Frailty in middle cranial fossa approach for encephalocele or cerebrospinal fluid leak repair

Objective: The modified 5-item frailty index (mFI-5) is a concise, comorbidity-based risk stratification tool that can predict adverse outcomes after surgery. The goal of this study was to understand the frailty of patients undergoing surgery for temporal encephalocele or cerebrospinal fluid (CSF) leak and the utility of mFI-5 for predicting increased post-operative outcomes. Methods: A retrospective review of adults with temporal encephalocele or CSF leak who underwent middle cranial fossa (MCF) approach craniotomies with or without mastoidectomy from January 2015 through August 2021 at a tertiary care academic medical center was performed. Patients who underwent additional surgeries or extended surgical approaches were excluded. The mFI-5 was calculated for all patients. Demographic and clinical data were obtained from the medical record. Results: Thirty-six patients underwent 40 MCF approach craniotomies for temporal encephalocele or CSF leak, including three revision cases and one patient with sequential bilateral operations. Mean age was 54.1 ± 10.8 years, and 66.7% were female. In the univariable regression analysis, mFI-5 score, age, and procedure time use were significantly associated with increased hospital length of stay (LOS) but not increased intensive care unit (ICU) LOS. Anesthesia time and lumbar drain were significantly associated with increased hospital LOS and ICU LOS, and they remained significantly associated with increased hospital LOS in the multivariable model. Conclusion: Frailty is associated with increased hospital LOS stay among patients undergoing MCF approach for CSF leak or encephalocele. Reducing anesthesia time and avoiding lumbar drain use are potentially modifiable risk factors that can reduce the LOS and associated costs. Level of Evidence: 4.