Multiple Sterile Withdrawals from Iohexol Bottles Does Not Increase Contamination Risk

There is a global shortage of iohexol contrast media, commonly used in epidural injections, as a result of lockdown and decreased production due to COVID-19. Iohexol bottles are designated for single use, which, depending on the vials available, often leads to wasting up to 95% of this limited resource. However, avoiding multiple withdrawals may be unnecessary if withdrawing multiple times using sterile technique does not increase the risk for contamination.

The purpose of our study is to determine whether multiple withdrawals from iohexol injection bottles using a sterile technique poses a greater risk of introducing contaminants than a single withdrawal. Furthermore, we wish to determine the extent to which bacteria can survive and grow in the contrast media.

Experimental.

Outpatient fluoroscopic suite and laboratory.

Twenty-one 100 mL 300 mg(iodine)/mL iohexol injection bottles, after one clinical use, were tested after the first and last withdrawals (withdrawal one and withdrawal 9 or 10) for bacterial and fungal specimens using culture media and 3M™ Petrifilms™. To determine the ability of methicillin-susceptible Staphylococcus aureus (MSSA) to survive or grow in the media, MSSA was added to different concentrations (0, 25, 50, 75, and 100%) of iohexol contrast media.

There was no growth observed in cultures or on Petrifilms among the first and last draws of any of the samples. When bacteria were grown in different dilutions of the media, there was a significant, approximately one log decrease in counts from 0% contrast media to 100% contrast media (8.4 x 108 vs 5.6 x 107, P < 0.01).

Our study is limited in the number of samples tested and would benefit from additional investigation before consideration of clinical application.

Our results suggest that single-use 300 iohexol bottles may be reusable and that the contrast media is mildly antimicrobial, but not enough to retard contamination. In setting of shortages, contrast media bottles can safely be reused. This is valuable for conserving resources and limiting unnecessary health care-associated costs.