Hi, edema may also be due to local causes (eg phlebitis, retroperitoneal obstruction), tensor bandages to the hips will promote vascular refilling.If you use tensors, tell the patient to keep them on until they go to bed, otherwise, fluid will redistribute in the upright posture, and symptoms may develop. If the RV function and pulmonary artery pressure are normal, the CVP may reflect the ECF volume, however, it may be misleading in the presence of pulmonary hypertension or impaired RV function or RV filling (eg tamponade or diastolic dysfunction).when right sided pressures do not reflect what the LV is seeing. If you are asking about the use of 3% saline to expand the ECF volume at the expense of the ICF, that may be useful early in the dialysis, but you must take care to send the patient home with their usual post dialysis [Na], or there will be increased interdialytic weight gain, compounding the problem (unless your target DW is too low.You can calculate the change in Blood Volume from beginning to end of the treatment by measuring the Hct at the onset and end of dialysis, using the formula % Change in blood volume = (initial Hct/ final Hct) - 1. Patients usually tolerate a fall in BV of 10% quite well, whereas > 15% often causes symptoms. Let us know the outcome. Cheers. Marc