Cardiovascular effects of auricular stimulation -a systematic review and meta-analysis of randomized controlled clinical trials.

Background: The number of randomized controlled trials using auricular stimulation (AS) such as transauricular vagus nerve stimulation, or other auricular electrostimulation or auricular acupuncture or acupressure, in experimental and clinical settings, has increased markedly over the last three decades. This systematic review focusses on cardiovascular effects of auricular stimulation. Methods and analysis: The following databases were searched: MEDLINE (PubMed), EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), ISI Web of Science, and Scopus Database. RCTs were reviewed that had been published in English and European languages. Data collection and analysis was conducted by two reviewers independently. Quality and risk assessment of included studies was performed and the meta-analysis of the effect of the most frequently assessed biomarkers. Results: Altogether, 78 trials were included. 38 studies assessed heart rate (HR), 19 studies analyzed heart rate variability (HRV), 31 studies analyzed blood pressure (BP) and 7 studies were identified that measured oxygen saturation (O2), 2 studies on baroreflex sensitivity and 2 studies on skin conductance were evaluated in this review. 26 studies contained continuous data and were eligible for meta-analysis, 50 trials reported non continuous data and were evaluated descriptively. The overall quality of the studies was moderate to low. AS leads to a significant reduction of HR, the changes though were not considered an adverse reaction. Furthermore, when looking at HRV, AS was able to reduce the LF/HF ratio significantly compared to control procedures. No other cardiovascular parameters (blood pressure, oxygen saturation, baroreflex sensitivity) were changed significantly. AS produced only minor side effects in all trials. Conclusion: AS can lead to clinically safe reduction of HR and changes in the LF/HF ratio of the HRV, which is presumably via an increase in vagal activity. More research is needed to clarify whether AS can be used to modulate tachycardia or indications with autonomic imbalance. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=231885 PROSPERO, ID CRD42021231885.

Serum Biomarkers of a Pro-Neuroinflammatory State May Define the Pre-Operative Risk for Postoperative Delirium in Spine Surgery.

Advances in spine surgery enable technically safe interventions in older patients with disabling spine disease, yet postoperative delirium (POD) poses a serious risk for postoperative recovery. This study investigates biomarkers of pro-neuroinflammatory states that may help objectively define the pre-operative risk for POD. This study enrolled patients aged ≥60 scheduled for elective spine surgery under general anesthesia. Biomarkers for a pro-neuroinflammatory state included S100 calcium-binding protein ß (S100ß), brain-derived neurotrophic factor (BDNF), Gasdermin D, and the soluble ectodomain of the triggering receptor expressed on myeloid cells 2 (sTREM2). Postoperative changes of Interleukin-6 (IL-6), Interleukin-1ß (IL-1ß), and C-reactive protein (CRP) were assessed as markers of systemic inflammation preoperatively, intraoperatively, and early postoperatively (up to 48 h). Patients with POD (n = 19, 75.7 ± 5.8 years) had higher pre-operative levels of sTREM2 (128.2 ± 69.4 pg/mL vs. 97.2 ± 52.0 pg/mL, p = 0.049) and Gasdermin D (2.9 ± 1.6 pg/mL vs. 2.1 ± 1.4 pg/mL, p = 0.29) than those without POD (n = 25, 75.6 ± 5.1 years). STREM2 was additionally a predictor for POD (OR = 1.01/(pg/mL) [1.00-1.03], p = 0.05), moderated by IL-6 (Wald-χ2 = 4.06, p = 0.04). Patients with POD additionally showed a significant increase in IL-6, IL-1ß, and S100ß levels on the first postoperative day. This study identified higher levels of sTREM2 and Gasdermin D as potential markers of a pro-neuroinflammatory state that predisposes to the development of POD. Future studies should confirm these results in a larger cohort and determine their potential as an objective biomarker to inform delirium prevention strategies.

Duration of Surgery and Intraoperative Blood Pressure Management Are Modifiable Risk Factors for Postoperative Neurocognitive Disorders After Spine Surgery: Results of the Prospective CONFESS Study.

STUDY DESIGN: Prospective quasi-experimental observational study. OBJECTIVE: The objective of this study was to evaluate whether duration of surgery is a modifiable risk factor for postoperative delirium (POD) after spine surgery and explore further modifiable risk factors. In addition, we sought to investigate the association between POD and postoperative cognitive dysfunction and persistent neurocognitive disorders. SUMMARY OF BACKGROUND DATA: Advances in spine surgery enable technically safe interventions in elderly patients with disabling spine disease. The occurrence of POD and delayed neurocognitive complications ( e.g. postoperative cognitive dysfunction/persistent neurocognitive disorder) remain a concern since these contribute to inferior functional outcomes and long-term care dependency after spine surgery. MATERIALS AND METHODS: This prospective single-center study recruited patients aged 60 years or above and scheduled for elective spine surgery between February 2018 and March 2020. Functional (Barthel Index, BI) and cognitive outcomes [Consortium to Establish a Registry for Alzheimer's Disease (CERAD) test battery; telephone Montréal Cognitive Assessment] were assessed at baseline, three (V3), and 12 months postoperatively. The primary hypothesis was that the duration of surgery predicts POD. Multivariable predictive models of POD included surgical and anesthesiological parameters. RESULTS: Twenty-two percent of patients developed POD (n=22/99). In a multivariable model, duration of surgery [OR adj =1.61/h (95% CI, 1.20-2.30)], age [OR adj =1.22/yr (95% CI, 1.10-1.36)], and baseline deviations of intraoperative systolic blood pressure [25th percentile: OR adj =0.94/mm Hg (95% CI, 0.89-0.99); 90th percentile: OR adj =1.07/mm Hg (95% CI, 1.01-1.14)] were significantly associated with POD. Postoperative cognitive scores generally improved (V3, ΔCERAD total z -score: 0.22±0.63). However, this positive group effect was counteracted by POD [beta: -0.87 (95% CI, -1.31 to 0.42)], older age [beta: -0.03/yr (95% CI, -0.05 to 0.01)], and lack of functional improvement [ΔBI; beta: -0.04/point (95% CI, -0.06 to 0.02)]. Cognitive scores at twelve months remained inferior in the POD group, adjusted for baseline cognition/age. CONCLUSIONS: This study identified distinct neurocognitive effects after spine surgery, which are influenced by perioperative risk factors. Potential cognitive benefits are counteracted by POD, rendering its prevention critical in an aging population.

Tracheal airway pressure in tracheostomy tube capping trials: an experimental study.

BACKGROUND: Tracheostomy tube capping is a commonly used test to determine if the tracheostomy tube can be removed. The success of the capping trial depends on the patient's ability to maintain sufficient spontaneous breathing with an occluded tracheostomy tube. The impact of an occluded tracheotomy tube on airway resistance is currently unknown. The aim of this study was to investigate tracheal pressure during capping or stoma button insertion and potential determinants concerning cuff. METHODS: Eight cuffed and uncuffed tracheostomy tubes and three stoma buttons of various manufacturers and sizes were inserted into the trachea model. Cuffs were completely deflated or contained atmospheric pressure. The trachea was ventilated bidirectional with a respirator in volume-controlled mode and volume flows 15-60 L/min. Tracheal pressure drop during inspiration as a parameter of pressure required to move gas through the airway was measured. RESULTS: Tracheal pressure drops occurred linearly or irregularly during capping trials to a maximum of 4.2 kPa at flow rates of 60 L/min for atmospheric pressure cuffs. In tracheostomy tubes with completely deflated cuffs, pressure drop in the trachea reaches a maximum of 3.4 kPa at a flow rate of 60 L/min. For tracheostomy tubes with cuff smaller inner or outer diameters do not regularly result in lower tracheal pressure drop. The pressure drop varies between different tracheostomy tubes depending on the manufacturer. In cuffed tracheostomy tubes, we observed three phenomena: sail-like positioning, folding over, and tightening of the cuff during flow. The maximum tracheal pressure drop during stoma button insertion reaches 0.014 kPa. CONCLUSIONS: The cuff is a central element for the pressure drop in the airway and thus airway resistance during spontaneous translaryngeal breathing with a capped TT. Complete deflation reduces the pressure drop in the trachea. Due to deformation of the cuff, measured pressures are irregular as the volume flow is increased. Incomplete deflated cuffs and material characteristics of tracheostomy tubes and cuffs in addition to anatomical and clinical variables may cause unsuccessful capping trials due to increased airway resistance. All stoma buttons showed that pressure drop and thus airway resistance due to stoma buttons has no clinical relevance.

Evidence for a modulating effect of transcutaneous auricular vagus nerve stimulation (taVNS) on salivary alpha-amylase as indirect noradrenergic marker: A pooled mega-analysis.

BACKGROUND: Non-invasive transcutaneous auricular vagus nerve stimulation (taVNS) has received tremendous attention as a potential neuromodulator of cognitive and affective functions, which likely exerts its effects via activation of the locus coeruleus-noradrenaline (LC-NA) system. Reliable effects of taVNS on markers of LC-NA system activity, however, have not been demonstrated yet. METHODS: The aim of the present study was to overcome previous limitations by pooling raw data from a large sample of ten taVNS studies (371 healthy participants) that collected salivary alpha-amylase (sAA) as a potential marker of central NA release. RESULTS: While a meta-analytic approach using summary statistics did not yield any significant effects, linear mixed model analyses showed that afferent stimulation of the vagus nerve via taVNS increased sAA levels compared to sham stimulation (b = 0.16, SE = 0.05, p = 0.001). When considering potential confounders of sAA, we further replicated previous findings on the diurnal trajectory of sAA activity. CONCLUSION(S): Vagal activation via taVNS increases sAA release compared to sham stimulation, which likely substantiates the assumption that taVNS triggers NA release. Moreover, our results highlight the benefits of data pooling and data sharing in order to allow stronger conclusions in research.

Stimulation of Lactation Using Acupuncture: A Case Study.

INTRODUCTION: Breastfeeding is a recognized preferred method of infant feeding; however, for many women, difficulties in breastfeeding result in termination before the recommended period of time. Acupuncture is suggested to be a promising option to treat lactation insufficiency and enhance the production of maternal milk. MAIN ISSUE: We have reported the case of a woman with lactation insufficiency due to Caesarean section and congenital unilateral invaginated nipple. Milk production started on the 3rd day following delivery. The newborn was not provided with any food or fluids other than mother's milk. At 5 days of life, the newborn required long feeding periods and lost 4% of his birth weight, with the participant reporting lactation insufficiency described by the perception of inadequate milk production. MANAGEMENT: Despite the implementation of conventional measures to improve lactation, the difficulties in breastfeeding persisted. Acupuncture was tried on Day 6 of life, and enhanced milk production was observed, which could be measured as the volume of residual milk extracted using the breast pump each time after the newborn achieved satiety. After acupuncture treatment there was an augmentation of maternal milk production from both breasts and successful lactation. CONCLUSION: This case study provides information that might be useful for prospective investigation of acupuncture's efficacy in women with lactation insufficiency.

Effectiveness of Acupuncture for Pain Control After Cesarean Delivery: A Randomized Clinical Trial.

IMPORTANCE: A pharmacological approach to pain control after cesarean delivery is often insufficient on its own. Acupuncture is a promising method for mitigating postoperative pain and reducing postoperative opioid requirements. OBJECTIVE: To evaluate the efficacy and effectiveness of acupuncture as an adjunctive therapy for pain control after cesarean delivery, compared with a placebo intervention and standard care alone. DESIGN, SETTING, AND PARTICIPANTS: This single-center, placebo-controlled, patient- and assessor-blinded randomized clinical trial was conducted from January 13, 2015, to June 27, 2018, at a tertiary university hospital in Greifswald, Germany. Participants were women who were scheduled for elective cesarean delivery under spinal anesthesia and were randomized to either the acupuncture group (n = 60) or placebo group (n = 60). Another 60 consecutive patients who met the eligibility criteria and received the standard postoperative analgesia were selected to form a nonrandomized standard care group. The intention-to-treat analysis was performed from August 19, 2019, to September 13, 2019. INTERVENTIONS: In addition to standard pain treatment, each patient in the acupuncture group received auricular and body acupuncture with indwelling intradermal needles, whereas patients in the placebo group were treated with nonpenetrating placebo needles. MAIN OUTCOMES AND MEASURES: The primary outcome was pain intensity on movement, which was measured using an 11-item verbal rating scale. Secondary outcomes were analgesia-related adverse effects, analgesics consumption, time to mobilization and Foley catheter removal, quality of patient blinding to randomization, and patient satisfaction with treatment of pain. RESULTS: A total of 180 female patients (mean [SD] age, 31 [5] years) were included in the intention-to-treat analysis. The mean pain intensity on movement in the acupuncture group on the first postoperative day was lower than in the placebo group (4.7 [1.8] vs 6.0 [2.0] points; Cohen d, 0.73; 95% CI, 0.31-1.01; P = .001) and the standard care group (6.3 [1.3] points; Cohen d, 1.01; 95% CI, 0.63-1.40; P < .001). On the first postoperative day, 59 patients (98%) in the acupuncture group were fully mobilized vs 49 patients (83%) in the placebo group (relative risk [RR], 1.18; 95% CI, 1.06-1.33; P = .01) and 35 patients (58%) in the standard care group (RR, 1.69; 95% CI, 1.36-2.09; P < .001). The Foley catheter was removed in a total of 57 patients (93%) from the acupuncture group vs 43 patients (72%) from the placebo group (RR, 1.33; 95% CI, 1.12-1.57; P = .003) and 42 patients (70%) from the standard care group (RR, 1.37; 95% CI, 1.14-1.62; P = .002). Other parameters were comparable across the 3 study groups. CONCLUSIONS AND RELEVANCE: Results of this trial showed that acupuncture was safe and effective in reducing pain and accelerating mobilization of patients after cesarean delivery. With consideration for personnel and time expenditures, acupuncture can be recommended as routine, supplemental therapy for pain control in patients after elective cesarean delivery. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02364167.

Auricular stimulation for preoperative anxiety - A systematic review and meta-analysis of randomized controlled clinical trials.

STUDY OBJECTIVE: Previous randomized controlled trials (RCTs) suggest that auricular stimulation (AS) is safe and effective in treatment of preoperative anxiety; however, a systematic evaluation is lacking. The aim was to summarize the evidence on efficacy and safety of AS for preoperative anxiety, as well as for other outcomes. DESIGN: We conducted a systematic review of RCTs including patients from all available populations. The search was done through MEDLINE (PubMed), EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), ISI Web of Science and Scopus Database from inception to June 2020. Study selection and data extraction were performed in by 2 independent reviewers with ability to resolve disagreements by a third author. Meta-analyses as well as the risk of bias and evidence quality assessments were performed according to the Cochrane 6.2, 2021 handbook recommendations. INTERVENTIONS: We compared AS with pharmacological and non-pharmacological interventions for different outcomes. MEASUREMENTS: We assessed the repercussion of the evaluated interventions over anxiety scores and their safety, physiological parameters, perioperative medications requirement and intensity of postoperative pain. MAIN RESULTS: We have included 15 studies with 1603 patients. AS has presented reduced anxiety scores as compared to the sham control (Standardized Mean Difference (SMD) -0.72, 95% confidence interval (CI) -1.09 to -0.36, p < 0.0001; 8 trials; 701 patients; heterogeneity: I2 80%; GRADE: moderate certainty) and to no intervention (SMD -1.01, 95% CI -1.58 to -0.45, p = 0.0004; 4 trials; 420 patients; heterogeneity: I2 84%; GRADE: very low certainty). There was no difference between AS and benzodiazepines (SMD -0.03; 95% CI: -0.34 to 0.28; p = 0.84; 3 trials; 158 patients; heterogeneity: I2 0%; GRADE: very low certainty). No trials reported serious adverse effects of AS. CONCLUSIONS: AS may be useful in treatment of preoperative anxiety. Due to heterogenous certainty in effect estimates, further research is needed to clarify the actual efficacy of AS for preoperative anxiety.

Pain perception during injection of local anesthesia in pedodontics.

OBJECTIVE: Few studies have examined pain levels for the injection of local anesthesia in children, though it is a routine technique in pediatric dentistry. The objective of the study was to evaluate the difference in the assessment of procedural pain by the child, parent, dental practitioner, and independent observers during injection of local anesthesia for dental treatment in pediatric dentistry. METHOD AND MATERIALS: In total, 27 male and 22 female children (5 to 17 years of age, mean ± SD 9.8 ± 4.0 years) received local anesthesia (LA) via infiltration or mandibular alveolar blocks according to a standard protocol. After the dental treatment, the children assessed the pain levels for the procedures on a visual analog scale (VAS), while their parents and the dental practitioner used a numeric rating scale (0 to 10). Independent observers also assessed pain via video tape for an evaluation after blinding. The heart rate was monitored continuously during the procedure. The Bland-Altman method was used to quantify the comparison between pain ratings. RESULTS: The assessed level of pain by dental practitioner, parent, and child during injection of LA differed clearly (child: 3.94 ± 2.71; parent: 3.31 ± 2.60; dental practitioner: 3.02 ± 1.98; video observer 1: 1.76 ± 2.56; video observer 2: 1.89 ± 2.55). In 42.9% of cases the dental practitioner's rating and the self--reported pain by the child during injection of LA differed by ≥ 2 on the numeric rating scale, which is clinically a highly different and relevant assessment. CONCLUSION: As pain perception in children during the injection of local anesthetic and its assessment varies considerably depending on the assessing person and the treated child, dental practitioners and researchers should be cautious in interpreting the patient's pain perception.

Safety of percutaneous dilatational tracheotomy (PDT) with the rigid tracheotomy endoscope (TED): a 6-month follow-up multicenter investigation.

BACKGROUND: The rigid tracheotomy endoscope (TED) was recently introduced to improve the fiberoptic technique during percutaneous dilatational tracheotomy (PDT) in critically ill patients. The aim was to evaluate the long-term complications of PDT using TED equipment in a prospective multicenter investigation. METHODS: One hundred eighty adult patients underwent PDT using TED in four German hospitals. Patients who were alive or their guardians were contacted via telephone and interviewed using a structured questionnaire 6 months following the tracheostomy procedure. Patients with airway complaints were invited for outpatient clinical ENT examination. The incidence of adverse events related to PDT was registered. RESULTS: Of 180 patients who received tracheostomy, 137 (76.1%) were alive at the time of follow-up. None of the 43 lethal events was related to the PDT. Fifty-three (38.7%) patients were available for follow-up examination, whereas 14 (10.2%) were able to visit ENT physicians. Two (3.8%) out of 53 patients developed tracheocutaneous fistula with required surgical closure of tracheostoma. Dyspnea (7.5%), hoarseness (5.7%), stridor and swallowing difficulties (both with 3.8%) were the most common complaints. Tracheal stenosis was confirmed in 1 patient (1.88% [95% CI: 0.33; 9.93]). CONCLUSION: The use of TED for PDT in the clinical setting is safe regarding adverse events at 6-month follow-up. The incidence of tracheal stenosis after PDT with TED is comparable with that of flexible bronchoscopy; however, its role for PDT at the intensive care unit should be clarified in further investigations.

Automated Chest Compression Allows Sufficient Resuscitation During Computed Tomography to Reveal the Cause of In-hospital Cardiac Arrest-A Case Report.

Computed tomography (CT) may be used to determine the reversible causes of in-hospital cardiac arrest (IHCA), while the automated chest compression devices (ACCDs) might be helpful to maintain sufficient circulation in x-ray environment during CT. We describe a case, where ACCD was used for continuous cardiopulmonary resuscitation during the CT procedure in an 82-year-old patient with IHCA of unknown cause. Artifact-free CT helped to identify the retroperitoneal hemorrhage as a cause of IHCA, which could not be identified using bedside diagnostics. This observation suggests ACCDs as a helpful adjunct for cardiopulmonary resuscitation in patients undergoing CT diagnostics of IHCA.

Auricular Acupuncture for Preoperative Anxiety-Protocol of Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Background: Preoperative anxiety causes profound psychological and physiological reactions that may lead to a worse postoperative recovery, higher intensity of acute and persistent postsurgical pain and impaired quality of life in the postoperative period. Previous randomized controlled trials (RCTs) suggest that auricular acupuncture (AA) is safe and effective in the treatment of preoperative anxiety; however there is a lack of systematic evidence on this topic. Therefore, this protocol was developed following the PRISMA guidelines to adequately evaluate the existing literature regarding the value of AA for the reduction in anxiety in patients in a preoperative setting, compared to other forms of acupuncture, pharmacological, or no control interventions and measured with questionnaires regarding anxiety and fear. Methods: The following databases will be searched: MEDLINE (PubMed), EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), ISI Web of Science, and Scopus Database. RCTs will be included if an abstract is available in English. Data collection and analysis will be conducted by two reviewers independently. Quality and risk assessment of included studies will be done using the Cochrane 5.1.0 handbook criteria and meta-analysis of effectiveness and symptom scores will be conducted using the statistical software RevMan V.5.3. Conclusions: This systematic review will evaluate the efficacy and safety of AA for preoperative anxiety. Since all data used in this systematic review and meta-analysis have been published, this review does not require ethical approval. The results may be published in a peer-reviewed journal or be presented in relevant conferences. Registration number: PROSPERO ID CRD42020.

Auricular stimulation vs. expressive writing for exam anxiety in medical students - A randomized crossover investigation.

OBJECTIVE: Auricular stimulation (AS) is a promising method in the treatment of situational anxiety. Expressive writing (EW) is an established psychological method, which reduces test anxiety and improves exam results. The aim of this crossover trial was to compare AS with EW, and with the no intervention (NI) condition, for treatment of exam anxiety. METHODS: Healthy medical students underwent 3 comparable anatomy exams with an interval of one month, either performing EW, receiving AS or NI prior to the exam; the order of interventions was randomized. AS was applied using indwelling fixed needles bilaterally at the areas innervated mostly by the auricular branch of the vagal nerve on the day before the exam. Anxiety level, measured using State-Trait-Anxiety Inventory (STAI) before and after the interventions and immediately before exam, was the primary outcome. Quality of night sleep, blood pressure, heart rate and activity of salivary alpha-amylase (sAA) were analyzed across 3 conditions. RESULTS: All 37 included participants completed the study. Anxiety level (STAI) decreased immediately after AS in comparison with baseline (P = 0.02) and remained lower in comparison with that after EW and NI (P<0.01) on the day of exam. After EW and NI anxiety increased on the day of exam in comparison with baseline (P<0.01). Quality of sleep improved after AS in comparison with both control conditions (P<0.01). The activity of sAA decreased after EW and after AS (P<0.05) but not after NI condition. CONCLUSION: Auricular stimulation, but not expressive writing, reduced exam anxiety and improved quality of sleep in medical students. These changes might be due to reduced activity of the sympathetic nervous system.

Acupuncture for Relief of Gag Reflex in Patients Undergoing Transoesophageal Echocardiography-A Protocol for a Randomized Placebo-Controlled Trial.

Background: Gagging during transesophageal echocardiography examination (TEE) can be distressing and even dangerous for patients. The needling of acupuncture point CV24 was described to be effective in reducing the gag reflex during TEE in patients with ischemic stroke or transient ischemic attack. Methods: We describe a proposal for a prospective, randomized, patient, practitioner and assessor-blinded, single-center trial with two arms/groups; real acupuncture will be compared to placebo acupuncture. A total of 60 (30 per group) patients scheduled for elective TEE in order to exclude a cardiac embolic source, endocarditis or for valve failure evaluation will be recruited according to patients' selection criteria and receive either indwelling fixed intradermal needles at acupoints CV24 and bilateral PC6 or placebo needles at the same areas. Patients, the practitioners who will perform the TEE procedure, and the assessor of the outcome measures will be unaware of the group's (real or placebo) allocation. Results: The primary outcome is the intensity of gagging, measured using verbal rating scale (VRS-11) from 0 = no gagging to 10 = intolerable gagging. Secondary outcomes include the incidence of gagging, the use of rescue medication, patients' satisfaction with relief of unwanted side effects during TEE procedure, success of patients' blinding (patients' opinion to group allocation), heart rate and oxygen saturation measured by pulse oxymetry. Conclusions: To study the effects of acupuncture against gagging during TEE, we test the needling of acupoints CV24 and PC6 bilaterally. A placebo acupuncture is used for the control group. Trial registration number: NCT NCT0382142.

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

[This corrects the article DOI: 10.2196/15488.].

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. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/15488.