Anesthesia and Cognitive Outcome in Elderly Patients: A Narrative Viewpoint

A 74-Year-Old Man with Severe Comorbidities and Successful Abdominal Aortic Aneurysm Repair with Thoracic Segmental Spinal Anesthesia: A Case Report

BACKGROUND Elderly patients with severe or multiple comorbidities can be at high risk for complications of general anesthesia. This report is of a 74-year-old man with severe comorbidities, including ischemic heart disease (IHD) and chronic obstructive pulmonary disease (COPD), and successful abdominal aortic aneurysm repair with thoracic segmental spinal anesthesia. CASE REPORT The patient, aged 74, had previously been diagnosed with severe COPD and IHD. He was classified as American Society of Anesthesiology (ASA) grade IV, diagnosed with an abdominal aortic aneurysm (AAA) measuring 6 cm in diameter, and had to undergo surgical repair of the aneurysm with the insertion of a synthetic graft. Due to a shortage of beds in the ICU and the desire to avoid the complications associated with general anesthesia, the decision was made to proceed with thoracic spinal regional anesthesia, which is not a customary choice for this type of surgery. Spinal anesthesia was administered at the Th10-11 level, utilizing 8.5 mg of Bupivacaine, 50 mcg of Fentanyl, and 4 mg of Dexason. An epidural catheter was placed at the same level. The surgical procedure lasted 145 min and was successfully completed under regional anesthesia. CONCLUSIONS This report has highlighted that developments in spinal thoracic anesthesia mean that this can be a successful alternative to general anesthesia in high-risk patients, even for major emergency surgery.

Anesthesia and dementia: An up-to-date review of the existing literature

Concerns around the impact of anesthesia on cognitive decline and dementia, including Alzheimer's Disease (AD), have been increasing and recently attracting considerable attention in the research community. One unanswered question is whether anesthesia is a risk factor of dementia, specifically AD type dementia. A large body of evidence, coming from in vivo and in vitro models, suggests that exposure to anesthetic agents may increase the risk of AD through mechanisms of action similar to AD's neuropathology. In terms of clinical studies, our knowledge of the relationship between anesthesia and dementia is based on limited data, with most studies suggesting that there is no association. The aim of this paper was therefore to outline recent clinical studies exploring this controversial relationship and discuss future directions in terms of study design and potential areas of study. As the aging population and the prevalence of dementia and AD increases, we need a better understanding of anesthesia as a risk factor for neurodegeneration through well-designed studies. Despite the controversy, there seems to be little evidence to support that anesthesia itself or other surgical and patient factors can cause or accelerate AD.

Association between sedation during spinal anesthesia and mortality in older patients undergoing hip fracture surgery: A nationwide retrospective cohort study in Japan

STUDY OBJECTIVE

Intraoperative sedation plays an important role in the management of regional anesthesia. Few studies have investigated the association of sedation during spinal anesthesia with postoperative mortality in older patients as a primary outcome. This study aimed to test the hypothesis that sedation during spinal anesthesia increases postoperative mortality in older patients undergoing hip fracture surgery.

DESIGN

Retrospective, cohort study.

SETTING

Acute and subacute care hospitals in Japan.

PATIENTS

Patients aged 65 years and older who received hip fracture surgery under spinal anesthesia between April 2014 and May 2022.

EXPOSURE

Sedation during spinal anesthesia.

MEASUREMENTS

Postoperative in-hospital all-cause mortality within 30 days.

MAIN RESULTS

In total, 25,554 eligible patients were identified. Propensity score matching created 4735 pairs, and baseline patient characteristics were acceptably balanced between the sedation and non-sedation groups. There was no significant difference in 30-day postoperative mortality between the two groups (hazard ratio [95% CIs]: 0.92 [0.59-1.44]).

CONCLUSIONS

There was no association between sedation during hip fracture surgery in older patients under spinal anesthesia and postoperative mortality. However, these results are limited to our population, and further prospective studies are needed to determine the safety of sedation.

Influence of Different Sevoflurane Concentrations on Postoperative Cognitive Function in Aged Rats

BACKGROUND

Postoperative cognitive dysfunction may be associated with neuroinflammation, and sevoflurane suppresses surgery-induced inflammation. We hypothesized that low concentrations of sevoflurane would result in more impaired postoperative cognitive function compared to high concentrations.

METHODS

Aged male Sprague-Dawley rats (n = 21, 17-22 months) were randomly assigned to 1 of 3 groups: control (C), sevoflurane 2% (S2), and sevoflurane 4% (S4). Rats in the S2 and S4 groups underwent open femoral fracture and intramedullary fixation of the left hind limb under 2 hours of sevoflurane anesthesia. Neurological outcomes were evaluated using the Morris water maze (MWM) test, and histopathological outcomes were assessed 28 days after surgery.

RESULTS

The S2 group showed prolonged swimming latency compared to S4 on day 7 (difference of means, 34.4; 95% confidence interval [CI], 2.57-66.3; P = .031) and compared to the C group on day 9 (difference of means, -33.4; 95% CI, -65.3 to -1.55; P = .037). The intact CA1 cells in the S2 group were significantly less than those in the C and S4 groups (H statistic, 10.87; P = .006 versus C; P = .033 versus S4).

CONCLUSIONS

We found that low concentrations of sevoflurane prolonged the swimming latency of the MWM compared to high concentrations and reduced intact CA1 hippocampal neurons in aged rats. These results suggest that low-concentration sevoflurane anesthesia may be more detrimental than high concentration for spatial cognitive function and postoperative impairment of hippocampal CA1 cells in aged rats.

Cognitive function in older patients and their stress challenge using different anesthesia regimes: a single center observational study

BACKGROUND

With increasing age older patients are at higher risk for cognitive decline after surgery. Even tailored anesthesia procedures in older patients remain a high risk for postoperative cognitive disorder. Additional stress derived from anxiety and anesthesia itself can negatively impact postoperative cognitive outcomes. The objective of this study was to evaluate the impact of general versus regional anesthesia on postoperative cognitive disorder and indicators of perioperative stress in elderly undergoing surgery.

METHODS

In this single center prospective study between December 2014 and November 2015, 46 patients aged 50 to 85 years undergoing dermatology surgery were enrolled. Patients were stratified by receiving general versus regional nerve anesthesia. On three consecutive days, saliva cortisol levels were analyzed three times per day. Cognitive function was assessed on the day before and the day after surgery using comprehensive neuropsychological testing of multiple cognitive functions including memory, executive function, attention and processing speed.

RESULTS

Comparing the regional anesthesia group (RAG, n = 28) with the general anesthesia group (GAG, n = 18) no significant difference in the postoperative cognitive function was observed. However, patients in the GAG had significantly higher postoperative cortisol levels when compared to patients in the RAG. In both groups, a peak of cortisol value was detected on the day of surgery, which was higher in the GAG in comparison to the RAG.

CONCLUSIONS

We did not observe a difference in postoperative cognitive function between patients undergoing regional or general anesthesia for dermatology surgery. However, we found lower cortisol level in the RAG. Based on these findings, future studies should investigate alternatives to reduce stress in a general anesthesia setting.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT02505815.

Third-line therapy for overactive bladder in the elderly: Nuances and considerations

INTRODUCTION

Overactive bladder (OAB) disproportionally affects older adults in both incidence and severity. OAB pharmacotherapy is often problematic in the elderly due to polypharmacy, adverse side effect profiles and contraindications in the setting of multiple comorbidities, and concerns regarding the risk of incident dementia with anticholinergic use. The burden of OAB in older patients coupled with concerns surrounding pharmacotherapy options should motivate optimization of nonpharmacologic therapies in this population. At the same time, several aspects of aging may impact treatment efficacy and decision-making. This narrative review critically summarizes current evidence regarding third-line OAB therapy use in the elderly and discusses nuances and treatment considerations specific to the population.

METHODS

We performed an extensive, nonsystematic evidence assessment of available literature via PubMed on onabotulinumtoxinA (BTX-A), sacral neuromodulation, and percutaneous tibial nerve stimulation (PTNS) for OAB, with a focus on study in elderly and frail populations.

RESULTS

While limited, available studies show all three third-line therapies are efficacious in older populations and there is no data to support one option over another. BTX-A likely has a higher risk of urinary tract infection and retention in older compared to younger populations, especially in the frail elderly. PTNS incurs the lowest risk, although adherence is poor, largely due to logistical burdens.

CONCLUSION

Advanced age and frailty should not preclude third-line therapy for refractory OAB, as available data support their efficacy and safety in these populations. Ultimately, treatment choices should be individualized and involve shared decision-making.

Metformin alleviates prolonged isoflurane inhalation induced cognitive decline via reducing neuroinflammation in adult mice

With the widespread use of volatile anesthetic agents in the prolonged sedation for COVID-19 pneumonia and ARDS, there is an urgent need to investigate the effects and treatments of lengthy low-concentration inhaled anesthetics exposure on cognitive function in adults. Previous studies showed that general anesthetics dose- and exposure length-dependently induced neuroinflammatory response and cognitive decline in neonatal and aging animals. The anti-diabetes drug metformin has anti-neuroinflammation effects by modulating microglial polarization and inhibiting astrocyte activation. In this study, we demonstrated that the inhalation of 1.3% isoflurane (a sub-minimal alveolar concentration, sub-MAC) for 6 h impaired recognition of novel objects from Day 1 to Day3 in adult mice. Prolonged sub-MAC isoflurane exposure also triggered typically reactive microglia and A1-like astrocytes in the hippocampus of adult mice on Day 3 after anesthesia. In addition, prolonged isoflurane inhalation switched microglia into a proinflammatory M1 phenotype characterized by elevated CD68 and iNOS as well as decreased arginase-1 and IL-10. Metformin pretreatment before anesthesia enhanced cognitive performance in the novel object test. The positive cellular modifications promoted by metformin pretreatment included the inhibition of reactive microglia and A1-like astrocytes and the polarization of microglia into M2 phenotype in the hippocampus of adult mice. In conclusion, prolonged sub-MAC isoflurane exposure triggered significant hippocampal neuroinflammation and cognitive decline in adult mice which can be alleviated by metformin pretreatment via inhibiting reactive microglia and A1-like astrocytes and promoting microglia polarization toward anti-inflammatory phenotype in the hippocampus.

Anesthesia: Synaptic power failure

One of the greatest unresolved mysteries in medicine relates to the molecular and neuronal mechanisms through which general anesthetics abolish perception. A new study in mice with mutations affecting mitochondrial complex 1 suggests that anesthetic-disruption of cellular energetics impairs endocytosis to alter synaptic function.

Effects of biophilic virtual reality on cognitive function of patients undergoing laparoscopic surgery: study protocol for a sham randomised controlled trial

INTRODUCTION

Virtual reality (VR) is already being used for cognitive or emotional rehabilitation. However, its role in postoperative cognitive dysfunction (POCD) has not been fully recognised. Due to the lack of an effective postoperative follow-up system, the incidence of POCD in China is not clear, and although many drugs have been proposed to improve POCD in the animal study, their clinical applications are limited, while VR provides an innovative method to provide non-pharmacological management.

METHODS AND DESIGN

This is a single-centre, randomised, double-blind, sham-controlled clinical trial. In this study, 600 patients over 55 years old undergoing laparoscopic surgery will be recruited. Participants will be randomly assigned to receive biophilic VR or sham VR (1:1 ratio), all patients have 20 min of exposure per day during the hospital stay. The primary outcome is the impact of VR on the incidence of POCD. Secondary outcomes include perioperative anxiety and instrumental activities of daily living. Changes in the performance of the neurocognitive batteries are measured by a local resident doctor. Serum samples will be collected on the day before surgery and 7 days after surgery.

ETHICS AND DISSEMINATION

This trial has ethical approval from the Medical Ethics Committee of the Affiliated Hospital of Medical School of Ningbo University (KY20210302). The study is sponsored by Ningbo University and Ningbo Science and Technology Bureau.

CONTACT

Dr. Mao Haijiao, Chair of the hospital medical Ethics committee (ndfylunli@126.com). Trial results will be submitted for publication in peer-reviewed journals, patient recruitment began in April 2021. Written informed consent is obtained for all participants. All information acquired will be disseminated via national or international conferences and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ChiCTR2000040919.

A Comparison of Operative Time and Intraoperative Blood Volume Loss Between Stemless and Short‐stem Anatomic Total Shoulder Arthroplasty: A Single Institution's Experience

There has been increasing interest in the use of stemless humeral implants for total shoulder arthroplasty when compared with both short-stem (SS) and standard-length implants. Although evidence for decreased surgical time and blood loss exists for stemless versus standard-length stems, far less literature exists comparing these clinical parameters for stemless versus SS implants.

Cognitive Impairment Following Clinical or Recreational Use of Gammahydroxybutyric Acid (GHB): A Systematic Review

BACKGROUND

GHB (gamma-hydroxybutyric acid; sodium oxybate) is a general anaesthetic that is clinically used for the treatment of narcolepsy, cataplexy, alcohol withdrawal and alcohol relapse prevention. In addition, GHB is recreationally used. Most clinical and recreational users regard GHB as an innocent drug devoid of adverse effects, despite its high dependence potential and possible neurotoxic effects. At high doses, GHB may lead to a comatose state. This paper systematically reviews possible cognitive impairments due to clinical and recreational GHB use.

METHODS

PubMed and PsychINFO were searched for literature data about the acute and residual cognitive deficits following GHB use. This review is conducted using the PRISMA protocol.

RESULTS

A total of 43 reports covering human and animal data on GHB-induced cognitive impairments were eligible and reviewed. This systematic review found no indication for cognitive impairments after clinical GHB use. However, it supports the view that moderate GHB use may result in acute short-term cognitive impairments, whereas regular high-dose GHB use and/or multiple GHB-induced comas are probably neurotoxic resulting in long-term residual cognitive impairments.

CONCLUSION

These results emphasize the need for awareness among clinicians and recreational users to minimize negative health consequences of recreational GHB use, particularly when high doses are used and GHB-induced comas occur.

A randomized trial: bispectral-guided anesthesia decreases incidence of delayed neurocognitive recovery and postoperative neurocognitive disorder but not postoperative delirium

BACKGROUND

Postoperative cognitive dysfunction (POCD), also known as delayed neurocognitive recovery (up to 30 days) and postoperative neurocognitive disorder (up to 12 months), is a frequent complication of the neurological system associated with poor outcome. This randomized controlled trial aimed to determine whether bispectral (BIS) monitoring is correlated with delayed neurocognitive recovery, postoperative neurocognitive disorder, or postoperative delirium (POD).

METHODS

Among 197 patients included in the study, 100 were assigned to the BIS group and 97 to the control group. The BIS index was kept at 40-60 in the BIS group, and the depth of anesthesia in the control group was maintained according to anesthetists' clinical experience. Cognitive function was evaluated from the 1^st-7^th day after the operation and the time of discharge, and at 1^st month, 6^th months, and 1 year after the operation.

RESULTS

The incidence of delayed neurocognitive recovery (3% vs. 21.6%, P<0.001, at 7^th day) (3% vs. 21.1%, P<0.001, at 1^st month) and postoperative neurocognitive disorder (6.2% vs. 21.3%, P=0.002, at 6^th month) (4.4% vs. 16.3%, P=0.009, at 1 year) were lower in the BIS group, while there was no significant difference in POD between the two groups (12% vs. 19.6%, P=0.144). The average value of intraoperative BIS was lower in the BIS group (43.75 vs. 50.69, P<0.001). The postoperative hospitalization time (9.99 vs. 12.41, P<0.001) and the mortality (5.4% vs. 14.4%, P=0.042) were significantly decreased, while satisfaction was higher in the BIS group (39% vs. 24.7%, P=0.009).

CONCLUSION

BIS decreases delayed neurocognitive recovery and postoperative neurocognitive disorder; however, it is not associated with POD. BIS monitoring could effectively lessen postoperative hospitalization and mortality and increase patient satisfaction.

Connexin 43 gap junction-mediated astrocytic network reconstruction attenuates isoflurane-induced cognitive dysfunction in mice

Background

Postoperative cognitive dysfunction (POCD) is a common complication following anesthesia and surgery. General anesthetic isoflurane has potential neurotoxicity and induces cognitive impairments, but the exact mechanism remains unclear. Astrocytes form interconnected networks in the adult brain through gap junctions (GJs), which primarily comprise connexin 43 (Cx43), and play important roles in brain homeostasis and functions such as memory. However, the role of the GJ-Cx43-mediated astrocytic network in isoflurane-induced cognitive dysfunction has not been defined.

Methods

4-month-old male C57BL/6 mice were exposure to long-term isoflurane to induce cognitive impairment. To simulate an in vitro isoflurane-induced cognitive dysfunction‐like condition, primary mouse astrocytes were subjected to long-term isoflurane exposure. Cognitive function was assessed by Y-maze and fear conditioning tests. Western blot was used to determine the expression levels of different functional configurations of Cx43. The morphology of the GJs-Cx43 was evaluated by immunofluorescence staining. Levels of IL-1β and IL-6 were examined by ELISA. The ability of GJs-Cx43-mediated intercellular communication was examined by lucifer yellow dye transfer assay. Ethidium bromide uptake assays were used to measure the activity of Cx43 hemichannels. The ultrastructural morphology of astrocyte gap junctions and tripartite synapse were observed by transmission electron microscopy.

Results

After long-term isoflurane anesthesia, the GJs formed by Cx43 in the mouse hippocampus and primary mouse astrocytes were significantly reduced, GJs function was impaired, hemichannel activity was enhanced, the levels of IL-1β and IL-6 were increased, and mice showed significant cognitive impairment. After treatment with the novel GJ-Cx43 enhancer ZP1609, GJ-Cx43-mediated astrocytic network function was enhanced, neuroinflammation was alleviated, and ameliorated cognition dysfunction induced by long-term isoflurane exposure. However, ZP1609 enhances the astrocytic network by promoting Cx43 to form GJs without affecting hemichannel activity. Additionally, our data showed that long-term isoflurane exposure does not alter the structure of tripartite synapse.

Conclusion

Our results reveal a novel mechanism of the GJ-Cx43-mediated astrocytic network involved in isoflurane-induced neuroinflammation and cognitive impairments, which provides new mechanistic insight into the pathogenesis of POCD and identifies potential targets for its treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-022-02424-y.

Age-related differences in cognition and postoperative quality of recovery after beach chair position shoulder surgery

We examined the influence of age in beach chair position shoulder surgery and postoperative quality of recovery by conducting a single-site, observational, cohort study comparing younger aged (18-40 years) versus older aged (at least 60 years) patients admitted for elective shoulder surgery in the beach chair position. Endpoints were dichotomous return of function to each patient's individual preoperative baseline as assessed using the postoperative quality of recovery scale; measuring cognition, nociception, physiological, emotional, functional activities and overall perspective. We recruited 112 (41 younger and 71 older aged) patients. There was no statistical difference in cognitive recovery at day three postoperatively (primary outcome): 26/32 younger patients (81%) versus 43/60 (72%) older patients, P=0.45. Rates of recovery were age-dependent on domain and time frame (secondary outcomes), with older patients recovering faster in the nociceptive domain (P=0.02), slower in the emotional domain (P=0.02) and not different in the physiological, functional activities and overall perspective domains (all P >0.35). In conclusion, we did not show any statistically significant difference in cognitive outcomes between younger and older patients using our perioperative anaesthesia and analgesia management protocol. Irrespective of age, 70% of patients recovered by three months in all domains.

Electroencephalographic Burst-Suppression, Perioperative Neuroprotection, Postoperative Cognitive Function, and Mortality: A Focused Narrative Review of the Literature

Burst-suppression is an electroencephalographic pattern that results from a diverse array of pathophysiological causes and/or metabolic neuronal suppression secondary to the administration of anesthetic medications. The purpose of this review is to provide an overview of the physiological mechanisms that underlie the burst-suppression pattern and to present in a comprehensive way the available evidence both supporting and in opposition to the clinical use of this electroencephalographic pattern as a therapeutic measure in various perioperative settings.

Amelioration of Hippocampal Insulin Resistance Reduces Tau Hyperphosphorylation and Cognitive Decline Induced by Isoflurane in Mice

General anesthetics can induce cognitive impairments and increase the risk of Alzheimer’s disease (AD). However, the underlying mechanisms are still unknown. Our previous studies shown that long-term isoflurane exposure induced peripheral and central insulin resistance (IR) in adult mice and aggravated IR in type 2 diabetes mellitus (T2DM) mice. Clinical and preclinical studies revealed an association between impaired insulin signaling and tau pathology in AD and other tauopathies. We investigated if alleviation of hippocampal IR by the antidiabetic agent metformin could reduce tau hyperphosphorylation and cognitive decline induced by isoflurane in mice. The effects of prolonged (6 h) isoflurane anesthesia on hippocampal IR, hippocampal tau hyperphosphorylation, and hippocampus-dependent cognitive function were evaluated in wild type (WT) adult mice and the high-fat diet plus streptozotocin (HFD/STZ) mouse model of T2DM. Here we shown that isoflurane and HFD/STZ dramatically and synergistically induced hippocampal IR and fear memory impairment. Metformin pretreatment strongly ameliorated hippocampal IR and cognitive dysfunction caused by isoflurane in WT mice, but was less effective in T2DM mice. Isoflurane also induced hippocampal tau hyperphosphorylation and metformin reversed this effect. In addition, isoflurane significantly increased blood glucose levels in both adult and T2DM mice, and metformin reversed this effect as well. Administration of 25% glucose to metformin-pretreated mice induced hyperglycemia, but surprisingly did not reverse the benefits of metformin on hippocampal insulin signaling and fear memory following isoflurane anesthesia. Our findings show hippocampal IR and tau hyperphosphorylation contribute to acute isoflurane-induced cognitive dysfunction. Brief metformin treatment can mitigate these effects through a mechanism independent of glycemic control. Future studies are needed to investigate whether long-term metformin treatment can also prevent T2DM-induced hippocampal IR and cognitive decline.

Comparison of digital games as a cognitive function assessment tool for current standardized neuropsychological tests

Objective

Cognitive dysfunction may occur postoperatively. Fast and efficient assessment of Postoperative Cognitive Dysfunction (POCD) can minimize loss of quality of life, and therefore, a study comparing a digital game with standard neuropsychological tests to assess executive, mnemonic, and attention functions to evaluate POCD seems to be relevant both for research and clinical practice.

Methods

A battery of standardized tests and a digital game (MentalPlus®) were administered to 60 patients at the Central Institute of Hospital das Clínicas in São Paulo (36 women and 24 men), with ages between 29 and 82 years, pre- and post-surgery performed under anesthesia. Correlation and linear regression model were used to compare the scores obtained from the standardized tests to the scores of the six executive and cognitive functions evaluated by the game (short- and long-term memory, selective and alternating attention, inhibitory control, and visual perception).

Results

After correlation analysis, a statistically significant result was found mainly for the correlation between the scores from the phase of the digital game assessing the visuoperception function and the scores from the A and B cards of the Stroop Test (p < 0.001, r = 0.99 and r = 0.64, respectively), and the scores from TMTA (p = 0.0046, r = 0.51). We also found a moderate correlation between the phase of the game assessing short-memory function and VVLT (p < 0.001, r = 0.41). No statistically significant correlations were found for the other functions assessed.

Conclusion

The digital game provided scores in agreement with standardized tests for evaluating visual perception and possibly short-term memory cognitive functions. Further studies are necessary to verify the correlation of other phases of the digital game with standardized tests assessing cognitive functions.

Anesthesiology: Resetting Our Sights on Long-term Outcomes: The 2020 John W. Severinghaus Lecture on Translational Science

Anesthesiologists have worked relentlessly to improve intraoperative anesthesia care. They are now well positioned to expand their horizons and address many of the longer-term adverse consequences of anesthesia and surgery. Perioperative neurocognitive disorders, chronic postoperative pain, and opioid misuse are not inevitable adverse outcomes; rather, they are preventable and treatable conditions that deserve attention. The author's research team has investigated why patients experience new cognitive deficits after anesthesia and surgery. Their animal studies have shown that anesthetic drugs trigger overactivity of "memory-blocking receptors" that persists after the drugs are eliminated, and they have discovered new strategies to preserve brain function by repurposing available drugs and developing novel therapeutics that inhibit these receptors. Clinical trials are in progress to examine the cognitive outcomes of such strategies. This work is just one example of how anesthesiologists are advancing science with the goal of improving the lives of patients.

Effect of propofol-based total intravenous anaesthesia on postoperative cognitive function and sleep quality in elderly patients

PURPOSE

This study aimed to observe the effect of propofol-based total intravenous anaesthesia (TIVA) on postoperative cognitive function and sleep quality in elderly patients.

METHODS

From August 2019 to August 2020, 130 cases of elderly patients who underwent abdominal surgery in The Third Hospital of Hebei Medical University were enrolled in this study. All participants were randomly divided into TIVA group (n = 65, receiving propofol-based TIVA) and control group (n = 65, receiving inhaled of sevoflurane anaesthesia). Intra-operative indicators were recorded in both groups. The cognitive function, sleep quality, urine melatonin sulphate, free cortisol, S-100 β protein and interleukin-6 (IL-6) levels were compared at different times.

RESULTS

On 1, 3, 7 and 15 days after operation, the cognitive function of the TIVA group was better than that of the control group, with statistically significance (P < .05, respectively). On the day of surgery, the two groups had similar sleep quality. The sleep quality of the TIVA group was better than that of the control group on 1, 3 and 7 days after surgery (P < .05, respectively). On the day of surgery, the levels of melatonin, cortisol, S-100β protein and IL-6 in the two groups were equivalent (P > .05). On 1, 3, 7 and 15 days after surgery, cortisol and IL-6 in the TIVA group were lower than those of the control group, and melatonin was higher than that of the control group (P < .05, respectively). On 1, 3 and 7 days after operation, the S-100 β protein in the TIVA group was lower than that in the control group (P < .05, respectively).

CONCLUSION

Propofol-based TIVA has little effect on the cognitive function and sleep quality of elderly patients after surgery, and it is worthy of clinical application.

Comparison of arterial blood pressure and cardiac index-based hemodynamic management on cognitive function in elderly patients undergoing spinal surgery: a randomized clinical trial

BACKGROUND

Postoperative delayed neurocognitive recovery (DNR) is frequent in elderly patients. Prevention of DNR is essential to achieve a better postoperative outcome.

METHODS

The aim of the present study was to compare mean arterial pressure (MAP) and Cardiac Index (CI) based hemodynamic management on early cognitive function in elderly patients undergoing spinal surgery. Sixty patients aged ≥60 years were enrolled. Patients were randomized to one of two groups. In Group MAP, hemodynamic management of patients was performed according to the MAP value. In Group CI, hemodynamic management of patients was performed according to the CI value. In all patients, standard anesthesia method was used and regional cerebral oxygen saturation (rScO<inf>2</inf>) was measured. Cognitive functions of patients were assessed by Montreal cognitive assessment (MoCA) test before surgery and seven days after surgery. Change in MoCA test (ΔMoCA) was calculated.

RESULTS

Postoperative MoCA score was significantly greater in Group CI (25.2±2.4) than Group MAP (23.9±2.5) (P=0.046). The ΔMoCAs were 1 (IQR, 0-3) and 3 (IQR, 2-3.5) in Group CI and MAP respectively (P<0.001). Lowest and average rScO<inf>2</inf> values were significantly greater, and the decreased load of rScO2 below the threshold of 10% (AUCΔ10%) and 20% (AUCΔ20%) below its baseline were significantly lower in Group CI (P<0.05).

CONCLUSIONS

CI-based hemodynamic management provided better postoperative cognitive function and higher intraoperative rScO2 when compared with MAP-based hemodynamic management.

Gut microbiota: a new player in the pathogenesis of perioperative neurocognitive disorder?

Perioperative neurocognitive disorder (PND), including postoperative delirium and postoperative cognitive dysfunction (POCD), is a common postoperative complication in elderly patients, who represent an expanding segment of our population. PND is a multifactorial disease resulting in higher morbidity and mortality. The precise mechanism of PND is yet to be fully delineated. Identifying the modifiable risk factors and mechanisms for PND would be an important step forward in preventing such adverse events and thus improving patients' outcomes. It is increasingly recognized that gut microbiota also manifest effects in the central nervous system via the microbiota-gut-brain axis, which has emerged as an important player in shaping aspects of behavior and cognitive function. Recent studies have found that patients with cognitive dysfunction after surgery and anesthesia have obvious gut microbiome disorders. These findings are paralleled by a growing body of preclinical investigations aimed at better understanding how surgery and anesthesia affect the central nervous system and possibly contribute to cognitive decline. Here, we present a broad topical review of the literature supporting the role of gut microbiota in PND. We provide an overview of the mechanisms underlying the pathogenesis of PND from pre-clinical and human studies. Therefore, gut microbiota could be a putative therapeutic target for PND in the future.

Choosing Neuroanaesthesia as a career: Marching towards new horizons

Anaesthesiology is an ever-changing science and amongst its sub-specialities, the field of neuroanaesthesia is making rapid strides. The fragility of the brain and spinal cord and the multitude of complexities involved in neurosurgery and interventional neuroradiological procedures demand dedicated training in neuroanaesthesia. With rapid advancement in other neuroscience specialties, neuroanaesthesia too has made outstanding progress, owing to establishment of structured training, publication of high-quality scientific research, and invention of novel medications and monitoring modalities. The opportunities for training in India and abroad and resources to broaden knowledge in neuroanaesthesia have increased over the last two decades. A career in neuroanaesthesia offers a great future for budding anaesthesiologists.

Neuroanesthesiology Update

This review summarizes the literature published in 2020 that is relevant to the perioperative care of neurosurgical patients and patients with neurological diseases as well as critically ill patients with neurological diseases. Broad topics include general perioperative neuroscientific considerations, stroke, traumatic brain injury, monitoring, anesthetic neurotoxicity, and perioperative disorders of cognitive function.

Predictors of swallowing outcomes in patients with combat-injury related dysphagia

BACKGROUND

Traumatic injuries, such as those from combat-related activities, can lead to complicated clinical presentations that may include dysphagia.

METHODS

This retrospective observational database study captured dysphagia-related information for 215 US military service members admitted to the first stateside military treatment facility after sustaining combat-related or combat-like traumatic injuries. A multidimensional relational database was developed to document the nature, course, and management for dysphagia in this unique population and to explore variables predictive of swallowing recovery using Bayesian statistical modeling and inferential statistical methods.

RESULTS

Bayesian statistical modeling revealed the importance of maxillofacial fractures and soft tissue loss as primary predictors of poor swallowing outcomes. The presence of traumatic brain injury (TBI), though common, did not further complicate dysphagia outcomes. A more detailed examination and rating of videofluoroscopic swallow studies from a subset of 161 participants supported greater impairment for participants with maxillofacial trauma and no apparent relationship between having sustained a TBI and swallow functioning.

CONCLUSION

These analyses revealed that maxillofacial trauma is a stronger indicator than TBI of dysphagia severity and slower or incomplete recovery following combat-related injuries.

LEVEL OF EVIDENCE

Therapeutic/Care Management study, level IV.