Association between the Rate of Intraoperative Crystalloid Infusion and Postoperative Outcomes in Older Patients Undergoing Spinal Surgery

Abstract

Summary of Background Data. – As old age affects postoperative outcomes; intraoperative management of geriatric patients should be well established. However, little evidence is available for optimization of fluid therapy during surgery in older patients. Objective. – To identify the effects of intraoperative fluid management on postoperative complications and 1-year morbidity among older patients undergoing spinal surgery. Study Design. – Retrospective cohort study. Methods. – We included patients aged ≥70 years who underwent spine surgery at the Department of Spine and Neurosurgery of our institution from January 2020 to December 2021 and were followed for 1 year (up to December 2022). The outcome measures were postoperative in-hospital complications and 1-year morbidity. The study sample was divided into three groups according to the rate of intraoperative crystalloid infusion: <4 mL/kg/h (restrictive), 4–8 mL/kg/h (moderate), and >8 mL/kg/h (liberal). Logistic regression analysis was conducted to investigate the association between perioperative factors and outcome measures. We performed a sensitivity test with inverse probability of treatment weighting (IPTW) to adjust for selection bias. Results. – Among 1, 192 patients, 207 (17.4%) experienced postoperative in-hospital complications and 359 (30.1%) developed morbidities within 1 year of surgery. Upon multivariable logistic regression with IPTW analysis, the rate of intraoperative crystalloid infusion remained a risk factor for postoperative in-hospital complications (liberal group: odds ratio [OR]: 2.981, 95% confidence interval [CI]: 1.621–5.481, P<0.01, vs. restrictive group) and 1-year morbidity (moderate group: OR: 1.622, 95% CI: 1.049–2.510, P=0.030; liberal group: OR: 2.107, 95% CI: 1.336–3.323, P=0.001, vs. restrictive group). Conclusion. – Liberal fluid therapy was associated with a higher risk of postoperative in-hospital complications and 1-year morbidity compared with restrictive fluid therapy in patients aged ≥70 years who underwent spinal surgery. Further studies are necessary to verify our findings for the establishment of appropriate intraoperative fluid management for geriatric patients. © 2025 Wolters Kluwer Health, Inc. All rights reserved.