A Randomised Trial Comparing Supraclavicular Block vs Supraclavicular and Pecs II Block in Arteriovenous Grafting

A Randomised Trial Comparing Supraclavicular Block vs Supraclavicular and Pecs II Block in Arteriovenous Grafting

A Randomised Controlled Trial Comparing Ultrasound-guided Supraclavicular Brachial Plexus Block With Combined Supraclavicular and Pecs II Block in Patients Undergoing Arteriovenous Grafting Surgery

This study evaluates the addition of Pecs II block to ultrasound-guided supraclavicular brachial plexus block in patients undergoing arteriovenous graft creation surgery. Participants will be randomised into two equal groups, one receiving supraclavicular and pecs II blocks, the other receiving supraclavicular block and sham block (Grade 1).

Regional anaesthesia (RA) for arteriovenous grafting surgery has advantages of avoiding risks of general anaesthesia (GA) in this group of patients with significant co-morbidities, and beneficial vasodilatation, which may prevent early fistula thrombosis. Hence, RA is preferable to GA for this surgery. Brachial plexus blocks (BPB) are the most commonly employed RA technique to anaesthetise the upper limb for this surgery. According to the results of a recent 2-year retrospective audit in our centre, ultrasound-guided supraclavicular BPB are the most popular RA technique for this surgery. Anatomically, the T1 and T2 dermatomes are often missed by the supraclavicular BPB. This means that the upper medial arm and axilla (sites involved in brachiobasilic and brachioaxillary arteriovenous grafting) may not be adequately anaesthetised, mandating intraoperative local anaesthetic supplementation by the surgeon. This may affect patients' and surgeons' acceptance of, and satisfaction with the RA technique. The ultrasound-guided Pecs II block, described by Blanco et al, seems to address this problem, as the intercostal T1-6, intercostobrachialis, long thoracic nerves and nerve to serratus anterior are targeted by this block.

brachio-axillary, brachio-basilic, interfascial plane block, Pecs II block, supraclavicular brachial plexus block

Ultrasound-guided supraclavicular brachial plexus block with Ropivacaine 0.5% 20ml and Pecs II block with Ropivacaine 0.5% 10ml.

Sham block -- with skin preparation, ultrasound scanning of pecs II block area, but no actual needle injection

Whether there was a need for the surgeon to infiltrate a standardised local anaesthetic drug (0.5% ropivacaine) to the operative site during surgery

Whether there was a need for additional sedation or systemic analgesia (on top of what is specified in the protocol)

Duration of time from administration of the block(s) to when patient first requests for oral analgesia. Participants will be followed up for 24 hours after surgery.

Inclusion Criteria: Patients scheduled for arteriovenous grafting under regional anaesthesia in Changi General Hospital American Society of Anaesthesiologists (ASA) physical status 3 to 4 Elective or emergency surgery Exclusion Criteria: Patients unable to give consent, unable to communicate or cooperate with simple instructions Patients with regular consumption of strong opioids (eg. morphine, oxycodone) or steroids Patients with allergy or contraindications to local anaesthetics or any of the drugs included in this study Patients with pre-existing upper limb neurological deficits Patients who refuse or are unsuitable for regional anaesthesia (eg. severely coagulopathic)

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Arab SA, Alharbi MK, Nada EM, Alrefai DA, Mowafi HA. Ultrasound-guided supraclavicular brachial plexus block: single versus triple injection technique for upper limb arteriovenous access surgery. Anesth Analg. 2014 May;118(5):1120-5. doi: 10.1213/ANE.0000000000000155.

Reynolds TS, Kim KM, Dukkipati R, Nguyen TH, Julka I, Kakazu C, Tokhner V, Chauvapun JP. Pre-operative regional block anesthesia enhances operative strategy for arteriovenous fistula creation. J Vasc Access. 2011 Oct-Dec;12(4):336-40. doi: 10.5301/JVA.2011.8827.

Sahin L, Gul R, Mizrak A, Deniz H, Sahin M, Koruk S, Cesur M, Goksu S. Ultrasound-guided infraclavicular brachial plexus block enhances postoperative blood flow in arteriovenous fistulas. J Vasc Surg. 2011 Sep;54(3):749-53. doi: 10.1016/j.jvs.2010.12.045. Epub 2011 Mar 2.

Purcell N, Wu D. Novel use of the PECS II block for upper limb fistula surgery. Anaesthesia. 2014 Nov;69(11):1294. doi: 10.1111/anae.12876. No abstract available.

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