Impact of an Evidence-Based Antibiotic Protocol on Common Gram-Negative Bacteria's Antibiotic Resistance in a Cardiac Surgical Intensive Care Unit

Infections Acquired During Venoarterial Extracorporeal Membrane Oxygenation Postcardiac Surgery in Children: A Retrospective Observational Study

Introduction Extracorporeal membrane oxygenation (ECMO) is increasingly being used in refractory cardiac and pulmonary dysfunction as a rescue modality. The common indications for establishing venoarterial ECMO (VA-ECMO) support in children postcardiac surgery are failure to wean from cardiopulmonary bypass (CPB), postcardiotomy cardiogenic shock (PCCS), refractory pulmonary arterial hypertension, and as a bridge to recovery or transplant. The survival rate of children on VA-ECMO support is 45%. The most frequently encountered complications during VA-ECMO are bleeding, thrombosis, acute kidney injury, and infections. Among those, infections acquired during VA-ECMO lead to high morbidity and mortality. Hence, this study aimed to determine infection rates, causal microorganisms, and mortality risk factors in children developing an infection during VA-ECMO therapy.

Methods This retrospective observational study was conducted on 106 children under 14 years of age who underwent elective or emergent cardiac surgery (between 2016 and 2020) and required VA-ECMO support. Medical records were reviewed to collect the targeted variables and analyzed.

Results Out of 106 children, 49 (46.23%) acquired infections representing a prevalence of 46.23% and an infection rate of 186.4 episodes per 1,000 ECMO days. Prevalence and acquired infection rate/1,000 ECMO days were higher in the nonsurvivor group than in the survivor group (26.42 vs.19.81%) and (215.07 vs. 157.49), respectively. The bloodstream infection (BSI) and catheter-associated urinary tract infection (CAUTI) episodes were 53.04 and 68.19 per 1,000 ECMO days, and the ventilator-associated pneumonia (VAP) rate was 44.50 per 1,000 ventilator days. The mean preoperative admission duration, aortic cross-clamping duration, CPB duration (minutes), and vasoactive-inotropic score were higher in the nonsurviving children (p < 0.001). Similarly, prolonged mean ECMO duration was also found in the nonsurvivor group compared with the survivor group (p = 0.03).

Conclusion In our study, the prevalence of acquired infection during VA-ECMO was 46.23%. The incidence of BSI, CAUTI, and VAP per 1,000 ECMO days was higher in the nonsurvivor group than in survivors. Acinetobacter baumannii was the most common cultured gram-negative organism in VAP and BSI, with 67.65% Acinetobacter spp. resistant to carbapenems. CAUTI was predominately due to Candida species during VA-ECMO.