1. Plasma albumin concentration was decreased in thirty-five of eighty-six mobilized para- or tetra-plegic patients studied months or years after injury to the spinal cord causing a medullary cross-sectional syndrome. The colloid osmotic pressure was low in thirty-one of eighty-one patients in whom it was measured. Plasma volume was normal in thirty and slightly elevated in three of thirty-three patients in whom it was determined. None had oedema at the time of the investigation.
2. Albumin metabolism was studied in ten patients by means of 131I-labelled albumin. Six of these had a decreased plasma albumin concentration. This was probably caused by an increased fractional catabolic rate, although a statistically significant causal relationship could not be demonstrated.
3. in spite of the low plasma albumin concentration normal compensatory mechanisms such as an increase in rate of albumin synthesis and shift of albumin from the extravascular to the intravascular compartment were not found. On the contrary, for unexplained reasons, the average rate of synthesis and the ratio intravascular/total albumin mass were both decreased.