slightly decreased in response to PHE (from 0.51 to 0.43), end-systolic wall stress increased to 83 10(3).dyne/cm2, and mVcf remained unchanged.
PHE bolus administration effectively restored BP and cardiac filling, which were reduced after head-up tilt, without causing a relevant impairment of left ventricular function or an increase in end-systolic wall stress above the upper normal limit.
探讨静脉推注去氧肾上腺素（PHE）对在异氟烷麻醉下头高位倾斜（反式特伦德伦伯卧位）时发生体位性低血压患者左心室功能的影响。
前瞻性“前后”试验。
大学医学中心的手术室。
15例美国麻醉医师协会（ASA）身体状况为I级和II级且无心血管疾病的患者。
将麻醉后的患者从仰卧水平位倾斜至30度反式特伦德伦伯卧位。一旦达到稳定状态，以3微克/千克的剂量静脉推注PHE。
采用经食管超声心动图评估左心室功能。我们测量了血压（BP）、心率、左心室收缩末期和舒张末期面积、直径及壁厚度，以及在基线、倾斜后、注射PHE前即刻及注射后3分钟内的射血时间。我们计算了面积变化分数（FAC）、圆周纤维缩短平均速度（mVcf）和收缩末期壁应力。头高位倾斜导致平均动脉压降低[从68降至54 mmHg（平均值）]、左心室收缩末期和舒张末期面积减小（分别从9.7降至6.5 cm²和从19.2降至13.1 cm²）以及收缩末期壁应力降低（从56降至33×10³达因/平方厘米）。FAC和mVcf保持不变。注射PHE后恢复了基线值或过度补偿了倾斜引起的变化。FAC因PHE而略有降低（从0.51降至0.43），收缩末期壁应力增至83×10³达因/平方厘米，而mVcf保持不变。
静脉推注PHE有效恢复了头高位倾斜后降低的血压和心脏充盈，且未引起左心室功能的相关损害或使收缩末期壁应力增加至正常上限以上。
