Continuous Spinal Anesthesia in Frail Patients Undergoing Orthopedic Hip and Knee Revision Surgery: Advantages, Indications, and Risk Management-A Single-Center Retrospective Experience.

Background: Frail patients undergoing hip and knee revision surgery represent a major anesthetic challenge because of advanced age and multiple comorbidities. Continuous spinal anesthesia (CSA) with titrated low-dose levobupivacaine may offer a potentially useful alternative to general anesthesia or single-shot spinal anesthesia in this high-risk population. Methods: A retrospective review was conducted of ASA II-III patients who underwent complex hip and knee revision surgeries between February and October 2024 under CSA. The technique was performed using a 25-gauge spinal catheter with incremental boluses of 0.25% levobupivacaine (2.5 mg). Hemodynamic parameters, including mean arterial pressure (MAP), stroke volume index (SVI), and cardiac index (CI), were continuously monitored using the EV1000 hemodynamic monitoring system. Postoperative complications were recorded. Results: 37 high-risk patients were included in the study. Catheter placement was successful in all patients, with no conversions to general anesthesia. MAP decreased by a mean of 14.6% after boluses (p < 0.05); 9 patients (24.3%) experienced reductions ≥ 20%, but all remained >65 mmHg and responded to fluid therapy. CI and SVI decreased by 10.1% and 10.5%, respectively (p < 0.05), without clinical instability. No major complications (neurological injury, infection, post-dural puncture headache) were observed. Conclusions: In this retrospective single-center experience, CSA with titrated low-dose levobupivacaine was feasible and associated with stable hemodynamic profiles and a low rate of complications in frail patients undergoing complex lower-limb revision surgery. However, given the absence of a control group and the limited sample size, these findings should be interpreted cautiously. Further prospective comparative studies are needed to better define the role of CSA in high-risk orthopedic patients.