Objective: Brachial plexus block is an anesthetic technique commonly used in upper extremity surgical procedures. Both blood flow increase and vasodilatation occur in ipsilateral upper extremity because of brachial plexus blocks (BPB). There are no enough data related with ipsilateral arterial diameter-blood flow changes in different local anesthetic volumes.
Method: Thirty healthy volunteer adult patients who were scheduled for elective hand surgery had an ultrasound-guided axillary BPB (ABPB) for anesthesia. Baseline regional hemodynamic parameters were measured in ipsilateral axillary artery using PWD US. Patients were divided into 3 groups as group 20, 30 and 40 according to using local anesthetic volumes. Diameter, flow velocity measurements were performed with PWD in artery before block (pre-block),10 minutes after block and 60 minutes after block.
Results: The earliest change after the BPB in all groups was a change to a monophasic from triphasic morphology in the PWD spectral waveform for axillary artery. In axillary measurements, There was significant increase PSV, EDV, Vmean between pre-block and post-block10 in group 30 and 40 (p<0.05) and there was also significant decrease PSV, EDV, Vmean, TAMV between post-block and post-block60 in group 30 and 40 (p<0.05).
Conclusion: To our knowledge, this is the first report that demonstrates the earliest regional hemodynamic change after ABPB in different volumes. In the groups that were given the volumes above 20 ml arterial restrictive narrowing was evident. The findings of this study support the use of ABPB with low volume local anesthetics aiming to minimize probable pathologic hemodynamic changes.