Comparative of the Effectiveness of Different Objective Method for Infraclavicular Brachial Plexus Block Success; Which One of Them is A Reliable and Early Indicator?

ABSTRACT BACKGROUND Traditional methods that evaluate the success of peripheral nerve block have been replaced by methods that allow objective evaluations over time. Multiple objective techniques for peripheral nerve block have been discussed in the literature. OBJECTIVE This study aims to investigate whether perfusion index (PI), non-invasive tissue hemoglobin monitoring (SpHb), tissue oxygen saturation (StO 2 ), tissue hemoglobin index (THI) and body temperature are reliable and objective methods to evaluate the adequacy of infraclavicular blockage. DESIGN A prospective observational study. SETTING Single center, Department of Anesthesiology, Harran University Medical Faculty, Turkey, from February 2019 to December 2019. PATIENTS A total of 100 patients scheduled to undergo forearm surgery. INTERVENTION Ultrasound-guided infraclavicular block (ICB) in 100 patients undergoing forearm surgery. MAIN OUTCOME MEASURES PI, SpHb, StO 2 , THI and Body Temperature measurements were recorded 5 min before the block procedure, right after the procedure, and until the 25th minute after the procedure at 5-min intervals. These values were compared between the blocked limbs and non-blocked limbs while being statistically compared between the successful and failed block groups. RESULTS Although there were significant differences between the groups of blocked extremity and non-blocked extremity in terms of StO 2 (P = 0.001), THI (P = 0.001), PI (P = 0.001) and body temperature (P = 0.001), there was no significant difference between these groups in terms of SpHb (P > 0.05). Moreover, a significant difference was detected between the groups of successful block and failed block in terms of StO 2 (P = 0.002), PI (P = 0.002) and body temperature (P = 0.005), while there was no significant difference between these groups in terms of THI (P > 0.05) and SpHb (P > 0.05). CONCLUSION StO 2 , PI and body temperature measurements are the simple, objective, noninvasive techniques to be used to evaluate success of block procedures. According to The receiver operating characteristic (ROC) analysis, StO 2 is the specific parameter with the highest sensitivity among these parameters. TRIAL REGISTRATION ACTRN12621000588897