title: High frequency ultrasound sacral images in the critically ill: Tissue characteristics versus visual evaluation.
abstract: OBJECTIVE
  High frequency ultrasound (HFUS) systems may identify tissue injury. We compared HFUS tissue characteristics (dermal thickness and dermal density) with visual image examination.
  
  
  METHODS
  Longitudinal study in critically ill mechanically ventilated adults, from three ICUs (Surgical Trauma, Medical Respiratory, Neuroscience) enrolled within 24hours of airway intubation. Sacral HFUS images were obtained daily for up to seven days. Expert evaluation of the best image per day was completed and compared to HFUS generated tissue characteristics (dermal thickness and dermal density).
  
  
  RESULTS
  Of the113 subjects with 1614 comparisons analysed, 73.2% to 84% were normal, and 6.3% to 11.8% of the comparisons had injury present but no change was noted in the injury observed. There were no significant differences in one-day comparisons among type of injury and mean dermal thickness (p=0.6645) or dermal median intensity (adjusted p=0.06-0.17). All other day-to-day comparisons were similarly non-significant.
  
  
  CONCLUSIONS
  We found no association among dermal density, dermal thickness and visual examination of changes in sacral HFUS images for any day-to-day comparison. The use of sacral HFUS as a screening tool for the development of tissue injury is in its infancy. Additional comparative studies should be conducted to identify its future clinical usefulness.
authors.affiliation: Adult Health and Nursing Systems, Department of the School of Nursing, Virginia Commonwealth University, Richmond, VA, United States. Electronic address: mjgrap@vcu.edu.
authors.forename: Mary Jo
authors.initials: MJ
authors.lastname: Grap
authors.affiliation: Department of Mathematics and Statistics, Air Force Institute of Technology, Wright-Patterson Air Force Base, Dayton, OH, United States.
authors.forename: Christine M
authors.initials: CM
authors.lastname: Schubert
authors.affiliation: Adult Health and Nursing Systems, Department of the School of Nursing, Virginia Commonwealth University, Richmond, VA, United States.
authors.forename: Ruth S
authors.initials: RS
authors.lastname: Burk
authors.affiliation: Department of Surgery, Virginia Commonwealth University Heath System, Richmond, VA, United States.
authors.forename: Valentina
authors.initials: V
authors.lastname: Lucas
authors.affiliation: Biomedical Engineering Department, School of Engineering, Virginia Commonwealth University, Richmond, VA, United States.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Wetzel
authors.affiliation: Biomedical Engineering Department, School of Engineering, Virginia Commonwealth University, Richmond, VA, United States.
authors.forename: Anathea
authors.initials: A
authors.lastname: Pepperl
authors.affiliation: University of South Florida, Tampa, FL, United States.
authors.forename: Cindy L
authors.initials: CL
authors.lastname: Munro
mesh_terms: D018806:APACHE; D000328:Adult; D000368:Aged; D016638:Critical Illness / Q000628:therapy*; D056228:Feedback, Sensory; D005260:Female; D006801:Humans; D007103:Immobilization / Q000009:adverse effects; D007362:Intensive Care Units / Q000458:organization & administration; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D000078702:Radiofrequency Therapy; D012121:Respiration, Artificial / Q000009:adverse effects; D012445:Sacrococcygeal Region / Q000000981:diagnostic imaging / Q000293:injuries*; D013046:Specific Gravity; D014463:Ultrasonography / Q000592:standards*
keywords: Critical care; Evaluation; High frequency ultrasound; Pressure ulcers