Ultrasonographic Guidance in Placing a Catheter for Continuous Axillary Brachial Plexus Block

Abstract

To the Editor: For performing regional anesthesia to make surgical interventions possible, and for continuous analgesia management, brachial plexus block can be applied through the axillary approach [1]. Even though the technique for single-dose application is quite simple [2], the placement of the catheter in the axillary sheath to ensure continuous anesthesia and analgesia is difficult and has a high failure rate [3]. Therefore, different techniques are proposed [4,5]. We have utilized sonography (color Doppler sonograph) for tracing large arteries and veins and for inserting the catheter into the axillary sheath. A 21-yr-old male was hospitalized for a pollicization operation on his left hand. He was a good candidate for insertion of an axillary sheath catheter and brachial plexus block for peroperative anesthesia and postoperative analgesia. Informed consent was obtained from the patient before performing the procedure. The left axillary region of the patient was properly exposed in the supine position. After local anesthesia under standard sterile conditions, the axillary artery and vein were detected and localized in a horizontal section image obtained by the sonography unit (ACUSON 128 XP). For this purpose, a 7.5-mHz linear transducer covered with a sterile drape was used. (The skin was moistened to slide ethyl alcohol onto it.) Sloping the probe distally up to 45 degrees, a Contiplex cannula (18-gauge, 1 3/4 in., O 1.2 times 45 mm Contiplex Registered Trademark Katheterset; B. Braun, Germany) was inserted through the anesthesized skin parallel to the probe, and its tip was pointing to the proximal axilla. The needle catheter was then pushed forward along the anterior arterial wall with the guidance of a sonographic image Figure 1. Our location was confirmed via sagittal image by rotating the probe. While holding the plastic part of the cannula at this site, the metalic needle was withdrawn and instead a catheter (O 0.45 times 0.85 mm, 40-cm Contiplex Registered Trademark Katheterset) previously filled with contrast material (1/4 contrast, 3/4 normal saline) was inserted into the cannula. While holding the catheter in place and removing the plastic cannula, an image was obtained by the Siemens Digitron 2 digital substraction angiography unit. Through an intravenous cannula inserted from the ipsilateral antecubital region, 3 mL dilute radiocontrast was injected to see the relation of the catheter to the axillary vein. After blood flow washed away the injected intravenous contrast material, 5 mL dilute radiocontrast was reinjected from the axillary catheter to show the axillary sheath Figure 2. After connecting an antibacterial filter to the catheter, it was fastened in a sterile manner onto the skin, and the patient was taken to the operating room. After routine monitoring in this way, 0.5% bupivacaine, 20 mL, was administered. Twenty-five minutes after this application, a complete sensory and motor block occurred. Surgical intervention was performed successfully and without pain.Figure 1: The needle of the cannula is between artery and vein. Horizontal sonogram is shown. a, Artery; v, vein; arrow points to the top of the needle.Figure 2: The catheter in the axillary sheath. (Axillary sheath is visible by means of radiopaque material.)Postoperative analgesia was required approximately 5 h after perioperative local anesthetic injections, and a mixture of 0.5% bupivacaine, 2 mL; fentanil, 1 mL; and 0.9% normal saline, 7 mL, was administered through the axillary catheter. The effect of this lasted for another 5.5 h. The procedure was then repeated when necessary. With the help of this newly presented procedure, brachial plexus block via the axillary route is easier to perform, and a high success rate may be expected (except in cases of anatomic deformities). Although digital substraction angiography was utilized in our study to probe the efficacy of the procedure, ordinary sonographic imaging will be enough for successful results. Among continuous brachial plexus block applications via the axillary route, we suggest this procedure for surgical anesthesia and continuous long-term analgesia, since it is easy to perform, safe, inexpensive, and has no adverse effects. M. Erdal Guzeldemir, MD* Bahri Ustunsoz, MD dagger Departments of *Anesthesia and dagger Radiology, GATA Medical Faculty, Ankara, Turkey