Lumbar drainage for the treatment of severe bacterial meningitis

Objective: To assess the safety and effectiveness of lumbar drains as adjuvant therapy in severe bacterial meningitis, and compare it to standard treatment. Design: A retrospective cohort study of all patients above the age of 18 years with bacterial meningitis and altered mental status admitted to the Montreal Neurological Hospital Intensive Care Unit from January 2000 to December 2010. Patients: Thirty-seven patients were identified using clinical and cerebrospinal fluid criteria. Patients were divided into lumbar drain (LD) (n = 11) and conventional therapy (no LD) (n = 26) groups. Measurements: Outcomes were assessed using meningitis-related mortality and the Glasgow Outcome Scale (GOS) at 1 and 3 months. Outcomes: All patients received broad-spectrum antibiotic therapy, 84 % received steroids. There was no significant difference in mean age, type of bacteria, or time from arrival in ER to initiation of therapy. There was significantly less co-morbidity (24 % healthy vs 18.1 %) and coma (GCS < 8 34.6 vs 54.5 %) in the conventional therapy group, as well as a longer duration of symptoms prior to admission (mean 1.34 ± 1.24 vs 2.19 ± 2.34 days). The mean opening pressure was high in all patients (20-55 cm H₂O in the LD and 12-60 cm H₂O in the no LD). Mean time from arrival in ER to insertion of the lumbar drain was 37 h. Lumbar drains were set for a maximum drainage of 10 cc/h and an ICP below 10 mmHg. Despite greater clinical severity, the LD group had 0 % mortality and 91 % of the patients achieved a GOS of 4-5. The non-LD group had 15.4 % mortality and only 60 % achieved a GOS of 4-5. No adverse events were associated with LD therapy. Conclusions: In this study, the use of lumbar drainage in adult patients with severe bacterial meningitis was safe, and likely contributed to the low mortality and morbidity.