What studies should be done to validate a new antiseptic before using it for arm preparation of blood donors?

A blood banker in California who works at a hospital donor center reports that her hospital has asked that the donor center switch to ChloraPrep® , a new one-step antiseptic, rather than continue with the current arm prep (described in Method 6.2 of the AABB Technical Manual, 14th ed.) ChloraPrep is 2% chlorhexidine gluconate in 70% isopropyl alcohol. The inquiring blood banker would like to know what e-Network colleagues suggest for validation studies to assure that the ChloraPrep antiseptic system performs effectively before changing arm prep protocols.

The following comments have been received.

ADDENDA Dec. 28, 2003

1. Editor's Note: Although the following question is not directly related to the above-described use of ChloraPrep, it does address the issue of how to validate any deviation from the standard method of skin antisepsis, and therefore is included here.

2. A colleague from a Northern California Community Blood Bank reports that their staff are given the option to clear betadine that has been applied to a donor's skin with 70% isopropol alcohol, in order to improve visualization of the vein, if necessary. However, this strategy is not described in any of the four options approved by the FDA. The inquiring colleague believes they are going above and beyond the guidance. Do others agree? Is anyone else doing this?

ADDENDA Dec. 29, 2003

3. A registered nurse from a blood center in Northern California states that her institution follows FDA recommendations to the letter regarding the phlebotomy site preparation. This center uses either iodine or chlorhexidine procedures. She indicated that her institution has NOT deviated in any aspect from the approved procedures, because they thought it would be easier to justify their approach if they used only a recommended protocol.

ADDENDA Dec. 30, 2003

4. A blood banker in Barcelona submitted this comment: "In our blood bank, we use a two-stage procedure with povidone-iodine 7.5% scrub (Betadine-Scrub) followed by application of 1% PVP-iodine (Orsan). We recently evaluated the persistence of bacteria on blood donors' arms after this preparation of the phlebotomy site. We found bacterial persistence in 35% of donors (ref. 1 below). These results agree with other studies (ref 2 and 3). The best method (ref. 3) revealed zero counts on 70% of arms.

Thus, my opinion is that it may be almost impossible to totally decontaminate human skin. A new antiseptic for phlebotomy site preparation could be validated with our approach as described in reference 1 or with a similar approach (ref 2 and 3). The results with the new antiseptic should be as good or better than those with the current method.

Finally, I'd like to point out that there are some risk factors associated with bacterial persistence on blood donors' arms (ref 1). It seems that a large number of previous donations could be a risk factor because scars are associated with thick, cornified layer of epidermis, rendering unlikely the possibility of achieving complete disinfection."

References:

1. Cid, J et al. Haematologica 2003;888;39-40 (no abstract).
2. Goldman, M et al. Transfusion 1997;37:309-12 (limited to AABB members)
3. McDonald, CP et al. Vox Sang 2001;801:35-41.