Background: In 2012, Octogenarians accounted for 13.8% of the patients undergoing cardiac surgery
in Germany. This rose to 18.6% in 2019 and as of 2021 more than one-in-five patients
undergoing cardiac surgery was 80 years old or older. Delirium after cardiac surgery
remains a common occurrence that results in significant short- and long-term morbidity
and mortality. We aim to analyze the outcomes and identify risk factors of postoperative
delirium in the elderly.
Methods: Data were collected from our institutional database. Between January 2012 and December
2019, 684 patients were operated who were ≥ 80 years old. 100 patients (14.6%) suffered
from postoperative Delirium. Delirium was diagnosed in a standard manner using the
evaluated using the “Confusion Assessment Method” for the ICU (CAM-ICU). Data was
analyzed using IBM SPSS version 25 (Statistical Package for the Social Sciences, IBM
Corporation, New York, USA). Data are presented as medians (interquartile range) or
absolute values (percentages). Multivariate analysis incorporated binary logistic
regression using a forward stepwise model, where significance for entry was set at
p < 0.05, and significance for exit was p < 0.10.
Results: The median age was 82 (80–24) in the Delirium group and 81 (80–83) years in theNon-delir
group (p = 0.328). No differences with respect to gender, BMI, urgency of surgery and comorbidities
such as arterial hypertension, diabetes mellitus type II, peripheral arterial disease
and chronic kidney disease. No differences with regard to postoperative morbidities
such as low cardiac output, adverse cerebrovascular events and renal replacement therapy.
A higher number of patients suffering from delirium were transferred to other hospitals
(37.0% vs. 25.2%, p = 0.020). Survival to discharge was comparable (97.0 vs. 94.2% p = 0.340). In the multivariable analysis COPD (OR 0.523; [95% CI 0.312–0.879], p = 0.014), duration of ventilation (OR 0.997; [95% CI 0.995–0.999], p = 0.002) and ICU stay (OR 1.090; [95% CI 1.043–1.140], p < 0.001) were independently associated with the development of postoperative delirium.
Conclusion: As the cardiac surgical patients keep getting older, postoperative delirium plays
an important role in the postoperative course. Patients suffering from delirium had
longer cross clamp and ventilation times as well as longer ICU and in-hospital stays.
Following cardiac surgery, measures should be taken to prevent delirium.
