Abstract
Purpose
Somatosensory evoked potential (SSEP) monitoring using the median nerve (MN) modality during carotid endarterectomy is well established. This study assessed the usefulness of monitoring the posterior tibial nerve (PTN) SSEP as an adjunct to MNSSEP for detection of cerebral ischemia and as an indicator for the insertion of a shunt in patients undergoing a carotid endarterectomy.
Methods
All patients undergoing carotid endarterectomy during three years who had routine bilateral MNSSEP were also monitored with bilateral PTNSSEP. Patients received a shunt if there was a significant change (> 50% decrease in amplitude of cortical peak (N20) in the MNSSEP after cross clamping. The incidence, timing, and duration of all PTNSSEP changes were compared to MNSSEP changes.
Results
One hundred fifty-three patients were studied. Significant changes in MNSSEP after cross clamp lead to insertion of a shunt in six patients. Changes in PTNSSEP occurred at almost the same time in three patients, four minutes before MNSSEP in one, three minutes later in one and no change in one patient. Good quality baseline tracings were obtained in 99% MNSSEP as compared to 88% PTNSSEP (P < 0.05). New postoperative neurological deficits occurred in four patients (2.6%), only one had significant evoked potential changes.
Conclusion
Monitoring of PTNSSEP is feasible and may be considered for an adjunct to MNSSEP or as an alternative modality if there are difficulties with MNSSEP. However, there may be a greater incidence of poor quality baseline tracings for PTNSSEP.
Résumé
Objectif
Le monitorage du potentiel évoqué somato-sensitif (PESS) selon la modalité du nerf médian (NM) pendant l’endartériectomie de la carotide est bien connu. Nous voulions évaluer l’utilité du monitorage du PESS du nerf tibial postérieur (NTP) comme complément au PESSNM pour la détection d’ischémie cérébrale et comme indicateur pour l’insertion d’un shunt pendant une endartériectomie de la carotide.
Méthode
Pendant trois ans, les patients devant subir une endartériectomie carotidienne et qui avaient un PESSNM de routine ont aussi eu un PESSNTP bilatéral. Ils ont reçu un shunt s’il y avait un changement significatif (> 50 % de diminution de l’amplitude du pic cortical (N20) du PESSNM après le clampage carotidien. L’incidence, l’ordre de déroulement et la durée des changements de PESSNTP et de PESSNM ont été comparés.
Résultats
L’étude a porté sur 153 patients. Des changements significatifs de PESSNM survenus après le clampage croisé ont mené à l’insertion d’un shunt chez six patients. Des changements de PESSNTP sont survenus presque au même moment chez trois patients, quatre minutes avant le PESSNM chez un patient, trois minutes après chez un autre et aucun changement n’a été noté chez un troisième. Des tracés de base de bonne qualité ont été obtenus chez 99 % des PESS-NM comparés à 88% de PESSNTP (P < 0,05). De nouveaux déficits neurologiques postopératoires ont été observés chez quatre patients (2,6 %) dont un seulement présentait des changements significatifs de potentiel évoqué.
Conclusion
Le monitorage du PESSNTP est faisable et peut être considéré comme complément du PESSNM ou comme une modalité de remplacement devant des difficultés de PESSNM. Toutefois, il pourrait y avoir une plus forte incidence de tracés de base de pauvre qualité pour le PESSNTP.
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References
Markand ON, Dilley RS, Moorthy SS, Warren C Jr. Monitoring of somatosensory evoked responses during carotid endarterectomy. Arch Neurol 1984; 41: 375–8.
Schweiger H, Kamp HD, Dinkel M. Somatosensoryevoked potentials during carotid artery surgery: experience in 400 operations. Surgery 1991; 109: 602–9.
Lam AM, Manninen PH, Ferguson GG, Nantau W. Monitoring electrophysiologic function during carotid endarterectomy: a comparison of somatosensory evoked potentials and conventional electroencephalogram. Anesthesiology 1991; 75: 15–21.
Haupt WF, Horsch S. Evoked potential monitoring in carotid surgery: a review of 994 cases. Neurology 1992; 42: 835–8.
Amantini A, Bartelli M, de Scisciolo G, et al. Monitoring of somatosensory evoked potentials during carotid endarterectomy. J Neurol 1992; 239: 241–7.
Fava E, Bortolani E, Ducati A, Schieppati M. Role of SEP in identifying patients requiring temporary shunt during carotid endarterectomy. Electroencephalogr Clin Neurophysiol 1992; 84: 426–32.
D’Addato M, Pedrini L, Vitacchiano G. Intraoperative cerebral monitoring in carotid surgery. Eur J Vasc Surg 1993; 7(Suppl A): 16–20.
Fiori L, Parenti G. Electrophysiological monitoring for selective shunting during carotid endarterectomy. J Neurosurg Anesthesiol 1995; 7: 168–73.
Horsch S, Ktenidis K. Intraoperative use of somatosensory evoked potentials for brain monitoring during carotid surgery. Neurosurg Clin N Am 1996; 7: 693–702.
Prokop A, Meyer GP, Walter M, Erasmi H. Validity of SEP monitoring in carotid surgery. J Cardiovasc Surg 1996; 37: 337–42.
Schwartz ML, Panetta TF, Kaplan BJ, et al. Somatosensory evoked potential monitoring during carotid surgery. Cardiovasc Surg 1996; 4: 77–80.
Guérit JM, Witdoeckt C, de Tourtchaninoff M, et al. Somatosensory evoked potential monitoring in carotid surgery. I. Relationships between qualitative SEP alterations and intraoperative events. Electroencephalogr Clin Neurophysiol 1997; 104: 459–69.
Wöber C, Zeitlhofer J, Asenbaum S, et al. Monitoring of median nerve somatosensory evoked potentials in carotid surgery. J Clin Neurophysiol 1998; 15: 429–38.
Pedrini L, Tarantini S, Cirelli MR, Ballester A, Cifiello BI, D’Addato M. Intraoperative assessment of cerebral schaemia during carotid surgery. Int Angiol 1998; 17: 10–4.
Linstedt U, Maier C, Petry A. Intraoperative monitoring with somatosensory evoked potentials in carotid artery surgery — less reliable in patients with preoperative neurologic deficiency? Acta Anaesthesiol Scand 1998; 42: 13–6.
Manninen PH, Tan TK, Sarjeant RM. Somatosensory evoked potential monitoring during carotid endarterectomy in patients with a stroke. Anesth Analg 2001; 93: 39–44.
Sbarigia E, Schioppa A, Misuraca M, et al. Somatosensory evoked potentials versus locoregional anaesthesia in the monitoring of cerebral function during carotid artery surgery: preliminary results of a prospective study. Eur J Vasc Endovasc Surg 2001; 21: 413–6.
Sako K, Nakai H, Kawata Y, Takizawa K, Satho M, Yonemasu Y. Temporary arterial occlusion during anterior communicating or anterior cerebral artery aneurysm operation under tibial nerve somatosensory evoked potential monitoring. Surg Neurol 1998; 49: 316–23.
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Manninen, P., Sarjeant, R. & Joshi, M. Posterior tibial nerve and median nerve somatosensory evoked potential monitoring during carotid endarterectomy. Can J Anesth 51, 937–941 (2004). https://doi.org/10.1007/BF03018896
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DOI: https://doi.org/10.1007/BF03018896