A retrospective analysis of cerebrospinal fluid drainage volume in subarachnoid hemorrhage and the need for early or late ventriculoperitoneal shunt placement.

BACKGROUND

External ventricular drains (EVDs) are used to manage acute hydrocephalus and facilitate brain relaxation after subarachnoid hemorrhage (SAH). We conducted a retrospective study on the relationship between CSF drainage volume and requirement and timing (early vs. late) for ventriculoperitoneal shunt (VPS) placement after EVD removal. We also sought to examine what factors were associated with volume of CSF drainage.

METHODS

We performed a retrospective analysis of SAH patients who had an EVD placed between January 2008 and June 2012 at Massachusetts General Hospital. Clinical and laboratory variables were abstracted from the medical record.

RESULTS

Of 97 patients, 19 failed an EVD clamp trial and had an early VPS placed and 10 had their EVD removed but subsequently required late VPS placement. Average CSF drainage volume per day was highest in patients who required early VPS (median of 201cc, interquartile range [IQR] 186-236) compared to those who did not require a VPS (median of 162cc, IQR 131-202) and those who required late VPS (median of 151cc, IQR 121-171) (P=0.002). There was a significant relationship between average CSF drainage volume per day and age (P=0.005) and sonographic vasospasm (P=0.006). After multivariate analysis, there was a significant relationship between VPS placement/timing and age (P=0.03) and average CSF output/day (P=<0.0001), and a trend towards significance with sonographic vasospasm (P=0.06).

CONCLUSIONS

High CSF output is associated with early VPS placement. Prospective research on targeted CSF drainage volume is warranted.