A simple and easy in vitro model to test the efficacy of IV lines' needleless connectors against contamination

Intensive Care Medicine Experimental

Table 1 Characteristics of the experiment regarding contamination model and type of instillation fluid

Contamination degree	Instillation fluid	Colonizing microorganisms	MTP (IQR), h	Manipulator hand flora
Hands^a	Saline	S. epidermidis, S. warnerii	76.25 (65.92 to 125.01)	S. epidermidis, S. warnerii, CoNS, SV, P. acnes, Micrococcus sp.
Hands^a	Propofol	Micrococcus sp.	74.91 (51.45 to 99.00)	S. epidermidis, S. warnerii, CoNS, SV, P. acnes, Micrococcus sp.
0.5 MF SA^b	Saline	MSSA (ATCC 29213)	104.92 (45.97 to 239.94)	NA
0.5 MF SA^b	Propofol	MSSA (ATCC 29213)	147.89 (66.04 to 236.58)	NA
0.05 MF SA^c	Saline	MSSA (ATCC 29213)	240.20 (154.82 to 360.00)	NA
0.05 MF SA^c	Propofol	MSSA (ATCC 29213)	66.11 (58.01 to 69.11)	NA
Control^d	Saline	NA	NA	NA
Control^d	Propofol	NA	NA	NA

^aManipulation of the connector without gloves. ^bManipulation of the connector with gloves impregnated with a 0.5 McFarland solution of Staphylococcus aureus ATCC 29213. ^cManipulation of the connector with gloves impregnated with a 0.05 McFarland solution of Staphylococcus aureus ATCC 29213. ^dStandard sterile manipulation with clean gloves and with disinfection of connectors using alcohol. MTP, median time to positivity; IQR, interquartile range; SA, Staphylococcus aureus; MF, McFarland; CoNS, coagulase-negative staphylococci.