Two approaches to the axillary brachial plexus

A new technique of cannulation of the axillary neurovascular sheath, using loss of resistance to saline, was evaluated and compared to the established technique of eliciting paraesthesiae with a short-bevelled needle. The cannulation technique produced a more reliable block of axillary, musculocutaneous and radial nerves, significantly fewer incomplete blocks and a lower incidence of accidental vessel puncture.     

The effects of clonidine on ropivacaine 0.75% in axillary perivascular brachial plexus block

INTRODUCTION: The new long-acting local anesthetic ropivacaine is a chemical congener of bupivacaine and mepivacaine. The admixture of clonidine to local anesthetics in peripheral nerve block has been reported to result in a prolonged block. The aim of the present study was to evaluate the effects of clonidine added to ropivacaine on onset, duration and quality of brachial plexus block. METHODS: Patients were randomly allocated into two groups. In group I brachial plexus was performed using 40 ml of ropivacaine 0.75% plus 1 ml of NaCL 0.9%, and in group II brachial plexus was performed using 40 ml of ropivacaine 0.75% plus 1 ml (0.150 mg) of clonidine. Onset of sensory and motor block of radial, ulnar, median and musculocutaneous nerve were recorded. Motor block was evaluated by quantification of muscle force, according to a rating scale from 6 (normal contraction force) to 0 (complete paralysis). Sensory block was evaluated by testing response to a pinprick in the associated innervation areas. Finally, the duration of the sensory block was registered. Data were expressed in mean+/-SD. For statistical analysis a Student t-test was used. A P-value of < or = 0.05 was considered as statistically significant. RESULTS: The duration of blockade was without significant difference between the groups. Group I: 718+/-90 min; Group II: 727+/-117 min. There was no intergroup difference in sensory and motor onset or in quality of blockade. CONCLUSION: The addition of clonidine to ropivacaine 0.75% does not lead to any advantage of block of the brachial plexus when compared with pure ropivacaine 0.75%.     

Comparison of transarterial and multiple nerve stimulation techniques for axillary block using a high dose of mepivacaine with adrenaline

BACKGROUND: High-dose transarterial (TA) technique results in high effectiveness of the axillary block. The technique is fast and simple, but does not produce a satisfactory success rate when using the manufacturer's recommended dose of mepivacaine. The multiple nerve stimulation (MNS) technique requires more time and experience. This double-blind study compared effectiveness, safety and the time used to obtain an effective analgesia in 101 patients, having an axillary block by either TA or MNS techniques. METHODS: Mepivacaine with adrenaline (MEPA), 850 mg, was used for the initial block. Five millilitres of 1% solution was injected subcutaneously. In the TA group, 20 mL of 2% solution was injected deep to, and 20 mL superficial to the axillary artery. In the MNS group, four terminal motor nerves were electrolocated in the axilla, and injected with 10 mL each. Analgesia was assessed every 10 min and, when needed, supplemented after 30 min. The block was effective when analgesia was present in all sensory nerve areas distal to the elbow. RESULTS: The MNS group required median 11 min for block performance compared with 8 min for the TA group (P < 0.001). Latency of the initial block was shorter and the frequency of supplemental analgesia lower in the MNS group (median 10 min and 6%) than in the TA group (30 min and 36%, respectively), P < 0.001. All incomplete blocks were successfully supplemented. However, the total time to obtain an effective block was shorter in the MNS group (23 min) than in the TA group (37 min), P < 0.001. Two patients in each group had signs and symptoms of systemic toxicity, the most serious being atrial fibrillation and temporary loss of consciousness in a cardiovascularly medicated patient. The local adverse effects (intravascular injections and haematomas) were fewer in the MNS group, P < 0.001. CONCLUSION: The MNS technique of axillary block by four injections of 10 mL of 2% MEPA produces faster and more extensive block than the TA technique by two injections of 20 mL. Therefore, the MNS technique requires fewer supplementary blocks and results in faster patient readiness for surgery. However, high doses of MEPA may result in dangerous systemic toxic reactions.     

A comparison of the vertical infraclavicular and axillary approaches for brachial plexus anaesthesia

BACKGROUND: This prospective, randomized study compared the efficacy of the vertical infraclavicular and axillary approaches using a single injection blockade of the brachial plexus. The primary endpoint was complete blockade in dermatomes C5-Th1, while secondary endpoints included onset time, motor block, block performance time, surgical success rate, patient satisfaction, and side-effects/complications. METHODS: Sixty patients, American Society of Anesthesiologists physical status I or II, scheduled for surgery of the forearm or hand received either a vertical infraclavicular (n = 30) or an axillary block (n = 30). A single injection of 0.5 ml/kg ropivacaine 7.5 mg/ml was made after electrolocalization of nerve fibres corresponding to the median nerve at maximum 0.5 mA (2 Hz, 0.1 ms). Onset and distribution of analgesia and motor block were assessed at 5, 10, 15, 20, 30 and 60 min after the local anaesthetic injection. A complete block was defined as analgesia in all dermatomes (C5-Th1) at 60 min post-injection. RESULTS: The vertical infraclavicular approach provided complete blockade in 29 patients (97%) and the axillary approach in 23 patients (77%). Analgesia in C5-C6 dermatomes and corresponding motor block occurred significantly more frequently in the vertical infraclavicular approach, which also had the shortest onset time. Block procedure was quicker in the axillary approach. Side-effects were similar in both groups, and there were no permanent sequelae. Patient satisfaction was equally high in both groups. CONCLUSION: The vertical infraclavicular approach provides a more complete block than the axillary approach when using a single injection technique and equal volumes/doses of local anaesthetic.     

Fentanyl does not improve the nerve block characteristics of axillary brachial plexus anaesthesia performed with ropivacaine

BACKGROUND: The aim of this prospective, randomized, double-blind study was to evaluate the effects of adding 1 microg. kg-1 fentanyl to ropivacaine 7.5 mg. ml-1 for axillary brachial plexus anaesthesia. METHODS: With Ethics Committee approval and written consent, 30 ASA physical status I-II in-patients, scheduled for orthopaedic hand procedures were randomly allocated to receive axillary brachial plexus block with 20 ml of either ropivacaine 7.5 mg. ml-1 (n=15) or ropivacaine 7.5 mg. ml-1+1 microg. ml-1 fentanyl (n=15). Nerve blocks were placed using a nerve stimulator with the multiple injection technique. A blinded observer recorded the time to onset of surgical block (loss of pinprick sensation in the innervation areas of the hand (C6-C8) with concomitant inability to flex the wrist against gravity and move the fingers when squeezing the hand) and first request for pain medication after surgery. RESULTS: No differences in demography, degree of sedation or peripheral oxygen saturation were observed between the two groups. Median (range) time required to achieve readiness for surgery was 15 min (5-36 min) with ropivacaine alone and 15 min (5-40 min) with the ropivacaine-fentanyl mixture. No differences in the intraoperative quality of nerve block were reported between the two groups. Four patients receiving ropivacaine plain and two patients receiving the ropivacaine-fentanyl mixture did not require analgesics during the first 24 h after surgery (P=0.62). The degree of pain experienced at first analgesic request in those patients asking for pain medication, as well as median consumption of postoperative analgesics, were similar in the two groups. First postoperative analgesic request was made at 11 h (25th-75th percentiles: 9.1-14 h) in patients receiving ropivacaine alone and at 11.8 h (25th-75th percentiles: 9.8-15 h) in patients receiving the ropivacaine-fentanyl mixture (P=0.99). CONCLUSION: The addition of fentanyl 1 microg. ml-1 to ropivacaine 7.5 mg. ml-1 does not improve the nerve block characteristics of axillary brachial plexus anaesthesia for orthopaedic procedures involving the hand.     

Two instances of central nervous system toxicity in the same patient following repeated ropivacaine-induced brachial plexus block

We describe two instances of central nervous system (CNS) toxicity in the same patient following repeated brachial plexus blocks induced by high doses of ropivacaine (6 mg x kg(-1) and 4.5 mg x kg(-1), respectively). Although very high total and free plasma concentrations of ropivacaine were found up to 98 min after induction of the blocks, no signs of cardiovascular toxicity apart from hypertension and sinus tachycardia were observed. The measured plasma concentrations are the highest so far reported in the literature. We conclude that this case demonstrates the high cardiovascular safety level of ropivacaine. These high doses, however, resulted in severe toxic CNS symptoms. Therefore, it is stressed that the dose in relation to the weight of the patient must be calculated when administering a large volume of local anesthetic.     

A comparison of three methods of axillary brachial plexus anaesthesia

One hundred patients scheduled for elective outpatient hand surgery had blockade of the axillary brachial plexus by one of three techniques; insertion of a catheter into the brachial plexus sheath (n = 25), use of paraesthesia (n = 50) or use of the nerve stimulator (n = 25) to localise the plexus. Only two patients required general anaesthesia for the planned surgery. Assessment of the dermatomes blocked did not demonstrate a statistical difference between the success rates of the three groups. The more nerves detected in the paraesthesia and the nerve stimulator groups before injection of local anaesthetic the higher the success rate of the block. We advocate use of the nerve stimulator technique in view of the possible risk of neurological damage associated with paraesthesia and the technical difficulties with the catheter technique, for routine brachial plexus blockade.     

A comparison of lignocaine with prilocaine in axillary brachial plexus anaesthesia

Twenty patients received either lignocaine 1.5% with 1/200,000 adrenaline (group L), or prilocaine 1.5% plain (group P) as a brachial plexus block for surgery to the upper limb, in a randomised double-blind study. The two groups were comparable in age, weight and duration of surgery and there were no significant differences between the two groups with regard to onset, pattern or degree of sensory loss. The degree of motor loss was also comparable. The group L patients had a statistically significant longer duration of sensory loss than those in group P. All the blocks were performed using the same technique and provided complete surgical anaesthesia. Prilocaine 1.5% plain provides adequate sensory and motor blockade for brachial plexus anaesthesia and is a suitable agent for medium duration surgery to the upper limb.     

Lateral infraclavicular plexus block vs. axillary block for hand and forearm surgery

BACKGROUND: In the last few years infraclavicular plexus block has become a method of increasing interest. However, this block has been associated with high complication incidences and without advantage in the quality of blockade over the axillary approach. We prospectively studied 40 patients (ASA I-III) undergoing surgery of the forearm and hand, and investigated the performance of the lateral infraclavicular plexus block against an axillary paravascular block to evaluate the success rate as well as the extent and quality of blockade. METHODS: Patients were randomized into two groups: group I (lateral infraclavicular approach; n=20) and group A (axillary approach; n=20). The lateral infraclavicular approach is a technique with the coracoid process (CP) as landmark. Alone the sagittal plane, the needle is inserted until contact with the CP. The needle is then withdrawn 2-3 mm and reinserted directly under the CP, until it contacts the brachial plexus sheath. Plexus blockade was performed using 40 ml of mepivacaine 1%. Quality of sensory and motor block was recorded selectively for each nerve distribution at close intervals for 6 h. RESULTS: Successful block according to Vester-Andersen's criteria was achieved in 100% of group I and 85% of group A. In group I, a pronounced sensory and motor blockade of the musculocutaneous nerve was observed, while patients of group A had a weak block of this nerve. In group I, an additional spectrum of nerves (thoracodorsal, axillary and medial brachial cutaneous nerves) was involved compared to group A. There was no difference among groups in onset and duration of block. CONCLUSION: Based on the safe landmark and feasibility of this procedure and the additional spectrum of nerve block achieved, the application of lateral infraclavicular technique has to be reconsidered in clinical practice.     

Comparison of 0.2% ropivacaine and 0.25% bupivacaine for axillary brachial plexus blocks in paediatric hand surgery

BACKGROUND: The purpose of this study was to compare the use of ropivacaine 0.2% with bupivacaine 0.25% for axillary brachial plexus block in children undergoing hand surgery. METHODS: In a double-blind, randomized study, 35 children undergoing hand surgery received axillary brachial plexus blocks with 0.5 ml.kg-1 of either 0.2% ropivacaine or 0.25% bupivacaine. Pain scores were noted at 0, 3, 6, 12 and 24 h after surgery. The time to first dose of codeine phosphate and the total doses of all analgesics given were recorded. RESULTS: There was no significant difference between the two groups in pain scores, the time to first dose of codeine phosphate or in analgesic requirements in the first 24 h. CONCLUSIONS: Ropivacaine 0.2% is as effective as bupivacaine 0.25% for axillary brachial plexus blocks in children undergoing hand surgery.     

Fatal streptococcal necrotizing fasciitis as a complication of axillary brachial plexus block

A 74-yr-old diabetic woman developed necrotizing fasciitis ofthe right upper limb after axillary brachial plexus block forcarpal tunnel decompression. Clinical signs included oedema,diffuse swelling and bullae; rapidly followed by toxic shocksyndrome and multiorgan failure. The patient died 48 h afterhospital admission, despite broad-spectrum antibiotics, surgicaltreatment and supportive measures for the management of shockand multiorgan failure. Cultures yielded group A Streptococcus.Delay in antibiotic and surgical treatment probably affectedthe outcome. Early diagnosis and treatment are essential toimprove the outcome of streptococcal necrotizing fasciitis. Br J Anaesth 2004; 92: 427–9     

Clonidine does not improve quality of ropivacaine axillary brachial plexus block in children

Background: The addition of clonidine to peripheral nerve blocks is controversial in children. Objective: The aim of our study was to evaluate the effect of clonidine added to ropivacaine in pediatric axillary brachial plexus block (ABPB). Methods: Children aged 1–6 years, scheduled to undergo forearm or hand surgery, were recruited into this prospective, double‐blind controlled trial. Patients were randomly allocated to receive an ABPB either with ropivacaine 0.2% 0.4 ml·kg^?1 plus saline in 1 ml (RS) or ropivacaine 0.2% 0.4 ml·kg^?1 plus clonidine 1 μg·kg^?1 in 1 ml (RC). Primary endpoints were quality of postoperative analgesia as assessed by pain scores and total 24‐h postoperative analgesia requirements. Secondary outcomes were time to first analgesia request and duration of motor blockade. Results: Sixty patients were recruited (n = 30 per group) into the study. Pain scores were comparable throughout the first 24 h between the two groups. Ten children in the (RS) and six in (RC) groups required supplementary analgesia during the first 24 h (P = 0.24). Children who required further analgesia did so after 288 ± 94 min in the (RS) and 437 ± 204 min in the (RC) group (P = 0.06). There was no difference in the duration of motor block [186 ± 71 and 154 ± 56 min, P = 0.12 for (RS) and (RC), respectively]. Conclusion: Ropivacaine (0.2% 0.4 ml·kg^?1) for ABPB provides sufficient postoperative analgesia in children scheduled for forearm or hand surgery. The addition of clonidine to ABPB does not improve overall postoperative analgesia but may increase the time to first analgesia request.     

Quality of axillary brachial plexus block

A perivascular catheter technique (PVT) and a nerve stimulator technique (NST) for axillary brachial plexus block were compared in terms of quality: complete, incomplete or failed blocks. In a randomised series, 30 PVT blocks and 30 NST blocks were performed by three staff anaesthetists. In the NST group, surgical anaesthesia was always achieved, whereas in the PVT group, four blocks required supplementation with general anaesthesia. In both groups eight patients needed supplementation with additional conduction blocks of 1-3 peripheral nerves. It is concluded that a nerve stimulator technique may increase the success rate of axillary brachial plexus block to some extent.     

Efficacy of vertical infraclavicular plexus block vs. modified axillary plexus block: a prospective, randomized, observer-blinded study

BACKGROUND: Despite containing severe risks, infraclavicular approaches to the brachial plexus gained increasing popularity. Likewise, the vertical infraclavicular plexus block improved anesthesia compared to the standard axillary approach but contains the risk of pneumothorax. Therefore we modified the standard axillary technique by inserting a proximal directed catheter, referred to as a high axillary plexus block. We prospectively compared quality and onset of neural blockade after vertical infraclavicular plexus block (VIP) and high axillary plexus block (HAP) in two randomized groups (30 patients in each). METHODS: In group VIP the insulated needle was inserted midway between the ventral process of the acromion and the jugular notch. In group HAP, first an axillary needle was placed. Through this a stimulating catheter was inserted in a proximal direction (10-15 cm); correct placement was confirmed by nerve stimulation. All patients received 40 ml ropivacaine 0.75% (300 mg). Discriminating between analgesia and anesthesia, a blinded observer assessed progression of neural blockade every 5 min for 60 min by pin prick. Incomplete blocks were supplemented 60 min after initial injection. RESULTS: All patients in both groups demonstrated sufficient surgical anesthesia. No patient needed systemic supplementation or general anesthesia. However, vertical infraclavicular plexus block indicated superior anesthesia compared to high axillary plexus block, regarding musculocutaneous, axillary and radial nerve, which were completely blocked with a higher success rate and in a shorter time interval (P < 0.05). CONCLUSIONS: While both techniques provide sufficient surgical anesthesia, vertical infraclavicular plexus block demonstrated a partially higher success rate and a faster onset than high axillary plexus block.     

Cumulation of bupivacaine, desbutylbupivacaine and 4-hydroxybupivacaine during and after continuous interscalene brachial plexus block

Desbutylbupivacaine (DBB) and 4-hydroxybupivacaine (4-OHB) are major metabolites of bupivacaine. They may cumulate during continuous infusion blocks. In the present study, all patients received an interscalene brachial plexus block with 20-28 ml of 0.75% bupivacaine plus adrenaline. A catheter was introduced into the interscalene space, and an infusion of 0.25% bupivacaine (5-9 ml/h) was started and continued with ten patients for 24 h and with another ten for 48 h. An infiltration block of the suprascapular and intercostobrachial nerves was performed using 0.5% bupivacaine. Before surgery, light general anaesthesia was induced. For measurement of plasma concentrations of bupivacaine, DBB and 4-OHB blood samples were taken before the block and 30 min, 3 h, 24 h and 48 h after the blocks as well as 30 min, 1 h, 2 h, 4 h and 6 h after the termination of the infusions. The highest plasma concentrations of bupivacaine, mean 1.84 micrograms/ml, were measured 30 min after the block. There was a slight but statistically significant rise in the bupivacaine concentrations between 24 and 48 h. The bupivacaine concentration decreased by 54% and 45%, on average, during the first 6 h following the 24- and 48-h infusions, respectively. On average, the highest DBB concentrations were measured 2 h after the 24-h infusion (0.31 +/- 0.18 micrograms/ml) and 30 min after the 48-h infusion (0.33 +/- 0.13 micrograms/ml). The highest 4-OHB concentrations were measured 1 h (0.18 +/- 0.09 micrograms/ml) and 30 min (0.20 +/- 0.05 micrograms/ml) after the 24- and 48-h infusions, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Enhanced brachial plexus blockade. Effect of pain and muscular exercises on the efficiency of brachial plexus blockade

Three groups each of 20 patients scheduled to undergo operations on hand or forearm, received supraclavicular brachial plexus blocks with 25 ml lignocaine 1.5%. Patients in the control group did not suffer from pain and were not asked to do muscular exercise. Patients with acute trauma of the upper limb formed the pain group and showed significantly decreased latency for onset of analgesia, partial and complete muscle paralysis. Patients in the muscle exercise group were free of pain and were asked to do muscular exercise for 5 minutes after injection of the lignocaine. Onset of analgesia, partial and complete muscle paralysis was significantly more rapid than in both control and pain groups. Changes in the duration of block were not significant. It is concluded that pain and muscular exercise enhance the onset of brachial plexus blockade.     

An unusual toxic reaction to axillary block by mepivacaine with adrenaline

An increase in blood pressure, accompanied by atrial fibrillation, agitation, incomprehensible shouts and loss of consciousness, was observed in an elderly, ASA classification group II, cardio-vascularly medicated male, 12 min after performance of axillary block with mepivacaine 850 mg containing adrenaline 0.225 mg, for correction of Dupuytren's contracture. After intravenous administration of labetalol, metoprolol and midazolam the patient's condition improved, and 15 min later he woke up. The block was successful and surgery was conducted as scheduled despite persisting atrial fibrillation. Postoperatively, the patient refused DC cardioversion and was treated medically. Both the temporal relationship of events and the response to treatment suggest that a rapid systemic absorption of mepivacaine with adrenaline and/or interaction of these drugs with the patient's cardiovascular medications were responsible for the perioperative complications.     

0.75% and 0.5% ropivacaine for axillary brachial plexus block: a clinical comparison with 0.5% bupivacaine

BACKGROUND AND OBJECTIVES: Although ropivacaine has been extensively studied for epidural anesthesia, very few reports exist on brachial plexus block. We therefore decided to investigate the clinical features of axillary brachial plexus anesthesia with two different concentrations of ropivacaine (0.5% and 0.75%) and to compare the results with those obtained with 0.5% bupivacaine. METHODS: Three groups of patients were randomized and prospectively studied. They received, in a double-blind fashion, 32 mL of the local anesthetic solution into the midaxilla, by a nerve-stimulator technique. Onset time in each of the stimulated nerves was recorded both for the sensory and motor block. Peak time (ready to surgery), rate of supplemental blocks, need for intraoperative opioids, duration of sensory and motor block, postoperative analgesic requirements, and patient satisfaction were also recorded. RESULTS: The rate of complete sensory and motor block observed with both ropivacaine groups was higher at 10, 15, and 20 minutes postinjection (P < .001). The mean peak time was shorter with ropivacaine than with bupivacaine (R50 = 16.37 minutes, R75 = 14.7 minutes, B = 22.3 minutes, P < .05). The quality of the anesthesia was higher with ropivacaine, as measured by the intraoperative needs for opioids and the overall patient's satisfaction (P < .05). No significant differences were noted with all the other studied parameters. CONCLUSION: Ropivacaine showed advantages over bupivacaine for axillary brachial plexus block. Because no statistical differences were found between the two ropivacaine groups, we therefore conclude that 0.75% does not add benefit and that 0.5% ropivacaine should be used to perform axillary brachial plexus blocks.     

Infraclavicular coracoid approach brachial plexus block for radial club hand repair

BACKGROUND: Radial club hand is a congenital deformity in which the radius is absent, the metacarpophylangeal and interphalayngeal joints are fused and muscles arising from the radius are absent. This can alter the motor response to peripheral nerve stimulation. The classical motor response to median nerve stimulation (contractions of the fingers) cannot be elicited, hence fine twitches in the hand, at the wrist or in the surgical area or pronation-supination at a current of 0.5 mA were taken as endpoints. The aim of this study was to assess the feasibility of achieving successful infraclavicular coracoid approach block in the intra- and postoperative periods when ideal responses to electrical nerve stimulation are absent because of congenital anomalies. METHODS: Thirty-five patients aged 8 months to 2 years, weighing 7-12 kg were selected and the blocks were performed under light general anesthesia. Fentanyl 2 microg.kg(-1) was used as rescue analgesic in case of block failure. Postoperatively CHEOPS pain score was recorded at h1, h4 h6, h8, and h10 postoperatively. Tramadol 2 mg.kg(-1) was given in case of inadequate pain relief (CHEOPS>4). RESULTS: In no patient could we elicit the finger flexion response which is typical of median nerve stimulation. Intraoperatively, one out of 35 children (3.3%) showed reaction to pain. In the postoperative period two out of 35 (6%) children had high pain scores and were given tramadol. Analgesia lasted for 6.5+/-1.50 h. CONCLUSIONS: Despite the limitation of absence of an ideal response to nerve stimulation in radial club hand, endpoints such as fine twitches in the hand, at the wrist or in the surgical area or pronation-supination were sufficient to achieve a successful block. This block gives satisfactory intra- and postoperative analgesia.