Active Chest Tube Clearance Versus Standard Drainage After Cardiac Surgery

Detailed Description

This multicenter retrospective cohort study evaluates the safety and effectiveness of active chest tube clearance compared to standard passive chest tube drainage in adult patients undergoing cardiac surgery via median sternotomy.

Background:

Postoperative bleeding and retained blood within the chest are common complications following cardiac surgery. Retained blood can lead to Retained Blood Syndrome (RBS), which includes reoperation for bleeding, cardiac tamponade, hemothorax requiring intervention, and retained intrathoracic clot necessitating procedural management. These complications are associated with increased morbidity, longer ICU and hospital stays, and higher healthcare costs.

Study Objectives:

Primary Objective: Compare the incidence of RBS between patients managed with active chest tube clearance versus standard passive drainage.

Secondary Objectives: Assess differences in reoperation for bleeding, cardiac tamponade, hemothorax requiring drainage, postoperative blood transfusion requirements, chest tube occlusion, postoperative atrial fibrillation, ICU length of stay, hospital length of stay, and 30-day mortality.

Study Design:

Type: Observational, retrospective, multicenter cohort study.

Data Collection: Medical records from three tertiary cardiac surgery centers will be reviewed over a 3-year period (January 2022 - December 2024).

Population: Adult patients (≥18 years) who underwent cardiac surgery (CABG, valve surgery, or combined procedures) and had mediastinal chest tubes placed.

Exclusions: Redo sternotomy, acute aortic dissection surgery, heart transplantation, mechanical circulatory support implantation, incomplete medical records, or intraoperative death.

Groups:

Group A: Active chest tube clearance strategy

Group B: Standard passive chest tube drainage

Definitions:

Retained Blood Syndrome (RBS): Any of reoperation for bleeding, cardiac tamponade requiring intervention, hemothorax requiring drainage, or retained clot requiring procedural management.

Chest Tube Occlusion: Documented loss of drain patency requiring manipulation, flushing, or replacement.

Data Collection Variables:

Demographics: Age, sex, BMI

Preoperative Variables: Diabetes, hypertension, chronic kidney disease, anticoagulant/antiplatelet therapy, LVEF, urgency status

Operative Variables: Procedure type, cardiopulmonary bypass time, aortic cross-clamp time, number/size of chest tubes

Postoperative Variables: Chest tube output, reoperation, transfusions, atrial fibrillation, ICU and hospital stay, 30-day mortality

Sample Size:

Approximately 200-300 patients (100-150 per group), based on case availability, providing sufficient power to detect clinically meaningful differences in RBS incidence.

Statistical Analysis:

Continuous variables: mean ± SD or median (IQR)

Categorical variables: frequencies and percentages

Between-group comparisons: Student's t-test, Mann-Whitney U test, chi-square or Fisher's exact test

Multivariable logistic regression to identify independent predictors of RBS

Propensity score analysis if significant baseline differences exist

Center and surgeon effects will be explored and adjusted for

Significance: p < 0.05

Ethical Considerations:

Retrospective, observational study

No interventions beyond standard care

Data anonymized and stored securely

Waiver of informed consent requested due to minimal risk

Potential Benefits:

While no direct benefit to participants exists, the study may improve postoperative chest drainage strategies, reduce retained blood complications, and optimize perioperative outcomes in future cardiac surgery patients.

Timeline:

Month 0: Ethical approval

Months 1-3: Data collection

Month 4: Statistical analysis

Months 5-6: Manuscript preparation

Funding: None Conflicts of Interest: None

Inclusion criteria

• Adult patients (≥18 years) undergoing cardiac surgery via median sternotomy, including CABG, valve surgery, or combined procedures.

Placement of mediastinal chest tubes postoperatively

Exclusion criteria

• Redo sternotomy

Surgery for acute aortic dissection

Heart transplantation

Mechanical circulatory support implantation

Incomplete or missing essential medical records

Intraoperative death