Comparison of manual and machine plasmapheresis techniques

While the benefits of automated plasmapheresis have been described, little data is available to compare it to manual plasmapheresis. We therefore compared standard manual techniques (MP) with three automated devices (AP), Haemonetics^® Models V50 and PCS, and the HemaScience Autopheresis-C^™ (HA). Plasma protein concentrations were 56 ± 4 g/L for MP, 63 ± 2 g/L for the V50, 59 ± 5 g/L for the PCS and 63 ± 5 g/L for the HA. Factor VIII recoveries averaged 105 ± 23 U/dL for the MP, 91 ± 18 U/dL and 125 ± 25 U/dL for the V50 (PPP and PRP modes) 95 ± 27 U/dL for the PCS and 121 ± 22 U/dL for the HA, showing a statistically significant difference (P < 0.05) between manual and automated procedures. Percentage recovery of activity in the cryoprecipitate was similar, giving 337 ± 80 U or 63% for MP, 262 ±70 U or 57% for V50, 252 ± 60 U or 57% for PCS and 367 ± 110 U or 59% for HA.

The plasma from MP and HA contained relatively few cells with 12 ± 5 × 10⁹/L and 6 ± 1 × 10⁹/L platelets; the V50 plasma (PPP mode) contained an average of 103 ± 4 × 10⁹/L platelets whereas the PCS plasma had 51 ± 22 × 10⁹/L. β-Thromboglobulin levels were significantly elevated in the plasma from the V50. Automated procedures took only 30–40 min whereas the manual procedures took a minimum of 2 hr. While different economic factors will affect the choice of methodology, there is considerable benefit to the use of certain automated devices rather than the widely used manual method for the collection of plasma.