The problem with the pre is just not loading the nephron with blood. And so you're not getting filtration. But the problem here is the neephron is dying or has been significantly injured. So it's not handling the fluid that's filtered very well. The sodium, the urine, the sodium in the urine could be relatively normal or actually high. Because it's not being reabsorbed. Now this is essentially a problem with the normal flow of urine downstream to post-respiratory failure.