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Updated: Jan 21, 2026

Double Direct Injection of Blood into the Cisterna Magna as a Model of Subarachnoid Hemorrhage
Published on: August 30, 2020
Standardized Ventriculostomy Protocol without an Occlusive Dressing: Results of an Observational Study in Patients
Joshua S Catapano1, Nicolas C Rubel1, Damjan Veljanoski1
1Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.
Background:
Catheter-related infections are a potentially life-threatening complication of having an external ventricular drain (EVD). Patients with aneurysmal subarachnoid hemorrhage (aSAH) are at increased risk of infection associated with prolonged ventricular drainage, with a reported mean infection rate of 6%. We report the EVD-associated infection rate among patients with aSAH managed with a unique standardized treatment protocol without an occlusive EVD dressing.
Methods:
Patients with aSAH admitted from August 2015 through August 2017 were retrospectively analyzed for EVD placement. Cerebrospinal fluid (CSF) samples were obtained twice weekly for culture and routine studies. EVD-associated infection was defined as growth of CSF cultures.
Results:
During the 2-year study period, 122 patients presented with an aSAH, with 91 (74.6%) having EVD placement. In patients with EVDs, the mean age was 57.9 years (68% women); 88% of aSAHs were Fisher grade III or IV. Mean duration of EVD was 14 days, and 13% of patients required EVD replacement. Endovascular coiling and surgical clipping were performed in 34 (37%) and 53 (58%) patients with EVD, respectively. A total of 347 CSF studies were performed with no EVD-associated infections. There were 3 CSF samples with false-positive Gram stain results but no growth on concurrent or multiple repeat cultures.
Conclusions:
Using a standardized protocol for placement and management of EVDs in patients with aSAH is associated with low risk of CSF infection. Our study demonstrates that occlusive EVD dressings are not necessary and that routine CSF sampling in patients with EVD may lead to false-positive findings and unnecessary antibiotic administration.
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