From the Guidelines
For patients with normal pressure hydrocephalus (NPH), blood pressure should generally be maintained within normal ranges (typically below 140/90 mmHg), but management should be individualized to ensure a cerebral perfusion pressure (CPP) ≥ 60 mmHg, as recommended by the most recent guidelines 1.
Key Considerations
- Aggressive blood pressure lowering should be avoided as it may compromise cerebral perfusion in NPH patients, who often have altered cerebral autoregulation.
- If hypertension treatment is necessary, gradual reduction is preferred using medications that don't significantly reduce cerebral blood flow, such as angiotensin-converting enzyme inhibitors (like lisinopril) or angiotensin receptor blockers (like losartan) 1.
- Beta-blockers may be used cautiously, and blood pressure should be monitored regularly, especially after shunt placement, as over-drainage can lead to postural hypotension.
Management Goals
- The goal is to balance hypertension management with maintaining adequate cerebral perfusion pressure, as NPH patients rely on sufficient pressure gradients for proper CSF dynamics and brain perfusion.
- Any significant drops in blood pressure should be addressed promptly to prevent worsening of NPH symptoms like gait disturbance, cognitive decline, or urinary incontinence.
Individualized Approach
- The value of CPP should be adjusted (individualized) based on neuromonitoring data and the cerebral autoregulation status of the individual patient, as recommended by the guidelines 1.
- A stepwise approach may be used in cases of elevated ICP, reserving more aggressive interventions for situations when no response is observed 1.
From the Research
Blood Pressure Management in NPH Patients
There is no direct evidence in the provided studies to suggest a specific blood pressure range for patients with Normal-Pressure Hydrocephalus (NPH) 2, 3, 4.
Current Understanding of NPH
- NPH is a potentially reversible syndrome characterized by enlarged cerebral ventricles, cognitive impairment, gait apraxia, and urinary incontinence 2.
- The clinical and imaging features of NPH may be incomplete or nonspecific, posing a diagnostic challenge for medical doctors 2.
- Recent advances in non-invasive MRI methods and the frequent association of NPH with obstructive sleep apnea (OSA) offer new avenues to understand and treat NPH 2.
Treatment and Management
- The tap test has a high positive predictive value as a predictor of therapeutic response to ventricular shunt treatment, but a negative test does not exclude the possibility of treatment 3.
- Low-dose acetazolamide treatment has been shown to reverse periventricular white matter hyperintensities in iNPH and may improve gait in some patients 4.