Combined Infraclavicular Plexus Block with Suprascapular Nerve Block for Humeral Head Surgery in a Patient with Respiratory Failure: An Alternative Approach

A 43-yr-old man with chronic bronchial asthma suffering from frequent episodes of acute bronchospasm was admitted in the emergency department of our hospital with a traumatic fracture of the left humeral head. The patient brought the results of his lung function test performed during stable periods of the disease, which showed a pattern of severe airway obstruction, a forced vital capacity of 2.93 l (65% of predicted), a forced expiratory volume in 1 s of 1.13 l (32% of predicted), and a lung residual volume of 4.29 l (222% of predicted). The patient was in long-term therapy with inhaled long-term β²agonists, inhaled steroids, and oral prednisone, 15 mg per day.

Preanesthetic examination showed a patient with dyspnea at rest, tachypnea (32 breaths/min), and wheezing. While 35% oxygen was administered by Venturi mask, arterial blood gas analysis showed a pH of 7.40, a Pao²of 62 mmHg, and a Paco²of 36.7 mmHg. Inhaled albuterol, 5 mg, in saline solution and 100 mg intravenous prednisolone were administered, and the patient's clinical status improved after 60 min. Due to the high risk of axillary nerve compression, immediate reduction and surgical stabilization of the humeral fracture was indicated. The patient was premedicated with 2 mg intravenous midazolam (Midazolam ROVI^®; ROVI Pharmaceutical Laboratories, Madrid, Spain) and 25 mg intravenous ketamine (Ketolar^®; Parke-Davis, Madrid, Spain) before anesthetic block. The suprascapular nerve block was performed at the suprascapular notch with the patient sitting up and leaning forward using the posterior approach, as described by Moore. 3The suprascapular nerve was identified by using a nerve stimulator (Stimuplex-NHS II; B. Braun, Melsungen, Germany) connected to a needle (Stimuplex A 50, B. Braun, Melsungen, Germany). When infraspinatus muscle contraction was observed at 0.5 mA current, 10 ml mepivacaine, 1% (Scandinibsa 1%, Inibsa Laboratories, Barcelona, Spain), was injected. Brachial plexus block was performed using the coracoid and infraclavicular technique. The coracoid process was identified, and the needle (Stimuplex A 50) was introduced perpendicular to coronal and parasagittally at a point located 2 cm medial and caudal to it, as described by Wilson et al.  4When muscular contraction in the hand was observed at 0.5 mA current, 40 ml mepivacaine, 1%, was injected. Complete anesthetic block was obtained in the left upper limb, and the patient was able to undergo surgery comfortably and without incident. The duration of surgery was 95 min. Peripheral oxygen saturation was maintained at more than 96% during the operation and in the immediate postoperative period. Postoperative outcome was uneventful, and the patient was discharged from the hospital 3 days after surgery.

A general anesthetic was not considered in this patient because of the presence of severe bronchospasm with acute respiratory insufficiency. Because of the risk of ipsilateral diaphragmatic paralysis associated with interscalene block, 1,2this technique was also contraindicated. Likewise, the incidence of phrenic nerve block and diaphragmatic paralysis is approximately 67–80% after supraclavicular techniques for brachial plexus block, 5,6which are also associated with the risk of pneumothorax. Infraclavicular approaches to brachial plexus block have similar anesthetic efficacy as supraclavicular techniques, 6are more effective than the axillary approach, and minimize the complications associated with supraclavicular approaches. 7,8The infraclavicular brachial plexus technique produces an anesthetic effect over the brachial plexus and the infraclavicular collateral nerves—the subscapular nerve (C5–C6), axillary nerve (C5–C6), and lateral pectoral nerve (C5–C6), 9which provide sensation to the anterior joint of the shoulder. However, the suprascapular nerve, a collateral branch of the upper trunk of the brachial plexus providing sensation to the posterior shoulder joint capsule, is not blocked by infraclavicular techniques. For this reason, in the present case we decided to combine vertical infraclavicular access with selective suprascapular nerve block, as described by Moore, 3to achieve complete shoulder blockade. We obtained a good anesthetic block without any side effects on pulmonary function. Clinical effects of different blocks are shown in figure 1.

Nevertheless, both of the techniques used in this patient produce discomfort during performance, and light sedation is recommended. A combination of low doses of ketamine and midazolam was chosen because of its bronchodilator effects and relative absence of respiratory depressant effects.

The combination of infraclavicular plexus block with suprascapular nerve block has not been described for shoulder surgery, and, after our experience in the case presented, we think that it could be an alternative in patients with severe pulmonary disease requiring regional anesthesia for shoulder surgery.