Ultrashort acting remifentanil is not superior to long-acting sufentanil in preserving cognitive function-a randomized study.

STUDY OBJECTIVE: Postoperative cognitive dysfunction (POCD) is a well-known complication after cardiac surgery and may cause permanent disabilities with severe consequences for quality of life. The objectives of this study were, first, to estimate the frequency of POCD after on-pump cardiac surgery in patients randomized to remifentanil- or sufentanil-based anesthesia and, second, to evaluate the association between POCD and quality of recovery and perioperative hemodynamics, respectively.

DESIGN: Randomized study.

SETTING: Postoperative cardiac recovery unit, University Hospital.

PATIENTS: Sixty patients with ischemic heart disease scheduled for elective coronary artery bypass grafting ± aortic valve replacement.

INTERVENTIONS AND HANDLING: Randomized to either remifentanil or sufentanil anesthesia as basis opioid. Postoperative pain management consisted of morphine in both groups.

MEASUREMENTS: Cognitive functioning evaluated preoperatively and on the 1st, 4th, and 30th postoperative day using the cognitive test from the Palo Alto Veterans Affairs Hospital. Perioperative invasive hemodynamics and the quality of recovery was evaluated by means of invasive measurements and an intensive care unit discharge score.

MAIN RESULTS: No difference between opioids in POCD at any time. A negative correlation was found between preoperative cognitive function and POCD on the first postoperative day (r=-0.47; P=.0002). The fraction of patients with POCD on the first postoperative day was statistically greater in patients with more than 15minutes of Svo2 <60 (P=.037; χ(2) test). Among patients with postoperative ventilation time exceeding 300minutes, more patients had POCD on postoperative day 4 (P=.002).

CONCLUSIONS: We could not demonstrate differences in POCD between remifentanil and sufentanil based anaesthesia, but in general, the fraction of patients with POCD seemed smaller than previously reported. We found an association between POCD and both perioperative low Svo2 and postoperative ventilation time, underlining the importance of perioperative stable hemodynamics and possible fast-track protocols with short ventilation times to attenuate POCD.