title: Severe cerebral desaturation during shoulder arthroscopy in the beach-chair position.
abstract: During shoulder arthroscopy in the beach-chair position, cerebral ischemia may be a serious complication because prolonged hypotension may affect regional cerebral oxygen supply. We present the cases of 2 patients in whom a reduction in mean arterial pressure after anesthesia provoked a decrease in frontal lobe oxygenation to below the level that causes presyncopal symptoms in the awake subject. In the healthy middle-aged patient, cerebral oxygenation decreased by approximately 40%, indicating that cerebral blood flow was markedly reduced, and intravenous administration of ephedrine rapidly restored cerebral oxygenation. During surgery in the beach-chair position, hypotension must be avoided, and in all patients regional, cerebral oxygenation should be monitored and optimized.
authors.affiliation: Department of Orthopedic Surgery, Køge Hospital, Køge, Denmark. Christiandippmann@gmx.de
authors.forename: Christian
authors.initials: C
authors.lastname: Dippmann
authors.forename: Søren
authors.initials: S
authors.lastname: Winge
authors.forename: Henning Bay
authors.initials: HB
authors.lastname: Nielsen
mesh_terms: D000768:Anesthesia, General / Q000009:adverse effects*; D001182:Arthroscopy; D001785:Blood Gas Monitoring, Transcutaneous; D002545:Brain Ischemia / Q000175:diagnosis / Q000188:drug therapy / Q000209:etiology* / Q000517:prevention & control; D002560:Cerebrovascular Circulation / Q000187:drug effects / Q000502:physiology; D004809:Ephedrine / Q000627:therapeutic use; D005625:Frontal Lobe / Q000098:blood supply; D006801:Humans; D007022:Hypotension / Q000139:chemically induced* / Q000150:complications; D002534:Hypoxia, Brain / Q000175:diagnosis / Q000188:drug therapy / Q000209:etiology* / Q000517:prevention & control; D007431:Intraoperative Complications / Q000175:diagnosis / Q000188:drug therapy / Q000209:etiology* / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D010880:Piperidines / Q000009:adverse effects; D011187:Posture; D015742:Propofol / Q000009:adverse effects; D000077208:Remifentanil; D017006:Rotator Cuff / Q000601:surgery*; D000070636:Rotator Cuff Injuries
chemical_list: D010880:Piperidines; D004809:Ephedrine; D000077208:Remifentanil; D015742:Propofol