Lazzaro Spallanzani, an 18th century Italian biologist, is credited with the discovery of ultrasound, which he coined ‘echolocation’. [1] Little may he have realized then that his revelation would transform into an all pervading technology in modern science. Though La Grange and colleagues, in 1978, were the first to employ ultrasonic blood flow detector to locate insertion point for the supraclavicular brachial plexus block, ultrasound guidance in real time motion was first utilized by S. Kapral et al for the same block in a series of forty patients in 1994, thus, heralding a fresh epoch in regional anaesthesia. [2, 3] As is often the case with the introduction of new technologies, ultrasound guidance was also met with cynicism and disdainful resistance. However, not much later, ultrasound guidance was being hailed as the ‘gold standard’ for regional anaesthesia, and it was proclaimed that the search for the elusive ‘holy grail’ had ended. [4]
Among the first nerve/plexus blocks to find wider acceptance with the adoption of ultrasound guidance was the supraclavicular brachial plexus block. The fear of arterial puncture and accidental pneumothorax magically seemed to vanish into thin air. Correlation between clinical and sono-anatomy led to a better understanding of interscalene, infraclavicular and axillary approaches to the brachial plexus. [5] Lower limb blocks began to witness a renaissance due to the widespread prescription of antiplatelet drugs as part of preventive cardiology. Though deeper to the skin in comparison to the upper limb, ultrasound guidance improved identification of neural structures.
It was reported in literature that ultrasound improves patient comfort, block acceptance, onset of block, quality of block, permits the injection of lower local anaesthetic volumes, and thereby, the potential for LAST, and reduces the incidence of certain complications that may be attributed to the block procedure. [6] However, given the resolution of current port
Effect of different volumes of 0.375% ropivacaine on diaphragmatic paralysis by supraclavicular brachial plexus block under ultrasound guidance
