Patients under antidepressants undergoing cardiac surgery have a high risk for adverse events

Objective: The percentage of patients suffering from pathological mood disorders under specific medication is steadily increasing in society, and therefore also in cardiac surgical patients. Thus, this study aimed to evaluate a possible impact of preoperative antidepressant medication (AM) on outcome.

Methods: A propensity score matched case-control study was conducted by including all patients who underwent myocardial revascularization and/or surgical valve operation in our institution from December 2008 till February 2011 by chart review and quality assurance database (BQS) analysis. A statistical comparison was applied.

Results: Out of incorporated 1949 pts, n = 184 pts (9%) were isolated under AM (A). The matched control group [n = 184 pts; C] did not differ in age 70 ± 10 y, logistic Euroscore 8 ± 10%, ejection fraction 58 ± 15%, type or urgency of operation, and aortic cross clamping time 59 ± 22 min [respectively p = ns]. However, patients under AM were significantly longer on the ICU [A: 5 ± 7 d, vs. C: 3 ± 3 d, p = 0.003], had longer mechanical ventilation times [A: 29 ± 88h, vs. C: 17 ± 32h, p = 0.258] and significantly more episodes of respiratory insufficiencies leading to more reintubations and tracheotomies [A: 31 episodes (17%), vs. C: 17 episodes (9%); p = 0.002]. Regression analysis revealed preoperative AM as a significant risk factor for respiratory insufficiency [Odds ratio: 1.99; CI: 1.0 – 3.74; p = 0.04]. Chest tube drainage [A: 690 ± 750 ml; vs. C: 691 ± 1240 ml; p = 0.53] and the total amount of red blood cell transfusion was similar [A: 1272 ± 1146 ml, vs. C: 1241 ± 847 ml, p = 0.37]. Renal replacement therapy was more frequent in A [n = 6 pts (3%)] than in C [n = 3 pts (1%) (p = 0.31)]. Patients under AM developed slightly more often atrial fibrillation [n = 19 pts (10%)] compared to C [n = 11 pts (6%), p = 0.12]. Sternal dehiscence requiring sternal refixation was significantly more frequent in A [n = 12 pts (6%), vs. C n = 2 pts (1%), p = 0.06]. Surprisingly, 30 d mortality was similar in both groups [A: n = 6 pts (3%), vs. C: n = 4 pts (2%) (p = 0.5)].

Conclusion: Patients under preoperative antidepressant medication have an underestimated risk for adverse events after cardiac surgery. The underlying likely multifactorial mechanisms remain unclear. The increasing patient population under antidepressant medication needs to be identified, and particular care including optimal pre- and postoperative psychiatric assistance is recommended.