Do iatrogenic factors bias the placement of external ventricular catheters?--a single institute experience and review of the literature.

Placement of external ventricular drainage (EVD) catheters is the gold standard for managing acute hydrocephalus, but the range of complications varies in different studies. The objective of this present single institute study is to analyze iatrogenic factors, which may influence the EVD device placement and the patient's outcome. A total of 137 EVD placements in 120 patients at the University Hospital Zurich were analyzed retrospectively. Discriminative findings between the pre- and postoperative imaging were obtained and evaluated in detail with regards to the postoperative course, ventriculostomy-related infection, and acute neurological deterioration directly related to the EVD placement. These findings were correlated to iatrogenic factors including education level of the neurosurgeon and surgical setting. Overall EVD-related complication rate was 16.1%, including infection rate of 10.2%, catheter malplacement rate of 2.2%, and hemorrhage rate of 3.6%. Although not statistically significant, catheter-associated hemorrhages and malplacements were found mostly in primary EVD surgery, with a higher complication rate associated with junior residents as the performing surgeon. In contrast, ventriculostomy-related infection was most likely present in patients with more than one EVD placement and in patients treated by more experienced physicians. Complications related to EVD are common. The rate and character of the complication depends on the education level of the surgeon.