We present here a simplified method to perform Bidirectional Glenn’s Cavo-Pulmonary Shunt (BDG) in which we use no cardiopulmonary bypass (CPB) nor an intra-operative temporary shunt, sometimes used on the belief that it lessens the developed intra-venous congestion and pressure in the upper torso, intra-operatively. Our approach springs from the idea that acute intra-venous congestion, resulting from the application of vascular cross-clamp on the superior vena cava (SVC) during operation, is being vented through abundant and numerous anatomic venous anastomoses between the SVC system and the inferior vena cava (IVC) system. It also springs from the conception that the brain of patients with low arterial blood O2-saturation tolerates cerebral hypoxia better than the normally functioning brain. Such hypoxia may ensue from the transient low cerebral arterial blood flow, resulting in turn from the temporary intravenous cerebral congestion (and related raised pressure) following SVC clamping.