The Role of Perioperative Statin Use in the Prevention of Delirium After Total Knee Replacement Under Spinal Anesthesia

Statin use in total joint arthroplasty: a systematic review

Introduction

There has been increased interest in the use of Statins in total hip and knee arthroplasty (THA and TKA) patients to improve outcomes and reduce postoperative complications. This study was performed to systematically review the evidence on Statin use in total joint arthroplasty, specifically its benefits and complications.

Methods

Adhering to the PRISMA guidelines, a systematic review of PubMed, Embase, Scopus, Web of Science, and the Cochrane database was performed to find studies reporting on the effects of Statin use on outcomes of THA and TKA. Two authors independently selected relevant papers to include.

Results

A total of 18 papers were included in the final analysis. Most were retrospective studies, with heterogeneous patient selection and outcome measures. The evidence on the risks and benefits of Statin use on outcomes of total joint arthroplasty was very limited and heterogeneous. Studies were focusing on perioperative cardiac outcomes, clinical outcomes and complications, renal, pulmonary, and gastrointestinal outcomes. Due to the heterogeneity of reported data, a formal meta-analysis was not possible.

Conclusions

There is some evidence in the literature suggesting that perioperative use of Statins, especially in Statin-naïve patients, may reduce cardiac (e.g. atrial fibrillation) and noncardiac (e.g. delirium) complications, while not increasing the risk of muscle or liver toxicity. The authors also found low levels of evidence that Statin use may reduce the long-term risk for revision surgery and osteolysis.

Preoperative Risk Factors Associated with Increased Incidence of Postoperative Delirium: Systematic Review of Qualified Clinical Studies

Postoperative delirium (POD) is an acute alteration of mental state, characterized by reduced awareness and attention, occurring up to five postoperative days after recovery from anesthesia. Several original studies and reviews have identified possible perioperative POD risk factors; however, there is no comprehensive review of the preoperative risk factors in patients diagnosed with POD using only validated diagnostic scales. The aim of this systematic review was to report the preoperative risk factors associated with an increased incidence of POD in patients undergoing non-cardiac and non-brain surgery. The reviewed studies included original research papers that used at least one validated diagnostic scale to identify POD occurrence for more than 24 h. A total of 6475 references were retrieved from the database search, with only 260 of them being suitable for further review. Out of the 260 reviewed studies, only 165 that used a validated POD scale reported one or more preoperative risk factors. Forty-one risk factors were identified, with various levels of statistical significance. The extracted risk factors could serve as a preoperative POD risk assessment workup. Future studies dedicated to the further evaluation of the specific preoperative risk factors' contributions to POD could help with the development of a weighted screening tool.

Statin Use and Delirium Risk: An Updated Systematic Review and Meta-Analysis

BACKGROUND

Findings on the association of statin use with delirium risk are inconsistent.

THE STUDY QUESTION

Is statin use associated with delirium risk?

STUDY DESIGN

We searched PubMed, the Cochrane Library, and the EMBASE database, limiting the search to human patients and articles in English published until December 31, 2021. The effect size and 95% confidence interval (CI) were defined as the odds ratio (OR) and 95% CI, respectively, to indicate the difference in the incidence of delirium between statin use and nonuse groups. A random-effects model was selected in the case of high heterogeneity of study populations. We used funnel plots, Egger test, Duval and Tweedie trim-and-fill approach, and the classic fail-safe N to assess publication bias.

RESULTS

Of a total of 264 identified studies, 13 were selected for the qualitative review-4 RCTs and 9 observational cohort studies. Statin use was not associated with low delirium risk (pooled OR, 0·82; 95% CI, 0·64-1·04; P = 0·09). Substantial statistical heterogeneity was observed (I2, 90%). Visual inspection of the funnel plot of ORs from the studies revealed symmetry. Using the Grading of Recommendations Assessment, Development, and Evaluation approach, we assigned the evidence a rating of C and a weak recommendation for this review.

CONCLUSIONS

Statin use is not associated with delirium risk. More comprehensive RCTs are required to confirm the results.

Effects of Atorvastatin Therapy on Postoperative Delirium After Malignant Tumor Surgeries in Older Adults

INTRODUCTION

Postoperative delirium (POD) is one of the prevalent and potentially fatal clinical conditions, leading to high disability and mortality in older patients, as well as increased duration of hospital stay and more hospitalization expenses. There were no effective drugs in the clinical management of POD, and an absence of evidence-based medicine concerning the treatment of POD.

MATERIALS AND METHODS

The present study explored whether atorvastatin (Ato) can decrease the occurrence rate of POD. The present research included patients over the age of 60 who were hospitalized to critical care units (ICUs) following surgery for malignant tumors. Patients received Ato (40mg/day) or placebos utilizing a computer-based random sequencing (in a 1:1 ratio). The primary outcome measure was the occurrence of delirium within the first seven days following surgery.

RESULTS

A total of 230 individuals were classified into two groups, namely the placebo group (n=123) and the Ato group (n=107). Patients belonging to two groups had similar baseline clinical data, and there were no statistically significant differences between them. The occurrence of delirium in the Ato group was remarkably reduced unlike the case in the placebo group. 30-day all-cause mortality did not vary significantly between the two groups. Pulmonary infection and Bedsore were significantly decreased in the Ato group than the placebo group, there were no statistically significant differences between the two groups in rhabdomyolysis and abnormal liver enzymes. In terms of medication responses, there were no statistically significant differences between the two groups. Ato patients had remarkably shortened hospital stays and spent remarkably less on hospitalization expenditures in comparison with those in the placebo group.

CONCLUSION

The findings from the present research indicated that Ato can decrease the occurrence of delirium following surgical operation of malignant tumors among elderly patients, it also can reduce the duration of hospitalization, hospital cost, and post-surgical complications, but not improve 30-day all-cause mortality.

REGISTRATION NUMBER

ChiCTR-IPR-17011984.

Effects of perioperative rosuvastatin on postoperative delirium in elderly patients: A randomized, double-blind, and placebo-controlled trial

BACKGROUND

Experimental evidence has indicated the benefits of statins for the treatment of postoperative delirium. Previously, clinical trials did not reach definite conclusions on the effects of statins on delirium. Some clinical trials have indicated that statins reduce postoperative delirium and improve outcomes, while some studies have reported negative results.

AIM

To evaluate whether perioperative rosuvastatin treatment reduces the incidence of delirium and improves clinical outcomes.

METHODS

This randomized, double-blind, and placebo-controlled trial was conducted in a single center in Jiangsu, China. This study enrolled patients aged greater than 60 years who received general anesthesia during elective operations and provided informed consent. A computer-generated randomization sequence (in a 1:1 ratio) was used to randomly assign patients to receive either rosuvastatin (40 mg/d) or placebo. Participants, care providers, and investigators were all masked to group assignments. The primary endpoint was the incidence of delirium, which was assessed twice daily with the Confusion Assessment Method during the first 7 postoperative days. Analyses were performed on intention-to-treat and safety populations.

RESULTS

Between January 1, 2017 and January 1, 2020, 3512 patients were assessed. A total of 821 patients were randomly assigned to receive either placebo (n = 411) or rosuvastatin (n = 410). The incidence of postoperative delirium was significantly lower in the rosuvastatin group [23 (5.6%) of 410 patients] than in the placebo group {42 (13.5%) of 411 patients [odds ratios (OR) = 0.522, 95% confidence interval (CI): 0.308-0.885; P < 0.05]}. No significant difference in 30-d all-cause mortality (6.1% vs 8.7%, OR = 0.67, 95%CI: 0.39-1.2, P = 0.147) was observed between the two groups. Rosuvastatin decreased the hospitalization time (13.8 ± 2.5 vs 14.2 ± 2.8, P = 0.03) and hospitalization expenses (9.3 ± 2.5 vs 9.8 ± 2.9, P = 0.007). No significant differences in abnormal liver enzymes (9.0% vs 7.1%, OR = 1.307, 95%CI: 0.787-2.169, P = 0.30) or rhabdomyolysis (0.73% vs 0.24%, OR = 3.020, 95%CI: 0.31-29.2, P = 0.37) were observed between the two groups.

CONCLUSION

The current study suggests that perioperative rosuvastatin treatment reduces the incidence of delirium after an elective operation under general anesthesia. However, the evidence does not reveal that rosuvastatin improves clinical outcomes. The therapy is safe. Further investigation is necessary to fully understand the potential usefulness of rosuvastatin in elderly patients.

Risk factors of postoperative delirium in the knee and hip replacement patients: a systematic review and meta-analysis

BACKGROUND

The risk factors of postoperative delirium (POD), a serious while preventable complication, developed by patients undergoing knee and replacement surgery are still under investigation. In this systematic review and meta-analysis, we identified risk factors associated with POD in knee and hip replacement.

METHODS

PubMed, Ovid MEDLINE, and Ovid EMBASE were used to identify original researches. The studies evaluating the risk factors of POD after knee and hip replacement were reviewed, and the qualities of the included studies were assessed with Newcastle-Ottawa Scale. Data were extracted, pooled, and a meta-analysis was completed RESULT: Twenty-two studies were finally included with a total of 11934 patients who underwent knee or hip replacement and 1841 developed POD with an incidence of 17.6% (95% confidential interval (CI) 13.2-22.0%). Eighteen significant risk factors were identified including advanced age (odds ratio (OR) 1.15 95% CI 1.08-1.22), cognitive impairment (OR 6.84, 95% CI 3.27-14.33), history of cerebrovascular events (OR 2.51, 95% CI 1.28-4.91), knee replacement (OR 1.42, 95% CI 1.00-2.02), blood loss (standardized mean difference (SMD) 0.30, 95% CI 0.15-0.44), dementia (OR 3.09, 95% CI 2.10-4.56), neurologic disorders (OR 2.26, 95% CI 1.23-4.15), psychiatric illness (OR 2.74, 95% CI 1.34-5.62), and obstructive sleep apnea (OR 4.17, 95% CI 1.72-10.09) along with several comorbidity evaluation scores and laboratory markers.

CONCLUSION

We identified risk factors consistently associated with the incidence of POD in knee and hip replacement. Strategies and interventions should be implemented to the patients receiving knee or hip replacement with potential risk factors identified in this meta-analysis.

The Effects of Propofol or Dexmedetomidine Sedation on Postoperative Recovery in Elderly Patients Receiving Lower Limb Surgery under Spinal Anesthesia: A Retrospective Propensity Score-Matched Analysis

Propofol and dexmedetomidine are the two most popular intravenous sedatives during anesthesia. However, data comparing the effects of these two sedatives during spinal anesthesia on postoperative recovery are still insufficient. We retrospectively analyzed the medical records of patients aged ≥65 years who underwent orthopedic surgery under spinal anesthesia between March 2012 and February 2017. The patients were allocated into two groups according to the intraoperative sedatives: the propofol group and dexmedetomidine group. We analyzed the incidence of postoperative delirium, analgesic requirement, and rescue anti-emetic treatment. A total of 1045 patients were included in the analysis. After propensity score matching with the propofol group, the dexmedetomidine group showed a lower incidence of postoperative delirium (odds ratio, 0.19; 95% CI, 0.07–0.56; p = 0.011). Postoperative analgesic and anti-emetic requirement were not significantly different between the two groups (p = 0.156 and 0.245, respectively). Multivariate logistic regression analysis revealed that intraoperative sedation, age, preoperative albumin level, and hip surgery were significantly associated with the incidence of postoperative delirium. This study showed that intraoperative dexmedetomidine sedation under spinal anesthesia during lower limb surgery is associated with a lower incidence of postoperative delirium compared with propofol sedation.