The substantial impact of ultrasound-guided regional anaesthesia on the clinical practice of peripheral nerve blocks

Background. Ultrasound-guided (US-guided) regional anaesthesia has gained worldwide popularity in recent years owing to the benefits the method offers to patients. The 1st Department of Anaesthesiology and Intensive Care of Warsaw Medical University was one of the first centres in Poland to employ US-guided peripheral nerve blocks (PNB) on a routine basis. The technique was incorporated into the institution's clinical practice from 2007. The purpose of this study was to retrospectively assess changes in the clinical practice of US-guided versus non US-guided PNBs over six years of experience with the technique. Methods: Retrospective analysis assessing the prevalence of PNB methods, local anaesthetic (LA) injection techniques (i.e. single injection vs. multiple), LA volumes used, success rates and the incidence of complications. Results: This study included 4,066 PNBs performed between January 2006 and June 2012. The results showed systematic growth in the prevalence of US-guided blocks in the total number of PNBs, from 8.6% in 2007 up to 53.3% in 2012. The mean LA volume used in PNB was significantly lower in US-guided blocks compared to traditional PNB techniques (respectively, 21.83 mL vs. 31.41 mL, P < 0.05) without a decrease in the success rate (respectively, 76% vs. 74%, P > 0.05). A shift in the prevailing block technique from single injection to multiple injections was observed, regardless of the nerve location technique employed (from 29% up to 84% of PNBs performed using multiple injection technique). Conclusions: The use of ultrasound optimizes the technique of peripheral blocks and the amount of local anaesthetic used. Ultrasonography does not affect the safety of peripheral blocks.