Manuel Ignacio Monge GarcÃa, Hospital de Jerez, Spain
28 March 2008
Very interesting idea. But I think that there is something that has been omitted: to draw a venous return curve using the proposed methodology, one must assume that the cardiac function curve doesn´t change when applying increasing inspiratory pressures. This is not true: increasing inspiratory pressure, mechanical ventilation not only change venous return, but also right and left ventricle afterload. So, points obtained from this method should not be an accurate method to estimate mean systemic pressure.
Not accurate method
28 March 2008
Very interesting idea. But I think that there is something that has been omitted: to draw a venous return curve using the proposed methodology, one must assume that the cardiac function curve doesn´t change when applying increasing inspiratory pressures. This is not true: increasing inspiratory pressure, mechanical ventilation not only change venous return, but also right and left ventricle afterload. So, points obtained from this method should not be an accurate method to estimate mean systemic pressure.
Competing interests
None declared