Complications in Patients Undergoing Microsurgical Clipping of Intracranial Aneurysms with Pre-existing Ventriculoperitoneal Shunts Following a Cranial Procedure

https://doi.org/10.1016/j.jstrokecerebrovasdis.2018.11.034Get rights and content

Abstract

Introduction: Patients with ventriculoperitoneal/pleural (VP) shunts occasionally must undergo subsequent craniotomy, craniectomy, or cranioplasty. Due to changes in pressure dynamics following shunt placement, we hypothesized that such patients may have an increased risk of developing symptomatic collections of extra-axial blood, fluid, and/or air postoperatively, leading to longer stays and worse outcomes compared to those undergoing cranial operations without a VP shunt.

Methods: From a retrospective cohort of patients who underwent cranial operations for management of cerebral aneurysms in 2005-2014, we identified patients who previously had a VP shunt placed, determined the temporal relationship between shunt placement and cranial operation, and investigated outcomes in those with and without a shunt.

Results: Of 818 patients who underwent cranial operations, 28 (3.4%) had a VP shunt. Four of these 28 (14.3%, 95% confidence interval [CI] 4.0%-32.7%) developed postoperative complications, compared to 42 of 790 (5.3%, 95% CI 4.0%-7.1%) without a history of VP shunt (P = .07). In addition, patients with a shunt were more likely to have longer cranial procedures (P = .04), longer hospital stays (P = .05), and more computed tomography scans during their craniotomy-associated admission (P = .002). Multivariate analysis, though not significant, demonstrated that the presence of a shunt contributed to the development of complications (odds ratio [OR] 2.24, 95% CI .70-7.13, P = .17). Length of surgery (OR 1.17, 95% CI 1.04-1.31, P = .01) and length of stay (OR 1.04, 95% CI 1.01-1.07, P = .01) were significantly longer in those with a postoperative complication.

Conclusion: We found a nonsignificant trend toward increased postoperative complications in patients with a VP shunt who underwent a subsequent cranial operation.

Introduction

Ventricular shunting is a routine neurosurgical procedure for conditions that require cerebrospinal fluid (CSF) diversion, including congenital hydrocephalus, normal pressure hydrocephalus, pseudotumor cerebri, and acquired hydrocephalus, secondary to conditions such as subarachnoid hemorrhage (SAH), trauma, infection, and mass occupying lesions.1, 2 The most common type of ventricular shunt placed is a ventriculoperitoneal (VP) shunt. Although commonly performed, VP shunting is not without complications. In fact, single-center studies investigating shunt-related complications have reported a major complication rate of 17.1%, overall complication rate of 58%, and shunt reoperation rates ranging from 17% to 69%.3, 4, 5 Examples of complications include intracerebral hemorrhage, mechanical dysfunction, and shunt infection.

VP shunt-related CSF diversion alters pressure and fluid dynamics within the brain.6, 7, 8 These alterations have the potential to complicate future cranial operations, a not uncommon occurrence for patients harboring vascular or tumor-associated pathologies. We postulated that the alteration of pressure and fluid dynamics from CSF diversion could potentially put patients undergoing subsequent cranial operations at higher risk of complications.

The purpose of this study was to determine whether patients with VP shunts are at increased risk of complications in subsequent neurosurgical cranial operations. To standardize the cohort, we chose to examine patients whose initial cranial operation was for the management of a cerebral aneurysm. We hypothesized that such patients may be at an increased risk of developing symptomatic hemorrhages, hygromas, or infections due to enlargement of epidural and subdural potential spaces initially created during the cranial procedure.9

Section snippets

Study Design

We performed a retrospective cohort study of all patients undergoing a cranial operation for management of cerebral aneurysms. Patient medical record numbers were collected through the University of Michigan Data Office for Clinical and Translational Research. Approval for this study was obtained from the University of Michigan Institutional Review Board.

Patient Selection

Adult patients (≥18 years old) who presented for cerebral aneurysm clipping from January 1, 2005 through December 31, 2014 with Current

Results

Of the 818 patients who underwent cranial operations for aneurysm clipping, 71.8% were females and the average age was 52.7 ± 10.8 years old. Twenty-eight (3.4%) of the patients with a cranial procedure had a VP shunt already in place at the time of their cranial operation. Over 98% of clipped aneurysms were anterior circulation aneurysms; aneurysm location was not associated with the presence of a postoperative complication. Additional demographic and clinical data are given in Table 1.

In

Discussion

The placement of a VP shunt is a common neurosurgical procedure for the treatment of hydrocephalus and other CSF-related pathologies. Placement of a VP shunt has been shown to alter intracranial fluid dynamics, leading to potential collections within the epidural and subdural spaces.11 When comparing outcomes for cranial operations in patients with and without a previously placed VP shunt, we demonstrate a nonsignificant trend toward increased postoperative complications in shunted patients

Conclusion

We found a nonsignificant trend toward an increase in postoperative complications in patients with a VP shunt who underwent subsequent cranial procedures when compared to patients without a VP shunt.

References (15)

There are more references available in the full text version of this article.

Financial Support: None.

View full text