Posterior parasagittal in-plane ultrasound-guided infraclavicular brachial plexus block-a case series

Abstract

Background: The brachial plexus at the infraclavicular level runs deeper compared to its course proximally, giving rise to impaired needle visualisation due to the steep angle of needle insertion with the current ultrasound-guided approach. A new posterior parasagittal in-plane ultrasound-guided infraclavicular approach was introduced to improve needle visibility. However no further follow up study was done.

Methods: We performed a case series and a cadaveric dissection to assess its feasibility in a single centre, University of Malaya Medical Centre, Kuala Lumpur, Malaysia from November 2012 to October 2013. After obtaining approval from the Medical Ethics Committee, University Malaya Medical Centre, 18 patients undergoing upper limb surgery were prospectively recruited. A cadaveric dissection was also performed. The endpoints of this study were the success rate, performance time, total anaesthesia-related time, quality of anaesthesia and any incidence of complications.

Results: All patients had 100 % success rate. The imaging time, needling time and performance time were comparable with previously published study. There were no adverse events encountered in this study. The cadaveric dissection revealed a complete spread of methylene blue dye over the brachial plexus.

Conclusion: This study demonstrated that the posterior parasagittal in-plane approach is a feasible and reliable technique with high success rate. Future studies shall compare this technique with the conventional lateral parasagittal in-plane approach.

Trial registration: ClinicalTrials.gov NCT02312453 . Registered on 8 December 2014.

Figures

Fig. 1

Ultrasound guided posterior approach to the infraclavicular brachial plexus. a Parasagittal section through the shoulder medial to the coracoid process showing block needle and ultrasound probe. (With permission from John Wiley and Sons; Ultrasound guided posterior approach to the infraclavicular brachial plexus. Anaesthesia 2007; 62: 539). b Ideal needle insertion point – 2 cm posterior to clavicle to avoid needle contact with the inferior surface of the clavicle

Fig. 2

Proportion of patients with a minimal composite score of 14 points according to time. Most patients achieved readiness to undergo surgery (also defined as block onset time) by 25 min

Fig. 3

Proportion of patients with sensory anaesthesia (score of 2) according to time in the cutaneous distributions of nerves. The musculocutaneous nerve achieved fastest onset of sensory anaesthesia, followed by radial nerve. The ulnar and median nerve tend to be slower in achieving sensory anaesthesia

Fig. 4

Proportion of patients with motor paralysis (score of 2) according to time in distributions of nerves. The musculocutaneous nerve achieved fastest onset of motor paralysis, followed by radial nerve. The ulnar was third and median nerve tend to be the slowest in achieving motor paralysis

Fig. 5

Cadaveric dissection: Ultrasound guided posterior parasagittal in-plane infraclavicular right brachial plexus block (a) needle insertion posterior to clavicle plus injection of dye solution 25 ml normal saline plus 0.2 ml methylene blue, (b) Right brachial plexus; Note the median and ulnar nerves were less stained compared to musculocutaneous and radial nerves (c) needle advancement after passing clavicle, needle trajectory - horizontal, easy direction towards target point, good needle visualization (d) Dye solution deposit on posterolateral aspect of axillary artery, creating double bubble sign

Fig. 6

Ultrasound guided posterior parasagittal in-plane infraclavicular brachial plexus block (a) needle trajectory - horizontal, easy direction towards target point, good needle visualization in most cases (b) LA deposit on posterolateral aspect of axillary artery, creating double bubble sign

Fig. 7

a–e Anatomical variations of the clavicles, (f) the needle head hit against patient’s head, limit the space for the operator to manipulate the needle