Does Anesthetic Technique Affect Pneumatic Tourniquet Pressures in Upper Limb Fracture Surgery?

In pneumatic tourniquet applications, the use of an individualized, lowest-effective tourniquet pressure (TP) has been recommended, in order to avoid pressure related complications. The aim of this study is to compare the effects of general anesthesia and axillary block on arterial occlusion pressure (AOP) estimation based TP settings in upper limb fracture surgery.

After, ethical committee approval 80 adult patients undergoing upper limb fracture surgery who gave their signed informed consent will be included. The age below 18 and above 85 years, American Society of Anesthesiology (ASA) physical status >2, any contraindication to axillary block or GA, adverse reaction history to anesthetic drugs, severe anemia, and refusal to give informed consent will be the exclusion criteria. The patients will be randomized to one of two study groups using a computer-generated randomization list to receive GA (Group 1) and axillary block (Group 2).

Main endpoints are initial and maximal blood pressures, AOP, initial and maximal TPs, and tourniquet time. Additionally, the surgeon will evaluate the quality of bloodless surgical area with respect to the amount of blood using a 4-point scale (1: Excellent= No blood in the surgical field, 2: Good= Some blood in the surgical field but no interference with surgery, 3: Fair= Blood in the surgical field but no significant interference with surgery, 4: Poor= Blood in the surgical field obscures the view) at the beginning, in the middle, and at the end of the surgical procedure. The patients will be observed for signs of tourniquet related complications by a blind investigator. SPSS 20.0 for Windows is used for data analysis. The t test and the χ2 test will be used for continuous and categorical data respectively. A P value below 0.05 will be considered as statistically significant.