J Thorac Cardiovasc Surg 2008;135:466-467
© 2008 The American Association for Thoracic Surgery
Thoracic epidural anesthesia and atrial fibrillation after coronary bypass grafting
John G.T. Augoustides, MD, FASE
Department of Anesthesiology and Critical Care, Hospital of the University of Pennsylvania, Philadelphia, Pa
To the Editor:
I read with great interest the recent article by Dr Bakhtiary and colleagues1
detailing the protective effect of high thoracic epidural anesthesia against atrial fibrillation after off-pump coronary bypass grafting. The following clinical questions arise as a result of this fascinating study:
- 1. Why was the placement of the thoracic epidural catheters the day before the operation?
- 2. Were there any thoracic epidural placements complicated by significant puncture-site bleeding? What was the protocol for managing this uncommon but important event? Was another epidural space selected?
- 3. How was the epidural catheter tested to ensure effective bilateral thoracic anesthesia?
- 4. What was the management of postoperative β-blockade? Was β-blocker withdrawal a possible confounder in this study?
- 5. Is there any explanation for the observation that women were more likely to experience nausea and vomiting in the intervention group?
- 6. What was the power calculation for this study based on the existing literature? What is the probability of a type I error, a type II error, or both?
- 7. Is aprotinin exposure a consideration, given its trend to protect against atrial fibrillation after coronary surgery?2
- 8. Is hyperglycemia a possible confounder, given its association with higher rates of atrial fibrillation after cardiac surgery?3 Was there a standardized approach to perioperative glucose management? Insulin therapy has been shown to be protective against postoperative atrial fibrillation.4
- 9. Was perioperative magnesium therapy standardized, given its link with the incidence of atrial fibrillation after cardiac surgery?5
I congratulate the authors again on a most excellent study. I look forward to their feedback about these considerations.
Footnotes
Supported by the Department of Anesthesiology and Critical Care, Hospital of the University of Pennsylvania, Philadelphia, Pa.
References
- Bakhtiary F, Therapidis P, Dzemali O, Ak K, Ackermann H, Meininger D, et al. Impact of high thoracic epidural analgesia on incidence of perioperative atrial fibrillation in off-pump coronary bypass grafting: a prospective randomized study. J Thorac Cardiovasc Surg 2007;134:460-464.[Abstract/Free Full Text]
- Sedrakyan A, Treasure T, Elefteriades JA. Effect of aprotinin on clinical outcomes after coronary artery bypass graft surgery: a systematic review and meta-analysis of randomized clinical trials. J Thorac Cardiovasc Surg 2004;128:442-448.[Abstract/Free Full Text]
- Gandhi GY, Nuttall GA, Abel, MD, Mullany CJ, Schaff HV, Williams BA, et al. Intraoperative hyperglycemia and perioperative outcomes in cardiac surgery patients. Mayo Clin Proc 2005;80:862-866.[Medline]
- Bothe W, Olschewski M, Beyersdorf F, Doenst T. Glucose-insulin-potassium in cardiac surgery: a meta-analysis. Ann Thorac Surg 2004;78:1650-1657.[Abstract/Free Full Text]
- Miller S, Chrystal E, Garfinkle M, Lau C, Lashevsky I, Connolly SJ. Effects of magnesium on atrial fibrillation after cardiac surgery; a meta-analysis. Heart 2005;91:618-623.[Abstract/Free Full Text]
