Haemodynamic effects of heparin during coronary bypass surgery.
Heparin has been suggested as an activator of the plasma kallikrein-kinin system, with possible formation of bradykinin, a potent vasodilator. Haemodynamic effects and changes in the kallikrein-kinin system were studied after heparin- and saline-injections in ten patients undergoing coronary bypass surgery. A moderate decrease in mean arterial pressure was found in all patients in the observation period, but significantly more at 2 and 3 min after heparin-injection compared with saline-injection. None of the other haemodynamic variables measured were significantly different when comparing heparin- to saline-injection. Heparin-injection resulted in significant changes in the kallikrein-kinin system, with a marked increase in spontaneous kallikrein-like activity as the most prominent feature, while no changes were found after saline-injection. Liberation of bradykinin would be expected to give a decrease in systemic vascular resistance with an increase in cardiac output. The results indicate that the plasma kallikrein-kinin system, though apparently activated after heparin-injection, does not contribute significantly to the decrease in arterial pressure in the patients studied.
Kongsgaard
U E
UE
Department of Anaesthesiology, Rikshospitalet, Oslo, Norway.
Smith-Erichsen
N
N
Hysing
E
E
Tølløfsrud
S
S
Seem
E
E
Geiran
O
O
Bjørnskau
L
L
D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D001026:Coronary Artery Bypass; D004311:Double-Blind Method; D005112:Extracorporeal Circulation; D006439:Hemodynamics / Q000187:drug effects; D006493:Heparin / Q000494:pharmacology*; D006801:Humans; D016234:Kallikrein-Kinin System / Q000187:drug effects*; D007610:Kallikreins / Q000037:antagonists & inhibitors / Q000097:blood; D011288:Prekallikrein / Q000032:analysis; D014655:Vascular Resistance / Q000187:drug effects
D006493:Heparin; D011288:Prekallikrein; D007610:Kallikreins