title: Somatosensory evoked potential monitoring used to compare the effect of three asymmetric sternal retractors on brachial plexus function.
abstract: We compared the effect of three different asymmetric sternal retractors on brachial plexus dysfunction using intraoperative somatosensory evoked potentials (SSEPs). We studied 60 patients undergoing coronary bypass and internal mammary harvest. Assessment of brachial plexus function was performed pre- and postoperatively. Patients were assigned the use of a Pittman (MN Scientific Instruments Inc., Minneapolis, MN), Rultract (Rultract Inc., Cleveland, OH), or Delacroix-Chevalier (Delacroix-Chevalier, Paris, France) asymmetric sternal retractor for internal mammary exposure. SSEP changes from baseline during asymmetric retractor use and removal were determined, and average changes were compared among the retractor groups. Patient demographics and baseline SSEP values were similar. Fewer patients in the Delacroix-Chevalier group had decreases in SSEP amplitudes after retractor placement. Of the patients in the Rultract and Pittman groups, 45% and 25%, respectively, had amplitude decreases of >50%, compared with only 5% of the Delacroix-Chevalier patients. Three patients in both the Pittman and Rultract groups and one patient in the Delacroix-Chevalier group suffered brachial plexus symptoms postoperatively. We conclude that the Delacroix-Chevalier retractor is associated with less neurophysiologic evidence of brachial plexus dysfunction during asymmetric sternal retraction compared with either the Pittman or Rultract sternal retractors.
  
  
  CONCLUSIONS
  We used somatosensory evoked potentials to assess the effect of several different asymmetric sternal retractors on brachial plexus dysfunction and to determine which produced the least evidence of nerve damage during surgical exposure of the internal mammary artery.
authors.affiliation: Department of Anesthesiology, Loyola University Medical Center, Maywood, Illinois 60153, USA.
authors.forename: W S
authors.initials: WS
authors.lastname: Jellish
authors.forename: B
authors.initials: B
authors.lastname: Blakeman
authors.forename: P
authors.initials: P
authors.lastname: Warf
authors.forename: S
authors.initials: S
authors.lastname: Slogoff
mesh_terms: D001794:Blood Pressure; D001917:Brachial Plexus / Q000293:injuries / Q000503:physiopathology*; D001026:Coronary Artery Bypass; D004562:Electrocardiography; D004568:Electrodiagnosis / Q000295:instrumentation; D004867:Equipment Design; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005500:Follow-Up Studies; D006801:Humans; D007431:Intraoperative Complications / Q000517:prevention & control; D008323:Mammary Arteries / Q000601:surgery; D008475:Median Nerve / Q000503:physiopathology; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D010292:Paresthesia / Q000209:etiology; D011183:Postoperative Complications; D011930:Reaction Time; D012678:Sensation Disorders / Q000209:etiology; D013249:Sternum / Q000601:surgery*; D013908:Thoracotomy / Q000009:adverse effects / Q000295:instrumentation*