Study On Effects Of SvO₂ Oriented Early Goal Directed Therapy On Hemodynamics And Oxygen Dynamic In Pigs With Septic Shock Under Hypothermia

Objective:To investigate the effects of SvO₂ orientated EGDT on hemodynamics and oxygen dynamics in pigs with septic shock at low temperature.Method:36 male Bama pigs,weight range from 18 to 22 kg,randomly divided into normal control group（group N）,low temperature control group（group H）,normal temperature conventional treatment group（group NC）,normal temperature EGDT treatment group（group NE）,low temperature conventional treatment group（group HC）and low temperature EGDT treatment group（group HE）,each group of 6 pigs.After anesthesia induction was maintained anesthesia by isoflurane inhalation.Bilateral femoral arteriovenous puncture and right internal jugular vein which placed floating catheter catheterization.The bladder incision drainage.Corresponding dose of LPS was given for model construction.Group N and group H were given no treatment,group NC and group HC were given traditional recovery therapy in two different temperatures,the group NE and the group HE were given EGDT in two different temperatures after the model was complete successfully.The 1ml internal jugular blood and 1ml arterial blood were collected for blood gas analysis before LPS pumping（T1）,when shock model were established and started treatment（T2）,treatment for 1hour（T3）,2 hour（T4）,3 hour（T5）,4 hour（T6）,5 hour（T7）,6 hour（T8）.The data of detected MAP,CVP,CO,SVRI,SvO₂,DO2,VO2,Ca-v O2,urine volume,total liquidvolume,jejunum dry wet ratio of each group were drawn graphs using Excel.SPSS19.0 statistical software was used for statistical analysis,measurement data were expressed as（mean ± standard deviation）（X ±s）,the difference among groups was compared by two independent samples t test,P<0.05.manifested statistical significance.Result1.The general situation The weight,length and building the model of infusion LPS of each group of experimental animals had no statistical significance（P>0.05）,the urine output of group N is less than that in the group H,mortality rate is lower than that in low temperature control group,core temperature from T4 is higher than that in low temperature control group（P<0.05）;The urine output of group NC was less than that of group NE,and liquid intake more than group NE,and the core temperature from T6 below group NE（P<0.05）,there was no statistically significant difference between the group NC and group NE about the mortality rate（P>0.05）;Group HC’s urine output is less than that in the group HE,liquid intake more than that in group HE,core temperature from T6 below group HE（P<0.05）,there was no statistically significant difference between the group HC and group HE about the mortality rate（P>0.05）;The normal temperature EGDT’s urine output was more than that in low temperature EGDT group,liquid intake was less than that in the low temperature EGDT group,mortality rate was lower than that in low temperature EGDT group,the core temperature from T4 was higher than that in low temperature EGDT group（P<0.05）.2.The hemodynamic changes2.1 MAP The MAP of normal temperature control in T5^T8 is higher than that of low temperature control;group normal temperature EGDT at T3 T8 show no significant difference with group normal routine treatment group（P>0.05）;group low temperature EGDT at T3 T8 show no significant difference with group low routine treatment temperature（P>0.05）;The MAP at T2^T5,low temperature group was obviouslyhigher than that of normal temperature group（P<0.05）.The MAP at T5^T8,low temperature group was obviously lower than that in normal temperature group（P<0.05）.2.2 MPAP The MPAP of normal temperature control in T4^T8 is higher than that of low temperature control;group normal temperature EGDT at T3 T8 show no significant difference with group normal routine treatment group（P>0.05）;group low temperature EGDT at T3 T8 show no significant difference with group low routine treatment temperature（P>0.05）;EGDT group under normal temperature were lower than that of low temperature EGDT group in T2-T8 point（P<0.05）.2.3 CO The CO of normal temperature control in T2^T4 is lower than that of low temperature control,and higher than it in T5^T8;group normal temperature EGDT at T3 T8 show no significant difference with group normal routine treatment group（P>0.05）;group low temperature EGDT at T3 T8 show no significant difference with group low routine treatment temperature（P>0.05）;The CO at T2^T5,low temperature group was obviously higher than that of normal temperature group（P<0.05）.The CO at T5^T8,low temperature group was obviously lower than that in normal temperature group（P<0.05）.2.4 CVP The CVP of normal temperature control in T2^T8 show no significant difference with low temperature control;group normal temperature EGDT at T3 T8 show no significant difference with group normal routine treatment group（P>0.05）;group low temperature EGDT at T3 T8 show no significant difference with group low routine treatment temperature（P>0.05）;The CVP at T2^T4,low temperature group was lower than that of normal temperature group（P<0.05）.The CO at T5^T8,low temperature group was higher than that in normal temperature group（P<0.05）.2.5 SVRI The SVRI of normal temperature control in T2^T4 is lower than that of lowtemperature control,and higher than it in T5^T8;group normal temperature EGDT at T3 T8 show no significant difference with group normal routine treatment group（P>0.05）;group low temperature EGDT at T3 T8 show no significant difference with group low routine treatment temperature（P>0.05）;The SVRI at T2^T5,low temperature group was obviously higher than that of normal temperature group（P<0.05）.The SVRI at T5^T8,low temperature group was obviously lower than that in normal temperature group（P<0.05）.3.oxygen dynamic change3.1 SvO₂ The SvO₂ of normal temperature control in T2^T4 is higher than that of low temperature control,and lower than it in T5^T8;group normal temperature EGDT at T3 T8 show no significant difference with group normal routine treatment group（P>0.05）;group low temperature EGDT at T3 T8 show no significant difference with group low routine treatment temperature（P>0.05）;The SvO₂ at T2^T4,low temperature group was lower than that of normal temperature group（P<0.05）.The SvO₂ at T5^T8,low temperature group was higher than that in normal temperature group（P<0.05）.3.2 Ca-v O2,DO2,VO2 At T2⁴ time points,the DO2 of each group decreased,but there was no statistically significant difference in all（P>0.05）,at the same time,Ca-v O2 and VO2 had a statistically significant difference（P<0.05）,and VO2 of normal temperature group is lower than that of low temperature group,Ca-v O2 of normal temperature group is higher than that of low temperature group.Oxygen consumption of normal temperature group is less than that of low temperature group.At T5^T8,the DO2 of control group all declined,which of group normal routine treatment and group normal temperature EGDT began to rise after T6,and the DO2 of low temperature group all decreased（P<0.05）;At T5^T8,the Ca-v O2 and DO2 of normal and low temperature groups all declined,normal temperature control was higher than the low temperature control,group normal routine treatment was lower than the group normal temperature EGDT,group low routine treatment temperature was lower than the group low temperature EGDT,group normal temperature EGDT was higher than the group low temperature EGDT,the difference was statistically significant（P<0.05）.3.3 O2 ER The O2 ER of normal temperature control in T5^T8 is higher than that of low temperature control;group normal temperature EGDT at T3^T8 show no significant difference with group normal routine treatment（P>0.05）;group low temperature EGDT at T3^T8 show no significant difference with group low routine treatment temperature（P>0.05）;The O2 ER at T2^T4,low temperature group show no significant difference with normal temperature group（P<0.05）.The O2 ER at T5^T8,low temperature group was obviously lower than that in normal temperature group（P<0.05）.3.4 LA The LA of normal temperature control in T2^T8 show no significant difference with low temperature control;group normal temperature EGDT at T3^T8 show no significant difference with group normal routine treatment（P>0.05）;group low temperature EGDT at T3^T8 show no significant difference with group low routine treatment temperature（P>0.05）;The LA at T2^T4,low temperature group was obviously lower than that in normal temperature group（P<0.05）.The LA at T5^T8,low temperature group was obviously higher than that in normal temperature group（P<0.05）.4.the histology detection Specimens of recovery after treatment for 6h,group normal temperature EGDT’s jejunum dry wet ratio was lower than that of the group normal routine treatment,which of group low temperature EGDT is lower than that of the group low routine treatment,group normal temperature EGDT’s was obviously lower than group group low temperature EGDT’s,differences were statistically significant（p<0.05）.Conclusion:1.The hemodynamics and oxygen dynamics of early septic shock at low temperature isin a state of compensatory,characterized by cardiac output increased,peripheral vascular resistance decreased,tissue oxygen delivery and oxygen consumption increased,no changes in lactic acid and oxygen uptake rate.2.The hemodynamics and oxygen dynamics of middle-late septic shock at low temperature is in a state of decompensatory,characterized by cardiac output decreased,peripheral vascular resistance decreased obviously,tissue oxygen delivery,oxygen consumption and oxygen uptake rate decreased,lactic acid increased.The models’ circulatory failure and oxygen metabolic disorder obviously.3.SvO₂ oriented EGDT of early septic shock at low temperature environment can effectively stabilize hemodynamics and oxygen dynamics,which can effectively improve cardiac output,peripheral vascular resistance and tissue perfusion status,and oxygen supply and demand balance maintain well.But it’s very difficult to maintain hemodynamics and oxygen dynamics stability for a long time at low temperature environment,characterized by cardiac output decreased,peripheral vascular resistance decreased obviously,tissue oxygen delivery,oxygen consumption and oxygen uptake rate decreased,lactic acid increased,and with the extension of low temperature time these gradually increased.4.SvO₂ oriented EGDT of middle-late septic shock at low temperature environment can’t effectively stabilize hemodynamics and oxygen dynamics,which is useless for septic shock treatment.