title: Primary Care Management of Skin Abscesses Guided by Ultrasound.
abstract: BACKGROUND
  Primary care providers often manage skin abscesses in the outpatient setting. Estimating the size and depth of an abscess, and distinguishing abscess from cellulitis by clinical examination can be challenging due to surrounding firm tissue induration. Definitive treatment of abscess requires incision and drainage, and the approach chosen may be altered by abscess size, depth, and surrounding neurovascular structures.
  
  
  METHODS
  For 31 consecutive patients seen in the primary care outpatient clinic, we prospectively compared the estimated size of skin abscesses by clinical examination with that determined by ultrasound. Prior to incision and drainage, a limited point-of-care ultrasound examination was performed and the abscess dimensions were measured, the depth was determined, and adjacent vascular structures were noted. Based on ultrasound findings, physicians reported whether the decision to perform the procedure or the techniques used to perform the procedure were altered by the scan.
  
  
  RESULTS
  The clinical examination was inaccurate for size estimation by >0.5 cm in 16 of 31 patients (52%). Ultrasound examination changed the physician decision of whether or not incision and drainage should be performed in 7 patients (23%) and altered the technique/approach in an additional 10 patients (32%); thus, management was changed in 55% of cases. Physician confidence in performing the procedure was improved in 16 cases (52%).
  
  
  CONCLUSIONS
  Outpatient procedural management of skin abscesses by primary care physicians was altered in more than half the cases by performing point-of-care ultrasound prior to incision and drainage.
authors.affiliation: Division of Primary Care Internal Medicine, Department of Medicine, Mayo Clinic, Rochester, Minn. Electronic address: Greenlund.Laura@Mayo.edu.
authors.forename: Laura J S
authors.initials: LJS
authors.lastname: Greenlund
authors.affiliation: Department of Family Medicine, Mayo Clinic, Rochester, Minn.
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Merry
authors.affiliation: Department of Family Medicine, Mayo Clinic, Rochester, Minn.
authors.forename: Tom D
authors.initials: TD
authors.lastname: Thacher
authors.affiliation: Division of Primary Care Internal Medicine, Department of Medicine, Mayo Clinic, Rochester, Minn.
authors.forename: William J
authors.initials: WJ
authors.lastname: Ward
mesh_terms: D000038:Abscess / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery*; D002481:Cellulitis / Q000175:diagnosis; D000066491:Clinical Decision-Making; D003937:Diagnosis, Differential; D004322:Drainage; D006801:Humans; D019095:Point-of-Care Systems; D011320:Primary Health Care; D011446:Prospective Studies; D012871:Skin Diseases / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery*; D014463:Ultrasonography
keywords: Abscess; Management; Skin; Ultrasound