Tuesday, February 1, 2011

Sterile gloves for drawing blood cultures?

Photo: RightHealth.com
A new study in the Annals of Internal Medicine evaluated whether blood culture contamination could be reduced if the phlebotomist wore sterile gloves. The study was performed in a 1600-bed Korean teaching hospital where all blood cultures are drawn by interns. The design was a cluster randomized crossover trial. Over 10,500 blood cultures were evaluated, and a contaminant was defined when only 1 of 2 of more blood culture sets were positive for skin flora (which in this study included enterococci).

The authors found a reduction in contaminated cultures from 1.1% to 0.6% (OR 0.57, p 0.009) with sterile gloves.

It's worth pointing out that cultures drawn through lines were excluded, as were cultures obtained in the Emergency Department (an area of high contamination rates in some hospitals), pediatrics wards and surgical wards. In addition, povidone-iodine was used as the skin disinfectant.

When I was a resident, all blood cultures were drawn by housestaff and I proudly recall that I never had a contaminated blood culture (and I did wear sterile gloves). But we had a vested interest in avoiding contaminants, as it would mean drawing more cultures and potentially extending the patient's hospital stay, all of which meant more work for us.


  1. People don't always use sterile gloves, etc. for drawing blood cultures? I always used sterile gloves and povidone iodine (we actually had a set routine, approved by the head of pathology, so it minimized the risk of contamination). I paid my way through grad school working as a pediatric phlebotomist and I never had a contaminated blood culture.

  2. The results of this study make sense to me. Like many now- old doctors who were trained in the stone age when house officers drew all blood cultures and routine blood specimens, it always seemed odd that the normal technique for drawing blood cultures required a skin prep FOLLOWED by manual probing for a palpable vein using one's [contaminated] [non sterile] gloved finger before the blood sample was drawn. Slopping betadine on the finger used for probing is probably futile since nobody has the time or patience to let it dry. I am sure that many American doctors won't accept the validity of these data unless or until it is repeated in an American facility. Perhaps we should buy and stock sterile gloves in boxes containing packages containing just one sterile glove. Of course left handers, like me would need their special supply.

  3. Glove use is a PhD skill. It would be interesting to randomize the gloves into clean/sterile, but TELL the techs they are all sterile gloves. My guess is that HOW they use the gloves and what they touch before the blood draw changes, depending on if they think the gloves are clean or the gloves are sterile. (at least enough for the odds to go from even odds to 0.57) I love to observe and watch the gloves go on at the door and then touch the siderails, the linens, the call light, the light switch before the blood draw itself. Human behavior is so interesting.