title: Heliox therapy for pneumothorax: new indication for an old remedy.
abstract: OBJECTIVE
  To evaluate a new method of treating pneumothorax: having the subject breathe a helium/oxygen mixture (heliox).
  
  
  METHODS
  We conducted a prospective, randomized, controlled study of nine white rabbits weighing 2.5 to 3.5 kg. Experimental pneumothorax was induced in all rabbits with the injection of 20 mL of air into the pleural space. The rabbits then breathed heliox, oxygen, or room air for 2 hours. Chest radiography was performed 5 minutes after induction of pneumothorax, then at 1 and 2 hours. We determined pneumothorax size on the chest radiograph by measuring the interpleural distance and expressing it as a percentage of the hemithorax.
  
  
  RESULTS
  At 2 hours the pneumothoraces in the heliox group had diminished from 17.50% +/- .50% to .17% +/- .29%; in the oxygen-breathing group they had diminished from 17.83% +/- 2.25% to .50% +/- .50%; and in the air-breathing group they had diminished from 18.50% +/- 3.12% to 17.33% +/- .25%. The difference between the air-breathing and the oxygen-breathing or heliox-breathing animals was highly significant; no significant difference was found between the oxygen and heliox groups (P<.0001).
  
  
  CONCLUSIONS
  Heliox, a safe and convenient therapy, is as effective as oxygen in reducing the volume of an experimental pneumothorax in rabbits.
authors.affiliation: Pediatric Intensive Care Unit, Assaf Harofeh Medical Center, Zerifin, Israel. jbarr@post.tau.ac.il
authors.forename: J
authors.initials: J
authors.lastname: Barr
authors.forename: G
authors.initials: G
authors.lastname: Lushkov
authors.forename: R
authors.initials: R
authors.lastname: Starinsky
authors.forename: B
authors.initials: B
authors.lastname: Klin
authors.forename: M
authors.initials: M
authors.lastname: Berkovitch
authors.forename: G
authors.initials: G
authors.lastname: Eshel
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D006371:Helium / Q000627:therapeutic use*; D010100:Oxygen / Q000627:therapeutic use*; D011030:Pneumothorax / Q000000981:diagnostic imaging / Q000628:therapy*; D011817:Rabbits; D011859:Radiography; D011897:Random Allocation; D012138:Respiratory Therapy / Q000379:methods*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D006371:Helium; D010100:Oxygen