tailieunhanh - Cardiac Surgery in Chronic Renal Failure - part 7

Việc sử dụng intraoperative của siêu lọc là rất hữu ích trong việc loại bỏ các nước tự do. Siêu lọc sử dụng áp lực thủy tĩnh trên một màng bán thấm để tạo điều kiện thuận lợi cho việc tập trung của khối lượng máu lưu thông. | Cardiopulmonary bypass in patients with chronic renal failure 55 the time on CPB by using a closed system will reduce the amount of fluid shifted to the interstitial spaces. The intraoperative use of ultrafiltration is very useful in the removal of free water. Ultrafiltration uses hydrostatic pressure across a semiper-meable membrane to facilitate the concentration of circulating blood volume. Postoperative complications from fluid overload such as pulmonary edema impaired hemostasis lowered hematocrit and circulating mediators of the systemic inflammatory response can be mitigated through the judicious administration of fluids and the liberal use of ultrafiltration 11-14 . Darup and colleagues were the first to describe the use of ultrafiltration in conjunction with CPB in 1979 15 . With improvements in filter designs and construction processes using ultrafiltration parallel to CPB has become a standard of practice for the CRF patient. Bridging the ultrafiltration blood path from the recirculation line on the CPB circuit to the cardiotomy reservoir provides flexibility in its utilization 9 . Ultrafiltration in parallel with the CPB circuit flow alleviates the need for a separate dedicated pump head. This configuration also allows for use of the hemoconcentrator for concentration of the remaining blood volume in the circuit at the termination ofbypass in a modified ultrafiltration setup. Electrolyte management While the goal of electrolyte management is to maintain all electrolytes within normal parameters potassium deserves most of the attention. Lifethreatening dysrhythmias are directly related to elevated or reduced levels of potassium. Hyperkalemia during the perioperative period has multiple sources which include the following decreased or absent potassium excretion type of crystalloid solution used for priming cardioplegia solution hemolysis blood trauma infused blood products drugs . succinylcholine and acid base balance management. The management of .