Effect of Therapeutic Plasma Exchange on Plasma Constituents in Neurointensive Care Unit Patients: A Retrospective Study

Abstract

Purpose Plasma exchange is one of the recommended therapeutic procedures for autoimmune neurological conditions and involves removal of plasma over multiple sessions for exclusion of autoantibodies responsible for the disease process. This study aimed to evaluate the changes in the concentration of plasma constituents with five cycles of alternate day therapeutic plasma exchange (TPE), identify contributing factors for hypoproteinemia, and examine its impact on clinical outcomes. Methods This was a single-center, retrospective cohort study involving patients with autoimmune neurological diseases who underwent at least five cycles of TPE in the neurointensive care unit (NICU). Data regarding plasma protein concentrations, serum electrolytes, fluid input/output before and after every TPE cycle and clinical outcomes in terms of duration of ventilation, and NICU and hospital stay were collected from the medical records over a 1-year period. Results The levels of plasma proteins (total protein, albumin and globulin) (p < 0.001), sodium (p < 0.001), calcium (p < 0.001), and hemoglobin (p = 0.002) declined significantly after TPE. Difference in plasma protein levels before and after TPE did not correlate with durations of mechanical ventilation and hospital and NICU stay. Difference in total protein and globulin correlated negatively with fluid balance and positively with daily protein intake (p < 0.05 for both). Conclusion A significant decrease in plasma proteins and other plasma constituents is seen with TPE. Changes in plasma proteins are related to hemodilution and protein intake. Decrease in plasma proteins did not affect duration of hospital or NICU stay and duration of mechanical ventilation.