脓毒症患儿的持续血液净化治疗22例分析

Continuous blood purification therapy in 22 children with sepsis

目的采用持续血液净化(Continuous Blood Purification,CBP)救治儿童严重脓毒症合并脏器功能障碍,观察其临床疗效。方法对2003年8月—2005年8月,我院收治的22例儿童严重脓毒血症进行持续静脉静脉血液透析滤过(Continuous Vein-Vein Hemodialysis Filtration,CVVHDF),观察心率、血压、血管活性药物使用、自主呼吸频率、氧合指数的变化以及预后。结果22例均顺利置管并完成CBP,CBP持续时间为(64．4±34．5)h。CBP前均存在心动过速,CBP 4h下降(45±13)次/ min；CBP后,未休克的7例血压平稳；10例早期休克患儿CBP后血压维持正常,血管活性药物1～5h下调,2～8h撤除；5例难治性休克患儿CBP 4h后血压明显上升,升高幅度为(25．2±10．7)mm Hg (1mm Hg=0．133 kPa),8h恢复到该年龄正常水平,血管活性药物在CBP 2～8h下凋,4～16h停用,较早期休克患儿略延长。呼吸频率增加的患儿CBP 4h后自主频率减慢(7±4)次/min；合并呼吸衰竭患儿CBP前氧合指数(PO_2/FiO_2)为(177．7±53．1)mm Hg,CBP后4h上升至(341．0±60．2) mm Hg,(5．3±2．1)h全部达到正常；吸入氧浓度FiO_2 2～4h降至50%以内。危重评分入院时62．2±7．4,24h升高至危重评分86．6±9．0,提高24．5±10．8；CBP治疗后存活16例,存活率72．7%,治疗有效率90．9%。置换液采用改良Ports方案可导致血钙、血糖和血渗透压的升高。CBP在脓毒症患儿应用可能引起转流初期的血压轻度下降和转流过程中的出血现象。结论持续血液净化有改善严重脓毒血症儿童重要脏器的作用。

Objective Since continuous blood purification （CBP） has the effects of eliminating inflammatory mediators and improving organs function, CBP had been applied to treat non-renal diseases for nearly 10 years, but few studies have been conducted in children with sepsis and muhiorgan dysfunction syndrome（ MODS）, especially in China. The present study aimed to evaluate the clinical effect of CBP in treatment of children with severe sepsis and MODS. Methods Twenty-two children with severe sepsis and MODS admitted to our PICU from Aug. 2003 to Aug. 2005 were treated with continuous veno-venous hemodialysis filtration. Their heart rate, arterial blood pressure, doses of vasoactive agents, spontaneous repiratory rate, PO2/FiO2 and prognosis were investigated. Results Catheterization and CBP were carried out in all the 22 children. Continuous vein-vein hemodialysis filtration （CVVHDF） and pre-dilution were chosen. The duration of CBP was （ 64. 4±34.5 ） h. All the children had tachycardia before CBP and the heart rate fell gradually to 45 ± 13 bpm 4 h after CBP. Blood pressure （BP） was stable in 7 children without shock during CBP. Ten children with early shock could maintain normal BP during CBP, but the doses of vasoactive agents were tapered 1 to 5 h after beginning of CBP and use of these agents was discontinued at 2 to 8 h. BP was elevated by （25.2 ± 10. 7） mmHg （ 1 mmHg =0. 133 kPa） in5 refractorily shocked children 4 h after CBP and returned to normal level 8 h later. The doses of the vasoactive drugs were reduced at 2 to 8 h and ended 4 to 16 h later, which was longer than that of children with early stage shock. The accelerated spontaneous respiratory rate was slowed down by 7 ±4 per minute 4 h later, PO2/FiO2 rose from （ 177.7 ± 53.1 ）mmHg before CBP to （341.0 ± 60. 2 ） mmHg 4 h after CBP in children with respiratory failure and reached the normal value （5.3 ± 2. 1 ） h later. FiO2 declined to less than 50%. Pediatric critical illness score was 62. 2 ± 7.4 on adimission and elevated to （86.6 ± 9. 0 ）24h later, which was a significant elevation as compared to that of children with sepsis who were not treated with CBP seen between Aug. 2001 and July 2003. The survival rate was 72. 7% after CBP and the effective rate of the treatment was 90. 9%, but was 36% in children who were not treated with CVVHDF. Conclusion CBP can effectively improve the vital organ＇s function of children with sepsis and MODS and raise their survial rate. Replacement fluid of modified Ports formula was useful for stability of serum potassium and sodium, but resulted in elevation of serum glucose, calcium, and osmolarity. The application of CBP in children with sepsis can lead to slight drop of blood pressure at the beginning and to bleeding during CBP.