Introduction

The axillary approach to anaesthetising the brachial plexus has been used for over half a century(1). Since the perivascular approach was described, it has gained popularity and is used for operative anaesthesia, emer-gency room manipulations and for pain free upper limb physiotherapy(2-4). Recent techniques have been devel-oped using ultrasound and nerve stimulators to increase the accuracy of the technique(5, 6). These facilities are not widely available in resource limited settings. We de-scribe a perivascular technique that can be used in re-source limited areas. This will acquaint surgeons who have previously used only general anaesthesia for hand surgery with a technique that has served well for many years even in places without ultrasound and nerve stim-ulators. We aim to describe the technique and showcase its use in a number of hand surgical cases.

 

Methods

The method of achieving anaesthesia is described. The patient lies supine with the arm abducted and externally rotated to expose the axilla. The axillary artery is palpat-ed in the axilla and marked with a marker pen. The skin of the axillary area is prepared with alcohol mixed with iodine. The surgeon dons sterile gloves and palpates for the axillary artery guided by the mark previously made. A gauge 25 needle is introduced adjacent to the pulsa-tions of the artery. Vascular penetration is indicated by blood flowing back through the needle. Should this happen, the needle is repositioned as to have the needle adjacent to the artery in the axillary sheath. This will be evidenced by a pulsatile needle without any blood flow-ing back. The chosen local anaesthetic is then instilled through the needle. The surgeon aspirates every 5mls to ensure the needle is not in a vessel. Correct needle placement in the axillary sheath is confirmed by a char-acteristic resistance to the instillation of the local anaes-thetic and by back flow of local anaesthetic through the needle when the syringe is removed. A tourniquet may be used after the first 20mls have been instilled to ensure proximal flow of the anaesthetic in the sheath ensuring a more profound block. Take of the block is assessed by evaluating the motor and sensory functions of the nerves of the upper limb.

 

We reviewed details of nine patients who underwent hand surgery under the regional block described at the Mulago Hospital. We excluded patients under the age of 12 years. The regional block was administered by the surgeon and intraoperative monitoring by an anaesthetic officer. The delay in onset of anaesthesia was determined

 

​

 

as the time from instillation of anaesthetic drug to com-plete anaesthesia of the surgical site. The duration of surgery was measured from skin incision to skin closure and dressing. In cases of failure of the regional block, the patient was put under general anaesthesia by the anaesthetic officer. An axillary block was determined as successful if the entire surgery was conducted under the block without need for supplementation or conversion to either general surgery or the tumescent technique. Pa-tients in whom there was no take were operated either under general anaesthesia or the tumescent technique.

 

 

The data on age, procedure, delay and duration of sur-gery was inputted into a computer and analysis conduct-ed using Microsoft Excel software.

 

Results

 

Six of the nine patients undergoing ten procedures were males (Table 1). The median age of the patients was 25years (Range 12-27 years). The procedures included tendon repairs, carpectomies and fixation for hand frac-tures (table 1). The block was successful in 7 patients giv-ing a success rate of 77.8%. In all cases the drug used was Mepivacaine 1% with an average dosage and volume of 333.3mg and 33.3millilitres respectively. The two cases in this study that failed were due to failure to palpate the artery in one and the use of a wide needle in the other. The average delay in onset was 20 minutes (Range 14-

 

1. while the average duration of surgery was 99 min-utes (Range 55-180)

 

Discussion

 

The reported rates of success with the perivascular ax-illary block technique have varied from centre to cen-tre, although generally high (7). A study in Germany reported a success rate of 72% without the use of ul-trasound while in Croatia they were able to report suc-cessful anaesthesia in 85% of patients(8, 9) Our success rate closely matches this but we are confident that the success rate will improve with subsequent patients. Suc-cess rates as high as 98% have been described and are achievable(10).

 

The technique described has fewer complications than other techniques used for upper limb surgery. Of note is the risk of pneumothorax which does not occur with this technique but has been reported with the supracla-vicular approach (7). It seems that with the use of ul-trasound and nerve stimulators, this risk is somewhat

​

 

Click to view table 1

 

 

reduced(11). These facilities are however not available in resource poor settings. It is hence safer to use the peri-vascular technique.

 

 

There is a risk of intravascular injection with this peri-vascular technique and this has been touted as one of the advantages for the use of ultrasound . However it has been found that this is not the case and intravascular in-jection may still occur despite the use of ultrasound(12). This technique has the advantage that it can be used even in areas where the anaesthesia provider is not con-versant with the technique as the surgeon will adminis-ter the block and eave the intraoperative monitoring to the anaesthetic provider.

 

Conclusion

 

The described perivascular technique is reliable and safe and can be used in areas with limited resources.

 

References

 

1. Burnham BJ. Regional block of great nerves of the upper arm. Anesthesiology 1958;19:281.

2. Aksoy SM, Izdes S, Komurcu M, et al. Utilization of axillary brachial plexus block in the postoperative rehabilitation of intra-articular fractures of the distal humerus. Acta Orthop Traumatol Turc.2010: 44(2):111-6.

3. Winnie AP, Collins VJ. The subclavian perivascular technique of brachial plexus anaesthesia. Anesthesiology 1964;25:353-63.

4. Mackay CA, Bowden DF. Axillary brachial plexus block--an underused technique in the accident and emergency depart-ment. J Accid Emerg Med. 1997 Jul;14(4):226-9.

5. Conceicao DB, Helayel PE, Oliveira Filho GR. [A compara-tive study between ultrasound and neurostimulation guided axillary brachial plexus block]. Rev Bras Anestesiol. 2009 Sep-Oct;59(5):585-91.

6. O'Donnell BD, Ryan H, O'Sullivan O, Iohom G. Ultrasound-guided axillary brachial plexus block with 20 milliliters local anesthetic mixture versus general anesthesia for upper limb trauma surgery: an observer-blinded, prospective, random-ized, controlled trial. Anesth Analg. 2009 Jul;109(1):279-83

 

 

1. Hamelberg W, Dysart R, Bosomworth P. Perivascular axillary versus supraclavicular brachial plexus block and general an-esthesia. Anesth Analg. 1962 Jan-Feb;41:85-90.

2. Pfeiffer K, Weiss O, Krodel U, Hurtienne N, Kloss J, Heuser D. [Ultrasound-guided perivascular axillary brachial plexus block. A simple, effective and efficient procedure]. Anaesthe-sist. 2008 Jul;57(7):670-6.

3. Smigovec E, Tripkovic B, Sulentic M, Smigovec I, Milavec D, Bukvic Mokos Z. Regional anesthesia for upper extrem-ity surgery--our experience. Acta Dermatovenerol Croat. 2008;16(1):8-12.

4. Mortazavi MT, Niazi-Ghazani M, Ansari M. Brachial plexus blockade in elbow, arm or hand surgeries. Pak J Biol Sci. 2009 Oct 15;12(20):1353-8.

5. Niemi TT, Salmela L, Aromaa U, Poyhia R, Rosenberg PH. Single-injection brachial plexus anesthesia for arteriovenous fistula surgery of the forearm: a comparison of infraclavicular coracoid and axillary approach. Reg Anesth Pain Med. 2007 Jan-Feb;32(1):55-9.

6. Robards C, Clendenen S, Greengrass R. Intravascular injection during ultrasound-guided axillary block: negative aspiration can be misleading. Anesth Analg. 2008 Nov;107(5):1754-5.