Study On Optimal Strategy Of Perfusion Index For Fluid Resuscitation In Septic Shock

Objective:To investigate the differences between targeting perfusion index during fluid resuscitation in septic shock and targeting conventional parameters,and to compare the differences in macrocirculatory and microcirculatory hemodynamic parameters,negative fluid balance time,ICU mortality and 28-day mortality under different resuscitation strategies.Method:Forty patients with septic shock were included and randomly divided into Pi guided therapy group and conventional guided therapy group,with 20 cases in each group.Pulse-indicated continuous cardiac output and perfusion index monitoring were performed later.One-hour bundle therapy was performed according to the guidelines,and resuscitation was targeted according to the following parameters:MAP≥65 mm Hg,CVP 8-12 mm Hg,Sv O₂≥65%or Scv O₂≥70%,and urine output>0.5 m L/（kg.h）.After reaching the target in the conventional group,no further intervention was performed.On the basis of the conventional group,the perfusion index was continuously monitored to guide resuscitation and maintain Pi>1.4 as the goal.Hemodynamic parameters,including heart rate,mean arterial pressure,central venous pressure,blood lactate,central venous oxygen saturation,venous partial pressure of carbon dioxide difference,negative fluid balance time,ICU mortality and 28-day mortality,were collected from all patients at different time points（0 h,6 h,24 h,and 48 h）during resuscitation,and P<0.05 was considered statistically significant.Result:After fluid resuscitation treatment in the two groups,comparing different time and different indicators,the blood lactate level at 6h,24h and 48h in the Pi group was lower than that in the conventional group（P<0.05）;the negative fluid balance time in the microcirculation group（[2.7,（2.0,3.0）]d）was earlier than that in conventional group（[3.4,（2.5,4.0）]d）（P<0.05）;while the CVP,Pcv-a CO₂,Scv O₂,CO,HR and MAP were not significantly different at each time point（P>0.05）;the ICU mortality[20%vs.45%（X²=2.85,P=0.09）]and 28-day mortality[50%vs.70%（X²=1.67,P=0.19）]in the Pi group were lower than those in the conventional group,but the difference had no statistical significance.Conclusion:In this study,the use of macrocirculatory hemodynamic parameters,combined with microcirculatory parameters Pi to guide fluid resuscitation,can improve hemodynamic parameters and reduce lactate levels faster.At the same time,it can shorten the time of negative fluid balance and guide volume management,which provides a new idea for better fluid resuscitation in septic shock.