Sixteen studies (2,358 patients, range 36 to 153 patients) and 224,449 total catheter days were included in the review. The total number of episodes recorded in particular arms within trials ranged from zero to 78. Seven studies were assessed as adequate regarding allocation concealment. Two studies were double-blinded. Eight reported adequate description of drop-outs (where reported, study drop-out levels ranged from 2% to 6%). One study reported use of intention-to-treat analysis.
Haemodialysis patients: (nine studies)
Compared with standard heparin lock solution, antibiotic-based lock solutions had a statistically significantly lower CRBSI (IDD -1.96, 95% CI -2.63 to -1.30, I2=41.3%). This difference was also present in a subgroup of five studies in which heparin was compared with heparin plus antibiotics (IDD -2.08, 95% CI -2.64 to -1.53, I2=0%) and a subgroup of three studies in which heparin was compared with antibiotics plus citrate (IDD -2.88, 95% CI -4.34 to -1.41, I2=0%).
Oncology patients: (six studies)
Overall results were not pooled. Within a subgroup of five studies in which antibiotic flush was used in children with malignancies there was a borderline statistically significant effect that favoured treatment over control (IDD -0.52, 95% CI -1.07 to -0.02, I2=41.8%). One study investigated the effectiveness of antibiotic locks in adults with malignancies and found no statistically significant difference compared with heparin lock solution.
High-risk neonates: (one study)
A statistically significant effect favoured antibiotic locks over heparin locks (IDD -13.15, 95% CI -24.73 to -1.56).
A funnel plot of haemodialysis patient studies only was strongly asymmetrical (publication bias could not be ruled out). A funnel plot of oncology patient studies was broadly symmetrical (no publication bias detected).