Bush H L, LoGerfo F W, Weisel R D, Mannick J A, Hechtman H B
Arch Surg. 1977 Nov;112(11):1301-5. doi: 10.1001/archsurg.1977.01370110035003.
Myocardial depression has been suggested as a cause of declamping hypotension. To investigate and manage this problem, thermal dilution catheters were placed in 22 elderly, high-risk patients (mean age 71 years) who underwent elective abdominal aortic aneurysm resection. There were no deaths. Myocardial performance curves (MPC) were determined preoperatively, following induction of anesthesia, during aortic clamping, following declamping, and 12 to 48 hours postoperatively. The slope of this curve was taken as an index of myocardial performance. Preoperative cardiac index at a pulmonary artery wedge pressure of 10 mm Hg (CI10) decreased significantly following induction of anesthesia (P less than .002) and persisted during aortic cross-clamping. Following declamping, CI10 rose to preoperative levels. The slope of the MPC followed this same pattern. There was no significant change in blood pressure with the aorta clamped or following declamping. Myocardial performance is depressed following induction of anesthesia but declamping hypotension can be minimized or prevented by optimum volume loading as guided by Starling's myocardial performance curves.
心肌抑制被认为是解除钳夹后低血压的一个原因。为了研究和处理这个问题，对22例接受择期腹主动脉瘤切除术的老年高危患者（平均年龄71岁）放置了热稀释导管。无死亡病例。在术前、麻醉诱导后、主动脉钳夹期间、解除钳夹后以及术后12至48小时测定心肌功能曲线（MPC）。该曲线的斜率被用作心肌功能的指标。在肺动脉楔压为10 mmHg时的术前心脏指数（CI10）在麻醉诱导后显著下降（P＜0.002），并在主动脉交叉钳夹期间持续存在。解除钳夹后，CI10升至术前水平。MPC的斜率遵循相同模式。主动脉钳夹期间或解除钳夹后血压无显著变化。麻醉诱导后心肌功能受到抑制，但通过根据Starling心肌功能曲线进行最佳容量负荷调整，可将解除钳夹后低血压降至最低或预防。
