The need for an institution-specific normal pressure hydrocephalus management protocol

Abstract

Background: Despite the publication of international guidelines, the management of normal pressure hydrocephalus (NPH) varies due to clinician preference and varying clinical evidence. An audit was performed to review the current pathways used in clinical practice with the aim of formulating an institution-specific protocol to optimize and standardize care.

Methods: An internal audit was performed on the management of patients with NPH who presented to the Princess Alexandra Hospital, Brisbane between January 2016 and February 2019.

Results: Forty-one patients were included in the study. Lumbar puncture (LP) was the main diagnostic test used (63.4%). About 14.6% underwent lumbar drain (LD) insertion instead. About 12.2% did not undergo either LP or LD before definitive treatment. Only 60% of all patients underwent ventriculoperitoneal shunt insertion. Overall, five treatment pathways were noted. LP + VP shunt showed the greatest average improvement in Montreal Cognitive Assessment (MoCA) or Mini-Mental State Examination (MMSE) (+3.8 ± 3.18), followed by LD + VP shunt (+3.25 ± 3.52) and sole treatment with LP (+1.83 ± 1.18). Both pre and post intervention assessment of gait and cognition were only performed in 31% and 48.8% of patients, respectively. Four types of cognitive assessment were used (MOCA 46.4%, MMSE 46.4%, Rowland Universal Dementia Assessment Scale 3.6%, and Addenbrooke's Cognitive Examination-III 3.6%). MoCA showed greater cognition improvement (2.07) compared to MMSE (1.3) post intervention. There was no consistent objective gait assessment test used.

Conclusion: The multiple NPH treatment pathways, low rate of pre and post objective symptom assessment, and lack of standardized gait and cognitive assessment tests demonstrate a clear need for an institution-specific NPH management protocol to standardize diagnostic workup, definitive management, and allied health assessment.

Keywords: Diagnosis; Normal pressure hydrocephalus; Protocol; Treatment.

Figure 1:

Distribution of treatment pathways, there were five treatment pathways noted: lumbar puncture (LP) only (26.8%), lumbar drain (LD) only (2.4%), ventriculoperitoneal shunt (VP) only (12.2%), LP + VP (36.6%), and LD + VP (12.5%).

Figure 2:

Distribution of cognitive assessments, there were four cognitive assessment tests used: Montreal Cognitive Assessment (MoCA, 46.3%), Mini-Mental Status Examination (MMSE, 41.5%), Rowland Universal Dementia Assessment Scale (RUDAS, 7.2%), and the Addenbrooke’s Cognitive Examination III (ACE-III, 4.8%).

Figure 3:

Approved normal pressure hydrocephalus management protocol.