用容量动力学分析犬失血性休克时琥珀明胶和乳酸钠林格氏溶液的扩容效力

 目的 应用容量动力学和物质守恒定律动态分析犬失血性休克时乳酸林格氏溶液（lactated Ringer’s solution，LR）和琥珀明胶（gelatin）的扩容效力，为临床液体复苏提供理论依据。方法 犬20只，每只犬实验2次，每次实验间隔1周，随机分成4组：CL组（n=10），麻醉后输LR液；CG组（n=10），麻醉后输琥珀明胶溶液；BL组（n=10），失血性休克后再输LR液；BG组（n=10），失血性休克后再输琥珀明胶溶液。CL、BL组输注30 mL/kg LR，CG、BG组输注10 mL/kg琥珀明胶，30 min内输完。BL、BG组先经动脉放血，使MAP下降30%并维持60 min，然后分别输注LR 30 mL/kg、Gelatin 10 mL/kg。各组液体均为恒速输注，并持续30 min。开始输液时及以后每5 min直到研究结束均测定血红蛋白（Hb）及红细胞压积（Hct）、尿量及血流动力学参数。应用物质守恒定律和容量动力学理论分析得到以下参数：容量增加、外周容量增加、容量扩张效率、靶容量（V）、中央室靶容量（V₁）、周边室靶容量（V₂）、清除率（Kr）、转移系数（Kt）。结果 CG、BL、BG组的V、Kr显著小于 CL组， BL组的V₁、Kr、Kt、尿量显著低于CL组（P<0.05）。BL、BG、CG组在输液结束时的容量增加显著大于CL组，BG、CG组容量扩张效力显著大于BL、CL组，BL组容量扩张效力又显著大于CL组（P<0.05）。结论 容量动力学分析表明失血性休克时乳酸林格氏溶液和琥珀明胶的扩容效力增加，乳酸林格氏溶液扩容效力增加更为显著。

Comparison of gelatin and loctated Ringer's solution on the efficacy of volume expansion during hemorrhagic shock in dogs by volume kinetics

Objective To compare the time course of distribution and elimination of gelatin and lactated Ringer's solution (LR) by volume kinetics and mass balance analysis during hemorrhagic shock in dogs, and try to design and optimize fluid therapy in a more scientific manner. Methods Twenty dogs were randomly divided into 4 groups: CL group, CG group, BL group, and BG group. Each animal was subjected to two randomly ordered experiments that separated for at least 1 week. In the first phase, plasma volume expansion was studied in the state of anesthesia, animals received 30 mL/kg of LR (CL group) or 10 mL/kg of gelatin (CG group) over 30 min. In the second phase, plasma volume expansion was studied in the state of hemorrhagic shock, animals received 30 mL/kg of LR (BL group) or 10 mL/kg of gelatin (BG group) over 30 min. Hb concentration and Hct were measured every 5 min during and after infusion for 90 min. Hemodynamic parameters were recorded at the same time. The distribution and elimination of infused fluid were studied by volume kinetics, based on serial analysis of hemoglobin dilution in arterial blood, and by mass balance that incorporated volume calculations derived from volume kinetic analysis and measurements of urinary volumes. Results When a one-volume kinetic model was fitted to the data, the value of V and Kr in CG, BL, and BG group were significantly smaller than those in CL group (P<0.05), which could be found from the computer-generated curves.When a two-volume kinetic model was fitted to the data, the value of V1, Kr, Kt in BL group were significantly smaller than those in CL group (P<0.05). The calculations based on mass balance corresponded to the predicted based on volume kinetics. The change of central volume (CCV) in BL, BG, and CG group was significantly greater than those in CL group (P<0.05). The VEE in BG and CG group was significantly higher than that in BL and CL group. The value of VEE in BL group was significantly higher than that in CL group (P<0.05). Conclusions Both of the efficacy of lactated Ringer's solution and gelatin increased significantly in the state of hemorrhagic shock, and the former increased more.