Impact of Local Anesthetic Volume During Ultrasound-guided Stellate Ganglion Block

Impact of Local Anesthetic Volume on Temperature Increase in the Upper Extremity During Ultrasound-guided Stellate Ganglion Block: A Prospective Randomized and Comparative Clinical Trial

The purpose of this study was to compare the temperature changes of the upper extremities when using local anesthetic of various volume (4ml, 6ml, 8ml) in the ultrasound guided stellate ganglion block.

One pain physician performs all US-guided stellate ganglion block(SGB)s, who is not involved in evaluating study variables. Electrocardiography, noninvasive blood pressure, heart rate, and peripheral oxygen saturation were monitored for all patients before, while, and after conducting procedure.

For US-guided SGB, patients are supine positioned, and skin preparation on injection site is done with chlorohexidine. Procedure is conducted under ultrasound guidance at C6 level. 4ml, 6ml, and 8ml of 1% lidocaine is injected for the each group, respectively. Syringes are prepared by one nurse who do not involved in other steps of this study.

Temperature measurement is conducted 4 times (before US-guided SGB and after 10, 20, and 30m from SGB) at both hands, face, axillar by one person who's not involved in other measuring in the study.

Inclusion Criteria:

• Patients aged 18 to 85 years
• Patients with a new or known diagnosis of chronic neuropathic pain at the upper extremity or face.

Exclusion Criteria:

• Refusal of a patient
• Any vascular disease in the upper extremities (or face)
• Previous history of thoracic sympathetic or stellate ganglion neurolysis (e.g. thermocoagulation, radiofrequency neuromodulation, and/or chemical neurolysis)
• Coagulopathy
• Systemic infection or local infection at the needle injection site
• Major deformation at the level of the neck (radiotherapy, surgery, etc.)
• Concomitant chronic pain syndrome at other sites.
• Post-pneumonectomy on the controlateral side
• Known allergy to local anesthetics of amide type
• Inability to understand a numeric rating pain scale (cognitive dysfunction)