Neuroendocrine and cardiovascular responses to high-dose corticosteroid therapy in canine endotoxin shock.
The neuroendocrine and cardiovascular responses to endotoxin administration and the effects of subsequent high-dose corticosteroid therapy have been investigated in dogs. Shock was induced in anaesthetised animals by a large bolus of E. coli endotoxin (5 mg/kg) followed by a continuous infusion (2 mg/kg per hour). One hour after induction of shock, the circulating volume was expanded using a colloidal gelatin solution. Fifteen minutes later, one group of five animals received a bolus of methylprednisolone sodium succinate 30 mg/kg, while a control group of five animals was given an equivalent volume of isotonic saline. The administration of endotoxin produced reductions in mean arterial pressure, cardiac index and left ventricular dp/dtmax, together with increases in systemic and pulmonary vascular resistances. These haemodynamic changes were associated with increases in arterial plasma levels of adrenaline, noradrenaline, cortisol, immunoreactive beta-endorphin and immunoreactive metenkephalin. Cardiovascular improvement followed volume replacement and was associated with reductions in circulating catecholamines. No significant haemodynamic or neuroendocrine changes were demonstrated in the 2 h following steroid therapy.
Watson
J D
JD
Anaesthetic Laboratory, St. Bartholomew's Hospital, London, UK.
Varley
J G
JG
Tomlin
S J
SJ
Medbak
S
S
Perry
L
L
Bouloux
P M
PM
Rees
L H
LH
Besser
G M
GM
Hinds
C J
CJ
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D004195:Disease Models, Animal; D004285:Dogs; D004731:Endotoxins; D004744:Enkephalin, Methionine / Q000097:blood; D004837:Epinephrine / Q000097:blood; D006321:Heart / Q000187:drug effects / Q000503:physiopathology*; D006854:Hydrocortisone / Q000097:blood; D008775:Methylprednisolone / Q000627:therapeutic use*; D009638:Norepinephrine / Q000097:blood; D011652:Pulmonary Circulation / Q000187:drug effects; D012016:Reference Values; D012772:Shock, Septic / Q000188:drug therapy* / Q000503:physiopathology; D014655:Vascular Resistance / Q000187:drug effects
D004731:Endotoxins; D004744:Enkephalin, Methionine; D006854:Hydrocortisone; D009638:Norepinephrine; D008775:Methylprednisolone; D004837:Epinephrine