Limiting and detecting bacterial contamination of apheresis platelets: inlet-line diversion and increased culture volume improve component safety.
BACKGROUND
Septic transfusion reactions to apheresis platelets (PLTs) continue to occur despite preventive measures. This study evaluated the effect of two operational changes designed to reduce bacterial risk: 1) introducing inlet-line sample diversion on two-arm procedures and 2) increasing the sample volume cultured from 4 to 8 mL from all donations.


METHODS
Aerobic culture results and septic transfusion reactions reported between December 1, 2006, and July 31, 2008 (Period 2), were compared to March 1, 2004, to May 31, 2006 (Period 1).


RESULTS
During Period 2, a total of 781,936 apheresis PLT collections were cultured, of which 130 donations (1:6015) were confirmed positive and 9 (1:86,882) had negative culture results but were associated with 11 septic reactions. Confirmed-positive cultures from two-arm procedures decreased (27.2 to 14.7 per 105 collections; odds ratio [OR], 0.54; 95% confidence interval [CI], 0.41-0.70) in Period 2, owing to a lower rate of skin flora contamination. Detection of contamination of one-arm collections significantly increased by 54% in Period 2 (13.7 vs. 21.1 per 105 collections; OR, 1.54; 95% CI, 1.05-2.27). Fewer septic transfusion reactions occurred in Period 2, but the difference did not reach significance (1.7 vs. 1.2 per 105 donations; OR, 0.68; 95% CI, 0.30-1.53).


CONCLUSIONS
Inlet-line diversion decreased bacterial contamination during two-arm collections by more than 46%. Concurrently, doubling the sample volume was associated with a 54% relative increase in culture sensitivity. These interventions act cooperatively to decrease bacterial risk.
Biomedical Services, National Headquarters, American Red Cross, 2025 E Street N.W.,Washington, DC 20006, USA. EderA@usa.redcross.org
Anne F
AF
Eder
Jean M
JM
Kennedy
Beth A
BA
Dy
Edward P
EP
Notari
Robert
R
Skeate
Gary
G
Bachowski
David C
DC
Mair
Jonathan S
JS
Webb
Stephen J
SJ
Wagner
Roger Y
RY
Dodd
Richard J
RJ
Benjamin
D001419:Bacteria / Q000254:growth & development* / Q000302:isolation & purification*; D001431:Bacteriological Techniques / Q000379:methods; D001792:Blood Platelets / Q000382:microbiology*; D018929:Cell Culture Techniques; D004866:Equipment Contamination; D005260:Female; D006801:Humans; D008297:Male; D017713:Platelet Transfusion; D010983:Plateletpheresis; D012189:Retrospective Studies