Ultrasound-Guided Thoracic Paravertebral Block: The Direction of Local Anaesthetic Spread

Abstract

Chest wall trauma following motor vehicle accident can lead to prolonged ventilator support with subsequent pulmonary complications and delayed weaning off the mechanical ventilation. Patients with multiple rib fractures usually present with severe pain which impairs their respiratory mechanics. There are different methods of pain relief for patients with rib fractures. In this report, we present a case of rib fractures where pain was treated successfully with continuous local anaesthetic infusion using ultrasound guided thoracic paravertebral block (TPVB). A 28-year-old male was brought to Accident and Emergency department. The patient was resuscitated and as he was irritable and presented with poor GCS (Glasgow coma scale) score, so the trachea was intubated and he was put on mechanical ventilator. Following failed multiple attempts to wean off from the ventilator mainly due to patient getting restless coupled with desaturations at each attempt the insertion of TPVB catheter with continuous bupivacaine infusion to facilitate weaning off ventilator process was planned. Under ultrasound (US) guidance, a catheter was placed at D5-6 vertebrae level. It was noticed that most of the local anaesthetics (mixed with Omnipaque dye) spreaded towards caudal than the cephalad direction. Continuous infusion of bupivacaine 0.25%, 4-6 ml/hour was started to provide pain relief. The trachea was extubated on 5th post-admission day in SICU. In conclusion, continuous local anaesthetic infusion via US guided TPVB catheter technique proved very effective in pain relief following multiple rib fractures. Also in contrary to other reports, we have noticed more caudal than cephalad spread of the TPVB injectate.