Stroke Volume Variation And Pulse Pressure Variation In Predicting Fluid Responsiveness In Ageing People

Objective To investigate the difference of accuracy and thresholds of the strokevolume variation and pulse pressure variation between ageing and young andmiddle-aged people in predicting fluid responsiveness.Methods Sixty-three patients undergoing elective gastrointestinal surgy were enclosedin this study.They were divided into2groups:the ageing group(age≥65, n=33) and theadult group (18≤age≤55, n=30). Induction of anesthesia was performed withdormicum(0.05mg· kg-1),propofol(1-2mg· kg-1)and fentanily(3μg· kg-1), andorotracheal intubation was facilitated with rocuronium(0.6mg·kg-1). Anesthesia wasmaintained with continous infusions of propofol in order to keep a Bispectral Index(Aspect1000, Aspect Medical Systems, Natick, MA) between40and60. All patients’lungs were ventilated in a volume of10ml/kg of body weight at a frequency of8-12cycles/min. Following anesthesia induction, PPV and SVV was continuously displayed.Other haemodynamic data (CI、SVV、MAP、HR、CVP) were also recorded.All of thedata should be recorded before and after volume expansion(VE)(Hetastar6%,7ml/kg).Fluid responsiveness was defined as an increase in CI≥15%(△CI≥15).Draw thereceive operating characteristic curve(ROC) of SVV and PPV of the two groupsrespectively.ResultsSVV and PPV were significantly decreased in the responders after after volumeexpansion in both group.The SVV threshold value of the aging and adult group that responsed to volumeexpansion was10.5%(sensitivity99.3%, specificity71.8%) and10.5%(sensitivity80.0%, specificity80.0%), respectively.The PPV threshold value of the aging and adult group that responsed to volumeexpansion was9.5%(sensitivity86.7%, specificity70.8%) and10.5%(sensitivity90.0%, specificity82.0%), respectively.The area under roc curve（AUC）of SVV in the aging and adult group was0.747and0.885, respectively.The AUC of PPV in the two groups was0.737and0.890, respectively.Conclusion SVV and PPV were demonstrated to be sensitive and specific predictors offluid responsiveness in ageing patients in mechanically ventilated under generalanaesthesia.The accuracy of PPV and SVV of the adult group in predicting fluidresponsiveness was higher than the ageing group.