Effects of dopamine on intestinal hemodynamics and motility during epidural analgesia in the cat.
The effects of dopamine on intestinal blood flow (IBF) and intestinal contraction rate (ICR), and on mean arterial pressure (MAP) and heart rate (HR) were studied in eight cats before and during epidural analgesia (EDA). Before EDA, dopamine 5 and 10 micrograms.kg-1.min-1 had no effect on IBF, MAP and HR, but the higher infusion rate decreased ICR by 71 +/- 19% (mean +/- 1 s.e.mean) (P less than 0.01). EDA significantly increased IBF when intestinal arterial pressure was maintained at an unchanged level by means of a pump, and transiently increased ICR and intestinal tone, but reduced MAP by 46 +/- 8% (139 +/- 11 to 75 +/- 9 mmHg, P less than 0.01) and HR by 26 +/- 3% (248 +/- 7 to 184 +/- 8 beats.min-1, P less than 0.01). During EDA, dopamine increased IBF further, the response being similar at both infusion rates. 5 micrograms.kg-1.min-1 increased HR by 26 +/- 7 beats.min-1 (P less than 0.01) and MAP by 19 +/- 9 mmHg (ns). The corresponding values at 10 micrograms.kg-1.min-1 were 65 +/- 14 beats.min-1 (P less than 0.01) and 35 +/- 8 mmHg (P less than 0.01), respectively, Vascular autoregulation appeared to be unaffected by dopamine and EDA. The effect of dopamine on ICR was not significantly different to what was seen before EDA. It is concluded that the effects of dopamine on IBF, MAP and HR were markedly different during EDA as compared to before the block and that ICR was reduced by dopamine, while it was transiently increased by EDA.(ABSTRACT TRUNCATED AT 250 WORDS)
Lundberg
J
J
Department of Anesthesiology, University Hospital of Lund, Sweden.
Biber
B
B
Delbro
D
D
Martner
J
J
Werner
O
O
D015360:Analgesia, Epidural; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002415:Cats; D004298:Dopamine / Q000494:pharmacology*; D005260:Female; D005769:Gastrointestinal Motility / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D006706:Homeostasis / Q000187:drug effects; D007082:Ileum / Q000098:blood supply* / Q000187:drug effects / Q000502:physiology; D008297:Male; D012039:Regional Blood Flow / Q000187:drug effects; D014655:Vascular Resistance / Q000187:drug effects
D004298:Dopamine