Multidose vial contamination in anesthesia

The intent of this research was to address the following question: Will an alteration in the drug aspiration technique cause a significant difference in the incidence of multidose vial contamination? The control group consisted of multidose vials collected at the end of each day from staff anesthetists. The use of these vials reflected the practice technique of a single needle and syringe for each vial. The vial, as well as needle and syringe, were used on all cases managed for the day. The experimental group consisted of multidose vials collected at the end of each day from the four investigators. The vials and syringes were utilized in the same manner as the control group with the exception that a new needle was used each time a vial was reentered. Upon completion of the collection period, guaiac testing, using Hemoccult slides and developer, was performed on a 0.1 cc sample from each vial. A multidose vial was considered positive for blood contamination if traces of blue appeared on the Hemoccult slide in a 15-minute period. A chi-square statistic was applied to the cumulative data. The control group consisted of 492 multidose vials. Of the 492 multidose vials tested, 11 were guaiac positive, 2.24%. The experimental group consisted of 369 multidose vials. Of the 369 multidose vials, one tested guaiac positive, 0.27%. A chi-square test on the cumulative data demonstrated a significant (p less than .05) difference between the two groups. The research demonstrated that occult blood may be contained within the used multidose vials suggesting that contaminated drug may then be injected into another patient.