Cardiac troponin I versus creatine kinase-MB in the detection of postoperative cardiac events after coronary artery bypass grafting surgery.

AIM: Several studies suggest that postoperarive concentrations of cardiac troponin-I (cTnI) may increase in patients undergoing aorto-coronary bypass grafting (CABG). The degree and pattern of release appears to be associated with perioperative myocardial damage. METHODS: This was a prospective observational study with serial sampling conducted at the Departments of Cardiothoracic Surgery and Anesthesiology, University Hospital of Ioannina, Ioannina, Greece. The levels of cTnI and creatine kinase-MB (CK-MB) preoperatively, upon admission to the intensive care unit and at 12, 24, 36 and 48 hours after surgery, as well as daily from postoperative days 3-7 were determined in 41 consecutive patients (33 males and 8 females, aged 64.8+/-6.1 years) who underwent CABG with cardiopulmonary bypass. The Authors compared the patterns and variation of cTnI and creatine kinase (CK)-MB after CABG in patients with or without postoperative cardiac events (PCEs). RESULTS: Eleven patients experienced a PCE (postoperative ventricular and supraventricular arrhythmia, need for intra-aortic balloon pump (IABP) for >12 hours, or postoperative myocardial infarction, [MI]). In patients without PCE the elevation of cTnI peaked at 24 hours after surgery, while in patients with PCE maximal values of cTnI occurred after 36 hours. CTnI levels correlated with CK-MB after the procedure. Receiver-operating characteristic (ROC) curve analysis indicated that cTnI is superior to CK-MB with regard to PCE diagnosis following CABG (area under the ROC curve, 0.73, 95% CI (0.53-0.93) versus 0.54, 95% CI, (0.25-0.83). CONCLUSION: CTnI seems to be more valuable compared to CK-MB in the detection of PCEs in patients undergoing coronary surgery.

Knotting of an epidural catheter: a rare complication.

Knotting of an epidural catheter leading to entrapment is a rare complication of epidural catheterization. A lumbar epidural catheter inserted in a 28-year-old woman for caesarean section anesthesia and postoperative analgesia proved difficult to remove. After multiple attempts and placing the patient in the same position as when the catheter was initially inserted, the entrapped catheter was dislodged intact, revealing a double knot near its distal tip. Leaving catheters of less than 4 cm in length in the epidural space may help to avoid this complication. It is important the patient be informed of the techniques involved in the extraction of the resistant catheter because patient's cooperation is important for the nonsurgical removal of an entrapped epidural catheter.