The Values Of EVLWI And ITBVI For PiCCO Monitoring In Early Fluid Resuscitation In Septic Shock Patients

Objective:To study the volumetric parameters of PiCCO monitoring:EVLWI and ITBVI are more valuable or not in fluid resuscitation in early stage of septic shock patients.Methods and materials:It is a prospective study.Thirty-six septic shock patients who were treated with invasive mechanical ventilation from February 2017 to August 2017in ICU of WU ZHONG People’s Hospital,WU ZHONG county,were enrolled into this study.All the patients were divided into two groups,randomly.One group is the PiCCO monitoring group,the other is the CVP monitoring group.Before conducting fluid resuscitation,all of the patients were inserted a double lumen catheter from their subclavian vein or internal jugular vein.An artery catheter was inserted into the CVP monitoring group’s femoral artery,and so did the PiCCO monitoring group with a PiCCO catheter.The two groups were given volume expansion to meet the CVP monitoring parameters of 8 to 12 mmHg and the PiCCO monitoring parameters of 3 to 7 ml/kg for EVLWI and of 850 to 1000 ml/m² for ITBVI.At the beginning of fluid resuscitation,each patient’s stroke volume（SV）of left ventricular and the maximum diameter of inferior vena cava at end-expiration（Dmax）and minimum diameter at end-inspiration（Dmin）were measured and recorded by a skillful sonographer.The inferior vena cava collapsibility index is calculated by the following formulate:（Dmax-Dmin）/Dmax.After a 500ml of0.9%sodium chloride fluid for injection is challenged within 30 minutes,every patient’s SV as well as the diameters of the inferior vena cava at end-inspiration and at end-expiration were measured again.The fluid responsiveness is defined by SV improved at least 10%after fluid challenge.When each monitoring parameter is maintained but the patient’s mean artery pressure（MAP）below 65mmHg,the norepinephrine will be used to maintain MAP around 70⁷5mmHg.The arterial blood gas analysis was carried out at baseline,at 3 hours and at 6 hours after fluid resuscitation.Urine was recorded in first hour and in one hour at 6 hours after fluid resuscitation.Besides,28 days mortality were calculated.Results:There are no significant differences between the two groups’general data such as age,sex,acute physiology and chronic health evaluationⅡscore（APACHEⅡ）,sequential organ failure assessment（SOFA）,CVP,MAP,lactate acid,artery partial pressure of oxygen（PO₂）and oxygenation index of blood gas analysis,urine output in first hour after fluid resuscitation.The levels of PO₂ and oxygenation index at 6 hours after fluid resuscitation are increased but the level of lactate acid is decreased than that of each group at baseline.There are no significant differences between the two groups about levels of lactate acid and oxygenation index.The partial pressures of oxygen are significantly increased at 6 hours after fluid resuscitation compared to the baseline of each group.And the trend of increasing about artery partial pressure is significantly higher in PiCCO monitoring group than in CVP monitoring group.The levels of CVP are slowly increased while giving fluid resuscitation but there is no significant difference between the two groups.Nine patients have positive fluid responsiveness in PiCCO monitoring group,and seven patients do in CVP monitoring group.There is no significant difference between the two groups on fluid responsiveness.The cutoff value of inferior vena cava collapsibility index to predict fluid responsiveness is 20.5%with a sensitivity of 81.3%and a specificity of 65%,and the area under receiver operating characteristic curve is 0.791.The urine output in one hour at 6 hours after fluid resuscitation is increased than that in first hour each other.There is also a significantly increasing in PiCCO monitoring group than in CVP monitoring group about urine output.In 4 weeks,6 patients in PiCCO monitoring group died and 12 patients died in CVP monitoring group.There is also a significant difference for mortality between the two groups.Conclusions:It is more efficient in improving partial pressure of oxygen,increasing urine output and decreasing lactate acid levels in artery blood gas analysis when conducting fluid resuscitation for septic shock patients following by the volumetric parameters:EVLWI and ITBVI of PiCCO monitoring.PiCCO catheter is easy to be inserted and to be used.It is fitful to be used in ICUs in junior hospitals.