title: Ultrasonographic confirmation of intraosseous needle placement in an adult unembalmed cadaver model.
abstract: OBJECTIVE
  Intraosseous access is widely used in pediatric and adult resuscitations when vascular access cannot be promptly established. Confirmation of intraosseous needle placement has traditionally relied on the ability to aspirate blood or marrow or infuse crystalloid easily. This study's aim is to determine the value of bedside ultrasonography as a means of confirming intraosseous needle placement by visualizing the flow of crystalloid within the intraosseous space.
  
  
  METHODS
  A controlled trial was conducted in which intraosseous access was obtained in the bilateral distal tibia of 4 freshly frozen, unembalmed cadavers. In 8 legs, an intraosseous needle (15-gauge Jamshidi) was inserted 1 fingerbreadth superior to the medial malleolus and flushed with 10 mL of crystalloid. Measurements included whether crystalloid was observed to flow by gravity into the drip reservoir of the intravenous tubing and whether color flow was visualized within the intraosseous space of the tibia with a 5- to 10-MHz linear transducer in color power Doppler mode, positioned just cephalad to the intraosseous needle. Intraosseous needles were then intentionally placed into the subcutaneous space just posterior to the distal tibia, and these measurements were repeated. Two blinded observers reviewed ultrasonographic video recordings and rated the presence or absence of color flow within the intraosseous space.
  
  
  RESULTS
  Intraosseous color flow on ultrasonography correctly identified all placements, but flow into the drip reservoir was incorrect for one of the intraosseous lines (P=1.0 versus ultrasonography) and 6 of the subcutaneous lines (P=0.31 versus ultrasonography). There was perfect interobserver agreement (kappa=1) during video review.
  
  
  CONCLUSIONS
  In freshly frozen cadavers, ultrasonographic visualization of flow within the intraosseous space may be a reliable method of confirming intraosseous placement. The observation of flow into the drip reservoir appears to be an unreliable indicator of intraosseous placement in fresh frozen cadavers.
authors.affiliation: Division of Emergency Medicine, University of Medicine and Dentistry of New Jersey, Newark, NJ 07103, USA. stonemd@mac.com
authors.forename: Michael B
authors.initials: MB
authors.lastname: Stone
authors.forename: Nathan A
authors.initials: NA
authors.lastname: Teismann
authors.forename: Ralph
authors.initials: R
authors.lastname: Wang
mesh_terms: D000328:Adult; D002102:Cadaver; D000077324:Crystalloid Solutions; D004615:Embalming; D006112:Gravitation; D006801:Humans; D017148:Infusions, Intraosseous; D007552:Isotonic Solutions / Q000008:administration & dosage*; D009339:Needles; D011897:Random Allocation; D013977:Tibia / Q000000981:diagnostic imaging; D018615:Ultrasonography, Doppler, Color
chemical_list: D000077324:Crystalloid Solutions; D007552:Isotonic Solutions