Permanent cerebrospinal fluid diversion in subarachnoid hemorrhage: Influence of physician practice style

Abstract

Background:Acute hydrocephalus (HCP) after aneurysmal subarachnoid hemorrhage (SAH) often persists. Our previous study described factors that singly and combined in a formula correlate with permanent CSF diversion. We now aimed to determine whether the same parameters are applicable at an institution with different HCP management practice.Methods:We reviewed records of 181 consecutive patients who presented with SAH and received an external ventricular drain (EVD) for acute HCP. After exclusion and inclusion criteria were met, 71 patients were analyzed. Data included admission Fisher and Hunt and Hess grades, aneurysm location, treatment modality, ventricle size, CSF cell counts and protein levels, length of stay (LOS) in the hospital, and the presence of craniectomy. Outcome measures were: (1) initial EVD challenge outcome; (2) shunting within 3 months; and (3) LOS.Results:Shunting correlated with Hunt and Hess grade, CSF protein, and the presence of craniectomy. The formula derived in our previous study demonstrated a weaker correlation with initial EVD challenge failure. Several parameters that correlated with shunting in the previous study were instead associated with LOS in this study.Conclusions:The decision to shunt depends on management choices in the context of a disease process that may improve over time. Based on the treatment strategy, the shunting rate may be lowered but LOS increased. Markers of disease severity in patients with HCP after SAH correlate with both shunt placement and LOS. This is the first study to directly evaluate the effect of different practice styles on the shunting rate. Differences in HCP management practices should inform the design of prospective studies.

Risk of Shunting After Aneurysmal Subarachnoid Hemorrhage

“…The review of the sparse literature on this matter offers a broad scope for improvement and a direction for future research that could lead to decreased shunt dependency in aSAH patients, by optimizing EVD management (indications, drainage, and weaning techniques) and understanding physiological changes after EVD placement. 30,31 Meningitis was an independent risk factor for shunt dependency in our series, and this association has also been found in other series. 4,7,17,23 Studies have proposed several mechanisms on how inflammation predisposes to delayed hydrocephalus.…”

The dilemma of complicated shunt valves: How to identify patients with posthemorrhagic hydrocephalus after aneurysmatic subarachnoid hemorrhage who will benefit from a simple valve?

“…[ 17 ] Unless the pathophysiology of neither iNPH nor pHC is unriddled, reduction of the ventricular width due to shunts in patients with communicating hydrocephalus seems to be unphysiological and does not correlate with a better outcome. [ 18 ]…”

Prediction of ventriculoperitoneal shunt placement based on type of failure during external ventricular drain wean

“…The relationship between aneurysm location [8,10-12], aneurysm size [8,12], and treatment method [8-10,12,15] and VPS requirement remains similarly controversial. While the variant findings may be due to limited sample sizes, an important factor may be the variation in EVD management [3-8] and decision making for VPS placement [3,6,9,10]. …”

“…Many other institutions employ a progressive weaning strategy whereby the EVD is gradually raised over multiple days then ultimately clamped, a process that is extrapolated from evidence about chest tube and endotracheal tube management [3,7,8]. While at some institutions, patients have multiple EVD challenges [9], at others, failure of a single EVD clamp trial results in placement of a ventriculoperitoneal shunt (VPS) [6], and at still others there are radiologic [10] or clinical criteria [3,6] for VPS placement without a clamp trial.…”

“…Previous studies that evaluated predictors of VPS placement explored a wide variety of variables, including age [8,10-12,14,15], sex [8,10-12], presence of comorbidities [15], intubation status on admission, initial Glasgow Coma Scale (GCS) [12,14], initial Hunt Hess [6,8-11,16] and Fisher scores [5,10,11,14,16,17], admission glucose [17], aneurysm location [8,10-12] aneurysm size [8,12] treatment method (clip versus coil) [9,10,12,15,16], third ventricle diameter at admission [6], intraventricular hemorrhage (IVH) [2,5,8,10,11,16], vasospasm [8], admission CSF red blood cells (RBC) and protein [6,9], ventriculitis [11,17], and number of EVD days [9]. Of these, the most reproducible factors include age, sex, Hunt Hess and Fisher scores, and the existence of many others suggests that local practice may influence the decision to place a VPS.…”