title: [Assessment of patient movement in interventional procedures using electromagnetic detection - comparison between conventional fixation and vacuum mattress].
abstract: OBJECTIVE
  To assess patient movement on a vacuum mattress compared to a standard viscoelastic mattress during interventional procedures using an electromagnetic tracking device.
  
  
  METHODS
  In 17 consecutive patients who underwent a diagnostic or interventional procedure, the patient was positioned using a vacuum mattress (VL, n = 9) or a standard viscoelastic mattress (SL, n = 8). The patient position was recorded continuously after the start of the procedure (S) using an electromagnetic navigation device. After the intervention (E), patients were asked to lift up the upper part of the body and to lie down again (repositioning maneuver, P). Based on the recorded patient positions, the patient movement (PM) at rest ΔP(SE), PM due to the repositioning maneuver ΔP(EP), total PM ΔP(SP) and maximum PM during the intervention ΔPMax(SE) were calculated.
  
  
  RESULTS
  Using VL, PM at rest (ΔP[SE]: VL: 4.3 ± 2.8 mm, SL: 17.1 ± 15.7 mm; p = 0.036) and total PM (ΔP[SP]: VL: 4.6 mm ± 2.5 ± mm, SL: 27.8 ± 19.6 mm; p = 0.002) were significantly smaller. In contrast, the maximum PM as a parameter for the mobility of the patient (ΔPMax(SE): VL: 14.2 ± 15.1 mm, SL: 17.6 ± 13.4 mm; p = 0.48) and the PM due to the repositioning maneuver (ΔP[EP]: VL: 4.4 ± 2.5 mm, SL: 15.7 mm ± 15.9 mm, p = 0.32) were similar.
  
  
  CONCLUSIONS
  Patient positioning on a vacuum mattress is fast, easy, comfortable for the patient and reduces relevant patient movements. Therefore, vacuum mattress positioning can be used for image-guided interventions relying on preprocedural imaging data, where minimal patient movement is a prerequisite.
authors.affiliation: Zentrum für Diagnostische und Interventionelle Radiologie und Nuklearmedizin, Campus Benjamin Franklin, Charité - Universitätsmedizin Berlin, Berlin. cmallmann@gmx.de
authors.forename: C
authors.initials: C
authors.lastname: Mallmann
authors.forename: K-J
authors.initials: KJ
authors.lastname: Wolf
authors.forename: F K
authors.initials: FK
authors.lastname: Wacker
authors.forename: B C
authors.initials: BC
authors.lastname: Meyer
mesh_terms: D000368:Aged; D015901:Angiography, Digital Subtraction / Q000295:instrumentation*; D017130:Angioplasty / Q000295:instrumentation*; D016477:Artifacts; D001513:Beds; D016461:Chemoembolization, Therapeutic / Q000295:instrumentation*; D055590:Electromagnetic Phenomena; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation*; D021621:Imaging, Three-Dimensional / Q000295:instrumentation*; D007103:Immobilization / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D056888:Patient Positioning / Q000295:instrumentation*; D019047:Phantoms, Imaging; D011677:Punctures / Q000295:instrumentation; D015642:Radiology, Interventional / Q000295:instrumentation*; D013996:Time and Motion Studies; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*