Perioperative Continuous Femoral Nerve Block Reduces Postoperative Cognitive Dysfunction of High-Risk Patients with Femoral Neck Fracture: Evidence from a Retrospective Propensity-Matched Study

Preoperative mild cognitive impairment as a risk factor of postoperative cognitive dysfunction in elderly patients undergoing spine surgery

Introduction

Any persistent degree of cognitive impairment in older adults is a concern as it can progress to dementia. This study aimed to determine the incidence and risk factors for early postoperative cognitive dysfunction (POCD) in elderly patients undergoing spine surgery.

Methods

Patients were enrolled from a previous prospective observational study after screening for normal cognitive function using the Mini Mental State Examination (MMSE). Cognitive function was evaluated before surgery and at 1 week, month, and year post-surgery using MMSE and Montreal Cognitive Assessment scores (MoCA). Mild cognitive impairment (MCI) was determined using the MoCA scores adjusted for age. POCD was defined as a drop of three or more points on the MMSE 1 week post-surgery. Multivariate logistic analysis was performed to identify POCD risk factors.

Results

A total of 427 patients were included. Eighty-five (20%) had pre-existing MCI. The MCI group showed lower MoCA scores at each time point (baseline, 1 week after surgery, 1 month after surgery, 1 year after surgery) compared to the non-MCI group. Those in the MCI group had a higher rate of admission to intensive care unit after surgery, postoperative delirium, and POCD 1 week post-surgery, than those in the non-MCI group (16.5% vs. 6.7%, p = 0.008; 27.1% vs. 15.8%, p = 0.024; and 18.8% vs. 8.2%, p < 0.001, respectively). Among them, 10.3% were assessed for POCD on postoperative day 7 and self-reported poor social roles and physical functioning 1 week postoperatively.

Conclusion

Preoperative MCI was seen in ~20% of surgical patients aged >70 years. POCD was seen in ~20% of patients with pre-existing MCI, and ~ 10% of those without. Benzodiazepine use, significant comorbidities, pre-existing MCI, and depressive tendencies were risk factors for POCD.

Preoperative frailty assessment combined with prehabilitation and nutrition strategies: Emerging concepts and clinical outcomes

Important elements of the preoperative assessment that should be addressed for the older adult population include frailty, comorbidities, nutritional status, cognition, and medications. Frailty has emerged as a plausible predictor of adverse outcomes after surgery. It is present in older patients and is characterized by multisystem physiologic decline, increased vulnerability to stressors, and adverse clinical outcomes. Preoperative preparation may include a prehabilitation program, which aims to address nutritional insufficiencies, modify chronic polypharmacy, and enhance physical and respiratory conditions prior to hospital admission. Special considerations are taken for particularly high-risk patients, where the approach to prehabilitation can address specific, individual risk factors. Identifying patients who are nutritionally deficient allows practitioners to intervene preoperatively to optimize their nutritional status, and different strategies are available, such as immunonutrition. Previous studies have shown an association between increased frailty and the risk of postoperative complications, morbidity, hospital length of stay, and 30-day and long-term mortality following general surgical procedures. Evidence from numerous studies suggests a potential benefit of including a standard assessment of frailty as part of the preoperative workup of older adult patients. Studies addressing validated frailty assessments and the quantification of their predictive capabilities in various surgeries are warranted.