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P229 Peripheral nerve injury after nerve blockade
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Abstracts / Clinical Neurophysiology 128 (2017) e178–e303
of GBS. Whereas AIDP patients generally have proximally enlarged nerves in the ultrasound, our AMAN-patient showed a distally enlarged median nerve, possibly related to the distal conduction failure.
Keywords: AMAN, Axonal conduction blocks, Nerve ultrasound doi:10.1016/j.clinph.2017.07.236
P229 Peripheral nerve injury after nerve blockade—Nils Wolfram, Janus Kaufmann Lindquist, Martin Lauritzen (Rigshospitalet Glostrup, Clinical Neurophysiology, Copenhagen, Denmark) Objectives: Nerve blockade is a common procedure in peripheral limb surgery. In some cases however the anesthesia is directly followed by distally paresis and/or sensory disturbance. Method: We describe the neurophysiological and ultasonographic findings of 5 cases in this patient group. Results: 5 patients were examined clinically, neurophysiologically and with ultrasonography. All patients had permanent paresis and/or sensory disturbance proximal to the site of surgery and distal to the site of peripheral nerve blockade. Neurophysiological findings showed markedly side-difference of motor – and sensory amplitudes suggesting axonal degeneration. Ultrasonography showed increased cross-sectional area/long-axis diameter of affected nerves and changes in intraneural and epineural structures at site of local anesthesia injection. Discussion: Nerve injury following peripheral nerve blockade is a well-known complication, but the mechanisms are not well understood, specifically and ultrasonographic data are not yet available. Our series of patients showed axonal disturbance in several nerves distal to the site of peripheral nerve blockade. Ultrasonography showed morphological nerve changes at the side of anesthesia placement. Conclusions: Peripheral nerve anesthesia may cause axonal motor and sensory nerve degeneration distally to anesthesia placement. Ultrasonographic changes in the nerve are mostly present at the site of anesthesia placement. Significance: Peripheral nerve injury after nerve blockade has been described previously but the mechanisms are not understood - neurophysiological and ultrasonographic examinations are valuable and may contribute to an understanding of desease mechanisms. Our study may be of help in assessing the safety of local anesrhetics and potentially prevent persistent side-effects and nerve injury following the use of local anesthesia for limb surgery.
Keywords: Peripheral nerve injury, Nerve blockade, Neurophysiology, Ultrasound doi:10.1016/j.clinph.2017.07.237
P230 Ulnar epineural discontinuity and electrophysiological changes in a young girl following ulnar fracture—Janus Kaufmann Lindqvist, Nils Wolfram (University of Copenhagen, Department of Clinical Neurophysiology, Glostrup, Denmark) Objectives: Electrophysiologic evaluation of traumatic peripheral nerve lesions can be complicated, especially in children where the given diagnosis can have dire consequences especially if not accurate.
Method: electrophysiological and sonographic consecutive examinations during a timelapse of 2 years (4 examinations). Results: A 10 year old girl developed a severe ulnar neuropathy following a fracture of both forearm bones. Electrophysiology resembled complete denervation without any motoric or sensory answers. EMG revealed spontaneous activity in the interosseous dorsalis 1 muscle in the affected arm. Sonography visualized the nerve with an epineural defect but in continuity. We followed the girl in a timespace over 2 years with a total of 4 examinations. As the epineural defect diminished the electrophysiologic changes recovered. At the 4 examination the sonographic appearance was normalized except a slight neuroma at the lesion site. Discussion: Decision making following traumatic nerve lesions relies heavily on electrodiagnostic testing. In this case we have shown that an epineural defect can ‘‘mimick” nerve discontinuity electrophysiologic. Sonography revealed the nerve in continuity and the nerve function slowly regained following the recovery of the epineurium. Conclusions: Epineural defects can have an electrophysiological appearance resembling complete denervation in the recovery period. If sonography shows nerve continuity a conservative approach could be recommended. Significance: Sonography can help along with electrophysiology in differentiating between severed nerves and nerve changes electrophysiologically resembling complete denervation. The case could argue that sonography should be performed in all traumatic nerve lesions.
Keywords: Peripheral nerve injury, Traumatic nerve injury, Neurophysiology, Sonography doi:10.1016/j.clinph.2017.07.238
P231 High resolution ultrasound of peripheral nerves in amyotrophic lateral sclerosis—Erisela Qerama, Simon Østergaard Wehrs, Sara Silkær Bak *, Maria Thelin Johansson, Anders Fuglsang-Frederiksen (Aarhus University Hospital, Department of Neurophysiology, Aarhus, Denmark)
Introduction: In this study we examined whether the ultrasound (UL) measurement of median and ulnar nerves are different in ALS patients compared with healthy subjects(HS) and whether US can be used to demonstrate the progressive axonal loss by showing decrease in cross-sectional area (CSA) of the nerves. Methods: We included fifty-eight patients, all suspected of either ALS, polyneuropathy or myopathy. We measured the CSA of the median and ulnar nerve at brachial and antebrachial level, bilaterally. We calculated inter nerve and intra nerve ratio for both nerves. Fifteen were later diagnosed with ALS thus included and invited to follow-up examination 3 months later. Only nine patients showed up to follow up. We recruited a control group of 38 HS. Results: We found no difference in mean CSA of the median nerve and ulnar nerve at the brachial and antebrachial level between ALS patients and HS. We found an increase of mean CSA of both nerves at the antebrachial level at three month follow up, median nerve baseline 0.053 (0.017), median nerve follow-up 0.068 (0.016); p = 0.01, ulnar nerve baseline 0.044 (0.017), ulnar nerve follow-up 0.050 (0.017); p = 0.048. Conclusion: CSA of the peripheral nerves could not differentiate the ALS group from the HS. At follow up, we found an unexpected increase of the CSA in ALS patients.
Abstracts / Clinical Neurophysiology 128 (2017) e178–e303
of GBS. Whereas AIDP patients generally have proximally enlarged nerves in the ultrasound, our AMAN-patient showed a distally enlarged median nerve, possibly related to the distal conduction failure.
Keywords: AMAN, Axonal conduction blocks, Nerve ultrasound doi:10.1016/j.clinph.2017.07.236
P229 Peripheral nerve injury after nerve blockade—Nils Wolfram, Janus Kaufmann Lindquist, Martin Lauritzen (Rigshospitalet Glostrup, Clinical Neurophysiology, Copenhagen, Denmark) Objectives: Nerve blockade is a common procedure in peripheral limb surgery. In some cases however the anesthesia is directly followed by distally paresis and/or sensory disturbance. Method: We describe the neurophysiological and ultasonographic findings of 5 cases in this patient group. Results: 5 patients were examined clinically, neurophysiologically and with ultrasonography. All patients had permanent paresis and/or sensory disturbance proximal to the site of surgery and distal to the site of peripheral nerve blockade. Neurophysiological findings showed markedly side-difference of motor – and sensory amplitudes suggesting axonal degeneration. Ultrasonography showed increased cross-sectional area/long-axis diameter of affected nerves and changes in intraneural and epineural structures at site of local anesthesia injection. Discussion: Nerve injury following peripheral nerve blockade is a well-known complication, but the mechanisms are not well understood, specifically and ultrasonographic data are not yet available. Our series of patients showed axonal disturbance in several nerves distal to the site of peripheral nerve blockade. Ultrasonography showed morphological nerve changes at the side of anesthesia placement. Conclusions: Peripheral nerve anesthesia may cause axonal motor and sensory nerve degeneration distally to anesthesia placement. Ultrasonographic changes in the nerve are mostly present at the site of anesthesia placement. Significance: Peripheral nerve injury after nerve blockade has been described previously but the mechanisms are not understood - neurophysiological and ultrasonographic examinations are valuable and may contribute to an understanding of desease mechanisms. Our study may be of help in assessing the safety of local anesrhetics and potentially prevent persistent side-effects and nerve injury following the use of local anesthesia for limb surgery.
Keywords: Peripheral nerve injury, Nerve blockade, Neurophysiology, Ultrasound doi:10.1016/j.clinph.2017.07.237
P230 Ulnar epineural discontinuity and electrophysiological changes in a young girl following ulnar fracture—Janus Kaufmann Lindqvist, Nils Wolfram (University of Copenhagen, Department of Clinical Neurophysiology, Glostrup, Denmark) Objectives: Electrophysiologic evaluation of traumatic peripheral nerve lesions can be complicated, especially in children where the given diagnosis can have dire consequences especially if not accurate.
Method: electrophysiological and sonographic consecutive examinations during a timelapse of 2 years (4 examinations). Results: A 10 year old girl developed a severe ulnar neuropathy following a fracture of both forearm bones. Electrophysiology resembled complete denervation without any motoric or sensory answers. EMG revealed spontaneous activity in the interosseous dorsalis 1 muscle in the affected arm. Sonography visualized the nerve with an epineural defect but in continuity. We followed the girl in a timespace over 2 years with a total of 4 examinations. As the epineural defect diminished the electrophysiologic changes recovered. At the 4 examination the sonographic appearance was normalized except a slight neuroma at the lesion site. Discussion: Decision making following traumatic nerve lesions relies heavily on electrodiagnostic testing. In this case we have shown that an epineural defect can ‘‘mimick” nerve discontinuity electrophysiologic. Sonography revealed the nerve in continuity and the nerve function slowly regained following the recovery of the epineurium. Conclusions: Epineural defects can have an electrophysiological appearance resembling complete denervation in the recovery period. If sonography shows nerve continuity a conservative approach could be recommended. Significance: Sonography can help along with electrophysiology in differentiating between severed nerves and nerve changes electrophysiologically resembling complete denervation. The case could argue that sonography should be performed in all traumatic nerve lesions.
Keywords: Peripheral nerve injury, Traumatic nerve injury, Neurophysiology, Sonography doi:10.1016/j.clinph.2017.07.238
P231 High resolution ultrasound of peripheral nerves in amyotrophic lateral sclerosis—Erisela Qerama, Simon Østergaard Wehrs, Sara Silkær Bak *, Maria Thelin Johansson, Anders Fuglsang-Frederiksen (Aarhus University Hospital, Department of Neurophysiology, Aarhus, Denmark)
Introduction: In this study we examined whether the ultrasound (UL) measurement of median and ulnar nerves are different in ALS patients compared with healthy subjects(HS) and whether US can be used to demonstrate the progressive axonal loss by showing decrease in cross-sectional area (CSA) of the nerves. Methods: We included fifty-eight patients, all suspected of either ALS, polyneuropathy or myopathy. We measured the CSA of the median and ulnar nerve at brachial and antebrachial level, bilaterally. We calculated inter nerve and intra nerve ratio for both nerves. Fifteen were later diagnosed with ALS thus included and invited to follow-up examination 3 months later. Only nine patients showed up to follow up. We recruited a control group of 38 HS. Results: We found no difference in mean CSA of the median nerve and ulnar nerve at the brachial and antebrachial level between ALS patients and HS. We found an increase of mean CSA of both nerves at the antebrachial level at three month follow up, median nerve baseline 0.053 (0.017), median nerve follow-up 0.068 (0.016); p = 0.01, ulnar nerve baseline 0.044 (0.017), ulnar nerve follow-up 0.050 (0.017); p = 0.048. Conclusion: CSA of the peripheral nerves could not differentiate the ALS group from the HS. At follow up, we found an unexpected increase of the CSA in ALS patients.