Postoperative cognitive dysfunction after sevoflurane or propofol general anaesthesia in combination with spinal anaesthesia for hip arthroplasty

Postoperative cognitive dysfunction: Review of pathophysiology, diagnostics and preventive strategies

Postoperative cognitive impairment is a common disorder after major surgery. Advances in medicine and treatment have resulted in an increasingly ageing population undergoing major surgical procedures. Since age is the most important risk factor for postoperative cognitive decline, it is not surprising that impairment of cognitive functions after surgery was recorded in almost a third of elderly patients. Postoperative cognitive dysfunction is part of the spectrum of postoperative cognitive impairment and researchers often confuse it with postoperative delirium and delayed neurocognitive recovery. This is the cause of great differences in the results of research that is focused on the incidence and possible prevention of postoperative cognitive dysfunction. In this review, we focused on current recommendations for a uniform nomenclature of postoperative cognitive impairment and diagnosis of postoperative cognitive dysfunction, the presumed pathophysiology of postoperative cognitive dysfunction and recommendations for its treatment and possible prevention strategies.

Anesthesia, Anesthetics, and Postoperative Cognitive Dysfunction in Elderly Patients

Postoperative cognitive dysfunction (POCD) remains a major issue that worsens the prognosis of elderly surgery patients. This article reviews the current research on the effect of different anesthesia methods and commonly utilized anesthetics on the incidence of POCD in elderly patients, aiming to provide an understanding of the underlying mechanisms contributing to this condition and facilitate the development of more reasonable anesthesia protocols, ultimately reducing the incidence of POCD in elderly surgery patients.

Long-term cognitive outcomes after surgery and anesthesia: what we find depends on where we look

Purpose of review

To review how anecdote and narrative medicine, primary cohort studies, epidemiological studies, and the dementia literature can be bridged to understand long-term postoperative cognitive decline.

Recent findings

Primary cohort studies have measured recoverable declines in memory and executive function after major surgery, but less-appreciated sources also offer critical insights. Anecdote reveals that functionally-impactful cognitive decline may persist after physical recovery in some patients despite modern medications and monitoring, and that physicians are unprepared to address patients' cognitive concerns. However, epidemiological studies reproducibly demonstrate that elective surgery has no, or a negligible, average impact on cognition in older patients. Cognitively provocative factors - like medical hospital admissions or health factors like diabetes and smoking - are common in late life, and surgery likely contributes minimally to long-term cognitive change for most patients.

Summary

Patients should be reassured that, while anecdotes of durable cognitive change after surgery are easily accessible, most patients experience cognitive recovery after major surgery. However, those who do not recover deserve characterization of their symptoms and investigation of modifiable causes to facilitate cognitive recovery.

Postoperative cognitive dysfunction-current research progress

Postoperative cognitive dysfunction (POCD) commonly occurs after surgery, particularly in elderly individuals. It is characterized by a notable decline in cognitive performance, encompassing memory, attention, coordination, orientation, verbal fluency, and executive function. This reduction in cognitive abilities contributes to extended hospital stays and heightened mortality. The prevalence of POCD can reach 40% within 1 week following cardiovascular surgery and remains as high as 17% 3 months post-surgery. Furthermore, POCD exacerbates the long-term risk of Alzheimer's disease (AD). As a result, numerous studies have been conducted to investigate the molecular mechanisms underlying POCD and potential preventive strategies. This article provides a review of the research progress on POCD.

Effects of anterior approach to quadratus lumborum block on postoperative cognitive function following hip surgery in older people: a randomized controlled clinical trial

BACKGROUND

Peripheral nerve block, including the quadratus lumborum block (QLB), has been used for postoperative analgesia in hip surgery. However, the effects of QLB on cognitive function after hip surgery remain unknown. This study aimed to assess the effects of the anterior approach to QLB on postoperative cognitive function in older people undergoing hip surgery.

METHODS

Sixty older people who underwent hip surgery from May 2021 to May 2022 were randomly divided into the QLB (n = 30) and control groups (n = 30). The Montreal Cognitive Assessment (MoCA) score (mean ± SD) was measured one day preoperatively and seven and 30 days postoperatively. The frequency (%) of postoperative cognitive dysfunction (POCD) was examined seven and 30 days postoperatively. The visual analog scale (VAS) scores at rest and Bruggrmann comfort scale (BCS) scores [Median (IQR)] 6 h (t1), 12 h (t2), 24 h (t3), and 48 h (t4) after surgery were assessed. The plasma high mobility group box protein 1 (HMGB1) and levels of interleukin-6 (IL-6) (mean ± SD) were evaluated 1 h preoperatively (baseline) and 24 h postoperatively (day 1). The requirement for rescue analgesia [Median (IQR)], time to first off-bed activity (mean ± SD), and adverse effects after surgery were also recorded.

RESULTS

Compared with the control group, the frequency of POCD was significantly lower in the QLB group seven days postoperatively (10.7% vs. 34.5%, P = 0.033), but no difference at 30 days postoperatively (3.6% vs. 10.3%, P = 0.319). There was no significant difference in MoCA scores between the two groups at one day preoperatively and 30 days postoperatively. However, the MoCA scores at seven days postoperatively were higher in the QLB group than in the control group (27.4 ± 1.81 vs. 26.4 ± 1.83, P = 0.043). In the QLB group, the VAS scores at t1, t2, and t3 were lower [3(2-4) vs. 4(3-4), P = 0.028; 3(2-3) vs. 4(3-5), P = 0.009; 2(1-3) vs. 2(2-3), P = 0.025], and the BCS scores at t1, t2, and t3 were higher than those in the control group [3(1-3) vs. 1(1-2), P = 0.006; 3(2-3) vs. 2(1-3), P = 0.011; 3(2-4) vs. 2(2-3), P = 0.041]. The patients in the QLB group reported significantly fewer requirements for rescue analgesia [0(0-1) vs. 1(0-2), P = 0.014]. The plasma levels of HMGB1 and IL-6 at 24 h postoperatively in the QLB group were significantly lower than in the control group (749.0 ± 185.7 vs. 842.1 ± 157.9, P = 0.046; 24.8 ± 8.1 vs. 31.9 ± 5.5, P < 0.001). The time to first off-bed activity from the end of surgery was shorter in the QLB group (25.3 ± 5.3 vs. 29.7 ± 6.9, P = 0.009). There was no significant difference in the incidence of postoperative complications between the two groups.

CONCLUSIONS

Anterior QLB given to older people undergoing hip surgery could promote early postoperative cognitive function recovery, provide adequate postoperative analgesia, and inhibit the release of inflammatory factors.

TRIAL REGISTRATION

Chictr.org.cn identifier ChiCTR2000040724 (Date of registry: 08/12/2020, prospectively registered).

Effects of xenon anesthesia on postoperative neurocognitive disorders: a systematic review and meta-analysis

The latest clinical trials have reported conflicting outcomes regarding the effectiveness of xenon anesthesia in preventing postoperative neurocognitive dysfunction; thus, this study assessed the existing evidence. We searched the PubMed, Embase, Cochrane Library, and Web of Science databases from inception to April 9, 2023, for randomized controlled trials of xenon anesthesia in postoperative patients. We included English-language randomized controlled studies of adult patients undergoing surgery with xenon anesthesia that compared its effects to those of other anesthetics. Duplicate studies, pediatric studies, and ongoing clinical trials were excluded. Nine studies with 754 participants were identified. A forest plot revealed that the incidence of postoperative neurocognitive dysfunction did not differ between the xenon anesthesia and control groups (P = 0.43). Additionally, xenon anesthesia significantly shortened the emergence time for time to opening eyes (P < 0.001), time to extubation (P < 0.001), time to react on demand (P = 0.01), and time to time and spatial orientation (P = 0.04). However, the Aldrete score significantly increased with xenon anesthesia (P = 0.005). Postoperative complications did not differ between the anesthesia groups. Egger's test for bias showed no small-study effect, and a trim-and-fill analysis showed no apparent publication bias. In conclusion, xenon anesthesia probably did not affect the occurrence of postoperative neurocognitive dysfunction. However, xenon anesthesia may effectively shorten the emergence time of certain parameters without adverse effects.

Chrysin Attenuates Oxidative Stress to Alleviate Sevoflurane-Induced Cognitive Impairments in Aged Rats

OBJECTIVE

Anesthesia-induced cognitive impairments are common for elder patients after surgery. Oxidative stress is the predominant factor contributing to the impairments. This study was to assess the therapeutic potential of an anti-oxidative naturally occurring flavonoid, chrysin, in attenuating sevoflurane-induced cognitive impairments in rat models.

METHODS

Rat models of cognitive impairments were constructed by exposing aged rats (18 months old) to sevoflurane for 2 h. Chrysin was administered via oral gavage at the dose of 25, 50, and 100 mg/kg/day for seven days. The elevated plus maze test was used to assess anxiety and explorative behaviors. Spatial memory tests were performed using novel object recognition test, object location memory task, and water maze experiments. Oxidative stress was evaluated by measuring levels of malondialdehyde, nicotinamide adenine dinucleotide phosphate, 4-hydroxynonenal, and glutathione using colorimetric assays. Quantitative real-time polymerase chain reaction and Western blot were used to analyze how chrysin affects nuclear factor E2-related factor (Nrf) signaling.

RESULTS

While sevoflurane anesthesia led to significant decline in cognitive performance in object recognition test, object location memory task, and water maze test, chrysin exerted significant effects in alleviating the impairments. Oxidative stress was also reduced in the hippocampus tissue of rats after chrysin intake. Nrf signaling was activated by chrysin treatment in sevoflurane-induced cognitive impairment models.

CONCLUSION

Chrysin was effective in alleviating cognitive impairments induced by sevoflurane anesthesia, which was at least in part facilitated by its effects in reducing oxidative stress via activating Nrf signaling.

Exogenous recombinant Hsp70 attenuates sevoflurane anesthesia-induced cognitive dysfunction in aged mice

BACKGROUND

Postoperative cognitive dysfunction (POCD) is a severe postoperative neurological sequela in elderly patients, and there is currently no standard treatment for POCD. In this study, whether recombinant human heat shock protein 70 (rHsp70) could alleviate sevoflurane-induced cognitive impairment in aged mice is investigated.

METHODS

To determine the prophylactic effect of rHsp70 in sevoflurane-induced cognitive dysfunction, aged mice were pretreated with different concentrations of rHsp70 (29.4, 58.8, and 117.6 μg/kg; intranasal injected; N = 12) every day for 1 week; then, 3% sevoflurane was utilized to anesthetize the aged mice. Cognitive function, neurotoxicity, and serum and hippocampal Hsp70 levels in aged mice undergoing sevoflurane anesthesia were assessed by the Morris water maze test and enzyme-linked immunosorbent assay. The effects of rHsp70 on inflammatory response were assessed by proinflammatory cytokine production and nuclear factor-κB (NF-κB) activation assays.

RESULTS

We found that aged mice exposed to sevoflurane showed reduced learning and memory ability and reduced Hsp70 expression, which were both restored by rHsp70 pretreatment. RHsp70 also reversed sevoflurane-induced up-regulated Bax and Bcl-2 expression and interleukin-1, IL-6, and monocyte chemoattractant protein-1 overproduction. Finally, rHsp70 pretreatment suppressed sevoflurane-induced NF-κB activation. Our study indicated that rHsp70 was sufficient to suppress sevoflurane-induced cognitive decline and neurotoxicity.

CONCLUSION

Our important finding warrants further study on the clinical application of rHsp70 in elderly patients undergoing anesthesia.

Perioperative stroke: A perspective on challenges and opportunities for experimental treatment and diagnostic strategies

Perioperative stroke is an ischemic or hemorrhagic cerebral event during or up to 30 days after surgery. It is a feared condition due to a relatively high incidence, difficulties in timely detection, and unfavorable outcome compared to spontaneously occurring stroke. Recent preclinical data suggest that specific pathophysiological mechanisms such as aggravated neuroinflammation contribute to the detrimental impact of perioperative stroke. Conventional treatment options are limited in the perioperative setting due to difficult diagnosis and medications affecting coagulation in may cases. On the contrary, the chance to anticipate cerebrovascular events at the time of surgery may pave the way for prevention strategies. This review provides an overview on perioperative stroke incidence, related problems, and underlying pathophysiological mechanisms. Based on this analysis, we assess experimental stroke treatments including neuroprotective approaches, cell therapies, and conditioning medicine strategies regarding their potential use in perioperative stroke. Interestingly, the specific aspects of perioperative stroke might enable a more effective application of experimental treatment strategies such as classical neuroprotection whereas others including cell therapies may be of limited use. We also discuss experimental diagnostic options for perioperative stroke augmenting classical clinical and imaging stroke diagnosis. While some experimental stroke treatments may have specific advantages in perioperative stroke, the paucity of established guidelines or multicenter clinical research initiatives currently limits their thorough investigation.

Restoration Algorithm-Based Ultrasound Image in Evaluating the Effect of Dexmedetomidine on Patients with Neurological Disorder Anesthetized by Sevoflurane

The study focused on the application value of ultrasound images processed by restoration algorithm in evaluating the effect of dexmedetomidine in preventing neurological disorder in patients undergoing sevoflurane anesthesia. 90 patients undergoing tonsillectomy anesthesia were randomly divided into normal saline group, propofol group, and dexmedetomidine group. The ultrasound images were processed by restoration algorithm, and during the postoperative recovery period, ultrasound images were used to evaluate. The results showed that the original ultrasonic image was fuzzy and contained interference noise, and that the image optimized by restoration algorithm was clear, without excess noise, and the image quality was significantly improved. In the dexmedetomidine group, the extubation time was 10.6 ± 2.3 minutes, the recovery time was 8.4 ± 2.2 minutes, the average pain score during the recovery period was 2.6 ± 0.7, and the average agitation score was 7.2 ± 2.4. Of 30 patients, there were 13 cases with vertigo and 1 case with nausea and vomiting. The vascular ultrasound imaging showed that, in the dexmedetomidine group, the peak systolic velocities (PSV) of the bilateral vertebral arteries during the recovery period were 67.7 ± 14.3 and 67.9 ± 15.2 cm/s, respectively; the end-diastolic velocities (EDV) of the bilateral vertebral arteries were 27.8 ± 6.7 and 24.69 ± 5.9 cm/s, respectively; the PSV in bilateral internal carotid artery systolic peak velocities were 67.2 ± 13.9 and 67.8 ± 12.7 cm/s, respectively; the EDV in bilateral internal carotid arteries were 27.7 ± 5.3 and 26.9 ± 4.9 cm/s, respectively; bilateral vertebral artery resistance indexes (RIs) were 0.6 ± 0.02 and 0.71 ± 0.08, respectively; the bilateral internal carotid artery RIs were 0.57 ± 0.04 and 0.58 ± 0.06, respectively, all better than the normal saline group (12.1 ± 2.5 minutes, 10.1 ± 2.3 minutes, 3.9 ± 0.6, 10.6 ± 3.7, 15 cases, 11 cases, 81.5 ± 13.6, 80.7 ± 11.6 cm/s, 29.3 ± 6.8, 28.9 ± 6.7 cm/s, 74.3 ± 10.2, 73.9 ± 12.5 cm/s, 29.1 ± 4.3, 29 ± 4.5 cm/s, 0.84 ± 0.06, 0.83 ± 0.05, 0.8 ± 0.04, and 0.81 ± 0.05) and the propofol group (11.4 ± 2.1 minutes, 9.0 ± 2.1 minutes, 3.4 ± 0.8, 8.5 ± 2.3, 12 cases, 9 cases, 72.5 ± 12.9, 73.4 ± 11.8 cm/s, 28.6 ± 5.4, 26.5 ± 5.1 cm/s, 72.1 ± 11.4, 73.5 ± 10.6 cm/s, 28.8 ± 5.6, 27.3 ± 4.7 cm/s, 0.78 ± 0.07, 0.82 ± 0.06, 0.76 ± 0.03, and 0.78 ± 0.05), and the differences were statistically significant (P < 0.05). In conclusion, ultrasound images processed by restoration algorithm have high image quality and high resolution. The dexmedetomidine can prevent neurological disorder in patients with sevoflurane anesthesia and is suggested in postoperative rehabilitation.

Postoperative Delirium and Postoperative Cognitive Dysfunction in Patients with Elective Hip or Knee Arthroplasty: A Narrative Review of the Literature

Postoperative delirium (POD) and postoperative cognitive dysfunction (POCD) are common complications following total knee arthroplasty (TKA) and total hip arthroplasty (THA), affecting the length of hospital stay and increasing medical complications. Although many papers have been published on both conditions in this setting, no reviews have currently been written. Thus, the purpose of our study is to summarize the current literature and provide information about POD and POCD following elective THA or TKA. Our literature search was conducted in the electronic databases PubMed and the Cochrane library. We found that POD is a common complication following elective THA or TKA, with a median incidence of 14.8%. Major risk factors include older age, cognitive impairment, dementia, preoperative (pre-op) comorbidities, substance abuse, and surgery for fracture. Diagnosis can be achieved using tools such as the confusion assessment method (CAM), which is sensitive, specific, reliable, and easy to use, for the identification of POD. Treatment consists of risk stratification and the implementation of a multiple component prevention protocol. POCD has a median incidence of 19.3% at 1 week, and 10% at 3 months. Risk factors include older age, high BMI, and cognitive impairment. Treatment consists of reversing risk factors and implementing protocols in order to preserve physiological stability. POD and POCD are common and preventable complications following TKA and THA. Risk stratification and specific interventions can lower the incidence of both syndromes. Every physician involved in the care of such patients should be informed on every aspect of these conditions in order to provide the best care for their patients.

Hypercholesterolemia aggravates sevoflurane-induced cognitive impairment in aged rats by inducing neurological inflammation and apoptosis

We aimed to explore the effects of hypercholesterolemia on sevoflurane-induced cognitive impairment in aged rats and the underlying mechanism(s). Aged rats were administrated with high-fat diet, sevoflurane, or both. Thereafter, the plasma levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) were evaluated. The Morris water maze task was performed to evaluate the spatial learning and memory ability of rats. Moreover, Nissl and Evans blue staining were conducted to test nerve damage and detect the blood-brain barrier permeability, respectively. The percentage of apoptotic cells was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. The messenger RNA expression of inflammatory factors and protein expression of microglial activation markers and apoptosis-related proteins were tested by real-time polymerase chain reaction, enzyme-linked immunosorbent assay, or western blot analysis, respectively. High-fat diet induced high levels of TC, TG, and LDL but decreased levels of HDL. However, sevoflurane had no effects on these levels. In contrast, sevoflurane significantly induced the impairment of learning and memory, nerve damage, neuroinflammatory damage, and neuronal apoptosis. Hypercholesterolemia exacerbated the sevoflurane-induced impairment in aged rats. These results suggested that hypercholesterolemia aggravates sevoflurane-induced cognitive impairment in aged rats, possibly by inducing neurological inflammation and apoptosis.

Neuroinflammation in perioperative neurocognitive disorders: From bench to the bedside

The perioperative neurocognitive disorders (PNDs) are one of the most common complications in elderly patients characterized by various forms of cognitive decline after anesthesia and surgery. Although the etiology for PNDs remained unclear, neuroinflammation has been characterized as one of the major causes, especially in the elderly patients. The activation of glial cells including microglia and astrocytes plays a significant role in the inflammatory responses in central nerve system (CNS). Although carefully designed, clinical studies on PNDs showed controversial results. Meanwhile, preclinical studies provided evidence from various levels, including behavior performance, protein levels, and gene expression. In this review, we summarize high‐quality studies and recent advances from both clinical and preclinical studies and provide a broad view from the onset of PNDs to its potential therapeutic targets. Future studies are needed to investigate the signaling pathways in PNDs for prevention and treatment, as well as the relationship of PNDs and future neurocognitive dysfunction.

Incidence of Postoperative Cognitive Dysfunction Following Inhalational vs Total Intravenous General Anesthesia: A Systematic Review and Meta-Analysis

Postoperative cognitive dysfunction (POCD) has been increasingly recognized as a contributor to postoperative complications. A consensus-working group recommended that POCD should be distinguished between delayed cognitive recovery, ie, evaluations up to 30 days postoperative, and neurocognitive disorder, ie, assessments performed between 30 days and 12 months after surgery. Additionally, the choice of the anesthetic, either inhalational or total intravenous anesthesia (TIVA) and its effect on the incidence of POCD, has become a focus of research. Our primary objective was to search the literature and conduct a meta-analysis to verify whether the choice of general anesthesia may impact the incidence of POCD in the first 30 days postoperatively. As a secondary objective, a systematic review of the literature was conducted to estimate the effects of the anesthetic on POCD between 30 days and 12 months postoperative. For the primary objective, an initial review of 1913 articles yielded ten studies with a total of 3390 individuals. For the secondary objective, four studies with a total of 480 patients were selected. In the first 30 days postoperative, the odds-ratio for POCD in TIVA group was 0.46 (95% CI = 0.26-0.81; p = 0.01), compared to the inhalational group. TIVA was associated with a lower incidence of POCD in the first 30 days postoperatively. Regarding the secondary objective, due to the small number of selected articles and its high heterogeneity, a metanalysis was not conducted. Given the heterogeneity of criteria for POCD, future prospective studies with more robust designs should be performed to fully address this question.

Fingolimod loaded niosomes attenuates sevoflurane induced cognitive impairments

Neurocognition is a severe, neurological challenge caused due to sevoflurane application for induction of anaesthesia. The plan of this study is to investigate the effect of fingolimod loaded niosomes on the cognitive impairment induced by sevoflurane. Span 40 and cholesterol were used in reverse phase evaporation techniques for the preparation of fingolimod -loaded niosomes. The positively charged niosomes were obtained by using chloride salts of 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP). The Fingolimod loaded niosomes has average particle size of 223.5 nm and the surface charge measured as + 8.7 ± 1.2 mV in presence of DOTAP. The Fingolimod loaded niosomes formulation shows higher entrapment efficiency. Fingolimod loaded positively charged niosomes were efficiently retained drug and increase the sustain release property. Fingolimod niosomes increases the spontaneous alternation in Y maze and reduces the escape latency in the Morris water maze test, which leads to significant (p < 0.01) improvement in spatial short-term and long-term memory. The neuronal death in the hippocampus due to the sevoflurane exposure was attenuated by fingolimod loaded niosomes, which was proved by histopathological study. It could be defined that fingolimod loaded niosomes attenuates the sevoflurane induced cognitive impairment.

Effects of inhalation and propofol anaesthesia on postoperative cognitive dysfunction in elderly noncardiac surgical patients: A systematic review and meta-analysis

BACKGROUND

Postoperative cognitive dysfunction (POCD) is a very common event in elderly noncardiac surgical patients. The effects of inhalational anaesthetics and propofol on the incidence of POCD and postoperative cognitive status at different time points after surgery are currently unclear.

METHODS

We searched the Embase, Medline, Cochrane Library, and Web of Science databases for randomized controlled trials (RCTs), in which inhalation anaesthesia and propofol anaesthesia were compared. The incidence of POCD or postoperative cognitive status was assessed in elderly patients undergoing noncardiac surgery.

RESULTS

Fifteen RCTs with 1854 patients were included in this meta-analysis. The incidence of POCD on postoperative Days 2-6 after propofol anaesthesia was markedly lower than that after inhalation anaesthesia (risk ratio (RR): 0.37, 95% confidence interval (CI): 0.15-0.88, P = .025), and Mini-Mental State Examination (MMSE) scores after propofol anaesthesia were substantially higher than those after inhalation anaesthesia (standard mean difference (SMD): 0.59, 95% CI: 0.07-1.11, P = .026). The levels of interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) were much lower after propofol anaesthesia than after inhalation anaesthesia (SMD: -2.027, 95% CI: -3.748- -0.307, P = .021; SMD: -0.68, 95% CI: -0.93- -0.43, P < .001).

CONCLUSIONS

The moderate evidence from this meta-analysis shows that, in elderly noncardiac surgical patients, propofol anaesthesia is superior to inhalation anaesthesia for attenuating of early POCD incidence, and low-level evidence shows that cognitive status is higher and systemic inflammation is less severe after propofol anaesthesia in the early days after surgery.

LIMITATIONS

The sample size was not sufficiently large for systemic inflammation, and the tools to identify POCD were not uniform in the included studies.

Does propofol ameliorate occurrence of postoperative cognitive dysfunction after general anaesthesia? A protocol of systematic review

BACKGROUND

Postoperative cognitive dysfunction (POCD) is a common condition after general anesthesia (GA). Previous studies have reported that propofol can ameliorate the occurrence of such disorder. However, its results are still inconsistent. Therefore, this systematic review will assess the efficacy and safety of propofol on POCD after GA.

METHODS

Literature sources will be sought from inception to the present in Cochrane Library, MEDLINE, EMBASE, PsycINFO, Web of Science, Scopus, Allied and Complementary Medicine Database, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure for randomized controlled trials (RCTs) assessing the administration of propofol on POCD after GA. All searches will be carried out without limitations to language and publication status. Outcomes comprise of cognitive impairments changes, impairments in short-term memory, concentration, language comprehension, social integration, quality of life, and adverse events. Cochrane risk of bias tool will be utilized to assess study quality. We will evaluate the quality of evidence for each outcome using Grading of Recommendations Assessment, Development and Evaluation approach. A narrative synthesis or a meta-analysis will be undertaken as appropriate.

DISCUSSION

This study will systematically and comprehensively search literature and integrate evidence on the efficacy and safety of propofol on POCD after GA. Our findings will be of interest to clinicians and health-related policy makers.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020164096.

Cognitive status of patients judged fit for discharge from the post-anaesthesia care unit after general anaesthesia: a randomized comparison between desflurane and propofol

Background

The Aldrete’s score is used to determine when a patient can safely leave the Post-Anaesthesia Care Unit (PACU) and be transferred to the surgical ward. The Aldrete score is based on the evaluation of vital signs and consciousness. Cognitive functions according to the anaesthetic strategy at the time the patient is judged fit for discharge from the PACU (Aldrete’s score ≥ 9) have not been previously studied. The aim of this trial was to assess the cognitive status of inpatients emerging either from desflurane or propofol anaesthesia, at the time of PACU discharge (Aldrete score ≥ 9).

Methods

Sixty adult patients scheduled for hip or knee arthroplasty under general anaesthesia were randomly allocated to receive either desflurane or propofol anaesthesia. Patients were evaluated the day before surgery using Digit Symbol Substitution Test (DSST), Stroop Color Test and Verbal Learning Test. After surgery, the Aldrete score was checked every 5 min until reaching a score ≥ 9. At this time, the same battery of cognitive tests was applied. Each test was evaluated separately. Cognitive status was reported using a combined Z score pooling together the results of all 3 cognitive tests.

Results

Among the 3 tests, only DSST was significantly reduced at Aldrete Score ≥ 9 in the Desflurane group. Combined Z-scores at Aldrete Score ≥ 9 were (in medians [interquartils]): − 0.2 [− 1.2;+ 0.6] and − 0.4 [− 1.1;+ 0.4] for desflurane and propofol groups respectively (P = 0.62). Cognitive dysfunction at Aldrete score ≥ 9 was observed in 3 patients in the Propofol group and in 2 patients in the Desflurane group) (P = 0.93).

Conclusion

No difference was observed in cognitive status at Aldrete score ≥ 9 between desflurane and propofol anaesthesia. Although approximately 10% of patients still had cognitive dysfunctions, an Aldrete score ≥ 9 was associated with satisfactory cognitive function recovery in the majority of the patients after lower limb arthroplasty surgery under general anaesthesia.

Trial registration

Clinical Trials identifier NTC02036736.

Prenatal sevoflurane exposure: Effects of iron metabolic dysfunction on offspring cognition and potential mechanism

For decades, the neurotoxicity caused by anesthetics in mammalian brain development has gained increasing attention. Exposure to anesthetics leads to neurotoxicity and apoptosis of nerve cells, which in turn induces cognitive dysfunction. Although most of the data came from animal studies, general anesthetics have been shown to have adverse effects on cognitive function in infants and young children in recent years. This concern has led to a number of retrospective studies that observed an association between general anesthesia in pregnant women and neurobehavioral problems in fetuses or offspring. Every year, many pregnant women undergo non-obstetric anesthesia due to various reasons such as traffic accidents, fetal interventions, acute appendicitis, symptomatic cholelithiasis, and trauma. A matter of concern for these pregnant women is whether anesthesia has a detrimental effect on fetal brain development in the womb and whether the fetus has cognitive impairment after birth. In humans, the association of anesthetic exposure in infants with the long-term impairment of neurologic functions has been reported in several retrospective clinical studies. Recently, we have found that sevoflurane anesthesia during pregnancy in mice-induced cognitive impairment in the offspring by causing iron deficiency and inhibiting myelinogenesis. Sevoflurane is a commonly used general anesthetic in the hospitals, which can induce neurotoxicity and cause cognitive impairment in fetuses, infants, children, and adults. However, the exact mechanism of sevoflurane-induced damage to the central nervous system (CNS) is not fully understood. Based on our recent results, this paper reviewed the effects of sevoflurane on cognitive impairment and pathological changes such as neurogenesis, neuronal apoptosis, and iron metabolism dysfunction in the offspring.

Diagnostic Criteria of Postoperative Cognitive Dysfunction: A Focused Systematic Review

Postoperative Cognitive Dysfunction (POCD) is characterized by a deterioration in cognitive performance after surgery and is increasingly addressed in research studies. However, a uniform definition of POCD seems to be lacking, which is a major threat to clinical research in this area. We performed a focused systematic review to determine the current degree of heterogeneity in how POCD is defined across studies and to identify those diagnostic criteria that are used most commonly. The search identified 173 records, of which 30 were included. Neurocognitive testing was most commonly performed shortly before surgery and at 7 days postoperatively. A variety of neurocognitive tests were used to test a range of cognitive domains, including complex attention, language, executive functioning, perceptual-motor function, and learning and memory. The tests that were used most commonly were the Mini-Mental State Examination, the digit span test, the trail making test part A, and the digit symbol substitution test, but consensus on which test result would be considered “positive” for POCD was sparse. The results of this systematic review suggest the lack of a consistent approach towards defining POCD. However, commonalities were identified which may serve as a common denominator for deriving consensus-based diagnostic guidelines for POCD.

Lithium chloride ameliorates cognition dysfunction induced by sevoflurane anesthesia in rats

Postoperative cognitive dysfunction is a common complication in elderly patients after surgeries involving anesthesia, but the underlying mechanisms are poorly understood. Lithium is a conventional treatment for bipolar disorder, which exerts a neuroprotective role in various diseases by inhibiting glycogen synthase kinase‐3β (GSK‐3β) in the brain and spinal cord. However, it is not known whether lithium chloride (LiCl) can protect against cognitive dysfunction induced by sevoflurane (SEV) anesthesia. Here, we examined the effects of LiCl on SEV‐induced cognitive dysfunction in rats and on SEV‐induced neuron apoptosis. We report that anesthesia with SEV significantly impaired memory performance, induced oxidative stress and hippocampal neuron apoptosis, and stimulated GSK‐3β activity. Treatment with LiCl ameliorated SEV‐induced cognitive disorder in rats by inhibiting the GSK‐3β/β‐catenin signaling pathway. In addition, LiCl reduced hippocampal neuron apoptosis and oxidative stress induced by SEV anesthesia. These results suggest that LiCl may have potential for development into a therapeutic agent for treatment of SEV anesthesia‐induced cognitive dysfunction.

Establishing a patient centered, outpatient total joint home recovery program within an integrated healthcare system

Outpatient total joint home recovery (HR) is a rapidly growing initiative being developed and employed at high volume orthopedic centers. Minimally invasive surgery, improved pain control and home health services have made HR possible. Multidisciplinary teams with members ranging from surgeons and anesthesiologists to hospital administrators, physical therapists, nurses and research analysts are necessary for success. Eligibility criteria for outpatient total joint arthroplasty will vary between medical centers. Surgeon preference in addition to medical comorbidities, social support, preoperative patient mobility and safety of the HR location are all factors to consider when selecting patients for outpatient total joint HR. As additional knowledge is gained, the next steps will be to establish 'best practices' and speciality society-endorsed guidelines for patients undergoing outpatient total joint arthroplasty.

Comparison of general anesthesia with endotracheal intubation, combined spinal-epidural anesthesia, and general anesthesia with laryngeal mask airway and nerve block for intertrochanteric fracture surgeries in elderly patients: a retrospective cohort study

BACKGROUND

There is no consensus on the optimal anesthesia method for intertrochanteric fracture surgeries in elderly patients. Our study aimed to compare the hemodynamics and perioperative outcomes of general anesthesia with endotracheal intubation, combined spinal-epidural anesthesia, and general anesthesia with laryngeal mask airway (LMA) and nerve block for intertrochanteric fracture surgeries in elderly patients.

METHODS

This is a retrospective study of 75 patients aged > 60 years scheduled for intertrochanteric fracture surgeries with general anesthesia with intubation (n = 25), combined spinal-epidural anesthesia (n = 25), and general anesthesia with LMA and nerve block (n = 25). The intraoperative hemodynamics were recorded, and the maximum variation rate was calculated. Postoperative analgesic effect was evaluated using the visual analog scale (VAS). Postoperative cognitive status was assessed using the Mini-Mental State Exam (MMSE).

RESULTS

The maximum variation rate of intraoperative heart rate, systolic blood pressure, diastolic blood pressure differed significantly between the three groups (general anesthesia with intubation > combined spinal-epidural anesthesia > general anesthesia with LMA and nerve block). The VAS scores postoperative 2 h, 4 h, 6 h, and 8 h also differed significantly between the three groups (general anesthesia with intubation > combined spinal-epidural anesthesia > general anesthesia with LMA and nerve block). The VAS scores postoperative 24 h were significantly lower in the general anesthesia with LMA/nerve block group than the general anesthesia with intubation group and the combined spinal-epidural anesthesia group. The MMSE scores postoperative 15 min and 45 min differed significantly between the three groups (general anesthesia with intubation < combined spinal-epidural anesthesia < general anesthesia with LMA and nerve block). The MMSE scores postoperative 120 min in the general anesthesia with intubation group were the lowest among the three groups. There was no significant difference in the incidence of respiratory infection postoperative 24 h, 48 h, and 72 h between the three groups.

CONCLUSION

Compared to general anesthesia with intubation and combined spinal-epidural anesthesia, general anesthesia with LMA and nerve block had better postoperative analgesic effect and less disturbances on intraoperative hemodynamics and postoperative cognition for elderly patients undergoing intertrochanteric fracture surgeries.

Acupuncture for perioperative care of total hip arthroplasty: A systemic review of controlled trials and meta-analysis

INTRODUCTION

This protocol is intended to conduct a systematic review and meta-analysis to evaluate the efficacy and safety of acupuncture in perioperative care of total hip arthroplasty patients.

METHODS AND ANALYSIS

The following databases will be searched from their inception to November 2018 without language restrictions: MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, the Cumulative Index to Nursing and Allied Health Literature, Oriental Medicine Advanced Searching Integrated System, Korean Traditional Knowledge Portal, KoreaMed, DBPIA, Research Information Service System, including the China National Knowledge Infrastructure. Any randomized controlled trials related to perioperative care of total hip arthroplasty will be included. The primary outcomes of this study are dosage of analgesics and pain intensity. For secondary outcomes, Harris hip score, incidence of postoperative cognitive dysfunction, mini-mental state exam score, incidence of deep vein thrombosis, D-dimer and fibrinogen level, adverse events will be assessed. Data analysis and synthesis will be carried out using RevMan version 5.3. The methodological quality will be assessed by the Cochrane Collaboration risk of bias tool.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42018112123.