title: Needle thoracostomy in the treatment of a tension pneumothorax in trauma patients: what size needle?
abstract: BACKGROUND
  A tension pneumothorax requires immediate decompression using a needle thoracostomy. According to advanced trauma life support guidelines this procedure is performed in the second intercostal space (ICS) in the midclavicular line (MCL), using a 4.5-cm (2-inch) catheter (5-cm needle). Previous studies have shown a failure rate of up to 40% using this technique. Case reports have suggested that this high failure rate could be because of insufficient length of the needle.
  
  
  OBJECTIVE
  To analyze the average chest wall thickness (CWT) at the second ICS in the MCL in a trauma population and to evaluate the length of the needle used in needle thoracostomy for emergency decompression of tension pneumothoraces.
  
  
  METHODS
  Retrospective review of major trauma admissions (Injury Severity Score >12) at the Foothills Medical Centre in Calgary, Canada, who underwent a computed tomography chest scan admitted in the period from October 2001 until March 2004. Subgroup analysis on men and women, <40 years of age and >/=40 years of age was defined a priori. CWT was measured to the nearest 0.01 cm at the second ICS in the MCL.
  
  
  RESULTS
  The mean CWT in the 604 male patients and 170 female patients studied averaged 3.50 cm at the left second ICS MCL and 3.51 cm on the right. The mean CWT was significantly higher for women than men (p < 0.0001). About 9.9% to 19.3% of the men had a CWT >4.5 cm and 24.1% to 35.4% of the women studied.
  
  
  CONCLUSIONS
  A catheter length of 4.5 cm may not penetrate the chest wall of a substantial amount (9.9%-35.4%) of the population, depending on age and gender. This study demonstrates the need for a variable needle length for relief of a tension pneumothorax in certain population groups to improve effectiveness of needle thoracostomy.
authors.affiliation: Department of Traumatology, University Hospital Maastricht, The Netherlands.
authors.forename: Imme
authors.initials: I
authors.lastname: Zengerink
authors.forename: Peter R
authors.initials: PR
authors.lastname: Brink
authors.forename: Kevin B
authors.initials: KB
authors.lastname: Laupland
authors.forename: Earl L
authors.initials: EL
authors.lastname: Raber
authors.forename: Dave
authors.initials: D
authors.lastname: Zygun
authors.forename: John B
authors.initials: JB
authors.lastname: Kortbeek
mesh_terms: D000328:Adult; D004867:Equipment Design; D005260:Female; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D008875:Middle Aged; D009339:Needles; D011030:Pneumothorax / Q000209:etiology / Q000601:surgery*; D012189:Retrospective Studies; D013907:Thoracostomy / Q000295:instrumentation*; D013909:Thorax / Q000033:anatomy & histology; D014947:Wounds and Injuries / Q000150:complications