European Society of Anaesthesiology evidence-based and consensus-based guideline on postoperative delirium

Effects of preconditioning by nasal splint and mouth breathing on emergence delirium after functional endoscopic sinus surgery in Chinese adults: a study protocol for a randomised controlled trial

INTRODUCTION

Emergence delirium (ED) is a common adverse manifestation after general anaesthesia and may result in undesirable consequences. Its causes and mechanisms are diverse and complex, and it is still unavoidable in clinical work. There is a high incidence of ED after otorhinolaryngology surgery, which may result from the sudden loss of functional senses and discomfort of surgical organs. This study aims to test a non-invasive, non-drug treatment modality of nose clamping and mouth-breathing training before surgery to reduce ED.

METHODS AND ANALYSIS

This prospective randomised controlled trial (RCT) will include 200 patients who undergo functional endoscopic sinus surgery (FESS) at Shanghai General Hospital, China. Study participants will be randomly assigned in two groups with a 1:1 ratio. The pretreatment group (P-group) will receive an intervention by nasal splint and mouth-breathing training before surgery, while the control group (C-group) will not receive any intervention; following which both groups will undergo FESS under general anaesthesia in accordance with the same anaesthesia scheme. After surgery, we will perform a single-blinded assessment of ED occurrence with stratification. IBM SPSS Statistics V.20 statistical software will be used for statistical analyses. A X² test will be used to compare the two groups, and t-tests will determine the statistical significance of continuous variables.

ETHICS AND DISSEMINATION

This RCT was designed in accordance with the principles of the Declaration of Helsinki and has been approved by the Ethics Committee of Shanghai General Hospital, ID: 2019KY039.We expect to release the original data in February 2022 on the ResMan original data sharing platform (IPD sharing platform) of the China clinical trial registry, which can be viewed at the following website:http://www.medresman.org.cn/pub/cn/proj/projectshow.aspx?proj=6293.

TRIAL REGISTRATION NUMBER

ChiCTR1900024925.

Technical considerations when using the EEG export of the SEDLine Root device

Electroencephalographic (EEG) patient monitoring during general anesthesia can help to assess the real-time neurophysiology of unconscious states. Some monitoring systems like the SEDLine Root allow export of the EEG to be used for retrospective analysis. We show that changes made to the SEDLine display during recording affected the recorded EEG. These changes can strongly impact retrospective analysis of EEG signals. Real-time changes of the feed speed in the SEDLine Root device display modifies the sampling rate of the exported EEG. We used a patient as well as a simulated EEG recording to highlight the effects of the display settings on the extracted EEG. Therefore, we changed EEG feed and amplitude resolution on the display in a systematic manner. To visualize the effects of these changes, we present raw EEG segments and the density spectral array of the recording. Changing the display’s amplitude resolution affects the amplitudes. If the amplitude resolution is too fine, the exported EEG contains clipped amplitudes. If the resolution is too coarse, the EEG resolution becomes too low leading to a low-quality signal making frequency analysis impossible. The proportion of clipped or zero-line data caused by the amplitude setting was > 60% in our sedated patient. Changing the display settings results in undocumented changes in EEG amplitude, sampling rate, and signal quality. The occult nature of these changes could make the analysis of data sets difficult if not invalid. We strongly suggest researchers adequately define and keep the EEG display settings to export good quality EEG and to ensure comparability among patients.

Perioperative management of patients with undergoing durable mechanical circulatory support

Durable mechanical circulatory support (MCS) devices revolutionized the treatment options for patients with end-stage heart failure (HF). Implantation of durable mechanical support has become an integral treatment modality in end-stage HF patients and it is associated with improved quality of life and survival. There is no doubt that this needs an interdisciplinary and interprofessional approach of cardiac surgeons, cardiologists, cardiac anesthesiologists, perfusionists, intensivists, psychologists, assist device coordinators as well as physiotherapists and intensive care. Implantation of durable MCS is a challenging procedure for the anesthesiologist due to the patient’s characteristics and comorbid diseases. It demands comprehensive training, high vigilance and quick response during the acute hemodynamic changes occurring during the surgery. Preoperative risk stratification is of major importance to guide perioperative medical treatment strategies. Most of these patients have several comorbidities and multiple medications. Therefore, to anticipate postoperative end-organ dysfunction such as cognitive dysfunction, pulmonary or renal failure, an interdisciplinary approach is necessary to optimize patient’s prior surgery. Transthoracic and transesophageal echocardiography (TTE and TEE), both play an invaluable role in diagnosing the cause and guiding the management in different unstable clinical situations. Especially prevention of postoperative right HF with subsequent necessity of temporary MCS is important as it is associated with higher mortality. The aim of this review is to provide an overview about the current concepts of perioperative management for durable MCS. A multimodal standard operating procedure supports early recovery after surgery and intensive care stay. Standardized perioperative care helps to ensure optimal medical treatment. This review focusses on several major skills of perioperative management of these high-risk surgical patients.

Interventions to improve perioperative neurologic outcomes

PURPOSE OF REVIEW

Few outcomes in surgery are as important to patients as that of their neurologic status. The purpose of this review is to discuss and categorize the most common perioperative neurologic complications. We will also discuss strategies to help prevent and mitigate these complications for our patients.

RECENT FINDINGS

There are several strategies the anesthesiologist can undertake to prevent or treat conditions, such as perioperative neurocognitive disorders, spinal cord ischemia, perioperative stroke, and postoperative visual loss.

SUMMARY

A thorough understanding of threats to patients' neurologic well-being is essential to excellent clinical practice.

The correlation of intraoperative hypotension and postoperative cognitive impairment: a meta-analysis of randomized controlled trials

BACKGROUND

There is no consensus on whether intraoperative hypotension is associated with postoperative cognitive impairment. Hence, we performed a meta-analysis to evaluate the correlation of intraoperative hypotension and the incidence of postoperative delirium (POD) or postoperative cognitive dysfunction (POCD).

METHODS

We searched PubMed, Embase, and Cochrane Library databases to find randomized controlled trials (RCTs) in which reported the relationship between intraoperative hypotension and POD or POCD. The retrieval time is up to January 2020, without language restrictions. Quality assessment of the eligible studies was conducted by two researchers independently with the Cochrane evaluation system.

RESULTS

We analyzed five eligible RCTs. Based on the relative mean arterial pressure (MAP), participants were divided into low-target and high-target groups. For the incidence of POD, there were two studies with 99 participants in the low-target group and 94 participants in the high-target pressure group. For the incidence of POCD, there were four studies involved 360 participants in the low-target group and 341 participants in the high-target group, with a study assessed both POD and POCD. No significant difference between the low-target and the high-target group was observed in the incidence of POD (RR = 3.30, 95% CI 0.80 to 13.54, P = 0.10), or POCD (RR = 1.26, 95% CI 0.76 to 2.08, P = 0.37). Furthermore, it also demonstrates that intraoperative hypotension prolonged the length of ICU stay, but did not increased the mortality, the length of hospital stay, and mechanical ventilation (MV) time.

CONCLUSIONS

There is no significant correlation between intraoperative hypotension and the incidence of POD or POCD.

Multi-disciplinary and pharmacological interventions to reduce post-operative delirium in elderly patients: A systematic review and meta-analysis

STUDY OBJECTIVE

An estimated 80% of older people undergoing surgery develop postoperative delirium (POD) making them a high-risk group. Research in this area is growing fast but there is no established consensus on strategies for POD prevention or management. A systematic review and meta-analysis were conducted to synthesise data on clinical interventions used to reduce POD among older people undergoing elective and emergency surgery.

METHODS

A range of database searches generated 336 papers. A total of 25 studies met the inclusion criteria and were assessed using the Joanna Briggs Institute Critical Appraisal Checklist. The studies were undertaken across the world.

RESULTS

This review identified a range of intervention approaches: comparisons between anaesthetic and sedatives agents, medication-specific interventions and multidisciplinary models of care. Results found more consistencies across multidisciplinary interventions than the pharmacological interventions. In pooled analyses, haloperidol (OR 0.74; 95% CI (confidence interval) 0.44, 1.26) was not statistically significantly associated with reduced POD incidence any more than a placebo.

CONCLUSION

There is a need to implement multidisciplinary interventions, as well as collaboration between clinicians on pre- and postoperative care practices regarding pharmacological interventions to more effectively reduce and manage POD in older people.

The concept of peri-operative medicine to prevent major adverse events and improve outcome in surgical patients: A narrative review

: Peri-operative Medicine is the patient-centred and value-based multidisciplinary peri-operative care of surgical patients. Peri-operative stress, that is the collective response to stimuli occurring before, during and after surgery, is, together with pre-existing comorbidities, the pathophysiological basis of major adverse events. The ultimate goal of Peri-operative Medicine is to promote high quality recovery after surgery. Clinical scores and/or biomarkers should be used to identify patients at high risk of developing major adverse events throughout the peri-operative period. Allocation of high-risk patients to specific care pathways with peri-operative organ protection, close surveillance and specific early interventions is likely to improve patient-relevant outcomes, such as disability, health-related quality of life and mortality.

Postoperative neurocognitive disorders

A decline in cognitive function is a frequent complication of major surgery. Postoperative cognitive impairments have generally been divided into short- (postoperative delirium) and long-term disturbances (postoperative cognitive dysfunction [POCD]). Long-term impairments are often subtle and overlooked. They need to be objectively assessed using neuropsychological tests to be diagnosed. Although POCD has been the subject of considerable research over the past decades, it remains uncertain why some patients do not return to preoperative levels of cognitive function. Surgery and anesthesia have both been implicated to play a role in POCD development, and certain patient-related factors, such as advanced age and low preoperative baseline cognitive function, have consistently been found to predict postoperative cognitive decline. This article will present an overview of POCD and its etiology and provide advice on possible strategies on its prevention.

Enhanced recovery programs in gastrointestinal surgery: Actions to promote optimal perioperative nutritional and metabolic care

The enhanced recovery after surgery (ERAS) pathway is an evidence-based approach to the use of care elements along the patient perioperative pathway. All care elements that may impact on clinically relevant outcomes have been considered and reviewed. The combined ERAS actions allow a quicker return to bowel function, oral feeding, nutritional and metabolic equilibrium, normal activity and ultimately to achieve better outcomes. Because of the multi factorial approach and the commitment of all the professionals caring for the patient, it is necessary to have the engagement of all disciplines, such as surgery, anesthesiology, clinical nutrition, nursing, physiatry, involved. ERAS is a dynamic process and new evidence are constantly integrated into the program. The primary endpoint of this review is to give updated information on the key ERAS actions to achieve optimal perioperative nutritional and metabolic care.

American Society for Enhanced Recovery and Perioperative Quality Initiative Joint Consensus Statement on Postoperative Delirium Prevention

Postoperative delirium is a geriatric syndrome that manifests as changes in cognition, attention, and levels of consciousness after surgery. It occurs in up to 50% of patients after major surgery and is associated with adverse outcomes, including increased hospital length of stay, higher cost of care, higher rates of institutionalization after discharge, and higher rates of readmission. Furthermore, it is associated with functional decline and cognitive impairments after surgery. As the age and medical complexity of our surgical population increases, practitioners need the skills to identify and prevent delirium in this high-risk population. Because delirium is a common and consequential postoperative complication, there has been an abundance of recent research focused on delirium, conducted by clinicians from a variety of specialties. There have also been several reviews and recommendation statements; however, these have not been based on robust evidence. The Sixth Perioperative Quality Initiative (POQI-6) consensus conference brought together a team of multidisciplinary experts to formally survey and evaluate the literature on postoperative delirium prevention and provide evidence-based recommendations using an iterative Delphi process and Grading of Recommendations Assessment, Development and Evaluation (GRADE) Criteria for evaluating biomedical literature.

Emergence Delirium in Elderly Patients as a Potential Predictor of Subsequent Postoperative Delirium: A Descriptive Correlational Study

PURPOSE

This study aimed to investigate the incidence of emergence delirium (ED) in elderly patients under general anesthesia and to determine the correlation between ED and delirium at five subsequent postoperative days.

DESIGN

This research is a descriptive correlational study.

METHODS

A total of 168 aged patients undergoing elective general anesthesia were recruited from a comprehensive tertiary teaching hospital with 2,400 beds in Southern China from April 2018 to September 2018. The Nursing Delirium Screening Scale was used to assess delirium at 30 and 60 minutes after extubation or on discharge from the postanesthesia care unit. Patients were assessed for delirium at postoperative days one through five using the same method. Patients' demographic information, including cognitive function, were collected.

FINDINGS

Among the 168 aged patients, 58 suffered from ED (34.5%), including the 79.3% for the 46 patients who experienced postoperative delirium (POD). A positive correlation existed between ED and POD (χ² = 111.744; P < .01). Logistic regression analysis included seven variables: age, preoperative Mini-Mental State Examination score, underlying diseases, American Society of Anesthesiologists grade, surgery duration, postoperative complications, and the presence of ED. Age and ED were concluded to be independent predictive factors of POD.

CONCLUSIONS

ED in the first hour after tracheal tube removal is a predictor of delirium at five subsequent postoperative days. Accurate and timely assessment of recovery period can effectively guide the treatment and rehabilitation of POD and maximize prevention of adverse consequences.

Peri-operative management of frailty in the orthopedic patient

The purpose of this investigation was to summarize current research on diagnosis, outcomes, and management of frail patients undergoing orthopedic surgery. Because frail patients are at increased risk of negative post-operative outcomes including increased 30-day mortality and post-operative complications including infections and delirium, such a review is timely. Strategies including supervised exercise training programs before surgery, early identification of frailty, prophylactic antibiotics, regular drug chart review, regular monitoring of electrolytes, and other strategies to prevent post-operative delirium are helpful in the management of frail orthopedic patients. It is important for surgeons and anesthesiologists to take action in attempt to alleviate adverse post-operative outcomes in frail patients. Ultimately, more research is needed to identify new strategies and to evaluate whether pre-operative optimization can effectively mitigate post-operative outcomes in large-scale randomized controlled trials.

Perioperative Management of Alcohol Withdrawal Syndrome

Background

In the perioperative course, alcohol withdrawal syndrome (AWS) can occur in any setting, especially in aero-digestive and acute trauma surgery. Challenging issues are the overlap of other forms of delirium in perioperative and intensive care settings as well as general anesthesia masking the onset of withdrawal symptoms. In contrast to other etiologies of delirium, the pathophysiology and thus treatment strategy of AWS is different: the key point is the tolerance to GABAergic molecules of alcohol-dependent subjects resulting in central nervous hyperactivity once the effect of alcohol or other GABA-stimulating agents is decreased.

Summary

Despite limitations due to insufficient accuracy of self-reporting questionnaires and limited feasibility in emergency settings, the AUDIT and the shortened AUDIT-C are the standard tools for detection of alcohol use disorders (AUD), as well as predicting AWS risk and severity in approximately half of these AUD patients. The most important risk factors for AWS are a high blood alcohol concentration at hospital admission, AWS episodes in medical history, and lack of control of alcohol use. Patients considered at risk for severe AWS must be treated with prophylactic medication before the onset of symptoms. Thiamine supplementation is required for all malnourished alcohol-dependent patients. Writing down alcohol-related diagnoses in the medical records requires the patient's presumed consent after shared decision-making. These reports should remain strictly confidential if the patient desires. Psychological support for the perioperative period as well as the following course should be offered to all AUD patients including support in short- and long-term detoxification. Alternative diagnoses must be ruled out with no timely delay, especially if fever and coma are the leading symptoms. The backbone of AWS therapy is the symptom-triggered administration of intravenous benzodiazepines (BZO) in escalating doses until the aimed revised Clinical Institute Withdrawal Assessment for Alcohol Scale (CIWA-Ar) or Richmond Agitation-Sedation Scale (RASS) score is achieved. Clonidine, dexmedetomidine, baclofen, ketamine, and neuroleptics may be used as symptom-orientated adjuncts. The therapeutic administration of ethanol or clomethiazole is considered to be harmful in critically ill patients after the onset of AWS. General supportive and intensive care including high-dose thiamine supplementation are mandatory in severe AWS cases. The timely differential diagnosis of delirium is important - and AWS is a diagnosis of exclusion - because BZO are strongly recommended for AWS patients but may not be the treatment of choice in other etiologies of delirium.

Key Messages

Screening for AWS risk factors should be integrated in the preoperative and emergency assessment. Other severe diagnoses must be ruled out before the diagnosis of AWS can be established. Preventive treatment should be given to high-risk patients scoring positive for AUD and for patients with a lack of alcohol use control. The principles of AWS therapy are symptom-orientated doses of BZO and as adjuncts α₂-agonists, neuroleptics, and others guided by repeated reassessment with validated tools and thiamine administration. Length of stay and morbidity are reduced if AWS therapy is symptom-orientated and protocol-based.

Electroencephalography: Clinical Applications During the Perioperative Period

Electroencephalography (EEG) monitoring has become technically feasible in daily clinical anesthesia practice. EEG is a sensitive method for detecting neurophysiological changes in the brain and represents an important frontier in the monitoring and treatment of patients in the perioperative period. In this review, we briefly introduce the essential principles of EEG. We review EEG application during anesthesia practice in the operating room, including the use of processed EEG in depth of anesthesia assessment, raw EEG monitoring in recognizing brain states under different anesthetic agents, the use of EEG in the prevention of perioperative neurocognitive disorders and detection of cerebral ischemia. We then discuss EEG utilization in the intensive care units, including the use of EEG in sedative level titration and prognostication of clinical outcomes. Existing literature provides insight into both the advances and challenges of the clinical applications of EEG. Future study is clearly needed to elucidate the precise EEG features that can reliably optimize perioperative care for individual patients.

Clinical practice in the management of postoperative delirium by Chinese anesthesiologists: a cross-sectional survey designed by the European Society of Anaesthesiology

OBJECTIVE

In this survey, we assessed the current clinical management of postoperative delirium (POD) among Chinese anesthesiologists, after publishing the European POD guideline.

METHODS

We administered an electronic survey, designed according to the European POD guideline. The survey was completed using mobile devices.

RESULTS

In total, 1,514 respondents from China participated in the survey. Overall, 74.4% of participants reported that delirium is very important. More than 95% of participants stated that they routinely assessed POD. In total, 61.4% screened for POD using clinical observation and 37.6% used a delirium screening tool. Although the depth of anesthesia (a POD risk factor) was monitored, electroencephalogram monitoring was unavailable to 30.6% of respondents. Regarding treatment, only 24.1% of respondents used a standard algorithm; 58.5% used individualized treatment.

CONCLUSION

Our survey showed that there are high awareness levels among Chinese anesthesiologists regarding the importance of POD. However, routine assessment and monitoring of all patients, including perioperative anesthesia depth monitoring, and a treatment algorithm need to be implemented on a larger scale. According to the results, efforts should be made to improve the knowledge of POD among Chinese anesthesiologists.

Episodes of psychomotor agitation among medical patients: findings from a longitudinal multicentre study

BACKGROUND

The management of delirium among older in-hospital patients is a challenge, leading to worse outcomes, including death. Specifically, psychomotor agitation, one of the main characteristics of hyperactive delirium, requires a significant amount of medical and nursing surveillance. However, despite its relevance, to date incidence and/or prevalence of psychomotor agitation, its predictors and outcomes have not been studied among Italian older patients admitted in medical units.

AIMS

To describe the incidence and the prevalence of psychomotor agitation among patients aged > 65 years admitted to medical units and identify predictors at the individual, nursing care and hospital levels.

METHODS

A longitudinal multicentre study was conducted involving 12 medical units in 12 northern Italian hospitals. Descriptive, bivariate and multivariate logistic regression analyses were performed.

RESULTS

Among the 1464 patients included in the study, two hundred (13.6%) have manifested episode(s), with an average of 3.46/patient (95% confidence of interval [CI] 2.73-4.18). In 108 (54.0%) patients, episode(s) were present also in the week prior to hospitalisation: therefore, in-hospital-acquired psychomotor agitation was reported in 92 patients (46%). The multivariate logistic regression analysis explained the 25.4% of the variance and identified the following variables as psychomotor agitation predictors: the risk of falls (relative risk [RR] 1.314, 95% CI 1.218-1.417), the amount of missed nursing care (RR 1.078, 95% CI 1.037-1.12) and the patient's age (RR 1.018, 95% CI 1.002-1.034). Factors preventing the occurrence of episode(s) were: the amount of care received from graduated nurses (RR 0.978; 95% CI 0.965-0.992) and the lower functional dependence at admission (RR 0.987, 95% CI 0.977-0.997).

CONCLUSIONS

A considerable number of elderly patients admitted in medical units develop psychomotor agitation; its predictors need to be identified early to inform decisions regarding the personal care needed to prevent its occurrence, especially by acting on modifiable factors, such as the risk of falls, missed nursing care and functional dependence.

Perioperative care of older persons: where are we?

not available.

Implementation of strategies to prevent and treat postoperative delirium in the post-anesthesia caring unit : A German survey of current practice

Postoperative delirium is associated with worse outcome. The aim of this study was to understand present strategies for delirium screening and therapy in German Post-Anesthesia-Caring-Units (PACU). We designed a German-wide web-based questionnaire which was sent to 922 chairmen of anesthesiologic departments and to 726 anesthetists working in ambulatory surgery. The response rate was 30% for hospital anesthesiologists. 10% (95%-confidence interval: 8–12) of the anesthesiologists applied a standardised screening for delirium. Even though not on a regular basis, in 44% (41–47) of the hospitals, a recommended and validated screening was used, the Nursing Delirium Screening Scale (NuDesc) or the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). If delirium was likely to occur, 46% (43–50) of the patients were examined using a delirium tool. 20% (17–23) of the patients were screened in intensive care units. For the treatment of delirium, alpha-2-agonists (83%, 80–85) were used most frequently for vegetative symptoms, benzodiazepines for anxiety in 71% (68–74), typical neuroleptics in 77% (71–82%) of patients with psychotic symptoms and in 20% (15–25) in patients with hypoactive delirium. 45% (39–51) of the respondents suggested no therapy for this entity. Monitoring of delirium is not established as a standard procedure in German PACUs. However, symptom-oriented therapy for postoperative delirium corresponds with current guidelines.

Melatonin and its analogues for the prevention of postoperative delirium: A systematic review and meta-analysis

It remains unclear whether melatonin and its analogues prevent postoperative delirium (POD). Therefore, we conducted a systematic review and meta-analysis to evaluate the effect of melatonin and its analogues on POD prevention. PubMed, Cochrane Library, Web of Science, Embase and CINAHL databases were searched. Primary outcome was the incidence of POD. Six randomized controlled trials, 2 cohort studies and 1 case-control study were included in this meta-analysis. Results showed that melatonin and its analogue ramelteon decreased the incidence of POD in the entire adult surgical population (odds ratio [OR] = 0.45, 95% confidence interval [CI] 0.24-0.84, P = .01). When administered at a higher dose (5 mg), melatonin was effective in reducing the POD incidence (OR = 0.32, 95% CI 0.20-0.52, P < .00001). Melatonin administered less than 5 elimination half-lives before the surgery significantly reduced the POD incidence (OR = 0.31, 95% CI 0.19-0.49, P < .00001). Current literature supports the effectiveness of melatonin and its analogue ramelteon in POD prevention. However, the present study was limited by the significant heterogeneity of the included studies. More studies are needed to ascertain the preventive effect of melatonin and its analogues on the incidence of delirium after cardiac and noncardiac surgeries.

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.

The Impact of Anesthetic Regimen on Outcomes in Adult Cardiac Surgery: A Narrative Review

Despite improvements in surgical techniques and perioperative care, cardiac surgery still is burdened by relatively high mortality and frequent major postoperative complications, including myocardial dysfunction, pulmonary complications, neurologic injury, and acute kidney injury. Although the surgeon's skills and volume and patient- and procedure-related risk factors play a major role in the success of cardiac surgery, there is growing evidence that also optimizing perioperative care may improve outcomes significantly. The present review focuses on the aspects of perioperative care that are strictly related to the anesthesia regimen, with special reference to volatile anesthetics and neuraxial anesthesia, whose effect on outcome in adult cardiac surgery has been investigated extensively.

Predicting Intense Levels of Child Anxiety During Anesthesia Induction at Hospital Arrival

In children, intense levels of anxiety during anesthetic induction are associated with a higher risk of pain, poor recovery, and emergence delirium. Therefore, it is important to identify these high-risk children at hospital arrival. The current study examined internalizing behavior (Child Behavior Checklist, CBCL) and state anxiety measures (modified Yale Preoperative Anxiety Scale, mYPAS, and State Trait Anxiety Inventory for Children, STAIC) at hospital arrival as predictors of anxiety during induction of anesthesia. One hundred children (aged 4 to 12 years) undergoing elective daycare surgery were included. The STAIC and mYPAS at hospital arrival were significant predictors of anxiety during induction, whereas CBCL was not. The STAIC state form at hospital arrival was the strongest predictor and could be used to identify children who will experience intense levels of anxiety during anesthetic induction, with sufficient to good diagnostic accuracy. Using the STAIC at hospital arrival allows targeted interventions to reduce anxiety in children.

Intra-operative hyperoxia and the risk of delirium in elderly patients after cardiac surgery

Delirium is a common complication after cardiac surgery. The aim of our study was to determine the impact of hyperoxia episodes occurring during cardiopulmonary bypass (CBP) on the rate of delirium episodes in the postoperative period. 93 patients, aged ≥ 65, who underwent elective cardiac surgery (CBP <90 minutes) were enrolled. The occurrence of delirium episodes was examined every 12 hours for three days after surgery. Eleven patients (11.8%) developed postoperative delirium (POD (+)) and 83 did not (POD (-)). More incidences of severe hyperoxia (PaO2 ≥ 26.6kPa) during CBP were observed in the POD (+) group: 64% had ≥ 2 episodes of hyperoxia, 27% ≥ 3, and 18% ≥ 4, while in the POD (-) group: 42%, 13% and 1%, respectively (P=0.02). Patients in the POD (+) group had a higher maximum PaO₂ during CBP than the POD (-) group (37 ± 5.8 vs 31.6 ± 6.6 kPa; P=0.01) and a higher mean PaO₂ (30.1 ± 4.5 vs 26.1 ± 5.6 kPa; P=0.01). The optimal maximum PaO₂ cut-off point for the occurrence of delirium was 33.2 kPa (AUC 0.72, P=0.001, sensitivity 75%, specificity 38%). We conclude that CBP hyperoxia episodes may be a risk factor associated with the occurrence of postoperative delirium.

Patient-related and anesthesia-dependent determinants for postoperative delirium after oral and maxillofacial surgery. Results from a register-based case-control study

OBJECTIVE

To identify risk factors for postoperative delirium (POD) after general oral and maxillofacial surgery.

MATERIAL AND METHODS

2420 patients were screened postoperatively for POD using the Nursing Delirium Screening Scale (NuDESC) before discharge from the post anesthesia caring unit (PACU). Basic health data and risk factors were collected. For analysis the study group (n=41) was compared to a control group of 164 randomly selected patients (case-control-ratio=1:4). To identify risk factors for POD multivariable logistic regression models were used. To see whether estimations remain stable, regression analysis was repeated for the subgroup of patients not undergoing dentoalveolar surgery (n=105). To estimate the risk for dentoalveolar surgery a logistic regression model was performed.

RESULTS

Dementia was the only significant risk factor for POD (Odds ratio 41.5; 95% CI 5.48-314), also for patients undergoing other than dentoalveolar surgery (58.1; 1.70-1983). Patients undergoing dentoalveolar surgery were more often suffering from dementia (35.5; 2.85-441), other psychiatric and neurological disorders (3.15; 1.05-9.43), were of younger age (0.97; 0.94-1.00) and had higher anesthesiological risk (3.95; 1.04-14.9).

CONCLUSION

Patients with dementia are at higher risk to develop POD after oral and maxillofacial surgery. We found a strong interdependence between age, dementia, ASA-Score and dentoalveolar surgery.

Intraoperative xenon for prevention of delirium after on-pump cardiac surgery: a randomised, observer-blind, controlled clinical trial

BACKGROUND

Older patients undergoing cardiac surgery have a 40-60% risk of developing postoperative delirium (POD), which is associated with increased morbidity and mortality. In animals, xenon has been found to be neuroprotective. Little is known about its neuroprotective effects in humans. We evaluated whether xenon anaesthesia prevents POD in patients undergoing cardiac surgery.

METHODS

We conducted a randomised, observer-blind, controlled trial in which 190 patients 65 yr or older undergoing on-pump cardiac surgery were randomly allocated to xenon or sevoflurane anaesthesia. During cardiopulmonary bypass, propofol infusion was used for anaesthetic maintenance. Subjects were screened for POD daily during the first 5 postoperative days using the 3-Minute Diagnostic Interview for Confusion Assessment Method (CAM) or with a CAM version for patients in ICU (CAM-ICU). Other methods to detect delirium, such as chart review, were also used. Secondary outcomes included the duration and severity of POD, and postoperative cognitive function.

RESULTS

The overall incidence of POD was 41% (78/190). There was no statistically significant difference in the POD incidence between the xenon and sevoflurane groups (42.7% [41/96] vs 39.4% [37/94], P=0.583). The odds ratio for POD when comparing xenon with sevoflurane was 1.18 (95% confidence interval, 0.65-2.16).

CONCLUSIONS

In older patients undergoing cardiac surgery, xenon anaesthesia did not result in a significant reduction in POD. Based on these results alone, use of xenon cannot be recommended for this purpose.

CLINICAL TRIAL REGISTRATION

EudraCT: 2014-005370-11 (May 13, 2015; https://www.clinicaltrialsregister.eu/ctr-search/search?query=2014-005370-11).

Routine management of postoperative delirium outside the ICU: Results of an international survey among anaesthesiologists

BACKGROUND

Postoperative delirium (POD) is a severe brain dysfunction. Although data indicate a high relevance, no survey has investigated the routine practice to monitor delirium outside the ICU setting after surgery. Prior to publishing of the new European Society of Anaesthesiology (ESA) guidelines on POD, an international survey was conducted to assess current practice.

METHODS

European Society of Anaesthesiology-endorsed online survey; Trial Registration: NCT-identifier: 02513537.

RESULTS

In total, 566 respondents from 62 countries accessed, and 564 (99.6%) completed the survey (completion rate). Overall, 385 (68%) of the respondents reported that delirium is either "very relevant" or "relevant" for their daily clinical practice. In all, 38 (7%) of the respondents routinely monitor for delirium in >50% of all patients. Asked on the monitoring time point, more than half (n = 308, 55%) indicated to screen before or at recovery room discharge, 235 (42%) up to the first postoperative day, 143 (25%) up to 3 days, and 77 (14%) up to 5 postoperative days. Although there is a lack of long-term monitoring, nearly all respondents (n = 530, 94%) reported to treat delirium. Availability of EEG/EMG-based monitoring to assess the depth of anaesthesia was high in the study group (n = 547, 97%) and was used by more than one-third of the respondents to reduce risk of burst suppression (n = 189, 34%).

CONCLUSION

Although delirium is perceived as a relevant condition among anaesthesiologists, there is a high demand for implementing monitoring strategies after publishing of the POD Guideline. The survey shows that tools necessary for POD Guideline implementation are available in the centres represented by the respondents.

Depressive and/or anxiety scoring instruments used as screening tools for predicting postoperative delirium after cardiac surgery: A pilot study

BACKGROUND

Depression is common in patients with cardiac disease. Depression is a risk factor for developing postoperative delirium, a common and serious complication to cardiac surgery.

OBJECTIVES

The aim was to evaluate if screening tools for depression can be used to predict postoperative delirium after cardiac surgery.

METHODS

This was a prospective population-based pilot study including 26 patients between 23 and 80 years of age undergoing cardiac surgery in Sweden during 2018. The day before surgery the participants filled out the depression screening instruments Hospital Anxiety and Depression Scale and Patient Health Questionnaire. After discharge the patient charts were examined for documentation of symptoms of delirium.

RESULTS

Five (20%) patients screened positive regarding depression using the Hospital Anxiety and Depression Scale and 7 patients (27%) screened positive using The Patient Health Questionnaire. Four (22%) patients showed symptoms of postoperative delirium, none of them screened positive for depression prior to surgery.

CONCLUSION

We found no difference between the questionnaires PHQ-9 and HADS regarding identifying depressive symptoms. Moreover, we found that post-operative delirium, to a certain extent, can be detected by reading the patient́s charts postoperatively. However, this pilot study showed that screening tools for delirium need to be better implemented.

Development of delirium: Association with old age, severe burns, and intensive care

BACKGROUND

Delirium is defined as a disturbance of attention and awareness that develops over a short period of time, is a change from the baseline, and typically fluctuates over time. Burn care involves a high prevalence of known risk factors for delirium such as sedation, inflammation, and prolonged stay in hospital. Our aim was to explore the extent of delirium and the impact of factors associated with it for adult patients who have been admitted to hospital with burns.

METHODS

In this retrospective study, all adult patients who had been admitted with burns during a four-year period were studied, including both those who were treated with intensive care and intermediate care only (no intensive care). Daily records of the assessment of delirium using the Nursing Delirium Screening Scale (Nu-DESC) were analysed together with age, sex, the percentage of total body surface area burned, operations, and numbers of wound care procedures under anaesthesia, concentrations of plasma C-reactive protein, and other clinical variables. Logistic regression was used to analyse factors that were associated with delirium and its effect on mortality, and linear regression was used to analyse its effect on the duration of hospital stay.

RESULTS

Fifty-one patients (19%) of the total 262 showed signs of delirium (Nu-DESC score of 2 or more) at least once during their stay in hospital. Signs of delirium were recorded in 42/89 patients (47%) who received intensive care, and in 9/173 (5%) who had intermediate care. Independent factors for delirium in the multivariable regression were: age over 74 years; number of operations and wound care procedures under anaesthesia; and the provision of intensive care (area under the curve 0.940, 95% CI 0.899-0.981). Duration of hospital stay, adjusted for age and burn size, was 13.2 (95% CI 7.4-18.9, p < 0.001) days longer in the group who had delirium. We found no independent effects of delirium on mortality.

CONCLUSION

We found a strong association between delirium and older age, provision ofr intensive care, and number of interventions under anaesthesia. A further 5% of patients who did not receive intensive care also showed signs of delirium, which is a finding that deserves to be thoroughly investigated in the future.

Exosome α-Synuclein Release in Plasma May be Associated With Postoperative Delirium in Hip Fracture Patients

Background: Little is known about the underlying mechanisms of the similarities in the core features of postoperative delirium (POD) and α-synuclein (α-syn)-related cognitive disorders. We herein investigated associations between fluctuated levels of exosomal α-syn in the plasma and POD presentation in geriatric hip fracture patients.

Methods: We conducted an observational, prospective, and 1:1 matched (on age older than 65, hip fracture diagnosis, American Society of Anesthesiologist’ (ASA) physical status, duration of surgery, and intraoperative bleeding) case-control study: POD cases and non-POD controls were selected from the overall cohort by using Confusion Assessment Method (CAM). Delirium severity was measured by the Memorial Delirium Assessment Scale (MDAS). Plasma exosome levels of α-syn were examined preoperatively and at the time that POD was diagnosed, by using an established immunocapture technology based on a putative brain-cell-specific marker. Circulating concentrations of interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were also determined. The relationship between α-syn levels and POD risk, as well as the association between α-syn and MDAS scores and plasma cytokines, were assessed.

Results: POD incidence was 8.4% (17/202). Postoperative α-syn were either elevated or lowered. As primary outcome variables, the change of α-syn in POD patients was significantly higher than non-POD ones (21.0 ± 29.3 pg.ml⁻¹ vs.1.9 ± 20.0, P = 0.047). The α-syn alteration was positively correlated to MDAS (r = 0.436, P = 0.010) and the change of IL-6 (r = 0.383, P = 0.025).

Conclusions: Exosome α-syn release in plasma may be associated with the POD development which might be due to systemic inflammation.

Clinical Trial Registration: www.clinicaltrials.gov, identifier ChiCTR-IPR-17012301.

Prior Presentation: The abstract of this work has been selected for presentation in the 2019 ANESTHESIOLOGY Journal Symposium “What’s New with the old,” and it has been present in the ASA 2019 annual meeting October 21st, 2019 in Florida.

A comparative study on adequate anesthesia depth: clinical judgement and the Narcotrend® measurement

Purpose

To compare the clinical judgement of electroencephalogram (EEG)-naïve anesthesiologists with an EEG-based measurement of anesthetic depth (AD) using the Narcotrend® monitor.

Methods

In this prospective cohort study including 600 patients, AD during stable anesthesia was assessed by clinical judgement of the attending, EEG-blinded anesthesiologist (using a scale staging the AD as mid-adequate, adequate but fairly deep, or adequate but fairly light) and by simultaneously recorded Narcotrend measurements.

Results

In 42% of patients (n = 250), the anesthesiologist’s clinical judgement was in agreement with anesthetic levels as measured by the Narcotrend monitor. In 46% of patients (n = 274), the anesthesiologist’s judgement and the Narcotrend monitor differed by one AD level (minor discordance). Major discordance was observed in 76 (13%) measurements (judged deeper than measured, n = 29 [5%]; judged lighter than measured, n = 47 [8%]). In 7% of patients (n = 44), the Narcotrend index was outside the limits of adequate AD (too deep, n = 28 [5%]; too superficial, n = 16 [3%]). The overall level of agreement between the anesthesiologist’s judgement and the Narcotrend monitor was not statistically significant (Cohen’s kappa, −0.039; P = 0.17). Using a random forests algorithm, age, mean blood pressure, the American Society of Anesthesiologists classification, body mass index, and frailty were the variables with the highest relative feature importance to predict the level of agreement.

Conclusion

These results suggest that clinical judgement of AD during stable anesthesia was not in agreement with EEG-based assessment of anesthetic depth in 58% of cases. Nevertheless, this finding could be influenced by the lack of validated scales to clinically judge AD.

Trial registration

www.clinicaltrials.gov (NCT02766894); registered 10 May, 2016.

Perioperative Dexmedetomidine Supplement Decreases Delirium Incidence After Adult Cardiac Surgery: A Randomized, Double-Blind, Controlled Study

OBJECTIVE

Conflicting data exist on the effect of dexmedetomidine on delirium. For the present study, a randomized trial was performed to investigate the effect of perioperative dexmedetomidine on the rate of postoperative delirium after cardiac surgery.

DESIGN

A randomized controlled trial.

SETTING

University hospital.

PARTICIPANTS

Patients (n = 169) undergoing elective cardiac surgery (coronary artery bypass graft surgery, valve surgery, or combined surgery) with cardiopulmonary bypass.

INTERVENTIONS

Patients received a sevoflurane-based general anesthesia and were randomly assigned 1:1 to receive a dexmedetomidine infusion that started in the operating room (0.7 μg/kg/h) and continued into the intensive care unit (0.4 μg/kg/h) or an equivolume infusion of placebo.

MEASUREMENTS AND MAIN RESULTS

A decrease in the rate of delirium in the dexmedetomidine group compared with the placebo group was demonstrated (6 of 84 [7.1%] v 16 of 85 [18.8%]; p = 0.02; odds ratio [OR] 0.33 [95% confidence interval {CI} 0.12-0.90]). Reduced intensive care unit and hospital lengths of stay also were observed (18 [18-22] hours v 22 [18-39] hours; p = 0.002 and 17 [7-20] days v 19 [8-21] days; p = 0.04, respectively). Mortality at 30 days was 2 (2.4%) in both groups. On multivariate analysis, only dexmedetomidine administration (OR 0.24 [95% CI 0.08-0.74]) and cardiopulmonary bypass time (OR 1.02 [95% CI 1.01-1.03] for increases of 1 min) were independent predictors of delirium development.

CONCLUSIONS

Dexmedetomidine administered during and after general anesthesia for cardiac surgery with cardiopulmonary bypass decreased the rate of postoperative delirium and intensive care unit and hospital lengths of stay.

Adherence to recommended practices for perioperative anesthesia care for older adults among US anesthesiologists: results from the ASA Committee on Geriatric Anesthesia-Perioperative Brain Health Initiative ASA member survey

BACKGROUND

While specific practices for perioperative care of older adults have been recommended, little is known regarding adherence by US physician anesthesiologists to such practices. To address this gap in knowledge, the ASA Committee on Geriatric Anesthesia and the ASA Perioperative Brain Health Initiative undertook a survey of ASA members to characterize current practices related to perioperative care of older adults.

METHODS

We administered a web-based questionnaire with items assessing the proportion of practice focused on delivery of care to older adults, adherence to recommended practices for older surgical patients, resource needs to improve care, and practice characteristics.

RESULTS

Responses were collected between May 24, 2018, and June 29, 2018. A total of 25,587 ASA members were invited to participate, and 1737 answered at least one item (6.8%). 96.4% of respondents reported that they had cared for a patient aged 65 or older within the last year. 47.1% of respondents (95% confidence interval, 44.6%, 49.7%) reported using multimodal analgesia among patients aged 65 and older at least 90% of the time, and 25.5% (95% CI, 23.3%, 27.7%) provided preoperative information regarding postoperative cognitive changes at least 90% of the time. Over 80% of respondents reported that preoperative screening for frailty or dementia, postoperative screening for delirium, and preoperative geriatric consultation occurred in fewer than 10% of cases. Development of practice guidelines for geriatric anesthesia care and expansion of web-based resources were most frequently prioritized by respondents as initiatives to improve care in this domain.

DISCUSSION

Most survey respondents reported providing anesthesia care to older adults, but adherence to recommended practices varied across the six items assessed. Reported rates of screening for common geriatric syndromes, such as frailty, delirium, and dementia, were low among survey respondents. Respondents identified multiple opportunities for ASA initiatives to support efforts to improve care for older surgical patients.

Postoperative anaemia might be a risk factor for postoperative delirium and prolonged hospital stay: A secondary analysis of a prospective cohort study

BACKGROUND

Postoperative anaemia is a frequent surgical complication and in contrast to preoperative anaemia has not been validated in relation to mortality, morbidity and its associated health economic effect. Postoperative anaemia can predispose postoperative delirium through impairment of cerebral oxygenation. The aim of this secondary analysis is to investigate the association of postoperative anaemia in accordance with the sex specific World Health Organization definition of anaemia to postoperative delirium and its impact on the duration of hospital stay.

METHODS

A secondary analysis of the prospective multicentric observational CESARO-study was conducted. 800 adult patients undergoing elective surgery were enrolled from various operative disciplines across seven hospitals ranging from university hospitals, district general hospitals to specialist clinics of minimally invasive surgery in Germany. Patients were classified as anaemic according to the World Health Organization parameters, setting the haemoglobin level cut off below 12g/dl for females and below 13g/dl for males. Focus of the investigation were patients with acute anaemia. Patients with present preoperative anaemia or missing haemoglobin measurement were excluded from the sample set. Delirium screening was established postoperatively for at least 24 hours and up to three days, applying the validated Nursing Delirium Screening Scale.

RESULTS

The initial sample set contained 800 patients of which 183 were suitable for analysis in the study. Ninety out of 183 (49.2%) suffered from postoperative anaemia. Ten out of 93 (10.9%) patients without postoperative anaemia developed a postoperative delirium. In the group with postoperative anaemia, 28 (38.4%) out of 90 patients suffered from postoperative delirium (odds ratio 3.949, 95% confidence interval, (1.358-11.480)) after adjustment for NYHA-stadium, severity of surgery, cutting/suture time, duration of anaesthesia, transfusion of packed red cells and sedation status with Richmond Agitation Scale after surgery. Additionally, patients who suffered from postoperative anaemia showed a significantly longer duration of hospitalisation (7.75 vs. 12.42 days, odds ratio = 1.186, 95% confidence interval, 1.083-1.299, after adjustments).

CONCLUSION

The study results reveal that postoperative anaemia is not only a frequent postsurgical complication with an incidence probability of almost 50%, but could also be associated with a postoperative delirium and a prolonged hospitalisation.

Evaluating Mechanisms of Postoperative Delirium and Cognitive Dysfunction Following Elective Spine Surgery in Elderly Patients (CONFESS): Protocol for a Prospective Observational Trial

Background

Elderly people are at particular high risk for postoperative delirium (POD) following spine surgery, which is associated with longer hospital stays, higher costs, risk for delayed complications, long-term care dependency, and cognitive dysfunction (POCD). It is insufficiently understood which mechanisms and risk factors contribute to the development of POD and POCD following these major but plannable surgeries.

Objective

This study aims to identify modifiable risk factors in spine surgery. A better understanding thereof would help adapt medical management and surgical strategies to individual risk profiles.

Methods

This is a single-center observational study jointly conducted by the departments of neurosurgery, neurology, and anesthesiology at a tertiary care hospital in Germany. All patients aged 60 years and older presenting to the neurosurgery outpatient clinic or ward for elective spine surgery are screened for eligibility. Exclusion criteria include presence of neurodegenerative or history of psychiatric disease and medication with significant central nervous system activity (eg, antidepressants, antipsychotics, sedatives). Surgical and anesthetic procedures including duration of surgery as primary end point of this study are thoroughly documented. All patients are furthermore evaluated for their preoperative cognitive abilities by a number of tests, including the Consortium to Establish a Registry for Alzheimer's Disease Plus test battery. Physical, mental, and social health and well-being are assessed using the Patient-Reported Outcome Measurement Information System Profile 29 and Hospital Anxiety and Depression Scale. Patients additionally receive preoperative cerebrovascular ultrasound and structural and functional brain imaging. The immediate postoperative period includes screening for POD using the Nursing Delirium Screening Scale and validation through Diagnostic and Statistical Manual of Mental Disorders, 5th Edition, criteria. We furthermore investigate markers of (neuro)inflammation (eg, interleukins, C-reactive protein, tumor necrosis factor alpha). Preoperative examinations are repeated 3 months postoperatively to investigate the presence of POCD and its mechanisms. Statistical analyses will compare delirious and nondelirious patients for predictors of immediate (POD) and delayed (POCD) cognitive dysfunction.

Results

This is the first study to prospectively evaluate risk factors for POD and POCD in spine surgery. Recruitment is ongoing, and data collection is estimated to be finished with the inclusion of 200 patients by mid-2020.

Conclusions

The identification of mechanisms, possibly common, underlying POD and POCD would be a major step toward defining effective interventional strategies early in or even before the postoperative period, including the adaptation of surgical strategies to individual risk profiles.

Trial Registration

ClinicalTrials.gov NCT03486288; https://clinicaltrials.gov/ct2/show/NCT03486288

Anesthetic Management Using Multiple Closed-loop Systems and Delayed Neurocognitive Recovery: A Randomized Controlled Trial

BACKGROUND

Cognitive changes after anesthesia and surgery represent a significant public health concern. We tested the hypothesis that, in patients 60 yr or older scheduled for noncardiac surgery, automated management of anesthetic depth, cardiac blood flow, and protective lung ventilation using three independent controllers would outperform manual control of these variables. Additionally, as a result of the improved management, patients in the automated group would experience less postoperative neurocognitive impairment compared to patients having standard, manually adjusted anesthesia.

METHODS

In this single-center, patient-and-evaluator-blinded, two-arm, parallel, randomized controlled, superiority study, 90 patients having noncardiac surgery under general anesthesia were randomly assigned to one of two groups. In the control group, anesthesia management was performed manually while in the closed-loop group, the titration of anesthesia, analgesia, fluids, and ventilation was performed by three independent controllers. The primary outcome was a change in a cognition score (the 30-item Montreal Cognitive Assessment) from preoperative values to those measures 1 week postsurgery. Secondary outcomes included a battery of neurocognitive tests completed at both 1 week and 3 months postsurgery as well as 30-day postsurgical outcomes.

RESULTS

Forty-three controls and 44 closed-loop patients were assessed for the primary outcome. There was a difference in the cognition score compared to baseline in the control group versus the closed-loop group 1 week postsurgery (-1 [-2 to 0] vs. 0 [-1 to 1]; difference 1 [95% CI, 0 to 3], P = 0.033). Patients in the closed-loop group spent less time during surgery with a Bispectral Index less than 40, had less end-tidal hypocapnia, and had a lower fluid balance compared to the control group.

CONCLUSIONS

Automated anesthetic management using the combination of three controllers outperforms manual control and may have an impact on delayed neurocognitive recovery. However, given the study design, it is not possible to determine the relative contribution of each controller on the cognition score.

The effect of perioperative anesthetics for prevention of postoperative delirium on general anesthesia: A network meta-analysis

STUDY OBJECTIVE

Postoperative delirium (POD) is a common neurological system disorder in surgical patients. Anesthesia providers have a wide choice of sedative agents involving different mechanisms in clinical practice, and the incidence of POD varies regarding which sedative agent administered. This network meta-analysis aimed to comprehensively analyze the safety and efficacy of each choice for patients.

DESIGN

A network meta-analysis.

SETTING

Vanderbilt University Medical Center.

MEASUREMENTS

We searched PubMed, EMBASE, Ovid Medline and Cochrane Central Register of Controlled Trials (CENTRAL) through the end of September 2018 with the registration number CRD42018110585. The randomized controlled trials were identified and extracted by two reviewers independently. Commonly used sedative agents such as placebo, sevoflurane, desflurane, isoflurane, dexmedetomidine, propofol, midazolam, and ketamine were assessed in this network meta-analysis and the primary outcome was the incidence of POD. The data were synthesized by network meta-analysis. Pair-wise meta-analyses were conducted using the random-effects model. Each intervention was ranked according to its corresponding surface under the cumulative ranking curve (SUCRA) values. The GRADE framework was undertaken to evaluate the risk of bias.

MAIN RESULTS

We identified 39 RCTs and 5991 patients in this meta-analysis. Dexmedetomidine was found to be the most effective option in reducing POD, compared to midazolam, propofol, desflurane, and sevoflurane. The results revealed that dexmedetomidine was associated with a lower incidence of POD, whereas midazolam was associated with a significantly higher number of patients with delirium. Midazolam and propofol were also associated with a higher incidence of perioperative hypotension and bradycardia.

CONCLUSION

Our study provided meta-analytic evidence and suggested dexmedetomidine could be considered as the most effective sedative agent to reduce POD. However, clinical practitioners still need to weigh the pros and cons before choosing a sedative agent for individual patient.