Comparison of 5 Intravenous Connectors on 4 Microorganism CFU Counts

Background: Intravenous connectors are gate keepers of intraluminal fluid pathway.  Institute Healthcare Improvement ranks catheter related bloodstream infections a national priority.  Research needs to compare different products based on infection outcomes.

Objective: Define and compare colony forming units (CFUs) on 4 days, 5 different connectors (MaxPlus® Clear, MicroCLAVE®, Q-Syte™, InVision-Plus® with Neutral Advantage™ Technology, Lifeshield™ TKO™Clave®) in vitro.

Methods: Independent laboratory tested 5 connectors, 20 connectors each, 6 controls, for each of 4 days, same laboratory conditions.  Each connector swabbed, inoculated with minimum viable 10⁵ each organism (Staphylococcus epidermidis = SE, Staphylococcus aureus = SA, Pseudomonas aeruginosa = PA, Escherichia coli = EC). Appropriate equipment, reagents, media, safety used. Repeated measures ANOVA examined differences between connectors over time (alpha=0.05, post hoc test used a Bonferroni adjustment).

Results: Effect across days on each bacterium different for all 5 connectors. Post hoc pair-wise comparisons within connector indicated no statistically significant differences between days except Q-Syte with higher CFUs (p <0.0001) on consecutive days. Number of types bacteria, CFUs ≥1, significantly different between connectors across days. Post hoc pair-wise comparisons within connector between days indicated no differences in number of bacteria types with CFUs≥1 for MaxPlus® Clear, MicroCLAVE®, or InVision-Plus®. For Q-Syte™, days 1 and 2 had significantly lower numbers of bacteria types, CFUs≥1, than day 3 and 4 (p<0.0001).  TKO™/Clave®, day 2 had significantly lower number of bacteria types, CFUs≥1, than day 3 (p=0.0005).  Within each day, Q-Syte™ had significantly higher numbers of bacteria types, CFUs≥1, than other connectors (p<0.0001 for each comparison). For each type of bacteria, Q-Syte™ had significantly higher mean number days, CFUs≥15, than all connectors (all p<0.0001). For SA, MaxPlus® Clear (p=0.0006) and InVision-Plus® (p=0.0003) had significantly lower mean number days, CFUs≥15, than MicroCLAVE®. For SE, InVision-Plus® (p=0.0228) had significantly lower days, CFUs≥15, than MicroCLAVE®. For total number of days with any bacteria CFUs≥15, Q-Syte™ had significantly higher days than all connectors. All bacteria types, using Fisher Exact tests, showed significant difference (p <0.0001) in percentage of connectors, CFUs≥15, across days, with Q-Syte™ and TKO™/Clave® having significantly more CFUs>=15 on 1 or more days.

Conclusions:

Over 4 days Q-Syte™ performed the worst in CFUs on all 4 bacteria types. Over time clinically, the MaxPlus® Clear and MicroCLAVE® fluctuated between high and low CFUs, the Q-Site™ steadily rose, the TKO™/Clave® increased then stayed steady, and InVision-Plus® began low and steadily decreased.  The connector with most bacteria over 4 days was Q-Syte™ and least was InVision-Plus®.