Doty D B
Department of Surgery, University of Utah School of Medicine, Salt Lake City.
J Card Surg. 1990 Sep;5(3 Suppl):256-8. doi: 10.1111/jocs.1990.5.3s.256.
Following cardiopulmonary bypass, a series of steps can usually be used to restore function to the heart. A low postbypass cardiac output can be countered with a response checklist that includes adjusting heart rate, correcting cardiac arrhythmia, ensuring adequate hematocrit, adjusting preload and afterload, and stimulating cardiac contractility. It is the surgeon's responsibility to make a thorough investigation of any structural abnormality that may contribute to the low-output state; adequate repair of cardiac defects will often result in an improved hemodynamic state. Hemorrhage is an important cause of poor cardiac performance. Tamponade of the heart is usually due to retained clots associated with hemorrhage after operation and is indicated by a low-output state with equalization and elevation of atrial pressures. In a low-output, postsurgical state, the possibility of residual shunts and obstructions, inadequate valve repair, and closure or inadequate flow through a graft may need to be investigated. Once that has been achieved, the appropriate steps can be taken to improve cardiac performance.
在体外循环后，通常可采取一系列措施来恢复心脏功能。对于体外循环后心输出量低的情况，可通过一份应对清单来处理，其中包括调整心率、纠正心律失常、确保足够的血细胞比容、调整前负荷和后负荷以及增强心肌收缩力。外科医生有责任全面调查任何可能导致低输出状态的结构异常；对心脏缺陷进行充分修复通常会改善血流动力学状态。出血是心脏功能不佳的一个重要原因。心脏压塞通常是由于术后出血伴有血凝块残留所致，表现为低输出状态且心房压力均衡和升高。在术后低输出状态下，可能需要调查残余分流和梗阻、瓣膜修复不充分以及移植物闭合或血流不足的可能性。一旦完成调查，就可采取适当措施来改善心脏功能。
