Supraclavicular Block vs Retroclavicular Block: Incidence of Phrenic Nerve Paralysis

Ultrasound Guided Supraclavicular Brachial Plexus Block vs Retroclavicular Brachial Plexus Block: Comparison of Impact on Ipsilateral Diaphragmatic Function

The aim of this study is to evaluate differences between ultrasound guided supraclavicular versus retroclavicular brachial plexus blocks: two similar brachial plexus nerve block techniques that differ in their needle trajectory and injection site.

To date, there has not been a study that has compared clinically the retroclavicular brachial plexus block to the supraclavicular brachial plexus block or other brachial plexus blocks. The aim of this study is to evaluate differences between ultrasound guided supraclavicular versus retroclavicular brachial plexus blocks, with primary focus on the incidence of diminished ipsilateral hemidiaphramatic excursion (ipsilateral phrenic nerve blockade). We will also evaluate differences between the two techniques in the success of producing surgical anesthesia, procedural time to perform the block (including imaging time and needling time), block onset time, ease of quality ultrasound needle visualization, and incidence of paresthesias, vascular puncture and pneumothorax. Lastly, we will observe and compare the distribution of motor and sensory blockade of the two techniques

Retroclavicular, Supraclavicular, Diagphram, hemiparesis, nerve block, regional anesthesia, anesthesiology

Patients in this group will be randomized to receive an Ultrasound Guided Supraclavicular Brachial Plexus Nerve Block and outcomes will be measured over the perioperative and 1day time period.

Patients in this group will be randomized to receive an Ultrasound Guided Retroclavicular Brachial Plexus Nerve Block and outcomes will be measured over the perioperative and 1day time period.

An ultrasound-guided supraclavicular or retroclavicular nerve block with 30 ml of 0.5% ropivicaine will be performed on patients scheduled for lower arm surgery; 25 ml to be delivered to the brachial plexus and 5 ml to the intercostal nerve

Ultrasonographic block imaging times (time between ultrasound probe placement on the patient and satisfactory image of target anatomy acquisition. needling time (time between needle insertion into the skin and the end of local anesthetic injection through the block needle), onset and duration of sensory block, and proceduralist's rating of ease of block performance will be measured.

Inclusion Criteria: patients scheduled for lower arm surgery patients aged 18 years or older patients ASA class I-III Exclusion Criteria: Patients unable to cooperate or consent to the study pre-existing neuropathy significant pulmonary disease contralateral phrenic nerve or diaphragmatic dysfunction allergy to local anesthetics infection at needle insertion site history of coagulopathy BMI > 40 kg/m2

Georgiadis PL, Vlassakov KV, Patton ME, Lirk PB, Janfaza DR, Zeballos JL, Quaye AN, Patel V, Schreiber KL. Ultrasound-guided supraclavicular vs. retroclavicular block of the brachial plexus: comparison of ipsilateral diaphragmatic function: A randomised clinical trial. Eur J Anaesthesiol. 2021 Jan;38(1):64-72. doi: 10.1097/EJA.0000000000001305.