Analysis of the Effect of Initial External Ventricular Drainage in Patients with Aneurysmal Subarachnoid Hemorrhage on the Late Onset of Hydrocephalus

Lee, Jung Hoon; Kwon, Jeong Taik; Kim, Young Baeg; Suk, Jong Sik

Abstract

OBJECTIVE
The incidence and pathophysiologic mechanisms of chronic hydrocephalus requiring shunting after aneurysmal subarachnoid hemorrhage(SAH) is not precisely known. Authors investigated whether the initial external ventricular drainage in patients with aneurysmal subarachnoid hemorrhage can effect on the late onset of shunt-dependent hydrocephalus.
METHODS
In this prospective nonrandomized study, 311 patients with aneurysmal SAH treated using either surgical clip application or endovascular coil embolization were studied between Jan 2004 and Dec 2006. Chronic hydrocephalus was defined as clinically and radiographically demonstrated hydrocephalus that lasted 2 weeks or longer after the subarachnoid hemorrhage. 128 patients underwent perioperative extracranial ventricular drainage to allow brain relaxation and to drain intraventricular hematoma. The occurrence of asymptomatic and shunt-dependent hydrocephalus was analyzed in both treatment groups. Patients clinical grade was evaluated with WFNS (World Federation of Neurosurgical Societies) Grades, and Fisher Grades was used for evaluating radiological condition of the patient.
RESULTS
Among 128 patients, who underwent perioperative EVD, total 76 patients diagnosed as hydrocephalus later, and 23 patients needed shunt operation. The occurrence of hydrocephalus was significantly higher in patients underwent perioperative EVD (p<0.001), but there were no statistical significance between the perioperative EVD and the onset of shunt-dependent hydrocephalus (p=0.190). Among variable factors, Fisher grade, WFNS grade, amount of IVH on admission, and site of ruptured aneurysm showed statistical significance in related with the shunt-dependent hydrocephalus. Results of logistic regression analyses, perioperative EVD carried low risk of hydrocephalus (OR 0.408, 95% CI 0.224-0.745), but no statistically significant risk was shown related with the onset of shunt-dependent hydrocephalus.
CONCLUSION
As a result of this study, perioperative EVD in patients with aneurysmal SAH identified as a risk factor of the hydrocephalus. But there were no statistical significance as a risk factor of the shuntdependent hydrocephalus. Poor clinical and radiological status showed higher valuable risk of the shunt-dependent hydrocephalus rather than perioperative EVD. No hesitation seems to be needed for the perioperative EVD, especially in patients with poor neurological and radiological condition.