Reduction of drain-associated cerebrospinal fluid infections in neurosurgical inpatients: a prospective study

Abstract

External cerebrospinal fluid (CSF) diversion via a drain is associated with a variable risk of associated infections which cause significant morbidity. To establish whether simple interventions can reduce the incidence of such infections at a single centre. A retrospective review of all patients undergoing an external CSF diversion procedure was carried out to determine the historical rate of infection. Following an institutional protocol which included standards on drain insertion, care, sampling and antibiotic prescribing a prospective study was carried out to observe whether infection rates had changed and which factors continued to predict drain-related infections. Retrospective analysis identified 234 procedures in 159 patients over a two-year period. There were 54 drain-related infections, a rate of 21.5 per 1000 drainage days. Duration of CSF drainage [odds ratio (OR)=1.15, P<0.05] and the number of CSF samples taken per drain (OR=5.98, P<0.05) were independently associated with infection. In the prospectively gathered phase, 132 procedures were recorded in 107 patients over a one-year period. There were 18 infections, a rate of 13.7 per 1000 drainage days. The only independent prognostic factor was duration of CSF drainage (OR=1.20, P<0.05). Coagulase-negative staphylococci were the most commonly isolated type of organism in both series. Ensuring drains are removed promptly as soon as CSF diversion is no longer required may reduce the rate of nosocomial infections in this population despite multiple confounding factors. Institutional guidelines may promote best practice in this regard.