Keagy B A, Wilcox B R, Lucas C L, Hsiao H S, Henry G W, Baudino M, Bornzin G
J Thorac Cardiovasc Surg. 1987 May;93(5):658-64.
A new method has been developed that permits constant postoperative monitoring of mean and phasic cardiac output in patients after correction of congenital heart defects. A miniature ultrasound probe is attached to the adventitia of the ascending aorta at the conclusion of the operative procedure. This is connected to the monitoring equipment by means of polyurethane-covered wires that exit the chest wall through a small stab wound. The probe can easily be removed by gentle traction when the patient's condition is stable. The technique was developed, validated, and refined in extensive animal studies, and this report describes the first series of 20 consecutive human implants, performed between August 1984 and September 1985, in which the absolute cardiac output determination obtained with the ultrasound probe at the time of its application was correlated with cardiac output as measured with a standard electromagnetic flow probe. Fourteen male and six female patients (mean age 5.5 years) were studied. Operations performed included eight atrial septal defect repairs, four procedures for tetralogy of Fallot, three ventricular septal defect repairs, three stenotic valve corrections, and two Senning operations. One operative death occurred, but no complications were related to probe application or removal. The average cardiac output in the 20 patients as measured with the ultrasound probe was 2.2 +/- 1.1 L/min (range 0.67 to 5.27 L/min). This is nearly identical to the results noted with the electromagnetic flow probe, where the mean cardiac output was 2.3 +/- 1.2 L/min (range 0.7 to 6 L/min). Regression analysis revealed a high linear correlation (r = 0.9) between the two techniques. A monitor can display the cardiac output trend with 1 minute updates, which greatly enhance management of intravenous drug therapy and volume administration. In conclusion, this new extraluminal removable probe allows virtually continuous monitoring of the postoperative cardiac output after correction of congenital heart defects and should become a standard technique in the postoperative care of these patients.
一种新方法已被开发出来，可对先天性心脏缺陷矫正术后患者的平均和阶段性心输出量进行术后持续监测。在手术结束时，将一个微型超声探头附着于升主动脉外膜。通过聚氨酯包裹的导线将其与监测设备相连，导线经一个小切口穿出胸壁。当患者病情稳定时，通过轻柔牵拉可轻松移除探头。该技术在大量动物研究中得到开发、验证和完善，本报告描述了1984年8月至1985年9月期间连续进行的首批20例人体植入情况，其中在应用超声探头时用其测得的绝对心输出量与用标准电磁流量探头测得的心输出量相关。研究了14名男性和6名女性患者（平均年龄5.5岁）。实施的手术包括8例房间隔缺损修复术、4例法洛四联症手术、3例室间隔缺损修复术、3例狭窄瓣膜矫正术和2例森宁手术。发生了1例手术死亡，但未出现与探头应用或移除相关的并发症。用超声探头测得的20例患者的平均心输出量为2.2±1.1升/分钟（范围0.67至5.27升/分钟）。这与电磁流量探头测得的结果几乎相同，其平均心输出量为2.3±1.2升/分钟（范围0.7至6升/分钟）。回归分析显示两种技术之间存在高度线性相关性（r = 0.9）。一台监测仪可每1分钟更新显示心输出量趋势，这极大地增强了静脉药物治疗和容量管理。总之，这种新型管外可移除探头可对先天性心脏缺陷矫正术后的心输出量进行几乎连续的监测，应成为这些患者术后护理的标准技术。
