title: Changes in cardiac index and blood pressure on positioning children prone for scoliosis surgery.
abstract: In this prospective observational study we investigated the changes in cardiac index and mean arterial pressure in children when positioned prone for scoliosis correction surgery. Thirty children (ASA 1-2, aged 13-18 years) undergoing primary, idiopathic scoliosis repair were recruited. The cardiac index and mean arterial blood pressure (median (IQR [range])) were 2.7 (2.3-3.1 [1.4-3.7]) l.min(-1).m(-2) and 73 (66-80 [54-91]) mmHg, respectively, at baseline; 2.9 (2.5-3.2 [1.7-4.4]) l.min(-1).m(-2) and 73 (63-81 [51-96]) mmHg following a 5-ml.kg(-1) fluid bolus; and 2.5 (2.2-2.7 [1.4-4.8]) l.min(-1).m(-2) and 69 (62-73 [46-85]) mmHg immediately after turning prone. Turning prone resulted in a median reduction in cardiac index of 0.5 l.min(-1).m(-2) (95% CI 0.3-0.7 l.min(-1).m(-2), p=0.001), or 18.5%, with a large degree of inter-subject variability (+10.3% to -40.9%). The changes in mean arterial blood pressure were not significant. Strategies to predict, prevent and treat decreases in cardiac index need to be developed.
authors.affiliation: Department of Anesthesiology, Pharmacology & Therapeutic, The University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Z E
authors.initials: ZE
authors.lastname: Brown
authors.forename: M
authors.initials: M
authors.lastname: Görges
authors.forename: E
authors.initials: E
authors.lastname: Cooke
authors.forename: S
authors.initials: S
authors.lastname: Malherbe
authors.forename: G A
authors.initials: GA
authors.lastname: Dumont
authors.forename: J M
authors.initials: JM
authors.lastname: Ansermino
mesh_terms: D000293:Adolescent; D062186:Arterial Pressure / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology*; D002302:Cardiac Output / Q000502:physiology*; D002648:Child; D017548:Echocardiography, Transesophageal; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D016343:Monitoring, Intraoperative; D019637:Orthopedic Procedures / Q000379:methods; D056888:Patient Positioning; D016684:Prone Position / Q000502:physiology; D011446:Prospective Studies; D012600:Scoliosis / Q000601:surgery*; D013318:Stroke Volume / Q000502:physiology