title: Bevel direction of epidural needles reliably predicts direction of catheter placement and contrast spread in human cadavers: results of a pilot study.
abstract: OBJECTIVE
  To confirm the relationship between bevel orientation, catheter direction, and radiopaque contrast spread in the lumbar region.
  
  
  METHODS
  Pilot cadaver study.
  
  
  METHODS
  Anatomy laboratory of a university hospital.
  
  
  METHODS
  Cadavers were randomized to two groups of 4 cadavers each. In Group 1, needle bevel direction at epidural entry was cephalad; in Group 2, it was caudad. After placement of each epidural catheter in L4-L5 interspace, 2 mL of radiopaque contrast was injected and a lumbar posterior-anterior radiograph was obtained. Catheter direction and direction of radiopaque contrast spread were collected.
  
  
  RESULTS
  Due to the inability to access the epidural space secondary to surgical changes in the lumbar spine, one cadaver in the cephalad group was excluded. In 7 of 7 (100%) cadavers, the catheter tip direction according to the radiograph corresponded directly with bevel direction.
  
  
  CONCLUSIONS
  A strong relationship exists between bevel orientation and catheter direction; however, catheter position does not reliably predict the direction in which the injected fluid spreads in all cadavers.
authors.affiliation: Department of Anesthesiology, Montefiore Medical Center-Albert Einstein College of Medicine, Bronx, NY 10467, USA.
authors.forename: Naum
authors.initials: N
authors.lastname: Shaparin
authors.affiliation: Department of Anesthesiology, Montefiore Medical Center-Albert Einstein College of Medicine, Bronx, NY 10467, USA. Electronic address: jbernste@montefiore.org.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Bernstein
authors.affiliation: Montefiore Medical Center-Albert Einstein College of Medicine, Bronx, NY 10467, USA.
authors.forename: Robert S
authors.initials: RS
authors.lastname: White
authors.affiliation: Department of Anesthesiology, Rutgers-New Jersey Medical School, 185 South Orange Avenue, Newark, NJ 07103, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Kaufman
mesh_terms: D000767:Anesthesia, Epidural / Q000295:instrumentation / Q000379:methods; D002102:Cadaver; D002404:Catheterization / Q000295:instrumentation / Q000379:methods*; D003287:Contrast Media / Q000008:administration & dosage* / Q000493:pharmacokinetics; D004824:Epidural Space; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae; D009339:Needles; D010865:Pilot Projects
chemical_list: D003287:Contrast Media
keywords: Contrast spread; Epidural catheter placement; Human cadavers; Needle bevel direction