INTRODUCTION —
Intraventricular hemorrhage (IVH) is a type of intracranial hemorrhage characterized by bleeding in the cerebral ventricular system. Bleeding may be categorized as either primary IVH, confined to the ventricles, or secondary IVH, occurring as an extension of subarachnoid or intracerebral hemorrhage.
This topic discusses the causes, clinical presentation, diagnosis, and treatment of IVH that may occur in adults and children. IVH in the newborn is discussed separately. (See "Germinal matrix and intraventricular hemorrhage (GMH-IVH) in the newborn: Risk factors, clinical features, screening, and diagnosis" and "Germinal matrix and intraventricular hemorrhage (GMH-IVH) in the newborn: Management and outcome".)
Other forms of intracranial hemorrhage are discussed elsewhere:
●Intracerebral hemorrhage – (See "Spontaneous intracerebral hemorrhage: Pathogenesis, clinical features, and diagnosis" and "Spontaneous intracerebral hemorrhage: Acute treatment and prognosis" and "Spontaneous intracerebral hemorrhage: Secondary prevention and long-term prognosis".)
●Subarachnoid hemorrhage – (See "Aneurysmal subarachnoid hemorrhage: Epidemiology, risk factors, and pathogenesis" and "Aneurysmal subarachnoid hemorrhage: Clinical manifestations and diagnosis" and "Aneurysmal subarachnoid hemorrhage: Treatment and prognosis" and "Nonaneurysmal subarachnoid hemorrhage".)
●Subdural hematoma – (See "Subdural hematoma in adults: Etiology, clinical features, and diagnosis" and "Subdural hematoma in adults: Management and prognosis".)
●Epidural hematoma – (See "Intracranial epidural hematoma in adults".)
PATHOGENESIS AND CAUSES
Primary IVH — Primary IVH occurs when bleeding arises from a structure within or at the surface of the ventricles, such as the choroid plexus, subependymal zone of the brain parenchyma, or ventricular arteries and veins; bleeding occurs directly in the ventricular space (image 1) [1,2]. Bleeding in primary IVH is isolated to the ventricular system and does not involve intraparenchymal structures.
Primary IVH may be due to one of several conditions that impact the ventricular system.
●Hypertension – Rupture of small blood vessels at or within the brain parenchyma and immediately adjacent to the ventricle appears to be a common cause of primary IVH. Up to 50 percent of patients with cryptogenic primary IVH have chronic hypertension [3,4]. In these patients, primary IVH may occur by the same mechanism as hypertensive intracerebral hemorrhage.
However, the role of hypertension in primary IVH is conflicted as it has varied among different authors and studies. While most limit primary IVH to bleeding entirely localized within the ventricle, others have included hemorrhages that originate within 15 mm of the ependymal surface [5]. In addition, limitations in imaging may result in misclassification of intracerebral hemorrhage cases as primary IVH, such as earlier generation computed tomography (CT) studies and studies with imaging marred by motion artifact or mass effect from large-volume bleeding. These factors invariably result in some medial thalamic, caudate, and putaminal intracerebral hemorrhage (usually secondary to chronic hypertension) being attributed to primary rather than secondary IVH. (See "Spontaneous intracerebral hemorrhage: Pathogenesis, clinical features, and diagnosis", section on 'Hypertensive vasculopathy'.)
●Vascular causes – Among series that more strictly limit the definition of IVH to bleeding entirely within the ventricular system, vascular malformations are the most frequently identified cause of primary IVH. In small case series, vascular malformations have been identified in 14 to 58 percent of patients with primary IVH [3-9]. Vascular causes of primary IVH include:
•Vascular malformations (usually arteriovenous malformations or arteriovenous fistulas) (image 2 and image 3) [3-14]. (See "Brain arteriovenous malformations".)
•Intraventricular aneurysms occurring at the distal lenticulostriate or choroidal arteries [5,11,15,16]. These may be isolated findings or secondary to other vasculopathies such as moyamoya syndrome. Occasionally, aneurysms of the anterior communicating artery, posterior inferior cerebellar artery, or basilar tip rupture into the ventricles without other overt subarachnoid blood [5,6,8]. (See "Aneurysmal subarachnoid hemorrhage: Clinical manifestations and diagnosis".)
•Moyamoya disease and syndrome [6,10,11,15,17-20]. (See "Moyamoya disease and moyamoya syndrome: Etiology, clinical features, and diagnosis".)
•Cerebral vasculitis [21]. (See "Primary angiitis of the central nervous system in adults".)
•Fibromuscular dysplasia [5]. (See "Clinical manifestations and diagnosis of fibromuscular dysplasia".)
●Mass lesions
•Primary or metastatic neoplasm (eg, papilloma, neurocytoma, meningioma, astrocytoma, ependymoma) [3,15,22-27]. (See "Overview of the clinical features and diagnosis of brain tumors in adults".)
•Pituitary apoplexy [28]. (See "Causes, presentation, and evaluation of sellar masses", section on 'Causes'.)
●Systemic causes
•Coagulopathies, acquired or inherited [4-6,18,29-31]. (See "Thrombotic and hemorrhagic disorders due to abnormal fibrinolysis".)
•Sympathomimetic agents [32,33]. (See "Clinical manifestations, diagnosis, and management of the cardiovascular complications of cocaine use" and "Acute amphetamine and synthetic cathinone ("bath salt") intoxication", section on 'Central and peripheral nervous system'.)
•Herpes simplex infection [34]. (See "Herpes simplex virus type 1 encephalitis".)
●Cryptogenic – In approximately 20 to 50 percent of primary IVH, no identifiable cause of bleeding is found despite extensive evaluation [3,4,11,30]. Some of these cases may be due to hypertension leading to intracerebral hemorrhage at the ventricular surface.
Secondary IVH — Secondary IVH is due to the intraventricular expansion of a primary intracerebral hemorrhage or subarachnoid hemorrhage. Intraventricular extension of an intracerebral hemorrhage occurs when pressure from the acute hematoma causes expansion through the brain parenchyma into the ventricular space or leads to injury of ventricular vascular structures. Intraventricular extension of a subarachnoid hemorrhage occurs when acute blood in the subarachnoid space circulates into the ventricles with which it is contiguous (figure 1).
The pathogenesis of intracerebral and subarachnoid hemorrhage is discussed separately. (See "Spontaneous intracerebral hemorrhage: Pathogenesis, clinical features, and diagnosis", section on 'Pathogenesis and etiologies' and "Aneurysmal subarachnoid hemorrhage: Epidemiology, risk factors, and pathogenesis", section on 'Pathogenesis'.)
The underlying cause of secondary IVH from spontaneous subarachnoid hemorrhage is most commonly due to a ruptured cerebral aneurysm. Secondary IVH due to intracerebral hemorrhage may be related to diverse causes including hypertension, cerebral amyloid angiopathy, vascular malformations, and other entities. The underlying causes of spontaneous subarachnoid and intracerebral hemorrhage are discussed in greater detail separately. (See "Spontaneous intracerebral hemorrhage: Pathogenesis, clinical features, and diagnosis" and "Aneurysmal subarachnoid hemorrhage: Clinical manifestations and diagnosis" and "Nonaneurysmal subarachnoid hemorrhage".)
IVH can also complicate closed head injury. Usually, this is in the setting of other traumatic brain injuries, including contusion and traumatic subarachnoid hemorrhage; isolated IVH is a relatively rare complication of head trauma [35-37]. (See "Traumatic brain injury: Epidemiology, classification, and pathophysiology".)
EPIDEMIOLOGY —
Primary IVH is uncommon, accounting for only about 3 percent of all spontaneous intracerebral hemorrhage [10]. In a 2008 review of 356 published cases series of primary IVH, the median age of presentation was 55 years old with an age range from 9 to 91 years old [6]. Females constituted 49 percent of cases, and more than half of patients had a history of hypertension.
Secondary IVH is estimated to complicate 40 to 60 percent of intracerebral hemorrhage and 10 percent of aneurysmal subarachnoid hemorrhage cases [38-40]. The epidemiology of intracerebral hemorrhage and subarachnoid hemorrhage is discussed separately. (See "Spontaneous intracerebral hemorrhage: Pathogenesis, clinical features, and diagnosis", section on 'Epidemiology' and "Aneurysmal subarachnoid hemorrhage: Epidemiology, risk factors, and pathogenesis", section on 'Epidemiology'.)
CLINICAL FEATURES AND DIAGNOSIS
Clinical presentation — The clinical symptoms and signs of IVH reflect a sudden increase in intracranial pressure (ICP) that results from the introduction of blood volume into the intracranial space [41]. In addition to pressure effects, it is speculated that blood products in the cerebrospinal fluid (CSF) space may affect brain function.
●Headache and confusion – Patients with primary IVH typically present with an abrupt-onset headache, often associated with nausea, vomiting, and impaired consciousness (confusion, disorientation) [3,6,30,42]. A minority of patients have a frank loss of consciousness at the time of onset [4]. Symptoms are usually sudden in onset; however, nearly a quarter of patients are reported to have progressive or fluctuating onset of symptoms [3,4].
●Focal neurologic deficits – Focal neurologic findings are relatively uncommon with primary IVH and most typically involve cranial nerve abnormalities [5]. Such cranial nerve palsies are generally "false localizing" as they are typically caused by intracranial blood leading to stretching across the basilar skull surface rather than bleeding at the site of the nerve. Cranial nerves impacted in this setting may include the sixth and fourth nerves. The degree of neurologic impairment, often measured as the Glasgow Coma Scale (table 1), is an important prognostic indicator. (See 'Prognosis' below.)
Seizures are not common in IVH but can occur [3,5,10,12].
Neurologic deficits are more common in patients with secondary IVH due to subarachnoid or intracerebral bleeding. (See "Aneurysmal subarachnoid hemorrhage: Clinical manifestations and diagnosis", section on 'Clinical presentation' and "Spontaneous intracerebral hemorrhage: Pathogenesis, clinical features, and diagnosis", section on 'Clinical presentation'.)
●Examination findings – Most patients with IVH are hypertensive on presentation, and some will have an elevated body temperature or have cardiac arrhythmias [4]. Nuchal rigidity is inconsistently present.
Initial imaging features — The clinical features suggestive of IVH warrant urgent neuroimaging to evaluate for intracranial hemorrhage. Noncontrast head CT, the test of choice in this setting, rapidly and reliably identifies IVH by showing hyperdensity consistent with acute blood within the ventricular system (image 1). Head CT may also help to identify associated parenchymal intracerebral hemorrhage or subarachnoid hemorrhage (image 4), as well as the presence of concurrent hydrocephalus (image 5).
Brain magnetic resonance imaging (MRI) also readily identifies IVH and associated findings as well. MRI is less commonly performed as the initial imaging test for patients who present acutely with features suggestive of IVH but may occasionally identify IVH incidentally when performed to evaluate other conditions such as patients with encephalopathy.
Differential diagnosis — The differential diagnosis of IVH includes other conditions that present with an abrupt-onset headache with or without neurologic deficits as well as conditions that present with imaging findings that mimic intraventricular blood.
●Clinical mimics – The clinical presentation of IVH overlaps with those of subarachnoid hemorrhage and intracerebral hemorrhage. Head CT or other neuroimaging is used to discriminate these conditions.
Other cerebrovascular conditions that may present with an abrupt-onset headache also include reversible cerebral vasoconstriction syndrome, cervical artery dissection, posterior reversible leukoencephalopathy syndrome, and other less common causes of thunderclap headache (table 2). These conditions may be suspected when head CT shows no intraventricular blood and may be diagnosed by additional brain imaging such as brain MRI or vascular imaging such as CT- or magnetic resonance angiography (MRA) of the head and neck. (See "Overview of thunderclap headache".)
●Imaging mimics – Other entities that result in fluid collection in the intraventricular space may appear hyperdense on head CT similar to blood, such as infectious ventriculitis or prior intrathecal contrast administration. These conditions are typically identified by clinical circumstances such as the presence of an external ventricular drain or a history of preceding intrathecal procedure. When clinical circumstances are uncertain, these entities may also be discriminated from acute bleeding by specific findings on brain MRI [43,44]. Rare anatomic variants that also may appear on head CT as a blood-fluid level in the lateral ventricles may be identified by additional imaging such as brain MRI [45].
EVALUATION FOR UNDERLYING CAUSE —
We perform an evaluation to assess the etiology for all patients with an uncertain cause of IVH. Some patients with traumatic IVH may not require further evaluation if the mechanism of injury supports findings on initial diagnostic imaging.
Brain and vascular imaging
●Review initial head CT – Evaluation starts with a close examination of the initial head CT to assess for findings suggestive of an underlying cause such as intracerebral hemorrhage or aneurysmal subarachnoid hemorrhage. Findings suggestive of secondary IVH include evidence of bleeding within the brain parenchyma surrounding the ventricles (eg, caudate and thalamus) to indicate a primary intracerebral hemorrhage (image 4) or the presence of subarachnoid blood in the basal cisterns or cortical sulci to indicate subarachnoid hemorrhage with secondary IVH (image 2).
For patients with initial head CT features suggestive of a secondary IVH due to primary intracerebral hemorrhage or subarachnoid hemorrhage, we obtain further testing as indicated by the primary lesion. (See "Spontaneous intracerebral hemorrhage: Pathogenesis, clinical features, and diagnosis", section on 'Evaluation and diagnosis' and "Aneurysmal subarachnoid hemorrhage: Clinical manifestations and diagnosis", section on 'Identifying the source of bleeding'.)
For other patients with primary IVH or an uncertain cause, we obtain further brain and vascular imaging.
●MRI and vascular imaging – For patients with an uncertain cause of primary IVH, we typically start with brain MRI with contrast and either magnetic resonance angiography (MRA) or CT angiography to investigate for underlying causes such as vascular malformation (image 6 and image 7) or moyamoya syndrome (image 4). If the MRI/MRA or CT angiography is nondiagnostic, we perform digital subtraction angiography (DSA), in agreement with guidelines from the American Heart Association/American Stroke Association [46].
●Delayed repeat imaging – If acute imaging including DSA does not identify the cause of bleeding in primary IVH, we typically repeat brain MRI with contrast one to two months following the initial studies after reabsorption of blood products has occurred. We also repeat DSA if the MRI is unrevealing.
In a prospective observational study of patients with IVH who underwent catheter angiography, vascular lesions were found in 11 of 17 (65 percent), including 10 patients with arteriovenous malformations, and one with aneurysm [8]. A retrospective review of published case series similarly estimated the yield of angiography at 56 percent, additionally identifying cases of moyamoya syndrome and dural arteriovenous fistula [6].
Laboratory testing — We perform baseline laboratory testing for all patients with IVH including complete blood count and differential, electrolytes, blood clotting studies (prothrombin time, partial thromboplastin time, and platelet count), and a toxicology screen to assess for coagulopathic, sympathomimetic, or other systemic causes that may be contributory.
MANAGEMENT —
The treatment of IVH focuses on cessation of bleeding, close monitoring for and treatment of hydrocephalus and other causes of neurologic deterioration, treatment of underlying causes of bleeding, and prevention and management of medical complications.
Triage — Patients who have a moderate to severe IVH who are at elevated risk for complications (impaired alertness and/or extensive intraventricular blood on imaging) should be admitted to an intensive care unit (ICU) setting. This includes patients with acute IVH and any of the following features:
●Drowsiness or impaired alertness
●Focal neurologic deficits (eg, cranial nerve deficits, hemiparesis)
●Seizures
●Extensive intraventricular blood (eg, IVH volume >20 mL, IVH filling >25 percent of any ventricular compartment)
●Hydrocephalus
Management of antithrombotic medications
Patients on anticoagulation
●Indications for reversal – For most patients with IVH, we discontinue anticoagulant medications and give agents to reverse their effects. However, for some patients with small-volume acute IVH and no signs of hydrocephalus who are receiving anticoagulation for a compelling indication such as a mechanical heart valve, the risk-benefit calculation may favor continued anticoagulation with close observation of neurologic status.
Some patients prescribed anticoagulant medications may not require reversal agents if laboratory testing or the time interval since last dose indicates they are effectively not anticoagulated.
●Reversal strategies – If reversal of anticoagulation is indicated, the appropriate intervention varies according to the anticoagulant the patient is taking.
•Warfarin – Four-factor prothrombin complex concentrate (4F PCC) is preferred for patients with acute intracerebral hemorrhage taking warfarin. If 4F PCC is unavailable, three-factor prothrombin complex with recombinant activated factor VII or fresh frozen plasma (FFP) may be administered (table 3). Intravenous vitamin K should also be given to sustain the short-acting effects of 4F PCC or FFP. Reversal of anticoagulation in this setting is discussed in detail separately. (See "Reversal of anticoagulation in intracranial hemorrhage", section on 'Warfarin'.)
•Direct oral anticoagulants – Reversal strategies for direct oral anticoagulants (DOACs) differ by agent (table 4) and are presented separately. (See "Reversal of anticoagulation in intracranial hemorrhage", section on 'Dabigatran' and "Reversal of anticoagulation in intracranial hemorrhage", section on 'Apixaban, edoxaban, and rivaroxaban'.)
•Heparin and low-molecular-weight heparins – Protamine sulfate is recommended for urgent treatment of patients with heparin-associated intracerebral hemorrhage. The appropriate dose of protamine sulfate is dependent upon the type of heparin (unfractionated or low-molecular-weight agents), the dose of heparin given, and the time elapsed since that dose. Andexanet alfa may be used for patients taking low-molecular-weight heparin. (See "Reversal of anticoagulation in intracranial hemorrhage", section on 'Unfractionated heparin' and "Reversal of anticoagulation in intracranial hemorrhage", section on 'LMW heparin'.)
Strategies used for anticoagulation reversal in IVH are the same as those used for patients with intracerebral hemorrhage. These strategies are discussed in greater detail separately. (See "Reversal of anticoagulation in intracranial hemorrhage", section on 'Reversal strategy for specific anticoagulants'.)
●Patients continuing anticoagulation – For patients with IVH and a compelling indication to continue anticoagulation, we generally use intravenous heparin during the acute period given the ability to rapidly reverse its anticoagulant effect. (See "Anticoagulation for prosthetic heart valves: Management of bleeding and invasive procedures", section on 'Management of bleeding'.)
Patients on antiplatelet medication — For most patients with IVH, we typically stop antiplatelet medications at the time of diagnosis. However, we balance the thrombotic risks of discontinuation with the hemorrhagic risks of continuing antiplatelets at an individual level. We may continue antiplatelet medications during acute monitoring for selected patients at high risk of thrombosis such as those with established atherosclerotic disease or who have undergone intravascular stent placement and who have small IVH. (See "Prevention of cardiovascular disease events in those with established disease (secondary prevention)" and "Antithrombotic therapy for elective percutaneous coronary intervention: General use" and "Overview of carotid artery stenting" and "Endovascular techniques for lower extremity revascularization", section on 'Antiplatelet therapy'.)
We reserve platelet transfusions for those with specific indications, including those with thrombocytopenia (<100,000/microL) or a known platelet defect. (See "Platelet transfusion: Indications, ordering, and associated risks", section on 'Platelet function disorders'.)
Blood pressure management — The optimal blood pressure management in patients with IVH is uncertain. Aggressive blood pressure lowering may minimize the risk of further hemorrhage but must be weighed against the risk of decreased cerebral perfusion in patients with increased intracranial pressure (ICP).
In the absence of better data specific to IVH, we typically manage elevated blood pressure in IVH according to the guidelines outlined for blood pressure management in the setting of intracerebral hemorrhage [46]. (See "Spontaneous intracerebral hemorrhage: Acute treatment and prognosis", section on 'Blood pressure management'.)
The choice of antihypertensive agent and the rate of blood pressure lowering depends on local protocols and patient-level factors. Several intravenous medications may be used to control blood pressure in this setting including nicardipine, labetalol, clevidipine, esmolol, and enalaprilat (table 5). Nitroprusside and nitroglycerin are typically avoided because they may increase ICP. (See "Drugs used for the treatment of hypertensive emergencies".)
Monitoring for neurologic deterioration — Patients with acute primary or secondary IVH are at risk for sudden neurologic deterioration, which may result from obstructive hydrocephalus, recurrent hemorrhage, or other complications [4]. Close monitoring and supportive care may help prevent complications or quickly identify them so management strategies can be enacted to minimize morbidity.
Patients with acute IVH should be monitored clinically with neurologic examinations every two to four hours (or hourly for patients monitored in ICU settings) for the first few days after admission. Examinations may be performed less frequently for stable patients with improving symptoms who do not develop complications within the first two to four days. Limited retrospective data suggest deterioration due to hydrocephalus is most common within the first day after presentation, but later deterioration may also occur [47].
Patients whose neurologic examination deteriorates require repeat brain imaging or other diagnostic testing to determine the cause and guide subsequent treatment.
●Repeat head CT – An urgent repeat head CT is warranted for patients with IVH and an unexplained neurologic deterioration to identify recurrent hemorrhage or obstructive hydrocephalus. (See 'Hydrocephalus' below and 'Management of complications' below.)
Transcranial ultrasonography has been suggested as a possible alternative to serial CT to monitor ventricular size, but the reliability and reproducibility of this technique has yet to be independently validated [48].
●Additional testing – For patients with neurologic deterioration and stable repeat head CT, additional testing is warranted to assess for other complications. Specific testing varies by clinical circumstance and may include brain MRI and magnetic resonance angiography (MRA) to assess for ischemic stroke and/or cerebral vasospasm, laboratory testing for electrolyte disturbance, or electroencephalography to assess for seizures. (See 'Management of complications' below.)
Management of complications
Hydrocephalus — One-half to two-thirds of patients with IVH have some degree of hydrocephalus on the initial head CT [3,4,6,9,49]. Some of these patients will develop obstructive hydrocephalus. Acute obstructive hydrocephalus occurs when cerebrospinal fluid (CSF) circulation is blocked by a blood clot. Patients with blood in the third or fourth ventricle are at highest risk of this complication [4]. Obstructive hydrocephalus can be rapidly fatal and usually requires urgent intervention [36,41].
Patients may also develop communicating hydrocephalus as a delayed complication of IVH; this usually presents more gradually. (See 'Prognosis' below.)
External ventricular drain — Patients with IVH and neurologic deterioration that is due to new or worsening hydrocephalus will typically require an external ventricular drain (EVD). However, determining whether neurologic deterioration is attributable to hydrocephalus often requires clinical judgment. Patients with acute IVH may develop clinical worsening due to obstructive hydrocephalus as well as the development of other complications such as recurrent hemorrhage, vasospasm, or seizures. In addition, repeat imaging in some patients may show slight ventricular enlargement without obstruction of ventricular outflow which may be of dubious clinical significance.
Rarely, bilateral EVDs may be needed if hemorrhage in the lateral ventricles obstructs the foramen of Monro [50].
●Placement – An EVD is a small catheter inserted through the skull usually into the lateral ventricle, which is typically connected to a closed collecting device to allow for the drainage of CSF (figure 2). The procedure can be performed by neurosurgeons in the operating room or at the bedside. Intracranial access is gained via burr hole, frequently over the right frontal lobe. The catheter is inserted perpendicular to the surface of the skull and advanced to the midpupillary line to cannulate the lateral ventricle [51]. Other approaches may also be used. The EVD can then be connected to a transducer that records ICP.
●Management – An external valve is set to a target ICP pressure threshold (eg, 0 to 20 cm H2O at the level of the patient’s tragus) beyond which CSF drains into a collecting bag. CSF drainage may be continuous or intermittent but needs to be regulated to prevent rapid or excessive volume drainage that may lead to ventricular collapse, catheter occlusion, or hemorrhage [51]. Once symptoms and ICP improve, the drainage threshold may be increased and then temporarily clamped to assess for the potential to wean from the EVD. Patients who remain neurologically stable and do not develop worsening hydrocephalus on a subsequent head CT performed at 24-hour follow-up may be candidates for EVD removal. Patients with subsequent neurologic deterioration or worsening hydrocephalus may need further CSF drainage via the EVD or a transition to a permanent external CSF diversion system such as a ventriculoperitoneal shunt (figure 3). An inability to wean from the EVD can be a manifestation of the development of communicating hydrocephalus due to impairment of CSF resorption from the IVH. (See 'Prognosis' below.)
●Complications – The major complications associated with EVD are catheter occlusion due to clotted blood at the intraventricular orifice, intracranial bleeding with insertion, and shunt infection. Catheter occlusion may be relieved by irrigation or catheter replacement. Bleeding with EVD insertion may be suspected if neurologic deterioration occurs after insertion and can be identified by head CT. Management is symptomatic. Symptoms suggestive of infective ventriculitis should prompt CSF analysis for cell count and culture along with antibiotic therapy as appropriate. Staphylococci are the most common pathogens. Higher rates of bacterial ventriculitis/meningitis occur with a longer duration of EVD placement [52]. However, prophylactic catheter change does not reduce the risk of infection. The management and prevention of infections in patients with EVD are discussed in greater detail separately. (See "Infections of cerebrospinal fluid shunts".)
The evidence to support the use of EVD for acute IVH with hydrocephalus is limited to retrospective and cohort studies of patients with secondary IVH due to primary intracerebral hemorrhage which suggest that mortality may be lower in patients treated with an EVD [53-55]. Guidelines from the American Heart Association/American Stroke Association endorse the use of EVD for patients with IVH and hydrocephalus to reduce mortality by rapidly reducing life-threatening elevations in ICP [46].
Adjunctive options — In addition to EVD placement, adjunctive approaches have also been used for the prevention and treatment of hydrocephalus in IVH. These modalities are typically performed on an individual basis or in research settings at centers experienced with their use.
●Intraventricular thrombolysis — The utility of intraventricular thrombolysis (IVT) for patients with IVH and an EVD is uncertain. IVT use involves shared decision-making and includes discussing individual risks and benefits.
Instillation of thrombolytic agents into the ventricles may improve mortality by hastening clot resolution, thereby avoiding the morbidity associated with EVD occlusion and shortening the duration of EVD use. It is also possible, although unproven, that a more rapid resolution of IVH may decrease the long-term incidence of communicating hydrocephalus. However, IVT use may increase the risk of bleeding and severe disability. IVT is reserved for selected patients with acute IVH and an EVD at centers experienced with this approach.
Evidence supporting the use of IVT for EVD has been reported in case series, observational studies, and pooled analyses. These studies have suggested a benefit of IVT, showing increased clot resolution and, in some cases, decreased mortality [38,42,56-67]. The results of randomized clinical trials, on the other hand, have not shown clear benefit:
•The Clot Lysis: Evaluating Accelerated Resolution of Intraventricular Hemorrhage (CLEAR-III) trial included 500 patients with IVH and compared treatment with 1 mg alteplase (tPA) or placebo injected through an EVD every eight hours until clot reduction or a clinical endpoint occurred, or 12 doses were given [68]. At 180 days, the primary efficacy outcome of a modified Rankin scale (mRS) score of 3 or less was similar in each group (48 versus 45 percent comparing tPA to placebo; risk ratio [RR] 1.06, 95% CI 0.88-1.28). Patients who received IVT had lower mortality (18 versus 29 percent; RR 0.60, 95% CI 0.41-0.86) but a higher rate of severe disability indicated by an mRS score of 5 (17 versus 9 percent; RR 1.99, 95% CI 1.22-3.26). Bleeding complication rates were similar (2 percent) in both groups. One criticism of the CLEAR-III trial is that only a minority of patients experienced substantial IVT removal, suggesting the possibility of benefit with more effective methods for clot removal.
•The Intraventricular Hemorrhage Thrombolysis Trial, a multicenter randomized controlled study, enrolled 48 patients and compared IVT (3 mg tPA) to control (normal saline); each treatment was injected through an EVD every 12 hours until clot reduction or a clinical endpoint occurred (median duration of dosing was 7.5 days for IVT) [69]. The rate of clot resolution was faster for IVT than placebo (18 versus 8 percent per day). Rates of death and ventriculitis were lower than expected and did not differ significantly between treatment groups. Symptomatic bleeding complications were more frequent in the tPA group (23 versus 5 percent), but this did not reach statistical significance. The dose used in this study was higher than that used in the CLEAR-III trial.
Bleeding complications are a concern with IVT; recurrent IVH and/or intracerebral hemorrhage expansion are reported in 8 to 20 percent of patients after IVT [11,41,58,59,69,70]. Typically, patients with a known aneurysm or vascular malformation were excluded from early studies of IVT. However, IVT has been used without complication in some cases after the vascular malformation or aneurysm was surgically treated [11,71-73], and even before surgery in a few patients with these lesions [12,74]. Systemic bleeding complications are unlikely to be significantly increased with IVT; in CLEAR IVH, systemic coagulation parameters were similar after administration of tPA and placebo [75].
It is also possible that the risk of bacterial meningitis/ventriculitis may be increased with IVT therapy, but this has not been reported [41,58,68,69]. IVT has not been associated with systemic complications [76].
●Lumbar drainage — The use of lumbar drainage combined with an EVD and IVT was studied in an open-label trial that was stopped early after 30 patients were enrolled; patients with severe IVH with tamponade of the third and fourth ventricles requiring EVD were treated with IVT or IVT plus lumbar drainage [77]. The need for permanent shunt placement (primary endpoint) occurred in 7 out of 16 patients treated with IVT but 0 out of 14 of those treated with IVT plus lumbar drainage. In a meta-analysis that included patients in this study as well as an additional 67 patients treated outside of the clinical trial, IVT plus lumbar drainage was associated with a reduced rate of shunt dependency (odds ratio [OR] 0.24; 95% CI 0.01-0.36) [77]. This analysis found no significant differences in functional outcomes or CSF infection rates at 90 days; bleeding complications were less frequent in the combined treatment group.
Recurrent hemorrhage — Recurrent hemorrhage or hemorrhage extension occurs in up to 20 to 25 percent of patients with acute IVH [4,41,78,79]. Initial head CT findings associated with an elevated risk of IVH growth include irregular hemorrhage shape, intralesional hypodensity, and coexisting intraparenchymal hemorrhage [78,79]. The highest risk of this is in those with secondary IVH due to an underlying etiology such as vascular malformation or aneurysm or in the setting of coagulopathy.
Medical strategies to prevent and manage recurrent hemorrhage include blood pressure control and treatment of hydrocephalus. (See 'Blood pressure management' above and 'Hydrocephalus' above.)
Patients with IVH who have unexplained recurrent hemorrhage may also warrant prompt treatment of the underlying cause of bleeding or repeat cerebrovascular testing when the cause is uncertain. (See 'Treatment of underlying cause of bleeding' below and 'Brain and vascular imaging' above.)
Other complications
●Cerebral vasospasm – Cerebral ischemia due to arterial vasospasm is unusual in cases of primary IVH, but this complication has been described in isolated cases [14,80-82]. In contrast, vasospasm is a common complication of secondary IVH associated with aneurysmal subarachnoid hemorrhage. The treatment of vasospasm is discussed separately. (See "Aneurysmal subarachnoid hemorrhage: Treatment and prognosis", section on 'Vasospasm and delayed cerebral ischemia'.)
●Seizures – Seizures are an infrequent complication of most forms of IVH. For most patients with IVH, we do not use prophylactic antiseizure medications. For others with secondary IVH due to subarachnoid hemorrhage or traumatic brain injury, we manage patients according to the underlying cause. (See "Aneurysmal subarachnoid hemorrhage: Treatment and prognosis", section on 'Seizure prophylaxis' and "Management of acute moderate and severe traumatic brain injury", section on 'Antiseizure medications and electroencephalography monitoring'.)
For all patients with IVH who have a seizure, antiseizure medications should be administered to reduce the risk of recurrence. (See "Evaluation and management of the first seizure in adults".)
●Medical complications – Neurologic deterioration due to medical complications is common in the setting of IVH and requires appropriate monitoring and treatment [3,10]. Common complications of patients with IVH include:
•Fever and infection
•Myocardial ischemia or arrhythmias
•Aspiration and respiratory failure
•Venous thromboembolism and/or pulmonary embolism
•Acute kidney injury
•Gastrointestinal bleeding
•Electrolyte disturbance
These issues and their management are discussed in detail separately. (See "Complications of stroke: An overview".)
Treatment of underlying cause of bleeding — Interventions to prevent rebleeding and other cause-specific complications are individualized to the specific cause of IVH. (See 'Pathogenesis and causes' above.)
PROGNOSIS —
The prognosis of IVH varies according to several factors including the severity of symptoms at presentation, extent of bleeding, development of complications, underlying cause, and premorbid status.
●Mortality – The reported in-hospital mortality of IVH ranges from 20 to 50 percent [3-6,10,30,39,58]. Secondary IVH carries a higher risk of death than primary IVH [9,30,76].
●Morbidity – Recovery in survivors of IVH may be limited by the presence of long-term complications. These include:
•Neurocognitive sequelae – Patients with significant acute IVH are often confused, agitated, and disoriented [10]. These symptoms are often slow to recover, and approximately half of survivors are left with chronic cognitive deficits [3,10,11].
•Noncommunicating hydrocephalus – Intraventricular blood may cause a secondary inflammatory/fibrotic response at the cerebrospinal fluid (CSF)-brain barrier that leads to impaired CSF absorption at the arachnoid granulations. Clinically, this may manifest as a subacute decline in cognition, gait, and urinary continence that can occur weeks or later after the initial IVH. It may also present as a failure to wean off external ventricular drain (EVD). Such patients may require permanent ventriculoperitoneal shunt [41]. Approximately 30 to 50 percent of patients with IVH require a shunt placement [11,58,65,72,83-86]. Factors associated with shunt placement in patients with IVH include early elevation of intracranial pressure (ICP), high volume of CSF drainage, and use of multiple EVDs [87]. (See "Normal pressure hydrocephalus".)
•Late recurrence of IVH – Recurrent hemorrhage is uncommonly reported after IVH. In one series, 2 of 14 survivors had a subsequent intracerebral hemorrhage [4], while in another series, there was no recurrent bleeding in a group of 13 patients after 67 months [3]. The risk of this complication is likely highest in those with an unrecognized and/or unsecured vascular lesion (eg, moyamoya syndrome) [16,88].
●Prognostic factors – Older age, underlying coagulopathy, Glasgow Coma Scale score of 8 or less, and hydrocephalus at presentation are also associated with a higher risk of death with acute IVH [4,6,30,49,76]. While some studies have found that the extent of IVH correlates with prognosis [4,6,49,89], others have not [3,5,9]. The results of one study found that the volume of blood in the third ventricle was a strong and independent predictor of poor outcomes, while the volume of blood in the lateral ventricles, fourth ventricle, or entire ventricular system did not correlate significantly with prognosis [90]. The authors speculated that blood in the third ventricle may affect critical contiguous structures in the midbrain.
●Scoring systems – The extent of IVH on initial head CT can also be graded by head CT. The Graeb score and other scoring systems have been proposed [89,91,92], but none are widely implemented in clinical practice.
SOCIETY GUIDELINE LINKS —
Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Stroke in adults".)
SUMMARY AND RECOMMENDATIONS
●Terminology and causes – IVH is a type of intracranial hemorrhage characterized by bleeding in the cerebral ventricular system (figure 1). The two types of IVH are (see 'Introduction' above):
•Primary IVH – bleeding confined to the ventricles (image 1)
•Secondary IVH – bleeding in the ventricles as an extension of subarachnoid or intracerebral hemorrhage (image 4)
Primary IVH may be due to one of several etiologies including vascular malformation, hypertension, intraventricular aneurysm, moyamoya syndrome, vasculitis, neoplasm, and coagulopathy. Secondary IVH is most commonly due to trauma, aneurysmal subarachnoid hemorrhage, or spontaneous intracerebral hemorrhage. (See 'Pathogenesis and causes' above.)
●Clinical features – Patients with primary IVH typically present with abrupt-onset headache, often associated with nausea, vomiting, and impaired consciousness (confusion, disorientation). Focal neurologic findings typically involve cranial nerve abnormalities. (See 'Clinical presentation' above.)
Head CT rapidly and reliably identifies blood within the ventricular system to diagnose IVH (image 1), helps to identify any associated intracerebral hemorrhage or subarachnoid hemorrhage (image 4), and shows concurrent hydrocephalus if present (image 5). (See 'Initial imaging features' above.)
●Evaluation for underlying cause – Some patients with traumatic IVH may not require further evaluation if the mechanism of injury supports findings on CT. For other patients, we perform diagnostic testing including:
•Brain MRI with contrast and either magnetic resonance angiography (MRA) or CT angiography.
If the MRI/MRA or CT angiography is nondiagnostic, we perform digital subtraction angiography (DSA). (See 'Brain and vascular imaging' above.)
•Laboratory testing including complete blood count and differential, electrolytes, blood clotting, and a toxicology screen to assess for coagulopathic, sympathomimetic, or other systemic causes. (See 'Laboratory testing' above.)
●Management
•Antithrombotic medications – For most patients with IVH, we discontinue anticoagulant and antiplatelet medications and give agents to reverse anticoagulant effects. However, for some patients with small acute IVH and no signs of hydrocephalus who are receiving anticoagulation for a compelling indication such as a mechanical heart valve, the risk-benefit calculation may favor continued anticoagulation with close observation of neurologic status. (See 'Management of antithrombotic medications' above.)
•Blood pressure – We typically manage elevated blood pressure in IVH according to the guidelines outlined for blood pressure management in the setting of intracerebral hemorrhage. (See 'Blood pressure management' above.)
•Monitoring – Patients should be monitored with neurologic examinations every two to four hours (or hourly for patients monitored in intensive care settings) for the first few days after admission. Examinations may be performed less frequently for stable patients with improving symptoms and no complications within the first two to four days. (See 'Monitoring for neurologic deterioration' above.)
Deterioration of the neurologic examination mandates repeat brain imaging or other diagnostic testing to assess for the cause and guide subsequent treatment.
•Hydrocephalus – Patients with IVH and neurologic deterioration that is due to new or worsening hydrocephalus will typically require an external ventricular drain (EVD) (figure 2). However, determining whether neurologic deterioration is attributable to hydrocephalus often requires clinical judgment. Placement of an EVD to manage intracranial pressure (ICP) for patients with IVH and hydrocephalus may reduce mortality. (See 'External ventricular drain' above.)
●Prognosis – The prognosis of IVH varies according to several factors including the severity of symptoms at presentation, extent of bleeding, development of complications, underlying cause, and premorbid status. The reported in-hospital mortality of IVH ranges from 20 to 50 percent. Long-term complications of IVH include neurocognitive sequelae, noncommunicating hydrocephalus, and late recurrence of bleeding. (See 'Prognosis' above.)
ACKNOWLEDGMENT —
The UpToDate editorial staff acknowledges James Pacelli Jr, MD, who contributed to earlier versions of this topic review.