Benjamin Franklin, who first said “time is money,” would have loved peripheral nerve blocks. They help surgery patients recover faster and go home sooner without pain or post-operative nausea and vomiting. But we need to remember that for PNBs, time is also safety. It pays off to invest time up front in a thorough history and physical (H&P) and good patient education.
History and physical
The first investment opportunity occurs with the H&P. Conversion to general anesthesia is always possible, so we must assess the heart, lungs, operative site and vital signs and understand the patient's comorbidities. In addition, we should work hard to diagnose pre-existing neuromuscular conditions, since these can increase the risk of peripheral-nerve-block-related complications. For example, if the practitioner overlooks contralateral phrenic nerve palsy (which can result from prior surgery) and the patient receives an interscalene block, immediate respiratory failure could result, since this block nearly always blocks the ipsilateral phrenic nerve.
In my practice, I obtain a thorough history of relevant neuromuscular medications, work to locate even small degrees of numbness or weakness in any area of the patient's body, and obtain a complete history of prior trauma and broken bones—both of which can lead to neuromuscular weakness. Patients can forget seemingly minor disabilities for which they have learned to compensate. Yet a patient who recovers from a brachial plexus block with a numb pinky finger may blame surgery even when the problem was pre-existing. A thorough H&P will uncover these conditions beforehand.
The second investment opportunity is good patient education. Informed patients tend to require less anxiolysis, are competent to prevent injury to the insensate limb, and know to call the practitioner at the first sign of potential complications.
I use a three-part approach. First, I describe the entire peripheral nerve block procedure using simple language. For example, we call the nerve stimulator a “glorified depth finder for the nerve” and patients immediately understand the concept. We demonstrate how the equipment works before the procedure so that patients aren't surprised when they see large needles, hear the stimulator's beeps, and feel twitching as we approach the nerve. Second, together with the patient, we decide how much sedation to use, if any. This ensures we are meeting patients' needs, and they go into surgery with a sense of control rather than a feeling of anxiety. Lastly, we perform thorough post-op education. We let each patient know how long the block should last, how to prevent injury to the insensate limb, and provide a list of post-block analgesic options. We review all possible adverse effects and provide 24/7 contact information. We tell patients who receive interscalene brachial plexus blocks, for example, that they may experience Horner's syndrome, transient hoarseness, and/or nasal congestion. Education and reassurance really do help prevent patient anxiety.
With peripheral nerve block patients, pre-surgical shortcuts are a false economy. When we give our patients the attention they deserve, both time and safety are on our side.
Dr. Mayfield is Medical Director of Perioperative Services and Vice Chairman of Anesthesiology and Perioperative Medicine with the Medical College of Georgia in Augusta.