Ultrasound-assisted combined interscalene-supraclavicular block using different concentrations and volumes of local anesthetics for humeral neck fracture surgery

INTRODUCTION

The shoulder is supplied by multiple peripheral nerves.^[1] These are the subscapular, axillary, and lateral pectoral nerves.^[1] The structures around the shoulder and its joints were also innervated by nerves from the brachial plexus, i.e., the muscles that rotate and protect the joint, bursa, as well as its ligaments.^[1] These peripheral nerves innervating the shoulder, its surrounding structures, originate from the proximal part of the brachial plexus.^[1] Therefore, the brachial plexus block for surgical interventions of the upper humerus presents a unique difficult task to the anesthesiologist as there is no one best block that can provide an optimal anesthesia in the pre-operative period with a satisfactory outcome.^[2] Thus, the anesthesia management for the upper humeral surgical procedures ranges from general anesthetic technique only or co-joined with brachial plexus nerve block.^[2] However, USA dual interscalene-supraclavicular brachial plexus block can improve the precision and success rate of the regional block. It allowed utilization of reduced volume and concentration and improved overall perioperative management.^[2,3]

CASE REPORT

A 42-year-old businessman presented to the orthopedic clinic with a 3-week history of inability to use the left hand following an accidental push to the wall, with associated severe pain in the arm area and swelling. The patient had no history of bleeding from the site. On the same day of the incident, the patient had traditional bone setter manipulation of the hand, but no improvement. There is no previous history of surgery or anesthesia. The patient’s weight was found to be 75 kg; height 1.72 m, Glasgow coma score: 15/15, cardiovascular system: Pulse rate: 100 beats/min; blood pressure: 150/80 mmHg; and a respiratory rate of 16 circles per minute. Assessment of closed left humeral neck fracture was entertained.

The following investigations were requested: X-rays of the proximal left humerus and shoulder, electrolyte, urea, creatinine, full blood count (FBC), and differentials. The patient was counseled for open reduction and internal fixation with a plate and screw. The arm sling was applied, and analgesics were continued. FBC and differential results were within acceptable limits with a platelet of 197000/uL, and the clotting profile was essentially normal. The electrolytes, urea, and creatinine were also normal, with sodium 138 mmol/L and potassium 3.8 mmol/L.

Assessment of a humeral neck fracture was confirmed, and the patient was admitted to the orthopedic ward for surgery. The night before the surgery’s visit by the anesthetist revealed the additional finding of Mallampati score of II and Assessment of American Society of Anesthesiology II. The patient was planned to fast from midnight for solids and allow clear water up to 6 am, for surgery under the USA combined interscalene and supraclavicular brachial plexus block and conscious sedation. Informed consent for anesthesia was obtained and the patient was instructed to take Oral diazepam 10 mg at night, and another 10 mg in the morning of the surgery at 6 am with a sip of water.

On the morning of the surgery, in the theater, the following was prepared for the regional anesthesia: An ultrasound machine (M-Turbo ultrasound machine, FUJIFILM SonoSite, Inc., Bothell, WA 98021 USA), a linear (13-6MHz) transducer probe, two size 20 mL syringes, 0.5% bupivacaine (Duracaine, plain), dexamethasone 4 mg (philodexa), multi-parameter patient monitor, Dash 4000 (SOKOMED, Laguna Niguel, USA). Non-invasive blood pressure device and peripheral pulse oximetry (CAS M. California, USA) and Electro cardiogram (ECG). The initial’s heart rate, blood pressure, peripheral oxygen saturation, and respiratory cycles were taken as baseline values: A peripheral intravenous cannula (size 18 G) was set.

Supraclavicular block, with the patient on the operation table lying supine, having his head turned to the contralateral side. The skin over the left neck and supraclavicular area was cleaned and prepared with an aseptic solution to maintain sterility. Intravenous ceftriaxone 1 g was given prophylactically. A pre-block scan was carried out to visualize the roots and trunks (the supraclavicular and the interscalene grooves). The patient was draped, and his supraclavicular groove was scanned to locate his subclavian artery, first rib, pleura, and trunks of the brachial plexus, after which the size 20-gauge, 5 cm, echogenic needle was introduced from the right to left side under the long axis of the ultrasound probe (using the in-plane technique). The needle was advanced toward the “corner pocket.” The lower trunk is commonly located at this area, in between subclavian artery on the medial side, the first rib below, and the plexus at the top, and then, 10 mL out of the 20 mL mixture of 0.25% bupivacaine plus 4 mg/1 mL dexamethasone was injected with intermittent aspiration at every 3–5 mL to avoid intravascular injection, and the other 10 mL of the mixture was injected just above and lateral to the subclavian artery. The ultrasound transducer probe was placed in the interscalene groove at the level of the cricoid cartilage to have a transverse view of the root’s brachial plexus. The nerve root in the interscalene groove has a hypoechoic appearance. Characteristic round or oval structures were located between the two interscalene muscles, the anterior and middle scalene. A 5 cm 20 G needle was introduced from one end of the ultrasound transducer (in-plane technique), and the needle was threaded in. However, care was ensured to monitor the tip of the needle to prevent intraneural entry, and while injecting the drug solution and dispersing the anesthetics, extra care was taken to see the tip of the needle during advancement, and 10 mL of 0.5% bupivacaine plus 4 mg dexamethasone were used for interscalene block targeting the C5-C8 nerve roots. The setting of both sensory and motor anesthesia was assessed and recorded. The sensory block was determined with the pinprick along the dermatome area. While the motor blocks for the respective nerves (radial, ulnar, and median) were assessed with handgrip and coordination. Complete surgical anesthesia was achieved 15 min after the block. The patient was continually monitored for respiratory movement (symmetrically equal), peripheral oxygen saturation (kept at 97–100%), and blood pressure. Before the surgical incision, the patient was sedated using Keta-prof (a combination of ketamine 50 mg and 30 mg propofol) intravenous bolus start. Oxygen supplement was given through a facemask at 5 L/min. His vitals have been stable throughout the operation time, which took 2 h. Postoperatively, the patient was transferred to the ward, and intravenous paracetamol 900 mg 6 hourly, intramuscular diclofenac 75 mg 12 hourly, and intravenous pentazocin 60 mg 8 hourly were prescribed if the patient complained of pain or when NRS is > 4. However, his pain assessment remained <4 throughout the 1^st operative day. There was no complaint of pains, dyspnea, voice hoarseness, or hiccups during the pre-operative period. Furthermore, signs of Horner’s syndrome were not observed. The patient was allowed to go home on the 3^rd post-operative day after repeat X-ray of the surgical site.

DISCUSSION

This case report demonstrated the effectiveness of dual inter-scalene, supraclavicular nerve block as a primary anesthesia modality for upper humeral surgical procedures with excellent post-operative analgesia without any side effects related to the procedure or drug. These findings were in keeping with Saad et al. findings^[4] in their study of dual interscalene and supraclavicular block among 30 chronic renal patients, where they recorded excellent intra- and post-operative results. Similarly, we achieved complete motor and sensory anesthesia 15 min after the block and extended 24 h of post-operative analgesia. This corresponds with the adequate analgesia recorded by Pehlivan et al.^[5] in a randomized comparative study between interscalene and combined interscalenesuprascapular blocks for arthroscopic shoulder surgery, where they recorded good analgesia coverage in the combined group within the first 24 h. Similarly, throughout the study period, the incidence of dyspnea, voice hoarseness, pneumothorax, spinal cord injury, and signs of Horner’s Syndrome were monitored, but none were observed in our study. This was similar to the results of the Kaciroglu et al.^[6] study. Similar to the findings of McNaught et al.^[7] study reduced volume of local anesthetic (LA) from 20 mL to 5 mL in interscalene block, where they observed that it spared the phrenic nerve, thereby preserving the diaphragmatic function with optimal analgesia and fewer needle pricks.

CONCLUSION

Combined ultrasound-assisted interscalene-supraclavicular nerve blockade using reduced volume, and concentration, may be cognized as anesthesia modality for proximal humeral fracture. It is also safe and can provide good postoperative extended analgesia. However, further study should be carried out to substantiate these findings.