Study On The Value Of Pcv-aCO₂、Pcv-aCO₂/Ca-cvO₂ Combined With Lactate In Evaluating The Severity And Prognosis Of Patients With Septic Shock

Objective To investigate the value of Pcv-aCO₂,Pcv-aCO₂/Ca-cvO₂and their combination with lactic acid respectively in the severity and prognosis of patients septic shock.Methods Adopting prospective and observational research methods,selected from October 2018 to December 2020 to be admitted to the Intensive Care Unit（ICU）of the General Hospital of Ningxia Medical University patients with septic shock,diagnostic criteria with reference to the 2018 China sepsis/septic shock emergency diagnosis and treatment guidelines and reference the overseas related research,septic shock patients were divided into group A:Pcv-aCO₂/Ca-cvO₂≤1.8 and Pcv-aCO₂≤6mm Hg;Group B:Pcv-aCO₂/Ca-cvO₂≤1.8 and Pcv-aCO₂>6mm Hg;Group C:Pcv-aCO₂/Ca-cvO₂>1.8 and Pcv-aCO₂≤6mm Hg;Group D:Pcv-aCO₂/Ca-cvO₂>1.8 and Pcv-aCO₂>6mm Hg.After the patients with septic shock were admitted to ICU,their age,gender,underlying disease,site of infection,average hourly dosage of norepinephrine,central venous pressure（CVP,measured three times a day,averaged）,daily fluid inflow and other data were recorded.File.usd10.00 routine blood,liver and kidney function,electrolyte,arterial blood gas analysis,record into the SOFA score 24hours a day,APACHE Ⅱ score,synchronization to return center venous blood gas and peripheral arterial blood gas,blood gas analyzer were used to detect the Pcv-aCO₂,Ca-cvO₂,ScvO₂,p H value,PaCO₂,lactate,SaO₂,BE value,all patients with artery and peripheral venous blood gas analysis and determination of 8 hours,all the values and the mean of the three as the data,Blood gas analysis data of central vein and peripheral artery in patients with septic shock were recorded dynamically at 1,2,3,and 5 days after ICU admission.All patients with septic shock were followed up for 28 days,and were divided into survival group（58 cases）and death group（32 cases）according to survival status.Results 1.Among the 90 patients with septic shock,58 cases survived and 32 cases died,with a fatality rate of 35.6%at 28 days.The main infection sites were abdominal cavity infection（56.7%）and pulmonary infection（27.8%）.2.Group A（Pcv-aCO₂/Ca-CvO₂≤1.8and Pcv-aCO₂≤6mm Hg）had the shortest ICU hospitalization time,and the difference was statistically significant（all P<0.05）.3.SOFA score,APACHE Ⅱ score and average hourly dosage of norepinephrine in the survival group of septic shock patients were lower than those in the death group（all P<0.05）.4.On the first day after admission to ICU,ScvO₂in group B was the lowest,while ScvO₂in group C and D was no different from that in group A,or even higher than that in group A.On the 2nd,3rd and 5th day in ICU,group B was lower than group A,while there was no difference between group C and group D and group A at the same time point,but the intra-group dynamic comparison began to decrease on the 3rd day in ICU（all P<0.05）.5.There was no significant difference in lactate level between the four groups on the 1st,2nd,3rd and 5th day after the admission to ICU（all P≥0.05）.After admission to ICU,lactate levels in all the four groups were decreased,and group A and group C were the earliest to decrease,and the levels were decreased on the second day after admission to ICU（all P<0.05）.The lactate in group B and group D began to decrease on the 3rd day of admission to ICU（both P<0.05）.6.On the first day after admission to ICU,Pcv-aCO₂in group B and D was higher than that in group A and C,but there was no significant difference in Pcv-aCO₂levels on the second,third and fifth day after admission to ICU（all P>0.05）.The level of Pcv-aCO₂in group B remained high on the 2nd,3rd and 5th day after admission to ICU.The level of Pcv-aCO₂in group A and group C increased on the second day after admission to ICU,and lasted until the fifth day（all P<0.05）.There was no significant difference in Pcv-aCO₂value within group B（P≥0.05）.There was a downward trend in group D,but still a continuous increase（all P<0.05）.7.After the four groups of septic shock patients were admitted to ICU,the level of Pcv-aCO₂/Ca-cvO₂in group C and group D was higher than that in group A and group B on the first day of admission（all P<0.05）,but there was no difference in the level of Pcv-aCO₂/Ca-cvO₂among the four groups on the second,third and fifth day of admission to ICU（all P>0.05）.The Pcv-aCO₂/Ca-CvO₂value of group A began to increase on the 2nd day in ICU and lasted until the 3rd day（all P<0.05）.The P_CV-aCO₂/Ca-CvO₂value of group D began to decrease on the 5th day in ICU,but the level was still high（P<0.05）.There was no significant difference in Pcv-aCO₂/Ca-cvO₂value in group B and group C（all P>0.05）.8.ScvO₂of the death group was lower than that of the survival group on the second and third days in ICU,with statistical significance（P<0.05）.The lactate in the death group was higher than that in the survival group on the 1st,2nd and3rd day in ICU,and the difference was statistically significant（P<0.05）.Pcv-aCO₂in the death group was significantly higher than that in the survival group on the 2nd and 3rd day of ICU admission,with statistical significance（P<0.05）.There was no significant difference between survival group and death group in Pcv-aCO₂/Ca-cvO₂at the 1st,2nd,3rd and 5th day in ICU（all P>0.05）.There were no significant differences in ScvO₂,serum lactate and Pcv-aCO₂between the survival group and the death group on the 5th day of ICU（all P≥0.05）.9.ScvO₂in the death group began to decrease from the second day in ICU and continued to the third day,with statistical significance（all P<0.05）;The lactate value in the death group began to decline on the third day after admission to ICU,and the difference was statistically significant（P<0.05）.The lactate value in the survival group began to decline on the second day,and the lactate value was less than 2 mmol/L on the third day（all P<0.05）.Pcv-aCO₂in death group began to increase on day 3,and the difference was statistically significant（P<0.05）.There was no significant difference in Pcv-aCO₂/Ca-cvO₂value between survival group and death group（all P>0.05）.10.There was a negative correlation between Pcv-aCO₂/Ca-cvO₂on the first day of admission to ICU and the average p H value on the first day of admission（r=-0.283,P=0.007）.There was a negative correlation between Pcv-aCO₂/Ca-cvO₂and the average p H value of the patients on the second day in ICU（r=-0.260,P=0.016）.Pcv-aCO₂on day 2 was positively correlated with fluid intake on day 2（r=0.259,P=0.016）.11.On the third day,Pcv-aCO₂combined with Apache Ⅱ score had the largest area under the ROC curve.Conclusion 1.Pcv-aCO₂and Pcv-aCO₂/Ca-_CvO₂combined with lactate have a certain predictive value on the severity of septic shock patients.2.APACHE Ⅱ score combined with Pcv-aCO₂has greater prognostic value in the evaluation of patients with septic shock.