Change in pulmonary blood volume changes pulmonary artery systolic storage

Increased Pulmonary Venous Resistance in the Critically Ill Patients

“…In support of these findings, an increase in pulmonary artery systolic storage has been shown to be associated with the more even distribution of ventilation-to-perfusion ratios in patients with Acute Respiratory Distress Syndrome (ARDS) [7,8]. As such, this study has clearly demonstrated that the development of acute pulmonary edema does not necessarily indicate left ventricular volume overload during intravascular volume expansion, particularly when pulmonary venous resistance is increased.…”

“…Also, it has been shown that in patients with sepsis [5] or with morbid obesity [6], an increase in pulmonary venous resistance contributes to pulmonary artery diastolic-occlusion pressure gradient. Furthermore, a clinical study [7] has shown that when pulmonary blood volume is increased by hydration in patients with sepsis or morbid obesity, only the group of patients with a high pulmonary venous resistance develop the more uneven distribution of ventilation-to-perfusion ratios of the lung (Figure 2), as a result of an increase in non-pulsatile pulmonary capillary blood volume, which can lead to pulmonary edema. A positive correlation between PASS and PvR/TPVR ratio in patients with a PAD-PCWP gradient higher than 6 mmHg (closed circles).…”

“…PASS denote pulmonary artery systolic storage (fraction of the portion of right ventricular stroke volume stored in the pulmonary artery during systole and discharged to the pulmonary capillaries during diastole), PvR/TPVR the ratio of pulmonary venous resistance/total pulmonary vascular resistance, and PAD-PCWP gradient pulmonary artery diastolic-occlusion pressure gradient. Data from the previous study on morbid obesity [7] and data from other study on acute respiratory distress syndrome [8] were pooled. Reproduced with permission from J Surg Res (2013) 185: 310-318.…”