# Utility of the Charlson Comorbidity Index in the Preoperative Evaluation of Patients Undergoing Cardiac Surgery

## TL;DR

The study shows that the Charlson Comorbidity Index helps predict postoperative complications in cardiac surgery patients, improving preoperative planning.

## Contribution

The study demonstrates the CCI's effectiveness in predicting specific complications in cardiac surgery patients.

## Key findings

- Severe comorbidity is linked to higher rates of delirium, stroke, transfusion, and renal replacement therapy.
- Logistic regression identified delirium, pneumonia, acute kidney injury, and renal replacement therapy as independent predictors of severe comorbidity.
- Higher CCI scores correlate with increased Sequential Organ Failure Assessment scores post-surgery.

## Abstract

The Charlson Comorbidity Index (CCI) is used for assessing comorbidities and
estimating risk of adverse outcomes in surgical patients. In cardiac
surgery, the burden of comorbidities can significantly influence incidence
of postoperative complications and mortality. This study evaluates the
utility of CCI in predicting perioperative complications in patients
undergoing cardiac surgery.

Observational cross-sectional study with retrospective data including 483
adult patients who underwent cardiac surgery with cardiopulmonary bypass at
the Instituto Nacional de Cardiología Ignacio Chávez from June
2022 to December 2023. Patients were grouped by preoperative CCI: mild (0 -
1), moderate (2), and severe (≥ 3). Statistical analyses (chi-square,
Mann-Whitney U, logistic regression) assessed the association between CCI
and postoperative complications, adjusting for age and sex.

Patients with severe comorbidity had higher rates of postoperative
complications, including delirium (27.3% vs. 9.4%, P = 0.00), stroke (P =
0.03), transfusion (69.7% vs. 47.2%, P = 0.04), and renal replacement
therapy (18.2% vs. 5.3%, P = 0.02). Median Sequential Organ Failure
Assessment scores at 24 hours were significantly higher (P = 0.00). Logistic
regression adjusted for age, sex, and coronary artery bypass grafting
identified delirium (odds ratio [OR]: 3.13), nosocomial pneumonia (OR:
3.10), acute kidney injury (OR: 2.28), and renal replacement therapy (OR:
4.10) as independent predictors of severe comorbidity.

The CCI is a valuable tool for predicting postoperative complications in
patients undergoing cardiac surgery. Early identification of comorbidities
is essential for perioperative planning and optimizing clinical outcomes.
Integrating the CCI into routine clinical practice is recommended to enhance
patient management.