Natriuretic Peptides as a Prognostic Marker for Delirium in Cardiac Surgery—A Pilot Study

Abstract

Background and Objectives: Delirium is a common and major complication subsequent to cardiac surgery. Despite scientific efforts, there are no parameters which reliably predict postoperative delirium. In delirium pathology, natriuretic peptides (NPs) interfere with the blood–brain barrier and thus promote delirium. Therefore, we aimed to assess whether NPs may predict postoperative delirium and long-term outcomes. Materials and Methods: To evaluate the predictive value of NPs for delirium we retrospectively analyzed data from a prospective, randomized study for serum levels of atrial natriuretic peptide (ANP) and the precursor of C-type natriuretic peptide (NT-proCNP) in patients undergoing coronary artery bypass grafting (CABG) with or without cardiopulmonary bypass (off-pump coronary bypass grafting; OPCAB). Delirium was assessed by a validated chart-based method. Long-term outcomes were assessed 10 years after surgery by a telephone interview. Results: The overall incidence of delirium in the total cohort was 48% regardless of the surgical approach (CABG vs. OPCAB). Serum ANP levels > 64.6 pg/mL predicted delirium with a sensitivity (95% confidence interval) of 100% (75.3–100) and specificity of 42.9% (17.7–71.1). Serum NT-proCNP levels >1.7 pg/mL predicted delirium with a sensitivity (95% confidence interval) of 92.3% (64.0–99.8) and specificity of 42.9% (17.7–71.1). Both NPs could not predict postoperative survival or long-term cognitive decline. Conclusions: We found a positive correlation between delirium and preoperative plasma levels of ANP and NT-proCNP. A well-powered and prospective study might identify NPs as biomarkers indicating the risk of delirium and postoperative cognitive decline in patients at risk for postoperative delirium.

Lower surgical Apgar score is predictive on delirium in patients following off-pump coronary artery bypass grafting

“…Therefore, the ideal sedative treatment is beneficial to reduce stress response in patients after cardiac surgery, reduce man-machine confrontation, reduce oxygen consumption, stabilize hemodynamics and reduce delirium or restlessness, to ensure the completion of the invasive operation 11-14 . Some prophylactic strategies for the prevention of delirium have been proposed, but not routinely implemented because of the lack of convincing evidence 15 . Surgical Apgar Score (SAS) system was initially validated in patients undergoing general and vascular surgery and was subsequently expanded to a majority of surgical subspecialties [16][17][18][19][20][21] .…”