title: Hemodynamic effects of thoracic epidural analgesia in ovine hyperdynamic endotoxemia.
abstract: OBJECTIVE
  Thoracic epidural analgesia (TEA) is increasingly used for perioperative analgesia. If patients with TEA develop sepsis or systemic inflammatory response subsequent to extended surgery the question arises if it would be safe to continue TEA with its beneficial effects of improving gastrointestinal perfusion and augmenting tissue oxygenation. A major concern in this regard is hemodynamic instability that might ensue from TEA-induced vasodilation. The objective of the present study was to assess the effects of TEA on systemic and pulmonary hemodynamics in a sepsis model of hyperdynamic endotoxemia.
  
  
  METHODS
  After a baseline measurement in healthy sheep (n = 14), Salmonella thyphosa endotoxin was continuously infused at a rate of 10 ngxkg(-1)xmin(-1) over 16 hours. The surviving animals (n = 12) were then randomly assigned to 1 of 2 study groups. In the treatment group (n = 6), continuous TEA was initiated with 0.1 mLxkg(-1) bupivacaine 0.125% and maintained with 0.1 mLxkg(-1)xh(-1). In the control group (n = 6) the same amount of isotonic sodium saline solution was injected at the same rate through the epidural catheter.
  
  
  RESULTS
  In both experimental groups cardiac index increased and systemic vascular resistance decreased concurrently (each P < .05). Functional epidural blockade in the TEA group was confirmed by sustained suppression of the cutaneous (or panniculus) reflex. During the observational period of 6 hours neither systemic nor pulmonary circulatory variables were impaired by TEA.
  
  
  CONCLUSIONS
  From a hemodynamic point of view, TEA presents as a safe treatment option in sepsis or systemic inflammatory response syndrome.
authors.affiliation: Department of Intensive Care Medicine, University Hospital of Bern, Bern, Switzerland. fritz.daudel@insel.ch
authors.forename: Fritz
authors.initials: F
authors.lastname: Daudel
authors.forename: Christian
authors.initials: C
authors.lastname: Ertmer
authors.forename: Henning D
authors.initials: HD
authors.lastname: Stubbe
authors.forename: Matthias
authors.initials: M
authors.lastname: Lange
authors.forename: Rafael
authors.initials: R
authors.lastname: Pulina
authors.forename: Hans-Georg
authors.initials: HG
authors.lastname: Bone
authors.forename: Andreas W
authors.initials: AW
authors.lastname: Sielenkämper
authors.forename: Hugo
authors.initials: H
authors.lastname: Van Aken
authors.forename: Martin
authors.initials: M
authors.lastname: Westphal
mesh_terms: D015360:Analgesia, Epidural / Q000379:methods*; D000818:Animals; D002302:Cardiac Output / Q000502:physiology; D000075202:Contraindications; D004195:Disease Models, Animal; D019446:Endotoxemia / Q000503:physiopathology*; D011897:Random Allocation; D012485:Salmonella typhi; D012756:Sheep; D013904:Thoracic Vertebrae / Q000294:innervation; D014655:Vascular Resistance / Q000502:physiology; D014664:Vasodilation / Q000502:physiology*