The Value Of Pulse Perfusion Index Combined With The End Of Exhalation Carbon Dioxide In Cardiopulmonary Resuscitation

Objective:ToobservechangesofperfusionindexandP_ETCO₂ during cardiopulmonary resuscitation（CPR）in patients with cardiac arrest（CA）,and to evaluate the CPR quality and prognosis of CA patients,Providing a reliable indicator for quality monitoring during CPR.Methods:From April 2016 to December2017,45cases of adult CA in the Department of emergency medicine in General Hospital Affiliated to Tianjin Medical University were performed CPR in accordance with the 2015 American Heart Association（AHA）Guidelines for CPR and Emergency Cardiovascular Care.PI and P_ETCO₂ were monitored during the implementation of CPR.After CPR,it is divided into ROSC group and no ROSC group according to whether or not it recovers spontaneously.All of the clinical variables of the patients were collected during CPR.At the same time,the average value of PI within 2 minutes after the start of CPR is set as the initial PI value,and the average value of PI within the last 2 minutes before the end of CPR is set as the final PI.The average value of PI from the beginning of CPR to the end is the average.PI.The PI values and P_ETCO₂ values of the two groups at different time periods were compared.Plot the average PI and P_ETCO₂ at different time periods,and combine the two to apply the receiver operating characteristic curve（ROC）curve for ROSC,calculate the area under the ROC curve（AUC）,at lastcalculatethecutoff value.Results:After closed heart cardiopulmonary resuscitation（CCCPR）in 45patients with cardiac arrest,12 returned to spontaneous circulation with a success rate of 26.67%.There was no significant difference in the age and sex between ROSC group and non-ROSC group（P>0.05）.During CPR,he initial PI values in group ROSC were not statistically different between the two groups（P>0.05）.The average PI value and terminal PI value were significantly higher than those in the non ROSC group.The difference was statistically significant[1.295（0.998,2.752）VS0.873（0.453,1.521）,P<0.05;1.821（1.012,3.595）VS 0.257（0.120,0.519）,P<0.001].The initial P_ETCO₂,mean P_ETCO₂ and terminal P_ETCO₂ were higher than those in the non resuscitation group,and the difference was statistically significant[7.000（3.609,14.654）vs 1.800（1.000,7.900）,P<0.05;22.167（11.812,36.338）vs 3.963（2.526,9.010）,P<0.001;29.505（19.838,35.870）VS4.000（2.308,10.250）,P<0.001].The initial P_ETCO₂,mean P_ETCO₂,terminal P_ETCO₂,mean PI,and terminal PI value for predicting the probability of ROSC in patients were（0.747,0.907,0.965,0.705,0.965）under the working characteristic curve of the subjects（AUC）,these best cutoff points were 2.586,8.900,16.12,0.924,and 0.834.The sensitivity,specificity and respectively of the average PI and P_ETCO₂mmHg were 83.30%、91.70%,57.60%、75.80%,68.88%and86.67%.When the two indexes combining to prejudge the ROSC of CA patients,for predicting the probability of ROSC in patients were 0.929 under the working characteristic curve of the subjects（AUC）.The sensitivity of ROSC in the diagnosis of CA patients was 83.30%,the specificity was 93.9%and the diagnostic accuracy was 95.56%.Conclusions:PI can be used as an index to evaluate the quality of CPR and prognosis of CA patients.The application of P_ETCO₂ recommended by PI combined with guidelines is of better predictive value for cardiopulmonary resuscitation.