Intraventricular Hemorrhage & Hydrocephalus

Intraventricular Hemorrhage and Hydrocephalus

Blood, Obstruction, and CSF Circulation

CSF is produced predominantly by the choroid plexus, passes through the lateral ventricles, foramina of Monro, third ventricle, aqueduct, and fourth ventricular outlets, and reaches subarachnoid spaces. Resorption includes arachnoid and lymphatic pathways. Blood can obstruct a narrow passage acutely and can later impair resorption through inflammatory changes. Hydrocephalus may therefore be obstructive, communicating, or mixed over time. A patient who initially needs temporary drainage may later develop permanent shunt dependence.

Secondary IVH occurs when a parenchymal hemorrhage extends into the ventricles; thalamic and caudate locations are particularly close to ventricular structures. Primary IVH without a parenchymal source warrants assessment for vascular or other causes according to the clinical context. Describe which ventricles are involved, clot burden, third and fourth ventricular obstruction, ventricular enlargement, and transependymal flow. IVH severity scales such as the modified Graeb score support standardized description but do not replace assessment of the patient.

Declining consciousness, headache, vomiting, abducens weakness, and worsening brainstem signs can indicate hydrocephalus. Dorsal midbrain compression can produce impaired upgaze, light-near dissociation, convergence-retraction movements, or lid retraction. Not every feature must be present. Cushing physiology is a late danger signal rather than a required diagnostic triad. Reassess urgently when the examination changes, including repeat imaging and evaluation for seizure, rebleeding, systemic instability, or medication effects.

When and How to Drain

Ventricular drainage is recommended for ICH/IVH-associated hydrocephalus contributing to reduced consciousness. Coordinate neurosurgical placement, relevant coagulopathy correction, airway support, and treatment of herniation when present. An EVD can both divert CSF and measure pressure, but it is an invasive device with bleeding, infection, obstruction, and overdrainage risks. Placement and management require trained personnel and a documented protocol.

Set the prescribed reference at the appropriate approximation of the foramen of Monro, commonly the tragus/external auditory reference in the specified position. Relevel after changes in head or bed position. Drainage height is often ordered in cm H2O, while displayed ICP commonly uses mm Hg; one mm Hg is approximately 1.36 cm H2O. A drain height of 15 cm H2O corresponds to approximately 11 mm Hg, but the height is a hydrostatic drainage threshold rather than a guarantee that intracranial pressure always equals that number.

Specify continuous drainage, intermittent drainage, and measurement intervals explicitly. In a conventional system, an open drain affects the pressure signal; obtain a valid closed-system measurement according to protocol rather than reporting an open-drain value as undisturbed ventricular pressure. Some systems or a separate parenchymal monitor allow different configurations. Continuous and intermittent strategies have different goals and evidence across diseases. Do not claim that one approach always prevents infection, obstruction, or shunt dependence.

Troubleshoot Without Causing Injury

If output stops or the waveform changes, assess consciousness, pupils, symptoms, pressure, tubing, stopcocks, kinks, level, and the prescribed drainage threshold. No output can reflect obstruction, low pressure below the threshold, system error, or catheter position. Urgent CT and surgical review may be needed. Do not blindly aspirate, advance, or forcefully flush toward the patient. Manipulation requires the appropriately trained operator and the specific sterile protocol.

Unexpectedly high output, new positional headache, or neurologic change can indicate overdrainage. Recheck level and positioning and seek immediate direction. Excessive drainage can cause ventricular collapse, subdural collections, intracranial hypotension, and harmful compartmental gradients. Posterior fossa lesions require particular care, but selected cerebellar-infarction hydrocephalus can be managed by ventriculostomy; ongoing brainstem compression or deterioration changes the decompression decision.

Use sterile insertion and a closed system, avoid unnecessary sampling and manipulation, inspect for leak and infection, and remove the drain when no longer needed. Routine fixed-interval catheter exchange is not recommended for infection prevention. Suspected ventriculitis requires clinical assessment and appropriate cultures; normal routine CSF indices do not reliably exclude it after hemorrhage or surgery.

Clot Lysis and the CLEAR III Evidence

CLEAR III enrolled selected patients with an EVD, stable hemorrhage, small parenchymal ICH, and obstructing IVH. Alteplase 1 mg every eight hours for up to twelve doses was compared with saline through a tightly controlled protocol. This research regimen is not permission for unsupervised instillation. Drug delivery, sterile technique, catheter dead space, drainage interruption, imaging stability, pressure tolerance, and stopping rules require a trained multidisciplinary protocol. The study's catheter closure after instillation was one hour, not an invented two-hour default.

The primary outcome, mRS 0–3 at 180 days, was 48% with alteplase versus 45% with saline and was not significantly improved. Mortality at 180 days was lower, 18% versus 29%, but more survivors had very severe disability. Symptomatic bleeding was similar, and ventriculitis was less frequent in the alteplase arm. Interpret both survival and disability rather than calling the intervention an established independence treatment. Associations between greater clot removal and better outcomes do not prove a universal residual-volume target or justify applying lysis to unstable hemorrhage or an untreated vascular lesion.

When the patient is ready, assess whether drainage remains necessary using a protocol for clamp trials or staged elevation, serial examination, and imaging when appropriate. Evidence favoring faster weaning is strongest in selected populations and does not establish one universal infection or shunt outcome for all IVH. A failed trial requires reassessment of reversible factors and the need for continued diversion or permanent shunting.

Sources: CLEAR III and IDSA device-associated CNS infection guideline.

Decision Review