不同复温速率及维持浅低温对家兔肢体爆炸伤合并海水浸泡后电解质及血气的影响

Effects of serum electrolyte and artery blood - gas in rabbits having limb blast injury coupled with hypothermia induced by seawater immersion following rewarming and maintenance of lighthypothermia

]目的观察不同复温速率及浅低温对兔肢体爆炸伤合并海水浸泡后机体电解质及血气的影响。方法复制24只肢体爆炸伤合并海水浸泡致低体温（31．0±0．5）℃成年家兔模型，随机等分为I组复温至（38．04±0．5）℃，复温速率（8．94±0．93）℃／h；Ⅱ组复温至（38．04±0．5）cC，复温速率（3．884±0．22）℃／h；lit组复温至（38．0±0．5）℃，复温速率（2．184±0．12）℃／h；H组复温至（34．0±35．0）℃并维持至实验结束，复温速率（4．494±0．66）oC／h，以调节环境温度及加温输液的方法，将体温恢复目标体温后维持该体温观察6h。于致伤前（1r0）、浸泡降温后（T，）、复温即刻（T2）、复温后3h（T3）、复温后6h（T4）时相点采集颈动脉血，检测Na^＋、K^＋、C1^＋、pH值、BE、HCO；、PaC02和Pa02等。结果电解质K^＋和C1^＋：Ⅱ组在T2（P〈0．05），T，（P〈0．01），T4（P〈0．01）较复温前明显升高。血气分析变化特征：pH值I组T。降低（P〈0．05）；BE：I组、H组在L（P〈0．05），T。（P〈0．05）明显降低；HCO^3-：I组、H组在B、T4明显降低（P〈0．05）；Pa02：I组T3（P〈0．05），T。（P〈0．01）明显降低，Ⅲ组在1r3（P〈0．01），T4（P〈0．05）明显升高，H组在T4明显降低（P〈0．05）；PaC02：II组在T3明显降低（P〈0．01）、Ⅲ组在1r3、T4较复温前明显降低（P〈0．01）和H组在T3（P〈0．05），T4（P〈0．01）较复温前明显降低。Hb：各组T3、T4较复温前明显降低（P〈0．01）。结论在肢体爆炸伤合并海水浸泡致低体温后的早期，快速复温及维持机体的低体温可导致机体酸碱平衡紊乱程度加重，缓慢复温方式（复温速度在2—4℃／h）则可以在早期较好地维持机体对酸碱平衡的代偿性调节作用，给后期的治疗争取时间。各种复温速率及维持机体的低体温状态对该模型下机体的电解质方面的影响差异无统计学意义。

Objective To investigate the effect of different rewarming rates and maintenance of light hypothermia on serum electrolyte and artery blood - gas in rabbits after limb blast injury, coupled with seawater immersion. Methods The model of limb blast injury coupled with seawater immersion was reproduced [ the animals were immersed to low body temperature of （ 31 ＋ 0.5 ℃） ]. 24 adult rabbits were randomly divided into group I [ the rapid rewarming group, n = 6, rewarming to （38 ± 0.5）℃ at a rate of （ 8.94±0.93 ） ℃/h ], group I] [ the rapid rewarming group, n = 6, rewarming to （ 38±0.5 ）℃at a rate of （3.88±0.22）℃/h ] , group ]lI[ the rapid rewarming group, n = 6, rewarming to （38±0.5 ） ℃ at a rate of （2.18 ＋ 0.12）℃/h ], group H [ the hypothermia group, n = 6, rewarming to （34 - 35 ）℃ at a rate of （4.49±0.66）℃/h and kept at that temperature till termination of experiment]. Regulation ofambient temperature and warm transfusion were used to restore body temperature to target levels and maintained there for 6 hours. Blood samples were collected on pre - injury（ To ）, post - immersion（ T1 ）, the time when rewarming started（T2 ） , 3 h after rewarming（T3 ）, 6 h after rewarming（ T4 ）, and Na^, K ^, C1-, pH, BE, HCO3-, PCO2, PO2 were detected. Results K^ and C1- concentrations in the plasma of the animals in group I when （ T2 ） （ P 〈 0.05 ）, （ T3 ） （ P 〈 0.01 ） and（ T4 ） （ P 〈 0.01 ） were significantly higher compared with that of the animals pre - injury, pH of the animals in group I when （T4 ） （P 〈 0.01 ） were decrease. BE of the animals in group I, group H when （ T3 ） （ P 〈 0.01 ） and （ T4 ） （P 〈 0.05 ） were significantly decrease. HCO3- of the animals in group I, group H when （ T3 ） and （ T4 ） were significantly decrease（P 〈 0.05）. PO2 of the animals in group I when （ T3 ） （ P 〈 0.05 ） and （ T4 ） （ P 〈 0.01 ） were significantly decrease, PO2 of the animals in group III when（ T3 ） （ P 〈 0.01 ） and （ T4 ） （ P 〈 0.05 ） were significantly higher, PO2 of the animals in group H when （ T4 ） （P 〈 0.05） were decrease. PCO2 of the animals in group I1 when （ T3 ） （P 〈 0.01 ） were significantly decrease, PCO2 of the animals in group HI when（ T3） and（ T4 ） were significantly decrease（ P 〈 0.01 ）, PCO2 of the animals in group H when（ T3 ） （P 〈 0.05 ） and（ T4 ） （ P 〈 0.01 ） were significantly decrease. Hb of the animals in all of group when（T3）and（T4）were significantly decrease（P〈0.01）. Conclusion Rapid rewarming and hypothermia may lead to the increased of the body acid - base disorders. But slowly rewarming （re- warming velocity 2 -4~C/h） could be better maintain the balance of the body of acid - base decompen- sated adjustment function in early way. And all kinds of rewarming and hypothermia under the influence of the body~ electrolyte no obvious difference in this model state.