Sevoflurane preconditioning at 1 MAC only provides limited protection in patients undergoing coronary artery bypass surgery: a randomized bi-centre trial.
BACKGROUND
Volatile agents can mimic ischaemic preconditioning leading to a decrease in myocardial infarct size. The present study investigated if a 15 min sevoflurane administration before cardiopulmonary bypass (CPB) has a cardioprotective effect in patients undergoing coronary surgery.


METHODS
Seventy-two patients were randomized in two centres. The intervention group (S) received 1 MAC sevoflurane administrated via the ventilator for 15 min followed by a 15 min washout before CPB, the control group did not. The primary outcome was the postoperative troponin Ic peak. A biopsy of the atrium was taken during canulation for enzyme dosages. Results are expressed as mean (SD).


RESULTS
Neither troponin Ic nor tissular enzyme measurement exhibited any difference between the groups: peak of troponin Ic was 4.4 (5.6) in S group vs 5.2 (6.6) ng ml(-1) in control group (ns). Intratissular ecto-5'-nucleotidase activity was 7.1 (4.3) vs 8.5 (11.9), protein kinase C activity was 27.1 (15.7) vs 29.2 (28.7), tyrosine kinase activity was 101 (54.1) vs 98.5 (63.3), and P38 MAPKinase activity was 131.1 (76.1) vs 127.1 (86.8) nmol mg protein(-1) min(-1) in S group and control group, respectively (ns). However there were fewer patients with low postoperative cardiac index in S group (11% in S vs 35% in control group, P < 0.05) when considering the per protocol population. In S group, 25% of patients required an inotropic support during the postoperative period, vs 36% of patients in control group (ns).


CONCLUSIONS
This study did not show a significant preconditioning signal after 15 min of sevoflurane administration. The 15 min duration might be too short or the concentration of sevoflurane too low to induce cardioprotection detected by troponin I levels.
Piriou
V
V
EA 1896, Service d'Anesthésie Réanimation, Centre Hospitalier Lyon Sud, Université Claude Bernard Lyon 1, 69495 Pierre Bénite Cedex, France. piriou@univ-lyon1.fr
Mantz
J
J
Goldfarb
G
G
Kitakaze
M
M
Chiari
P
P
Paquin
S
S
Cornu
C
C
Lecharny
J-B
JB
Aussage
P
P
Vicaut
E
E
Pons
A
A
Lehot
J-J
JJ
D000368:Aged; D018685:Anesthetics, Inhalation / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D001026:Coronary Artery Bypass; D004334:Drug Administration Schedule; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D019157:Ischemic Preconditioning, Myocardial / Q000379:methods*; D008738:Methyl Ethers / Q000627:therapeutic use*; D008875:Middle Aged; D015428:Myocardial Reperfusion Injury / Q000517:prevention & control*; D011183:Postoperative Complications / Q000517:prevention & control; D000077149:Sevoflurane; D016896:Treatment Outcome; D019210:Troponin I / Q000097:blood
D018685:Anesthetics, Inhalation; D015415:Biomarkers; D008738:Methyl Ethers; D019210:Troponin I; D000077149:Sevoflurane