Heterogeneity of the vasoconstrictor effect of vasopressin in septic shock.
OBJECTIVE
To determine whether pressor doses of vasopressin impair organ blood flow in endotoxic shock.


METHODS
Graded doses of vasopressin or phenylephrine, starting at the clinically recommended doses for pressure support in septic shock, were intravenously infused during endotoxic shock.


METHODS
University hospital surgical research laboratory.


METHODS
Twelve random-bred female Yorkshire pigs.


METHODS
We measured mean arterial pressure, cardiac output, heart rate, pulmonary artery occlusion pressure, and carotid, mesenteric, renal, and iliac blood flows.


RESULTS
Low doses of vasopressin (typically used in the clinical management of septic shock) raised arterial pressure by increasing systemic vascular resistance without a significant preferential effect in the circulations measured. However, moderately greater doses of vasopressin had a very heterogeneous vasoconstrictor action; although there was no significant vasoconstriction in the carotid and iliac circulations, mesenteric and renal blood flows decreased markedly. Furthermore, at pressor doses vasopressin improved cerebral perfusion.


CONCLUSIONS
The vasoconstrictor action of exogenous low-dose vasopressin in endotoxic shock does not impair blood flow to any of the vascular beds examined. However, moderately higher doses of vasopressin may induce ischemia in the mesenteric and renal circulations. The data indicate that the safe dose range for exogenous vasopressin in septic shock is narrow and support the current practice of fixed low-dose administration, generally 0.04 units/min and in no case exceeding 0.1 units/min.
Malay
Mary-Beth
MB
Allegheny University of the Health Sciences, Allegheny General Hospital, Division of General Surgery, Pittsburgh, PA, USA.
Ashton
Jennifer L
JL
Dahl
Katherine
K
Savage
Edward B
EB
Burchell
Sherryl A
SA
Ashton
Robert C
RC
Sciacca
Robert R
RR
Oliver
Juan A
JA
Landry
Donald W
DW
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D002339:Carotid Arteries / Q000187:drug effects; D002560:Cerebrovascular Circulation / Q000187:drug effects; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D007083:Iliac Artery / Q000187:drug effects; D008638:Mesenteric Arteries / Q000187:drug effects; D010656:Phenylephrine / Q000494:pharmacology; D011651:Pulmonary Artery / Q000187:drug effects; D012077:Renal Artery / Q000187:drug effects; D012772:Shock, Septic / Q000503:physiopathology*; D013552:Swine; D014661:Vasoconstriction / Q000187:drug effects*; D014662:Vasoconstrictor Agents / Q000008:administration & dosage / Q000494:pharmacology*; D014667:Vasopressins / Q000008:administration & dosage / Q000494:pharmacology*
D014662:Vasoconstrictor Agents; D014667:Vasopressins; D010656:Phenylephrine