Baseline sleep as a predictor of delirium after surgical aortic valve replacement: A feasibility study

Objective: The goal is to assess the feasibility of conducting unattended (type II) sleep studies before surgical aortic valve replacement (SAVR) to examine the relationship between baseline sleep measures and postoperative delirium. Methods: This single-site study recruited 18 of 20 study referrals with aortic stenosis undergoing first lifetime SAVR. Subjects completed a home-based type II sleep study. Delirium was assessed postoperative days 1–5. Exact logistic regression was used to determine whether sleep efficiency or apnea/hypopnea index predicts delirium. Results: Of 18 study participants, 15 successfully completed a home sleep study (mean age: 71.7 +/− 8.1 years old; 10 male subjects). Five subjects (33.3%) developed delirium. Preliminary analyses found that greater sleep efficiency was associated with a large reduction in delirium odds but was not statistically significant (OR = 0.31, 95% CI: 0.06, 1.03, p = 0.057). The point estimate of the relationship between apnea/hypopnea index and delirium was not similarly sizeable (OR 1.10, 95% CI: 0.35, 3.37, p = 0.85). Conclusions: Our findings suggest that home type II sleep studies before SAVR are feasible, and they support adequately powered studies investigating type II home sleep studies as a predictor of postoperative delirium and other important postsurgical outcomes.