Review question
We reviewed evidence about the effect of different administration routes of antibiotics given to prevent shunt infection in people who received a cerebrospinal fluid shunt.
Background
People with hydrocephalus (an excessive amount of cerebrospinal fluid within the brain, due to a blockage within their brain cavities or in their reabsorbing system) can be treated by implanting a cerebrospinal fluid shunt. This shunt is a tube running from the brain to either the heart or the abdomen in order to drain the excessive amount of cerebrospinal fluid to other body compartments where it will be reabsorbed. One of the most common problems after the implantation is infection of the shunt. Patients become sick and in most cases the shunt needs to be removed and a new one needs to be implanted after the patient has recovered. In order to reduce the number of infections surgeons administer antibiotics before, during or after surgery, or in various combinations, in order to protect the patient against bacteria that can infect the shunt. These antibiotics can be administered in different ways: orally; intravenously; directly into the brain cavities; directly on the shunt; and via the implantation of antibiotic-impregnated shunt catheters.
Results
We included 11 studies up to January 2018 in this review, comprising a total of 1109 participants who had received a cerebrospinal fluid shunt for hydrocephalus. The majority of the included studies were small and of variable duration (from eight weeks to more than one year). We found that administration of antibiotics is effective in the prevention of shunt infections (very low quality evidence). As the included studies are few, the interventions used differed markedly and the certainty of the evidence for our outcomes was very low, our results prevented a clear conclusion as to what type of antibiotic and administration route is most effective in the prevention of shunt infection.
Antibiotic prophylaxis may have a positive effect on lowering the number of participants who had shunt infections. However, the quality of included studies was low and the effect is not consistent within the different routes of administration that have been analysed. It is therefore uncertain whether prevention of shunt infection varies by different antibiotic agents, different administration routes, timing and doses; or by characteristics of patients, e.g. children and adults. The results of the review should be seen as hypothesis-generating rather than definitive, and the results should be confirmed in adequately powered trials or large multicentre studies in order to obtain high-quality evidence in the field of ventricular shunt infection prevention.
The main complication of cerebrospinal fluid (CSF) shunt surgery is shunt infection. Prevention of these shunt infections consists of the perioperative use of antibiotics that can be administered in five different ways: orally; intravenously; intrathecally; topically; and via the implantation of antibiotic-impregnated shunt catheters.
To determine the effect of different routes of antibiotic prophylaxis (i.e. oral, intravenous, intrathecal, topical and via antibiotic-impregnated shunt catheters) on CSF-shunt infections in persons treated for hydrocephalus using internalised CSF shunts.
We conducted a systematic electronic search without restrictions on language, date or publication type. We performed the search on the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE and Embase, with the help of the Information Specialist of the Cochrane Multiple Sclerosis and Rare Diseases of the CNS Group. The search was performed in January 2018.
All randomised and quasi-randomised controlled trials that studied the effect of antibiotic prophylaxis, in any dose or administration route, for the prevention of CSF-shunt infection in patients that were treated with an internal cerebrospinal fluid shunt. Patients with external shunts were not eligible.
Two review authors independently extracted data from included studies. We resolved disagreements by discussion or by referral to an independent researcher within our department when necessary. Analyses were also performed by at least two authors.
We included a total of 11 small randomised controlled trials, containing 1109 participants, in this systematic review. Three of these studies included solely children, and the remaining eight included participants of all ages. Most studies were limited to the evaluation of ventriculoperitoneal shunts. However, five studies included participants with ventriculoatrial shunts, of which one study contained four participants with a subduroperitoneal shunt. We judged four out of 11 (36%) trials at unclear risk of bias, while the remaining seven trials (64%) scored high risk of bias in one or more of the components assessed.
We analysed all included studies in order to estimate the effect of antibiotic prophylaxis on the proportion of shunt infections regardless of administration route. Although the quality of evidence in these studies was low, there may be a positive effect of antibiotic prophylaxis on the number of participants who had shunt infections (RR 0.55, 95% CI 0.36 to 0.84), meaning a 55% reduction in the number of participants who had shunt infection compared with standard care or placebo.
Within the different administration routes, only within intravenous administration of antibiotic prophylaxis there may be evidence of an effect on the risk of shunt infections (RR 0.55, 95% CI 0.33 to 0.90). However, this was the only route that contained more than two studies (8 studies; 797 participants). Evidence was uncertain for both, intrathecal administration of antibiotics (RR 0.73, 95% CI 0.28 to 1.93, 2 studies; 797 participants; low quality evidence) and antibiotic impregnated catheters (RR 0.36, 95% CI 0.10 to 1.24, 1 study; 110 participants; very low quality evidence)