Figure 3.

A graph depicting the relationship of inspired oxygen, PVR, left pulmonary blood flow, arterial oxygenation and preductal SpO₂ is illustrated in an ovine model of meconium aspiration model with PPHN. [36] The pulmonary vascular resistance (PVR—brown cross), pulmonary blood flow (Qp—purple open circles), FiO₂ (blue circles) and PaO₂ (red squares) at different preductal saturation (SpO₂) ranges are shown. Preductal SpO₂ in high 80 s resulted in high PVR and low Qp. Preductal SpO₂ in the low−90 s was associated with increased PaO₂, increased Qp, low FiO₂ and high PVR (due to high pulmonary arterial pressure–not shown). Preductal SpO₂ in the mid−90 s was associated with FiO₂ in the 0.5 range with lowest PVR, highest Qp in this model. Increasing FiO₂ to 1.0 increased PaO₂ and SpO₂ but did not result in further increase in Qp or decrease in PVR. For detailed statistical analysis, please refer to Rawat et al. [36]. Copyright Satyan Lakshminrusimha.