Neutrophil and platelet dynamics at organ level after cardiopulmonary bypass: An in vivo study in neonatal pigs

The aim was to investigate if organ dysfunction is a consequence of cell accumulation in the tissue and whether this accumulation is caused by the cardiopulmonary bypass (CPB) procedure. Twenty-six piglets were used in the sham group (sternotomy, n=12) or in the CPB group (sternotomy, CPB, n=14). Isotope-labeled autologous 99mTc-neutrophils (PMNs) and 111In-platelets were infused and dynamically followed at organ level with a gamma camera before, during, and 4 h after termination of CPB. The CPB group showed a 49% increase in 99m Tc-PMNs in the kidneys in the postoperative period compared to a decrease of 2% in the sham group. A less marked decrease was observed in the lungs and peripheral blood between the two groups. The increased radioactivity at organ level post-CPB could be due to changes in flow, extraction in the organ or accumulation of cells, especially in the kidneys and lungs, and might contribute to temporary organ dysfunction postoperatively.