Temporal synthesis and release of endothelin within the systemic and myocardial circulation during and after cardiopulmonary bypass: relation to postoperative recovery.
OBJECTIVE
To determine endothelin levels in arterial, pulmonary, and myocardial vascular compartments in patients undergoing coronary artery bypass graft surgery and to examine the influence of endothelin on postoperative recovery.


METHODS
Prospective, clinical study.


METHODS
University hospital.


METHODS
Fifty patients undergoing elective coronary artery bypass graft surgery.


METHODS
Endothelin plasma content (fmol/mL) was measured in 50 patients undergoing coronary revascularization from various vascular compartments before surgery and at specific intervals up to 24 hours postoperatively.


RESULTS
Myocardial endothelin gradient (coronary sinus - aorta) was calculated before cardiopulmonary bypass (CPB), at release of the aortic cross-clamp, immediately after CPB, and 0.5 hour after CPB. The requirement for inotropic therapy and duration of patient stay in the intensive care unit were determined. Systemic and pulmonary endothelin levels were increased by >80% immediately after CPB when compared with preoperative values and increased again by approximately 60% during the first 24 hours postoperatively (p < 0.05). The myocardial endothelin gradient was reversed after CPB, indicating myocardial production of endothelin (pre-CPB, -0.72+/-0.39 fmol/mL v 0.5 hour post-CPB, 0.60+/-0.49 fmol/mL; p < 0.05). Longer intensive care unit times (>28 hours) were associated with higher systemic endothelin levels when compared with shorter times (<18 hours) (16.30+/-1.33 fmol/mL v 9.81+/-1.67 fmol/mL; p < 0.05). Patients with higher endothelin levels 6 hours postoperatively had greater inotropic requirements during the intensive care unit period.


CONCLUSIONS
Endothelin levels after CPB remained persistently increased for at least 24 hours after surgery and were associated with increased myocardial production of endothelin. These results suggest that the increased endothelin observed in the early postoperative period may contribute to a complex recovery from coronary artery bypass graft surgery.
Dorman
B H
BH
Department of Anesthesia and Perioperative Medicine, Medical University of South Carolina, Charleston 29425, USA.
Bond
B R
BR
Clair
M J
MJ
Walker
C A
CA
Pinosky
M L
ML
Reeves
S T
ST
Kratz
J M
JM
Zellner
J L
JL
Crumbley
A J
AJ
Multani
M M
MM
Spinale
F G
FG
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002315:Cardiopulmonary Bypass; D003326:Coronary Circulation; D016232:Endothelins / Q000096:biosynthesis* / Q000097:blood; D006801:Humans; D007362:Intensive Care Units; D008875:Middle Aged
D016232:Endothelins