Development and Validation of a Nomogram Model for Assessing the Impact of Continuous Lumbar Drainage Volume on Prognosis in Patients with Acute Hydrocephalus After Aneurysmal Subarachnoid Hemorrhage

Purpose: This study aimed to analyze the influence of volume during continuous lumbar drainage on the prognosis of patients with acute hydrocephalus after aneurysmal subarachnoid hemorrhage (aSAH) and to develop and validate a prognostic nomogram model. Patients and Methods: The clinical data of patients with acute hydrocephalus after aSAH at a single center were retrospectively collected. The modified Rankin Scale score at 6 months after discharge was used as the prognostic outcome. Clinical data were included in the univariate analysis. Significant variables were incorporated into a multivariate logistic regression analysis. On the basis of the independent factors identified, an individualized prognostic nomogram was developed and internally validated. Results: In total, 164 patients were included. Multivariate analysis revealed high World Federation of Neurological Surgeons scores (OR: 3.20), high modified Fisher grades (OR: 3.39), shunt dependence (OR: 8.05), and cerebral vasospasm (OR: 22.65) as independent risk factors for poor prognosis. Continuous lumbar drainage volume (OR: 0.61) was determined to be an independent protective factor. A nomogram model incorporating these independent factors was successfully constructed. The model demonstrated good predictive performance, with area under the receiver operating characteristic curve values greater than 0.86 in the training and test sets. Internal validation indicated high discriminative ability (C-index: 0.935) and good calibration. Conclusion: Increasing the volume of continuous lumbar drainage within the patient’s tolerance range is an independent protective factor. The nomogram effectively integrates multiple independent factors and provides a potentially effective reference tool for individualized prognosis prediction in patients with acute hydrocephalus after aSAH. Keywords: aneurysm, subarachnoid hemorrhage, hydrocephalus, lumbar drainage, prognosis, nomogram