gms | German Medical Science

Objective: Morbidity associated with subarachnoid hemorrhage (SAH) is largely due to three pathomechanisms. One mechanism is the acute bleeding with destruction of CNS tissue, the second is secondary vasospasm, and the third, communicating malresorptive hydrocephalus. Therefore, the most frequent surgical procedure for SAH is ventriculostomy which can be used both for drainage and ICP measurements. The purpose of our study was to retrospectively assess the ventriculostomy-related infections.

Methods: Of all patients (pts.) suffering a SAH in our institution between Jan-2003 to Dec-2009, 333 patients 1238 pts. underwent an external ventriculostomy. In the same period, 465 additional EVDs were performed for other indications and served as a control population. Demographic data, comorbidities, medical complications, procedure-related data and the microbiology, hematologic and CSF laboratory values were assessed. Ventriculitis was defined as at least twice positive bacteriological cultures. In comparison, contamination was defined as a single positive culture.

Results: An EVD-related infection and a contamination were each seen in each 7 of 333 pts, (2.2%). Compared to all other EVDs due to different indications, the infection rate in SAH pts. was not significant (2.3% vs. 4.5%). Due to subarachnoid blood, EVD changes were necessary in 99 pts. This did not, though, add significantly to the infection rate. A permanent shunt implantation was necessary in 208 of 333 pts. Among the pts. with infections/contaminations, 12 of 14 required shunting. 197 pts. underwent a craniotomy for clipping or decompression, 153 underwent a coiling procedure. As for EVD changes, an additional craniotomy did not significantly increase the risk for infection. However, the duration of external drainage correlated significantly with infections, but not with contaminations. Of the 7 infected cases, 4 had a pneumonia, 3 vasospasm, 3 hypertension displaying a 2–3 fold frequency compared to all SAH-related ventriculostomies. The most frequent bacteria were various strains of staphylococci.

Conclusions: EVD-related infections in SAH are lower compared to other indications. A high association existed with concomitant pneumonia, vasospasms and hypertension. Among all surgical factors, only the duration of external ventricular drainage was associated with increased infection rate.