Is the risk of Delirium reduced in Minimal Invasive Cardiac Surgery

Background: The number of cardiac operations is steadily increasing in industrialized countries, being Delirium one of the most frequent postoperative complications. Aortic Valve Replacement by mini-invasive surgery has reported to offer innumerable benefits over Complete Sternotomy, such as better esthetic, less surgical trauma, pain, blood and postoperative complications, a functional recovery and a shorter hospital stay. Objectives: To determine the frequency of Delirium and to identify its risk factors in patients undergoing mini-sternotomy (MS) versus full sternotomy (FS) isolated aortic valve replacement (AVR). Methods: An interdisciplinary, descriptive and retrospective study of 113 adults patients who underwent an Isolated Aortic Valve Replacement (AVR) with mini-sternotomy (MS) and full sternotomy (FS) was conducted. Variables related to delirium were characterized as being present before, during or after cardiac surgery. Results: Delirium occurred in 26 patients (23%). In the MS group, 12 patients (25%) had Delirium while 36 (75%) had no Delirium. In the FS group, 14 (21.5%) patients had Delirium whereas 51 did not have it (78.5%) and P: 0.66. Regarding to valve type among Delirium patients, 5 had a mechanical one while 21 patients with a biological valve. P: 0.02. Late extubation had 7 (6.2%) patients in the Delirium group versus 1 (9%) in the non-Delirium group. P: 0.001. Postoperative Hb analysis revealed an average of 9.2mg/dL and 9.8mg/dl for Delirium and non - Delirum patients respectively. P: 0.05. Renal disease was showed in 8 (7.1%) patients in the Delirium group versus 4 in the No delirium group (3.5%) with a P value of 0.001. No mortality event has been registered in any of the groups. Conclusion: MS has shown numerous advantages over conventional surgery before this study, nevertheless the risk of Delirium has not been previously assessed in this context. The risk factors and an increasing frequency of Delirium should be taking into account due to its high morbidity rate and significant cost of the health system.