Catherine Miller and Daniel Guillaume
External ventricular drains (EVDs) are regularly used in pediatric neurosurgery for diagnostic and therapeutic purposes. Hemorrhage caused by placing an EVD is a common complication noted in the adult literature. In the pediatric literature, on the other hand, only a few articles have assessed the risk of hemorrhage with placement, and none have reported the occurrence of hemorrhage with removal of an EVD. The authors investigated the incidence of hemorrhage with both placement and removal of the EVD in a pediatric population.
After obtaining institutional review board approval, a comprehensive database was created to include all pediatric patients who required EVD placement between March 2008 and June 2014 at the authors’ institution. A retrospective chart review was completed, and all imaging was reviewed for evidence of hemorrhage with placement and removal of the EVD.
During the designated time period, 73 EVDs were placed in 63 patients (ages 2 weeks–17 years). Indications for EVD placement were as follows: shunt infection/malfunction (21), tumor (12), hydrocephalus (18), hemorrhage (12), edema (4), trauma (1), and other (5). Hemorrhage with placement was noted in 5 of the 50 patients who underwent imaging, with a volume ranging from 0.48 cm3 to 7.7 cm3. Thirty-two patients had imaging after EVD removal, and 7 of these patients were noted to have hemorrhage (volume range 0.012 cm3 to 81.5 cm3).
The authors found the incidence of hemorrhage at EVD placement to be 10%, and the incidence of hemorrhage on EVD removal to be 21.9% in those patients who underwent imaging after each event. Although none of the hemorrhages were of obvious clinical significance, these data can be useful in decision making, and in discussing the risks of EVDs with the patient’s family.
Catherine Miller and Ramachandra P. Tummala
External ventricular drains (EVDs) have an important role in the management of neurological disease, and their placement is a frequently performed neurosurgical procedure. Hemorrhage is a common complication of EVD placement and occurs more frequently than originally believed. There is also risk of hemorrhage with removal of an EVD, which has not been well described. The authors investigated the risk factors associated with placement and removal of EVDs at their institution.
A database was created including patients who required EVD placement from March 2008 to June 2014 at the University of Minnesota. A retrospective chart review was completed, and data were collected for each patient. All cranial imaging studies during the index hospitalization were reviewed to identify hemorrhages associated with either EVD placement or removal. The study was performed using a research protocol approved by the University of Minnesota's institutional review board.
Four hundred eighty-two EVDs were placed during the designated time period. Among the cases in which patients underwent imaging after the placement procedure, hemorrhage was found in 94 (21.6%). The hemorrhage volume ranged from 0.003 cm3 to 45.9 cm3 (mean [± SD] 1.96 ± 6.48 cm3). Two of these hemorrhages resulted in additional interventions: 1 surgical evacuation and 1 contralateral EVD. In 55 (22.5%) of the 244 cases in which imaging was performed after EVD removal, hemorrhage associated with removal was identified. The mean volume of these hemorrhages was 8.25 ± 20.34 cm3 (range 0.012–82.08 cm3). Two EVDs were replaced, and 1 patient died as a result of a large hemorrhage. Large hemorrhages (> 30 cm3) occurred in 2 patients on placement (0.46%) and in 5 patients on removal (2.0%). In this series, decreased platelet levels on admission and an increasing number of EVD placement attempts correlated with an increased risk of hemorrhage on placement. Only those with an EVD placed at bedside were more likely to have hemorrhage on EVD removal.
Multiple studies have reported varying EVD hemorrhage rates while very few studies have described hemorrhage secondary to EVD removal. This is the first reported analysis of risk factors associated with hemorrhage on EVD removal. Hemorrhages occur relatively frequently following EVD placement and removal, though clinical significance of these events seems to be low.
Catherine Miller, Daniel Guillaume, Kathryn Dusenbery, H. Brent Clark and Christopher Moertel
Brain tumors are the most common solid tumor in childhood, and astrocytomas account for the largest proportion of these tumors. Increasing sophistication in genetic testing has allowed for the detection of specific mutations within tumor subtypes that may represent targets for individualized tumor treatment. The mitogen-activating protein kinase (MAPK) pathway and, more specifically, BRAF mutations have been shown to be prevalent in pediatric pilocytic astrocytomas and may represent one such area to target. Herein, the authors describe 2 cases of inoperable, chemotherapy-resistant pediatric pilocytic astrocytomas with a documented response to trametinib, an MAPK pathway inhibitor. While these cases were not treated in the setting of a clinical trial, their data support further ongoing clinical trial investigation to evaluate the safety and efficacy of this agent in pediatric low-grade gliomas.