Since the publication of guidelines for managing idiopathic normal pressure hydrocephalus (iNPH) in 2004, an increasing number of patients with iNPH have been undergoing shunt surgery in Japan. However, shunt surgeries for iNPH can be challenging because the procedures are performed on elderly patients. General anesthesia-related risks, such as postoperative pneumonia or delirium, are higher in the elderly. To decrease these risks, we applied spinal anesthesia on a lumboperitoneal shunt (LPS). Herein, we analyzed our methods focusing on the postoperative outcomes. We retrospectively analyzed 79 patients who underwent LPS at our institution with more than one year of follow-up. The patients were divided into two groups based on the anesthetic approach, that is, 1) general anesthesia and 2) spinal anesthesia, and were examined in terms of postoperative complications, delirium, and postoperative hospital stay. In the general anesthesia group, two patients had respiratory complications after the surgery. The postoperative delirium score using the intensive care delirium screening checklist (ICDSC) was 0 (2) (median [interquartile range]), and the length of postoperative hospital stay was 11 (4) days. In the spinal anesthesia group, no patients had respiratory complications. The postoperative mean ICDSC was 0 (1), and the length of postoperative hospital stay was 10 (3) days. Although there was no significant difference regarding postoperative delirium existed, LPS under spinal anesthesia decreased respiratory complications and significantly shortened the postoperative hospital stay. LPS under spinal anesthesia could be an alternative to general anesthesia in elderly patients with iNPH and possibly lessen the general anesthesia-related risks.
