Successful weaning versus permanent cerebrospinal fluid diversion after aneurysmal subarachnoid hemorrhage: post hoc analysis of a Swiss multicenter study

Abstract

OBJECTIVE Acute hydrocephalus is a frequent complication after aneurysmal subarachnoid hemorrhage (aSAH). Among patients needing CSF diversion, some cannot be weaned. Little is known about the comparative neurological, neuropsychological, and health-related quality-of-life (HRQOL) outcomes in patients with successful and unsuccessful CSF weaning. The authors aimed to assess outcomes of patients by comparing those with successful and unsuccessful CSF weaning; the latter was defined as occurring in patients with permanent CSF diversion at 3 months post-aSAH. METHODS The authors included prospectively recruited alert (i.e., Glasgow Coma Scale score 13–15) patients with aSAH in this retrospective study from six Swiss neurovascular centers. Patients underwent serial neurological (National Institutes of Health Stroke Scale), neuropsychological (Montreal Cognitive Assessment), disability (modified Rankin Scale), and HRQOL (EuroQol-5D) examinations at < 72 hours, 14–28 days, and 3 months post-aSAH. RESULTS Of 126 included patients, 54 (42.9%) developed acute hydrocephalus needing CSF diversion, of whom 37 (68.5%) could be successfully weaned and 17 (31.5%) required permanent CSF diversion. Patients with unsuccessful weaning were older (64.5 vs 50.8 years, p = 0.003) and had a higher rate of intraventricular hemorrhage (52.9% vs 24.3%, p = 0.04). Patients who succeed in restoration of physiological CSF dynamics improve on average by 2 points on the Montreal Cognitive Assessment between 48–72 hours and 14–28 days, whereas those in whom weaning fails worsen by 4 points (adjusted coefficient 6.80, 95% CI 1.57–12.04, p = 0.01). They show better neuropsychological recovery between 48–72 hours and 3 months, compared to patients in whom weaning fails (adjusted coefficient 7.60, 95% CI 3.09–12.11, p = 0.02). Patients who receive permanent CSF diversion (ventriculoperitoneal shunt) show significant neuropsychological improvement thereafter, catching up the delay in neuropsychological improvement between 14–28 days and 3 months post-aSAH. Neurological, disability, and HRQOL outcomes at 3 months were similar. CONCLUSIONS These results show a temporary but clinically meaningful cognitive benefit in the first weeks after aSAH in successfully weaned patients. The resolution of this difference over time may be due to the positive effects of permanent CSF diversion and underlines its importance. Patients who do not show progressive neuropsychological improvement after weaning should be considered for repeat CT imaging to rule out chronic (untreated) hydrocephalus.

Editorial. Weaning external ventricular drains after aneurysmal subarachnoid hemorrhage: how should we measure success?

“…T he authors have presented a post hoc analysis from a prospective multicenter study undertaken to examine differences in neurocognitive function, disability, and health-related quality-of-life experience with successful and unsuccessful weaning from external ventricular drains (EVDs) for hydrocephalus in alert patients (Glasgow Coma Scale score [13][14][15] after aneurysmal subarachnoid hemorrhage (aSAH). 1 Of 126 patients treated between 2017 and 2020, 54 required insertion of an EVD. At the same time, 37 of the 54 patients were successfully weaned from their EVD, and 17 of 54 needed shunt treatment for their hydrocephalus.…”

“…7 In the current paper, the method for weaning EVDs was not done according to a particular standardized or randomized protocol. 1 Instead, it was a mix of approaches using either gradual weaning or rapid closure, and patients in whom weaning failed "received ventriculoperitoneal shunt insertion." 1 The literature regarding these two strategies for EVD weaning has more recently pointed to the superiority of rapid EVD weaning protocols [8][9][10][11] and was summarized in a systematic review and meta-analysis by Palasz et al in 2022, with a conclusion that "patients who underwent rapid EVD weaning had a shorter hospital length of stay and there was no clear clinical advantage in using gradual weaning."…”

“…1 Instead, it was a mix of approaches using either gradual weaning or rapid closure, and patients in whom weaning failed "received ventriculoperitoneal shunt insertion." 1 The literature regarding these two strategies for EVD weaning has more recently pointed to the superiority of rapid EVD weaning protocols [8][9][10][11] and was summarized in a systematic review and meta-analysis by Palasz et al in 2022, with a conclusion that "patients who underwent rapid EVD weaning had a shorter hospital length of stay and there was no clear clinical advantage in using gradual weaning." 12 Exceptions may exist with some situations, such as the patient with acute low-pressure hydrocephalus, which can occur in a subset of patients after aSAH.…”

“…13 In the current paper the authors indicate that the EVD weaning decision was "left to the treating physicians' preference." 1 The discordance between the existing evidence and current practice has been highlighted by Chung et al in a 2017 survey that reported that the majority of centers still used gradual EVD weaning, 14 and these investigators emphasized in a 2018 review that "the argument for an early clamp and intermittent drainage, when possible, is most compelling, given the available evidence," calling for "more studies on the optimal management of EVDs" through multicenter prospective studies. 15 Although the answer regarding the best approach to EVD weaning may not be universally agreed upon, and reasonable equipoise existed, as indicated by El-Garci et al 1 in the current paper, it would have strengthened their study methodology and analysis if they had randomized patients between EVD weaning strategies.…”