Prolonged cardiopulmonary bypass time as predictive factor for bloodstream infection

Area of Science:

• Infectious Diseases
• Cardiovascular Surgery
• Critical Care Medicine

Background:

• Bloodstream infections (BSI) are a significant concern following cardiovascular operations.
• Understanding risk factors and outcomes associated with primary BSI is crucial for patient management.

Purpose of the Study:

• To investigate the correlation between patient characteristics, operative variables, and the risk of BSI after open heart surgery.
• To assess the association between primary BSI and adverse outcomes, including mortality and major cardiovascular events.

Main Methods:

• Retrospective analysis of clinical records from 6500 adult patients undergoing open heart surgery between February 2008 and October 2020.
• Evaluation of the microbiological patterns of primary BSI and its association with adverse events.
• Statistical analysis to identify significant risk factors and outcomes.

Main Results:

• Primary BSI occurred in 1.7% of patients, with gram-negative bacilli (e.g., Serratia marcescens, Enterococcus faecalis, Enterococcus faecium) being the most common pathogens.
• Patients with primary BSI exhibited significantly higher postprocedural mortality, stroke rates, new renal failure, and renal replacement therapy.
• Aortic cross-clamp time >120 min, perfusion time >120 min, and intervention duration >300 min were significantly associated with increased BSI risk.

Conclusions:

• Gram-negative bacilli are the predominant microorganisms causing BSI after cardiopulmonary bypass in cardiac surgery.
• Patients on dialysis prior to surgery are at higher risk for BSI, possibly due to enteric bacterial translocation during prolonged cardiopulmonary bypass.
• Prophylactic antibiotics with broader gram-negative coverage should be considered for high-risk patients, especially those with extended cardiopulmonary bypass and intervention times.