Document Detail


Effects of dopexamine and positive end-expiratory pressure on intestinal blood flow and oxygenation: the perfusion pressure perspective.
MedLine Citation:
PMID:  12907561     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
OBJECTIVE: To evaluate the net effects of the concomitant use of positive end-expiratory pressure (PEEP) and dopexamine on intestinal tissue perfusion and oxygenation during predefined artificial reductions in intestinal perfusion pressure (IPP). DESIGN: Prospective, self-controlled, experimental study. SETTING: University hospital research laboratory. SUBJECTS: Seven female pigs. MEASUREMENTS: In barbiturate-anesthetized pigs, we measured mesenteric blood flow (QMES) [by transit-time ultrasonic flowmetry], jejunal mucosal perfusion (by laser Doppler flowmetry), and tissue PO(2) (by microoximetry). Based on blood sampling, we calculated the intestinal net lactate production and oxygenation. INTERVENTIONS: These measurements and calculations were performed at three predefined and controlled IPP levels, which were obtained by an adjustable clamp around the superior mesenteric artery. At each IPP level, measurements were performed prior to and during PEEP (10 cm H(2)O), both with and without simultaneous dopexamine infusions (at 0.5 and 1.0 microg/kg/min). RESULTS: Within the IPP range of 77 to 33 mm Hg, intestinal perfusion and oxygenation were maintained irrespective of whether PEEP and/or dopexamine were applied or not. At IPP < 33 mm Hg, QMES and intestinal oxygenation deteriorated, resulting in regional net lactate production. At this IPP range, tissue oxygen perfusion was entirely pressure-dependent, and even small reductions in IPP led to prominent increases in intestinal net lactate production. Dopexamine did not modify this pattern. CONCLUSIONS: We describe maintained intestinal tissue oxygen perfusion within a wide perfusion pressure range. Within this perfusion pressure range, PEEP did not induce any adverse regional circulatory effects. Below the perfusion pressure range for effective autoregulation, intestinal tissue oxygen perfusion deteriorated, and regional ischemia occurred. In this situation, dopexamine was unable to counteract IPP-dependent decreases in intestinal tissue oxygen perfusion. The regional ischemic threshold can be defined either as an IPP of < 33 mm Hg or as an intestinal tissue PO(2) of < 45 mm Hg.
Authors:
Stefan Lehtipalo; Björn Biber; Rolf Fröjse; Conny Arnerlöv; Göran Johansson; Ola Winsö
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Chest     Volume:  124     ISSN:  0012-3692     ISO Abbreviation:  Chest     Publication Date:  2003 Aug 
Date Detail:
Created Date:  2003-08-08     Completed Date:  2003-09-04     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0231335     Medline TA:  Chest     Country:  United States    
Other Details:
Languages:  eng     Pagination:  688-98     Citation Subset:  AIM; IM    
Affiliation:
Anesthesiology and Intensive Care Unit, Department of Surgical and Perioperative Sciences, Umeå University Hospital, Umeå, Sweden. lehtipalo@vll.se
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MeSH Terms
Descriptor/Qualifier:
Adrenergic beta-Agonists / pharmacology*
Animals
Dopamine / analogs & derivatives*,  pharmacology*
Female
Intestines / blood supply*,  drug effects,  metabolism
Lactates / metabolism*
Oxygen / metabolism*
Positive-Pressure Respiration*
Pressure
Swine
Chemical
Reg. No./Substance:
0/Adrenergic beta-Agonists; 0/Lactates; 7782-44-7/Oxygen; 86197-47-9/dopexamine
Comments/Corrections
Comment In:
Chest. 2003 Aug;124(2):427-8   [PMID:  12907524 ]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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