Johnston W E, Robertie P G, Butterworth J F, Royster R L, Kon N D
Department of Anesthesia, Wake Forest University Medical Center, Winston-Salem, NC 27157-1009.
J Cardiothorac Vasc Anesth. 1992 Oct;6(5):528-34. doi: 10.1016/1053-0770(92)90094-n.
To determine whether ephedrine or CaCl2 improves hemodynamics in cardiac surgery patients emerging from cardiopulmonary bypass, three sequential doses of either CaCl2 (200 mg/dose; n = 12), ephedrine (5 mg/dose; n = 12), or placebo (n = 12) were administered in a prospective, randomized, double-blind fashion. Thermodilution volumetric catheters were used to calculate right ventricular (RV) volumes and ejection fraction. The first dose of ephedrine improved RV stroke volume from 57 +/- 3 to 63 +/- 4 mL/beat (P < 0.05) and ejection fraction from 44 +/- 2% to 49 +/- 2% (P < 0.05). Subsequent doses maintained this improvement but without further change. In contrast, placebo and CaCl2 had minimal effects on RV end-systolic volume, stroke volume, and ejection fraction. After the third injection of ephedrine, mean arterial pressure had significantly increased from 78 +/- 2 to 93 +/- 4 mmHg (P < 0.05) in contrast to insignificant increments with placebo and CaCl2. Serum ionized calcium increased by 6% to 8% after each CaCl2 bolus but remained stable in the ephedrine and placebo groups. CaCl2 failed to improve RV performance in mildly hypocalcemic patients during separation from cardiopulmonary bypass. In patients with normal preoperative ventricular function, ephedrine more effectively improved RV performance and arterial blood pressure than placebo or CaCl2, and is a suitable short-acting drug to assist separation from cardiopulmonary bypass.
为确定麻黄碱或氯化钙能否改善心脏手术患者体外循环后出现的血流动力学，以前瞻性、随机、双盲方式给予三个连续剂量的氯化钙（200mg/剂量；n = 12）、麻黄碱（5mg/剂量；n = 12）或安慰剂（n = 12）。使用热稀释容积导管计算右心室（RV）容积和射血分数。麻黄碱的首剂使右心室每搏量从57±3ml/次增加至63±4ml/次（P<0.05），射血分数从44±2%增加至49±2%（P<0.05）。后续剂量维持了这种改善，但无进一步变化。相比之下，安慰剂和氯化钙对右心室收缩末期容积、每搏量和射血分数影响极小。第三次注射麻黄碱后，平均动脉压从78±2mmHg显著升至93±4mmHg（P<0.05），而安慰剂和氯化钙组的升高不显著。每次推注氯化钙后血清离子钙升高6%至8%，但在麻黄碱和安慰剂组中保持稳定。在体外循环脱离期间，氯化钙未能改善轻度低钙血症患者的右心室功能。在术前心室功能正常的患者中，麻黄碱比安慰剂或氯化钙更有效地改善右心室功能和动脉血压，是一种适合用于辅助体外循环脱离的短效药物。
