Soft tissue infections related to peripheral intravenous catheters in hospitalised patients: a case-control study

Peripheral intravenous (i.v.) catheter-related soft tissue infections begin with local skin and soft tissue inflammation, which can progress to cellulitis or even tissue necrosis requiring aggressive surgical treatment. We conducted a matched case-control study to investigate risk factors for peripheral i.v. catheter-related soft tissue infections in hospitalised patients. We retrospectively identified 46 cases that occurred during 2006-2008 in two teaching hospitals. Each case was randomly matched with four control subjects from the same ward and on the same day that the soft tissue infections arose. Risk factors were analysed using conditional logistic regression. Multiple regression analysis identified the following independent risk factors: >24h of continuous i.v. fluid infusion (odds ratio: 5.2, P=0.001), insertion site in lower extremity (8.5, P=0.003), use of an infusion pump (4.6, P=0.023), and hospitalisation due to a neurological or neurosurgical condition (3.6, P=0.018). The population-attributable fractions (the percentage of cases in the study population that could be prevented if the exposure were removed) were 40%, 19%, 24% and 25%, respectively. Minimising unnecessarily prolonged i.v. fluid infusion and avoidance of insertion in the lower extremity may significantly reduce the incidence of peripheral i.v. catheter-related soft tissue infection in the study hospitals.