Perioperative myocardial cell injury: the relationship between troponin T and cortisol.
OBJECTIVE
To investigate whether there is an association between Troponin T (TnT), reflecting myocardial cell injury, and cortisol, reflecting the degree of surgical trauma and associated stress, in light of our recent evaluation of TnT as a marker of perioperative myocardial cell injury.


METHODS
Prospective, cohort study.


METHODS
70 patients (67.4 +/- 8.7 yrs) with definite or at-risk coronary artery disease (CAD) undergoing elective noncardiac surgery (vascular n = 38, abdominal n = 21, orthopedic n = 8) with general (n = 63) or regional (n = 4) anesthesia with postoperative on-demand analgesia.


RESULTS
Morning blood samples for TnT (upper limit of normal: <0.2 ng/mL), CK-MB (reference range </=12 U/L), and cortisol (normal morning range 7-25 mcg/dL) were taken on the day before surgery, on the morning of surgery before induction of anesthesia, and on the first 5 postoperative days. Data were compared by analysis of variance. Three patients were excluded from the study because of incomplete blood samples of TnT or cortisol. Preoperative mean cortisol levels (mcg/dL +/- SD) were within the normal range and equal in TnT positive (n = 13) and negative (n = 54) patients (16.1 +/- 4.5 vs. 15.6 +/- 5.8). On the 1st postoperative day, there was a substantial increase of cortisol in the TnT positive group (35.7 +/- 26.9). Cortisol remained high until the 5th postoperative day (24.7 +/- 9. 4). There was a significant difference in the cortisol concentration in TnT-positive compared to TnT-negative patients (p < 0.001), a significant difference in the perioperative cortisol concentration over time (p < 0.05), and a significant interaction (p < 0.001). But there was no consistent temporal relationship between the increase of TnT and the increase of cortisol.


CONCLUSIONS
The significant relationship between a highly sensitive and specific marker of myocardial cell injury and a marker of stress suggests that cardiac-risk patients undergoing stressful surgical procedures might benefit from close perioperative TnT monitoring with early recognition of myocardial cell injury.
Mahla
E
E
Department of Anaesthesiology and Intensive Care Medicine, Department of Surgery, and Department of Obstetrics and Gynecology, University of Graz, Graz, Austria. cardanaesth@kfunigraz.ac.at
Tiesenhausen
K
K
Rehak
P
P
Fruhwald
S
S
Pürstner
P
P
Metzler
H
H
D000368:Aged; D015331:Cohort Studies; D003327:Coronary Disease / Q000209:etiology; D003402:Creatine Kinase / Q000097:blood; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D007527:Isoenzymes; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology*; D011183:Postoperative Complications / Q000209:etiology; D011446:Prospective Studies; D013312:Stress, Physiological / Q000097:blood; D020107:Troponin T / Q000097:blood*
D007527:Isoenzymes; D020107:Troponin T; D003402:Creatine Kinase; D006854:Hydrocortisone