婴幼儿先天性心脏病体外循环术后严重低钾血症的处理策略

目的 探讨高浓度快速静脉补钾的目标性治疗小儿先天性心脏病体外循环术后严重低钾血症的有效性和安全性.方法 80例体外循环术后严重低钾血症随机分成快速组和慢速组,两组静脉补钾的浓度为1.5%～5.0%,两组的速度分别为0.75～1.0mmol·kg~(-1)·h~(-1)和0.3～0.5 mmol·kg~(-1)·h~(-1),用输液泵经中心静脉均匀输入.当血钾≥3.5 mmol/L时两组改为常规补钾治疗.测定补钾前后的血钾浓度、动脉血气分析和心电图,同时持续心电监护、经皮氧饱和度监测和动脉血压监测.结果 两组补钾前血钾浓度相似,但快速组与慢速组相比,静脉补钾时间短(0.83±0.19)h比(2.14±0.27)h,P<0.01,补钾后血钾浓度高(4.07±0.95)mmol/L比(3.49土0.77)mmol/L,P<0.05,血钾浓度增高值与补钾剂量间无显著直线相关关系,两组中均未见高钾血症及与之相关的一过性心律失常.结论 本文采用的高浓度快速静脉补钾的目标性治疗具有快速、有效和安全性,不增加输液量,对纠正婴幼儿先心病体外循环术后严重低钾血症有一定的临床应用价值.

The therapy of severe postoperative hypokalemia after extracorporeal circulation in infants and young children with congenital heart disease

Objective To evaluate the efficacy and safety of rapid correction of severe postoperative hypokalemia after extracorporeal circulation in infant and young children of congenital heart disease using concentrated intravenous potassium infusions. Methods 80 patients with severe hypokalemia after extracorporeal circulation surgery were randomly assigned to rapid and slow correction group, with respectively potassium concentration at 1.5%～5%, potassium chloride infusions via central vein at a respectively rate of 0.75～1.0 mmol/kg·hr and 0.3～0.5 mmol/kg·hr. After plasma potassium concentration ≥3.5 mmol/L, we change to rountine potassium maintenance regiment. Plasma potassium concentration, arterial blood gas analysis(ABG)and electrocardiographic (ECG) were taken before and after therapy, while continuously monitoring the vital signs, arterial blood pressure and oxygen satuation percutaneous. Results Potassium concentrations of two groups before therapy were the same. Time of intravenous potassium replacement in rapid group is 0.83 ±0.19 h, as compared with 2.14 ±0.27 h in slow group, which was notably shorten with P<0.01, the potassium level after intravenous therapy in rapid group was higher than that in slow group, with respective concentrations of 4.07 ±0.95 mmol/L and 3.49 ±0.77 mmol/L, P<0.05.The increment(△K) in serum potassium level was not linear relative with the dosage of given potassium. No hyperkalemia and relative temporally arrhythmias was encountered. Conclusions Rapid target therapy with concentrated intravenous potassium infusions can be used to correct severe postoperative hypokalemia after extracorporeal circulation in infant and young children of CHD safely.