An experimental and clinical evaluation of a novel central venous catheter with integrated oximetry for pediatric patients undergoing cardiac surgery.

BACKGROUND

Central venous oxygen saturation (ScvO2) accurately reflects cardiocirculatory function, but is not always feasible in pediatric patients. Using an experimental and clinical approach, we determined the accuracy of a novel pediatric central venous catheter with integrated fiberoptic oximetry, correlated ScvO2 to periprocedural vital variables, and tested its feasibility in pediatric cardiac surgery patients.

METHODS

In five anesthetized pigs, hemodynamics (cardiac index [CI], heart rate; mean arterial blood [MAP]; mean pulmonary artery [MPAP], central venous pressure [CVP]), fiberoptic ScvO2 (ScvO2-cath), and blood gas oximetry (ScvO2-blood) were measured during stable baseline conditions, preload reduction (caval occlusion), and dopamine infusion (5 mcg x kg(-1) x min(-1)). In 16 pediatric patients undergoing cardiac surgery (median age 8.4 mo; weight 8.0 kg), central venous oximetry catheters were placed percutaneously, and ScvO2-cath and hemodynamics recorded at several time-points during and until 24 h after surgery. Oximetry and hemodynamic data were compared by correlation (Pr) and the Bland-Altman analysis.

RESULTS

There were no catheter-related complications. ScvO2-cath and ScvO2-blood measurements correlated significantly (P < 0.001) in both the experimental (Pr = 0.96) and clinical protocol (Pr = 0.94). A similar bias and precision over all time-points was detected in both protocols (Exp-bias: +0.03% +/- 4.11%; Clinical-bias: -0.03% +/- 4.41%). ScvO2-cath correlated (P < 0.001) with CI (Pr = 0.87), MAP (Pr = 0.59), MPAP (Pr = 0.44), and CVP (Pr = 0.38) and estimated CI better than MAP (Pr = 0.61), MPAP (Pr = 0.38), CVP (Pr = 0.35), or heart rate (Pr = 0.25).

CONCLUSION

Integrated central venous oximetry catheters provide accurate continuous ScvO2 monitoring in pediatric patients undergoing cardiac surgery. ScvO2 fiberoptic oximetry correlates better with changes in CI as compared to routine hemodynamic variables.