Failing to respond to systemic treatment or infection with a resistant organism might require intrathecal/intraventricular antibiotic administration. Choose the antimicrobial based on susceptibility. Dosages for intraventricular antibiotics:
○ Vancomycin: 5mg for slit ventricles, 10mg with normal-sized ventricles, 15–20mg for patients with enlarged ventricles.
○ Aminoglycoside: Dosing can also be tailored to ventricular size. Frequency can be adjusted based on drain output as well: once daily for drain output > 100 ml/day, every other day if drain output = 50–100 ml/day, every third day if drainage < 50 ml/day
– Gentamicin: 4–8mg
– Tobramycin: 5–20mg
– Amikacin: 5–30mg
○ Colistimethate sodium: 10mg CMS, which is 125,000 IU or 3.75mg CBA (Colistin Base units)
○ Daptomycin: 2–5mg
● After IT administration of an antimicrobial, clamp the drain for 15–60 minutes to allow the antimicrobial concentration to equilibrate in the CSF before opening the drain 7)
● Expert opinion: wait at least 7–10 days after the CSF cultures become sterile to implant a shunt if needed.
The objective of a study of Lakomkin et al. of the Mount Sinai Hospital, was to determine whether intraoperative injection of antibiotics is independently associated with reduced rates of infection and revision surgery in children undergoing shunt placement.
This was an analysis of a prospectively collected, multicenter, shunt-specific neurosurgical registry consisting of data from over 100 hospitals collected between 2016 and 2017. All patients under 18 yr of age undergoing first-time shunt placement for the definitive treatment of hydrocephalus were included. The primary exposure of interest was injection of intraventricular antibiotics into the shunt catheter following shunt placement and prior to closure. The use of additional surgical adjuncts, such as antibiotic-impregnated shunts, stereotactic guidance, and endoscopy was collected. The primary outcome metric was the need for additional intervention because of an infection.
A total of 2007 pediatric patients undergoing shunt placement for hydrocephalus were identified. Postoperatively, 97 (4.8%) patients had additional intervention secondary to infection. In a multivariable regression model controlling for patient characteristics, etiology of hydrocephalus, prior temporizing measures, and placement of an antibiotic-impregnated shunt, injection of intraventricular antibiotics was associated with a significant reduction in postoperative infections (odds ratio = 0.29, 95% CI: 0.04-0.89, P = .038). Of those receiving intraventricular antibiotics, only 2 (0.38%) went on to undergo re-intervention due to infection.
These data suggest that for this select group of patients, use of intraventricular antibiotics was associated with decreased rates of re-intervention secondary to infection. 8).