Microcirculatory changes in children undergoing cardiac surgery: a prospective observational study

Area of Science:

• Pediatric Cardiology
• Vascular Biology
• Critical Care Medicine

Background:

• The impact of cardiac surgery on the microcirculation of children remains largely unknown.
• Congenital heart disease necessitates surgical correction, often involving complex procedures.
• Understanding microcirculatory changes is crucial for optimizing patient outcomes.

Purpose of the Study:

• To assess microcirculatory alterations in pediatric patients undergoing surgical correction of congenital heart disease.
• To investigate the time-dependent changes in microvascular parameters post-cardiac surgery.
• To explore potential correlations between microcirculatory variables and clinical factors.

Main Methods:

• Utilized Sidestream Dark Field (SDF) videomicroscopy in 24 children under five years old.
• Measured total vascular density (TVD), microvascular flow index (MFI), proportion of perfused small vessels (PPV), and perfused vessel density (PVD) at multiple time points.
• Data collected post-anesthesia, post-surgery, upon ICU admission, and at 6 and 12 hours post-ICU admission.

Main Results:

• Overall microcirculatory variables showed no significant changes over time.
• No significant correlation was observed between hemodynamic parameters and microcirculatory variables.
• Significant interactions between time and cyanosis status were found for PPV, TVD, and PVD in a subanalysis (P=0.03 for all).
• Storage time of transfused red blood cells (RBCs) showed weak inverse correlations with MFI at T3 (r=-0.63, P=0.01) and T4 (r=-0.53, P=0.03).

Conclusions:

• Microcirculatory trends differ between cyanotic and acyanotic children following cardiac surgery.
• The storage duration of transfused RBCs appears to negatively influence microcirculation.
• Further research with larger cohorts is needed to confirm these findings and their clinical implications.