title: Ultrasound investigation of leg position to enhance femoral vein exposure for cannulation.
abstract: BACKGROUND
  Femoral venous access is an essential part of patient care in the emergency department (ED). However, current medical literature and texts have not dealt with it much using actual patient anatomy.
  
  
  OBJECTIVE
  This study aimed to show that manipulation of the lower extremities may alter the anatomy to a more favorable position for cannulation.
  
  
  METHODS
  Ultrasound examination was conducted on a prospective sample of ED patients to evaluate anatomical variance of the femoral artery and vein overlap as well as the change in femoral vein diameter with leg position. Bilateral measurements of the diameter of the vein were taken at three different leg positions (straight, abduction, and abduction with external rotation).
  
  
  RESULTS
  This study enrolled a total of 132 ED patients. Of these, 122 (92%) patients showed some degree of overlap on the right and 126 (95%) patients showed some degree of overlap on the left. There was a statistically significant decrease in the percentage of overlap when moving the leg from a straightened position to an abducted position, and an additional decrease when moving the leg into an abducted and externally rotated position. There was also a statistically significant increase in the size of the femoral vein with each of these positions.
  
  
  CONCLUSIONS
  Up to 95% of people have some degree of overlap of the femoral vein by the femoral artery. By positioning the leg in an abducted and externally rotated position, the amount of overlap is reduced and the diameter of the vein is increased, maximizing the percentage of the vein available for cannulation.
authors.affiliation: Emergency Department, Affinity Medical Center, Massillon, Ohio; Ohio University Heritage College of Osteopathic Medicine, Athens, Ohio.
authors.forename: Craig
authors.initials: C
authors.lastname: Randall
authors.affiliation: Emergency Department, Affinity Medical Center, Massillon, Ohio; Ohio University Heritage College of Osteopathic Medicine, Athens, Ohio.
authors.forename: Erik
authors.initials: E
authors.lastname: Schmeiser
authors.affiliation: Emergency Department, Affinity Medical Center, Massillon, Ohio; Ohio University Heritage College of Osteopathic Medicine, Athens, Ohio.
authors.forename: Emily
authors.initials: E
authors.lastname: Fiers
authors.affiliation: Emergency Department, Affinity Medical Center, Massillon, Ohio; Ohio University Heritage College of Osteopathic Medicine, Athens, Ohio.
authors.forename: Andrew
authors.initials: A
authors.lastname: Little
authors.affiliation: Ohio University Heritage College of Osteopathic Medicine, Athens, Ohio.
authors.forename: Godwin
authors.initials: G
authors.lastname: Dogbey
authors.affiliation: Emergency Department, Affinity Medical Center, Massillon, Ohio; Ohio University Heritage College of Osteopathic Medicine, Athens, Ohio.
authors.forename: Gary
authors.initials: G
authors.lastname: Richardson
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D002405:Catheterization, Central Venous / Q000379:methods*; D005260:Female; D005268:Femoral Vein / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D006801:Humans; D007866:Leg / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D056888:Patient Positioning / Q000379:methods*; D011446:Prospective Studies; D014463:Ultrasonography
keywords: central venous access; femoral vein position; ultrasound