Brachial plexus block

A supraclavicular brachial plexus block was performed which resulted in unilateral sensory and motor blockade of the thoracic and abdominal walls. General anaesthesia was therefore used and postoperatively it was noticed that analgesia of the upper limb had developed. It is likely that the blockade resulted from an intrapleural injection of local anaesthetic.     

Distribution of evoked paraesthesiae and effectiveness of brachial plexus block

The distribution of paraesthesiae evoked by a low power nerve stimulator during performance of supraclavicular brachial plexus block was studied in 120 patients. Evoked paraesthesiae in the distribution of the median nerve was associated with a significant improvement in effectiveness of the block when compared with evoked paraesthesiae in the ulnar and radial distributions. A possible explanation for this finding is proposed.     

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.     

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.     

Axillary brachial plexus block for perioperative analgesia in 250 children

A cannula technique for axillary brachial plexus block in combination with general anaesthesia has been in use since 1994 for children undergoing surgical correction of congenital hand anomalies. During a 4-year period data were collected on 250 procedures in 185 patients of median age 3 years detailing the block technique and the intraoperative and postoperative analgesic requirements. Fifteen patients (6%) required supplemental intravenous opioid intraoperatively and this is taken as a marker of failure of the block. Ninety-five patients (38%) required postoperative codeine phosphate with a mean time to receiving codeine phosphate of 9 h. Postoperative pain was controlled in this series with oral analgesia in all but six patients who received parenteral codeine. It is proposed that a cannula technique is an effective and safe method of producing axillary brachial plexus block in children.     

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.     

Prolonged hemidiaphragmatic paralysis following interscalene brachial plexus block

We present a case of persistent phrenic nerve paralysis after a successful interscalene brachial plexus block. In addition, there was no observed diaphragmatic stimulation, and the patient underwent an uneventful early postoperative period. Warning signs of a complication were either missed or absent until several days after discharge from the ambulatory surgical unit.     

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.     

Continuous infraclavicular brachial plexus block in a child

Continuous regional anesthesia for both intra- and postoperative use in adults is becoming more common. As with many new anesthesia techniques, however, there is often a lag time before the same techniques are utilized in children. Our patient was a 10-year-old child requiring reoperation on her fifth digit with planned 48-h admission for range of motion exercises. We wanted to have a continuous regional blockade to control the patient's pain during the postoperative manipulations of the digit. A search of the literature from the last 10 years did not show any reports of the placements of a continuous brachial plexus block in children. In this case report, we present the successful placement and use of a continuous infraclavicular catheter in a child undergoing upper extremity surgery.     

Blood flow in the upper limb during brachial plexus anaesthesia

Changes in finger blood flow, arm blood flow and cardiac output were measured using electrical impedance plethysmography in 20 patients after brachial plexus anaesthesia. The anaesthetic solution used in all patients was 1% lignocaine with adrenaline 1:200,000. Significant increases in cardiac output and blood flow to the unanaesthetised arm were observed immediately after anaesthesia had become effective. A highly significant increase in the blood flow to fingers of the blocked hand was observed throughout the period of anaesthesia but there was no overall increase in the blood flow to the arm. It is suggested that the adrenaline contained in the local anaesthetic solution increased the cardiac output and caused arterial vasoconstriction at the site of injection.     

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     

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.     

Incidence of diaphragmatic paralysis following supraclavicular brachial plexus block and its effect on pulmonary function

Thirty unpremedicated ASA physical status 1-3 patients aged between 18 and 69 years, scheduled for upper limb surgery, received a conventional supraclavicular brachial plexus block using a nerve stimulator and bupivacaine 0.375% 0.5 ml.kg-1. Spirometric measurements of pulmonary function and ultrasonographic assessments of diaphragmatic function were made before the block and at 10-min intervals after injection until full motor block of the brachial plexus had developed. Complete paralysis of the ipsilateral hemidiaphragm occurred in 50% of patients. Seventeen per cent of patients had reduced diaphragmatic movement and the rest (33%) had no change in diaphragmatic movement. Those with complete paralysis all showed significant decreases in pulmonary function, whereas those with reduced or normal movement had minimal change. All patients remained asymptomatic throughout, with normal oxygen saturation on room air.     

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.     

Brachial plexus injury occurring during breast surgery

A case of brachial plexus injury occurring during axillary dissection as part of breast conservative surgery for breast cancer is reported. The mechanisms, diagnosis and management of such injury are discussed. Proper positioning of the patient is the key to preventing brachial plexus injury.      

Latency of brachial plexus block The effect on onset time of warming local anaesthetic solutions

A double-blind study was set up to investigate the effect of warming local anaesthetic solutions on the latency of onset of subclavian perivascular brachial plexus blocks. Twenty-four adult patients were randomly allocated into two equal groups. In group A the local anaesthetic was injected at room temperature, while in group B the local anaesthetic solution was prewarmed to 37 degrees C in a thermostatically controlled heating block. All blocks were performed using 0.5 ml/kg of a solution prepared by mixing equal volumes of 0.5% bupivacaine with adrenaline 1:200,000, and 1% prilocaine. The speed of onset of sensory blockade was significantly increased when the temperature of the local anaesthetic solution was increased to 37 degrees C. There were no adverse side effects in either group.     

Comparison of three different volumes of mepivacaine in axillary plexus block using multiple nerve stimulation

Background. The multiple injection technique for axillary block,in which the four distal nerves of the plexus are located bya nerve stimulator and separately injected, has been shown toprovide a high success rate and a short onset time. This randomizeddouble-blind study was conducted to compare the effectivenessof three different volumes of mepivacaine 10 mg ml^–1 inpatients undergoing elective distal upper limb surgery underaxillary brachial plexus block with the four-nerve approach.The number of complete sensory blocks was the primary efficacyvariable. Methods. A total of 114 adult patients were randomly allocatedto receive 36 (n=38), 28 (n=38), and 20 ml (n=38) of mepivacaine10 mg ml^–1. In each group, volumes were equally distributedin the four nerve territories. In all patients, performancetime, latency time, block characteristics, need of supplementaryblocks, tourniquet tolerance, duration of analgesia, and complicationswere recorded. Results. Complete sensory block was obtained in 97% of patientsreceiving a volume of 36 ml, 97% of those receiving 28 ml, and94% of those receiving 20 ml. One patient in the group of 28ml and five patients in the group of 20 ml experienced painon inflation of the tourniquet. Two months after surgery, nocase of postoperative neurological dysfunction was observed. Conclusions. The three volumes (38, 28, and 20 ml) of mepivacaine10 mg ml^–1 ensured a similar and high percentage of completesensory blocks in axillary brachial plexus anaesthesia withnerve stimulation involving the location of four motor responses. Br J Anaesth 2003; 91: 519–24