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Correspondence  |   July 2007
Transient Neurological Dysfunction after Continuous Femoral Nerve Block: Should This Change Our Practice?
Author Notes
  • (Accepted for publication March 22, 2007.)
    (Accepted for publication March 22, 2007.)×
Article Information
Correspondence
Correspondence   |   July 2007
Transient Neurological Dysfunction after Continuous Femoral Nerve Block: Should This Change Our Practice?
Anesthesiology 7 2007, Vol.107, 178. doi:10.1097/01.anes.0000268571.31182.74
Anesthesiology 7 2007, Vol.107, 178. doi:10.1097/01.anes.0000268571.31182.74
In Reply:—
We thank Drs. Eipe, McCartney, and Kummer for their interest in our case report regarding preexisting subclinical neuropathy as a risk factor for nerve injury after continuous ropivacaine administration through a femoral catheter.1 
We did not intend to promote guidelines to change regional anesthesia daily practice with this case report. The modest aim was to make anesthesiologists aware of the possibility to evidence the presence of preexisting subclinical neuropathy even after new nerve damage has occurred.
The term “well-recognized complication” has been misunderstood by Eipe et al. This is a semantic question. “Well-recognized,” according to the work of Selander and others,2 ,3  means that in certain conditions, the needle and local anesthetics can damage the nerve. This is a well-recognized reality. This statement has nothing to do with incidence. We completely agree with Eipe et al. that nerve injury related to regional anesthesia is a very rare occurrence.4 ,5  It seems that improved needle design, new safer approaches, and better technical application of block performance help to steadily decrease the incidence of this problem.
We cannot absolutely exclude the responsibility of the tourniquet, but its implication in this case seems very unlikely because tourniquet-induced nerve damage is almost always a conduction block which can be precisely localized by the means of somatosensory evoked potentials.6 ,7  In this case, we had signs of nerve denervation not localized at the site of tourniquet application.
We want to emphasize once more the importance of early postoperative neurophysiologic examination in case of occurrence of new neurologic deficits. This helps to prove or rule out a preexisting and undiagnosed neuropathy, which might have important medicolegal issues. Finally, we completely agree with Eipe et al. that good practice of regional anesthesia begins preoperatively and continues long after completion of surgery.
Stephan Blumenthal, M.D. Alain Borgeat, M.D.,* Konrad Maurer, M.D. Beatrice Beck-Schimmer, M.D. Uta Kliesch, M.D. Michael Marquardt, M.D. Judith Urech, M.D. *Orthopedic University Clinic Zurich, Zurich, Switzerland. alain.borgeat@balgrist.ch
References
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