USG Imaging of Brachial Plexus Sheath & Its Fascial Compartments at Costoclavicular Space & Infraclavicular Fossa
Condition: Musculoskeletal Diseases or Conditions
MeSH terms: Musculoskeletal Diseases
Study type: Observational

Summary: 
      The existence of the brachial plexus sheath (BPS) and its septae and compartments has been a
      subject of debate and controversy. Numerous cadaver studies indicate that BPS is present
      while other researchers based on limited clinical data suggest none. Nevertheless, cumulative
      evidence over the last six decades indicate that it is multi-layered, fibrous and a web-like
      connective tissue that is derived from the deep cervical fascia and fused with the deep
      fascia of the arm The BPS completely envelopes that neurovascular bundle and filed with loose
      connective tissue and fat. It is a multi-compartment structure in the axilla with each nerve
      having a separate compartment, that communicate with each other. Some studies suggested that
      the septae affect the spread of local anesthetic during an axillary or infraclavicular
      brachial plexus block, while some suggest the opposite. With the use of ultrasound imaging,
      researchers found the presence of this connective tissue septum within the BPS at the
      costoclavicular space and infraclavicular fossa. The septum is visualized as a linear
      hyperechoic band on ultrasound imaging and when present appears to reduce the spread of the
      drugs during brachial plexus block. Yet the anatomy is poorly seen with the previous
      generation of ultrasound imaging. The aim of this study is to define the connective tissue
      (fascial) layers that surround the brachial plexus and its septum at the infraclavicular
      fossa by reviewing our archived high definition ultrasound images of 100 patients who had
      successfully undergone the ultrasound guided brachial plexus block over a 5 year period (2013
      to 2018).
    

Detailed description: 
      This is a retrospective study reviewing archived high definition ultrasound images as
      multiple short video loops (6 seconds) in avi format from 100 adult patients who had
      undergone ultrasound guided costoclavicular brachial plexus block for surgical anesthesia for
      their upper limb surgery over a 5 year period, from April 2013 to April 2018 by three
      experienced anesthesiologists. Demographics data such as age, gender, body mass index, ASA
      Physical Classification System, local anesthetic drug used and mode of anesthesia can be
      retrieved from patients' record or Clinical Management System. No direct contact nor
      intervention will be done to the patients in this study, so waiver of patient informed
      consent has been sought. There will be no patients' data in any of the ultrasound images as
      the ultrasound video loops for the costoclavicular brachial plexus block are routinely saved
      anonymously for all patients. All information related to the patients will be kept
      confidential and they will not be identified in any form in future publications.
    

Intervention name(s): Ultrasound guided Costoclavicular Brachial Plexus Block
Intervention type(s): Procedure
Intervention description(s): Ultrasound images from patients scheduled for upper limb surgery under costoclavicular brachial plexus block (one kind of regional anesthesia) have been routinely collected at our institute. These images will be reviewed.
Observational model: Case-Only
Time perspective: Retrospective
Sampling method: Non-Probability Sample
Study population: 
        100 adult patients who had undergone ultrasound guided costoclavicular brachial plexus
        block for surgical anesthesia during forearm or hand surgery over a 5 year period, from
        April 2013 to April 2018.