Juniper Publishers-Open Access Journal of Anesthesia & Intensive Care Medicine
Increased Pulmonary Venous Resistance in the Critically Ill Patients by Charles Her in Juniper Publishers in Journal of Anesthesia & Intensive Care Medicine
In patients with sepsis, the presence of radiographic evidence of pulmonary edema may not necessarily indicate the fluid overload. The increased pulmonary venous resistance by endotoxemia can develop pulmonary edema in the absence of left ventricular volume overload. Development of pulmonary edema in this situation can contribute to less aggressive efforts of intravascular volume expansion, thus leading to hypovolemia. A previous study examined risk factors and clinical outcomes associated with Transfusion-Associated Circulatory Overload (TACO), using the NHSN TACO Definition 2016 to identify cases of TACO, without defining the intravascular volume status. The problem is that most of criteria in NHSN TACO Definition 2016 could be explained by the increased pulmonary venous resistance rather than by TACO. In many cases there were probably no TACO. Interestingly, more patients in TACO group in that study had been on β-adrenergic blocker preoperatively, which increases pulmonary venous resistance by blocking β2-adrenergic vasodilating effect. Inhalation of Salmeterol may prevent acute pulmonary edema by decreasing pulmonary venous resistance. The low pulmonary venous resistance would keep the lung water low. Likewise, possibility that the radiographic appearance of pulmonary edema by the increased pulmonary venous resistance, despite the absence of the left ventricular overload, could have contributed to less aggressive efforts of intravascular volume expansion, thus leading to hypovolemia in many cases of Sepsis-3 Definition, cannot be excluded. In conclusion, without considering the possible presence of the increased pulmonary venous resistance and/or monitoring intravascular volume status, the validation of any definition regarding circulatory overload or sepsis is questionable.
