Volume 18, Issue 7 , Pages 833-834, July 2007
Brachial Plexus Injury Related to Patient Positioning
Article Outline
Clinical Case
A 45-year-old woman presented with a recurrent L1-3 spinal giant cell tumor. She had previously undergone surgery for the same problem, at which posterior lumbar spine fixation was performed. She was referred to the interventional radiology department for preoperative tumor embolization. The procedure was performed with the patient under general anesthesia. The patient was placed in the supine position with her arms by her side at the start of the procedure. Because of extensive spinal fixation devices, it was difficult to visualize the area of interest to perform the embolization procedure safely. The patient was repositioned with both shoulders flexed to 120° and both elbows flexed to 90° (Fig 1). The patient was maintained in this position for the rest of the procedure, which lasted 4 hours.
Figure 1.
Photograph shows incorrect positioning, with the patient’s arms raised above the head.
The following day, the patient complained of numbness and weakness in her left upper extremity. A neurologic consultation was obtained, and a C5 brachial plexus neuropraxy was diagnosed on the basis of clinical evaluation. No specific treatment was given for the left upper extremity neuropraxy. During the next 4 days, her left upper arm sensation and motor power gradually returned. She had no residual neurological deficits. Findings at 3-month follow-up were unremarkable for upper extremity neurologic deficits.
What Happened and Why
The cause of the brachial plexus injury during our patient’s procedure under general anesthesia was due to positioning with the hands and arms above the head in the supine position. The exaggerated abduction of the arms caused stretching of the plexus, which led to the injury. The longer the stress to the brachial plexus, the more severe the injury is likely to be; in our patient, the time of immobilization was 4 hours.
Discussion
This case illustrates iatrogenic brachial plexus injury. The brachial plexus is the second most common peripheral nerve to be injured due to improper positioning of the patient during general anesthesia, after the ulnar nerve (1). Despite careful positioning and awareness of the possibility of injury, brachial plexus injury occurs in approximately 0.2% of patients who receive general anesthesia (2). Brachial plexus injuries that occur secondary to malpositioning of patients during general anesthesia are well known to the surgical world. To our knowledge, Shankar et al (2) are the only investigators to report on a brachial plexus injury that occurred as a result of patient positioning during a radiologic procedure. The injury occurred after computed tomography–guided radiofrequency ablation.
The brachial plexus is firmly attached proximally to the vertebra and prevertebral fascia and is tethered distally to the axillary sheath in the middle and distal parts of the arm. Its mobility and close proximity to bone structures such as the first rib, clavicle, coracoid process, and head of the humerus cause it to be easily compressed when the arm is improperly positioned. Traction to the plexus results in injury to the vasa nervosum and subsequent ischemia to the plexus (3). In a patient who is awake, the ischemic changes manifest as pain, numbness, and motor weakness. During general anesthesia, when the muscle tone is already reduced by muscle relaxants and anesthetic agents, the patient is unable to perceive pain, numbness, and motor weakness. Thus, the potential for this complication is high.
To prevent brachial plexus injury that may be related to periprocedural positioning of patients, extension and external rotation in the supine position can be avoided by limiting the abduction to no more than 90° and always keeping the head in a neutral position (4) (Fig 2). Almost all patients reported to have a brachial plexus injury as a result of body malpositioning had a complete recovery (2). The recovery time ranged from hours to 1 year, depending on the severity of the injury and associated medical conditions (eg, diabetes mellitus, chronic alcoholism, arteriosclerosis, hypotension, and pernicious anemia). Patients with a sensory deficit will recover before those with a motor disturbance.
Figure 2.
Photograph shows correct positioning, with the patient’s arms folded across the chest.
Nerve injuries related to patient positioning during anesthesia have also been described for the ulnar, common peroneal, and sciatic nerves. Ulnar injury is the most common (1). It is related to the superficial path of this nerve within the closed confines of the cubital tunnel along the medial epicondyle of the humerus (1, 5). Procedures in which the forearm is placed in an extended and pronated position on an arm board and/or table make the ulnar nerve vulnerable to compressive injury. Extreme flexion of the elbow (eg, during lung biopsy and/or radiofrequency ablation to get the scapula out of the needle path) can stretch the nerve around the medial epicondyle and cause ulnar nerve injury. Avoidance of these positions and the use of adequate padding at the elbow have been recommended to prevent ulnar nerve injuries.
Injuries to the common peroneal nerve can occur from compression of the nerve against the head of the fibula and the procedure table supports during procedures performed with the patient in the lithotomy position (1). Interventional radiology procedures that require the patient to be in this position (eg, fallopian tube recanalization) require careful padding on the lateral aspect of the knee to avoid this injury. Sciatic nerve injury has been described in thin patients undergoing prolonged procedures on a hard table when the opposite buttock is elevated (as in hip pinning procedures) (1). Again, knowledge of this complication, avoidance of these positions if possible, and the use of adequate protective padding are recommended to avoid these injuries.
References
- . Peripheral nerve injury associated with anesthesia. Anaesthesia. 2000;55:980–991
- Brachial plexus injury from CT guided RF ablation under general anesthesia. Cardiovasc Intervent Radiol. 2005;28:646–648
- . Brachial plexus injury due to compression: an alternative mechanism: case report and review of the literature. Am Surg. 1997;63:487–489
- . The prevention of injuries of the brachial plexus secondary to malpositioning during surgery. Clin Orthop. 1998;228:33–41
- . Nerve injury associated with anesthesia: a closed claims analysis. Anesthesiology. 1999;90:1062–1069
None of the authors have identified a conflict of interest.
PII: S1051-0443(07)00773-7
doi:10.1016/j.jvir.2007.04.033
© 2007 SIR. Published by Elsevier Inc. All rights reserved.
Volume 18, Issue 7 , Pages 833-834, July 2007
