title: The effects of remifentanil and thoracic epidural on oxygenation and pulmonary shunt fraction during one-lung ventilation.
abstract: OBJECTIVE
  To compare the effects of remifentanil and thoracic epidural analgesia on the hemodynamic changes and pulmonary shunt fraction during one-lung ventilation (OLV) for thoracotomy.
  
  
  METHODS
  Prospective, single crossover design.
  
  
  METHODS
  Tertiary care hospital.
  
  
  METHODS
  Thirty-four patients undergoing OLV for thoracic surgery.
  
  
  METHODS
  During general anesthesia with 2-lung ventilation, one-lung ventilation with remifentanil infusion, and one-lung ventilation with thoracic epidural anesthesia (TEA), hemodynamic parameters and arterial and mixed venous blood gases were taken from the radial and pulmonary artery catheters. During these 3 study periods, cardiac index (CI) was measured using thermodilution technique while shunt fraction (Qs/Qt), alveolar arterial oxygen gradient (A-a O(2)), and systemic (SVRI) and pulmonary vascular resistances indices (PVRI) were calculated. A p value <0.05 was taken to be statistically significant.
  
  
  RESULTS
  When OLV was instituted, there was a significant decrease in mean arterial blood pressure. Arterial oxygenation decreased, whereas CI and Qs/Qt increased during OLV, but there was no significant difference between remifentanil infusion and thoracic epidural analgesia.
  
  
  CONCLUSIONS
  Both remifentanil infusion and TEA are suitable for analgesia during thoracic surgery when OLV is used. There was no significant difference in PaO(2) and Qs/Qt during each administration.
authors.affiliation: Department of Anaesthesia and Surgical Intensive Care Unit, Singapore General Hospital, Singapore. markchow@bigfoot.com
authors.forename: Mark Yew-Hoong
authors.initials: MY
authors.lastname: Chow
authors.forename: Meng-Huat
authors.initials: MH
authors.lastname: Goh
authors.forename: Sek Koon
authors.initials: SK
authors.lastname: Boey
authors.forename: Agasthian
authors.initials: A
authors.lastname: Thirugnanam
authors.forename: Pierre Christian
authors.initials: PC
authors.lastname: Ip-Yam
mesh_terms: D015360:Analgesia, Epidural / Q000706:statistics & numerical data*; D000701:Analgesics, Opioid / Q000494:pharmacology*; D000768:Anesthesia, General / Q000706:statistics & numerical data; D001784:Blood Gas Analysis / Q000706:statistics & numerical data; D018592:Cross-Over Studies; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood*; D010880:Piperidines / Q000494:pharmacology*; D011446:Prospective Studies; D011652:Pulmonary Circulation / Q000502:physiology*; D000077208:Remifentanil; D012121:Respiration, Artificial / Q000706:statistics & numerical data*; D013908:Thoracotomy
chemical_list: D000701:Analgesics, Opioid; D010880:Piperidines; D000077208:Remifentanil; D010100:Oxygen