Relationship Between the Pulmonary-to-systemic-blood-flow Ratio and the Cross-sectional Area of the Right Internal Jugular Vein in Pediatric Patients With Congenital Heart Disease.

Objectives: To investigate the relationship between the pulmonary-to-systemic-blood-flow ratio (Qp/Qs) and the cross-sectional area (CSA) and diameter of the right internal jugular vein (RIJV) in pediatric patients with congenital heart disease using multivariate analysis.

Design: Retrospective study.

Setting: Operating room of a tertiary children's hospital.

Participants: Pediatric patients aged <10 years with congenital heart disease who underwent cardiovascular surgery under general anesthesia.

Interventions: None.

Measurements and main results: Multiple linear regression analyses were performed, with the CSA of the RIJV as the primary outcome and the anteroposterior and transverse diameters of the RIJV as secondary outcomes. These were designated as dependent variables, while Qp/Qs served as the independent variable. The analyses were adjusted for the following factors: weight, sex, postbidirectional Glenn operation, preoperative diuretic use, number of previous median sternotomies, single ventricle, trisomy 21, superior vena cava pressure, systolic blood pressure, heart rate, hemoglobin concentration, partial pressure of carbon dioxide, pH of arterial blood, and cardiac index. The adjusted regression coefficient estimates for Qp/Qs were as follows: 0.88 (95% confidence interval: 0.84-0.94, p < 0.001), 0.94 (95% confidence interval: 0.92-0.97, p < 0.001), and 0.94 (95% confidence interval: 0.91-0.97, p < 0.001) in the CSA, anteroposterior diameter, and transverse diameter of the RIJV, respectively.

Conclusions: A higher Qp/Qs was associated with a smaller CSA, as well as reduced anteroposterior and transverse diameters of the RIJV. Specifically, for each unit increase in Qp/Qs, the CSA of the RIJV decreased by approximately 12%.