Changes in Intrinsic Connectivity Networks Topology Across Levels of Dexmedetomidine-Induced Alteration of Consciousness.

BACKGROUND: Human consciousness is generally thought to emerge from the activity of intrinsic connectivity networks (resting-state networks [RSNs]) of the brain, which have topological characteristics including, among others, graph strength and efficiency. So far, most functional brain imaging studies in anesthetized subjects have compared wakefulness and unresponsiveness, a state considered as corresponding to unconsciousness. Sedation and general anesthesia not only produce unconsciousness but also phenomenological states of preserved mental content and perception of the environment (connected consciousness), and preserved mental content but no perception of the environment (disconnected consciousness). Unresponsiveness may be seen during unconsciousness, but also during disconnectedness. Deep dexmedetomidine sedation is frequently a state of disconnected consciousness. In this study, we were interested in characterizing the RSN topology changes across 4 different and steady-state levels of dexmedetomidine-induced alteration of consciousness, namely baseline (Awake, drug-free state), Mild sedation (drowsy, still responding), Deep sedation (unresponsive), and Recovery, with a focus on changes occurring between a connected consciousness state and an unresponsiveness state. METHODS: A functional magnetic resonance imaging database acquired in 14 healthy volunteers receiving dexmedetomidine sedation was analyzed using a method combining independent component analysis and graph theory, specifically looking at changes in connectivity strength and efficiency occurring during the 4 above-mentioned dexmedetomidine-induced altered consciousness states. RESULTS: Dexmedetomidine sedation preserves RSN architecture. Unresponsiveness during dexmedetomidine sedation is mainly characterized by a between-networks graph strength alteration and within-network efficiency alteration of lower-order sensory RSNs, while graph strength and efficiency in higher-order RSNs are relatively preserved. CONCLUSIONS: The differential dexmedetomidine-induced RSN topological changes evidenced in this study may be the signature of inadequate processing of sensory information by lower-order RSNs, and of altered communication between lower-order and higher-order networks, while the latter remain functional. If replicated in an experimental paradigm distinguishing, in unresponsive subjects, disconnected consciousness from unconsciousness, such changes would sustain the hypothesis that disconnected consciousness arises from altered information handling by lower-order sensory networks and altered communication between lower-order and higher-order networks, while the preservation of higher-order networks functioning allows for an internally generated mental content (or dream).

Cardiac Biomarkers and Prediction of Early Outcome After Heart Valve Surgery: A Prospective Observational Study.

OBJECTIVES: Circulating cardiac biomarkers may improve the prediction of long-term outcomes after cardiac surgery. The authors sought to assess if cardiac biomarkers also help better predict short-term morbidity. DESIGN: Prospective observational study. SETTING: Single academic hospital. PARTICIPANTS: A total of 250 patients undergoing aortic or mitral valve surgery with or without associated coronary artery bypass grafts. INTERVENTION: None MEASUREMENT AND MAIN RESULTS: Relationships between preoperative plasma concentrations of four cardiac biomarkers (sST2, Galectin-3, GDF-15, and NT-proBNP) and postoperative outcome were assessed using logistic regressions and Cox proportional hazards models. The primary outcome was a composite of 30-day mortality, an inotropic support longer than 48 hours and an initial length of stay in the intensive care >five days. Secondary outcome measures were postoperative acute kidney injury, inotropic support duration, lengths of intensive care unit and hospital stays, and 30-day and one-year mortality. No association was observed between any of the four cardiac biomarkers and the primary outcome. The preoperative levels of Galectin-3 (hazard ratio = 1.2; p < 0.001) and sST2 (hazard ratio = 1.01, p < 0.001) were significantly associated with one-year survival, and their addition to the EuroSCORE II significantly improved the prediction of one-year mortality (p < 0.001). Similarly, Galectin-3 was associated with postoperative acute kidney injury (odds ratio = 1.15, p = 0.001) and improved the prediction of this complication when added to the EuroSCORE II (p = 0.002). CONCLUSIONS: These results suggested that the ability of cardiac biomarkers to predict short-term outcome after cardiac surgery, though of interest, appears limited. Conversely, cardiac biomarkers may have the potential to refine the prediction of long-term outcome. Admittedly, all positive results were obtained on secondary outcomes and must be regarded with caution.

The spectral exponent of the resting EEG indexes the presence of consciousness during unresponsiveness induced by propofol, xenon, and ketamine.

Despite the absence of responsiveness during anesthesia, conscious experience may persist. However, reliable, easily acquirable and interpretable neurophysiological markers of the presence of consciousness in unresponsive states are still missing. A promising marker is based on the decay-rate of the power spectral density (PSD) of the resting EEG. We acquired resting electroencephalogram (EEG) in three groups of healthy participants (n = 5 each), before and during anesthesia induced by either xenon, propofol or ketamine. Dosage of each anesthetic agent was tailored to yield unresponsiveness (Ramsay score = 6). Delayed subjective reports assessed whether conscious experience was present ('Conscious report') or absent/inaccessible to recall ('No Report'). We estimated the decay of the PSD of the resting EEG-after removing oscillatory peaks-via the spectral exponent ß, for a broad band (1-40 Hz) and narrower sub-bands (1-20 Hz, 20-40 Hz). Within-subject anesthetic changes in ß were assessed. Furthermore, based on ß, 'Conscious report' states were discriminated against 'no report' states. Finally, we evaluated the correlation of the resting spectral exponent with a recently proposed index of consciousness, the Perturbational Complexity Index (PCI), derived from a previous TMS-EEG study. The spectral exponent of the resting EEG discriminated states in which consciousness was present (wakefulness, ketamine) from states where consciousness was reduced or abolished (xenon, propofol). Loss of consciousness substantially decreased the (negative) broad-band spectral exponent in each subject undergoing xenon or propofol anesthesia-indexing an overall steeper PSD decay. Conversely, ketamine displayed an overall PSD decay similar to that of wakefulness-consistent with the preservation of consciousness-yet it showed a flattening of the decay in the high-frequencies (20-40 Hz)-consistent with its specific mechanism of action. The spectral exponent was highly correlated to PCI, corroborating its interpretation as a marker of the presence of consciousness. A steeper PSD of the resting EEG reliably indexed unconsciousness in anesthesia, beyond sheer unresponsiveness.

The Edmonton Frail Scale Improves the Prediction of 30-Day Mortality in Elderly Patients Undergoing Cardiac Surgery: A Prospective Observational Study.

OBJECTIVES: To investigate whether the Edmonton Frail Scale (EFS), a multidimensional frailty assessment tool, improves the prediction of 30-day or in-hospital mortality over the use of the European System for Cardiac Outcome Risk Evaluation (EuroSCORE) II alone. DESIGN: Single-center prospective observational study. SETTING: University hospital. PARTICIPANTS: Patients aged 75 years or older undergoing cardiac surgery between February 2014 and May 2017. INTERVENTION: No intervention was performed. The EFS was administered the day before surgery. MEASUREMENTS AND MAIN RESULTS: The primary endpoint was 30-day or in-hospital mortality. Secondary endpoints were times to discharge from the intensive care unit (ICU) and from the hospital, discharge to a health care facility, and ability to return home by postoperative day 30. The EFS had a good discriminative ability for 30-day mortality (area under the receiver operating characteristic curve = 0.69; 95% confidence interval [CI], 0.56-0.82). Adding frailty, defined by an EFS ≥8, to the EuroSCORE II significantly improved the prediction of 30-day (p = 0.04) mortality. The integrated discrimination index was 0.03 (95% CI, 0.01-0.06, p = 0.01), meaning that the difference in predicted risk between patients who died and those who survived increased by 3% due to the addition of frailty determined by the EFS to the EuroSCORE II. Frailty also was associated significantly with a decreased cumulative probability of discharge from the ICU (p = 0.02) and an increased incidence of discharge to a health care facility (p = 0.01). CONCLUSION: The EFS has a good predictive ability for 30-day mortality after cardiac surgery in elderly patients and improves the prediction of 30-day mortality over the use of the EuroSCORE II.

Low Cardiac Output Syndrome After Adult Cardiac Surgery: Predictive Value of Peak Systolic Global Longitudinal Strain.

BACKGROUND: Peak systolic global longitudinal strain (GLS) is increasingly used to quantify left ventricular systolic function. The primary objective of this study was to assess whether GLS obtained during intraoperative transesophageal echocardiogram, performed before cardiopulmonary bypass, improves the prediction of postoperative low cardiac output syndrome (LCOS) after adult cardiac surgery. METHODS: GLS from 275 patients undergoing on-pump cardiac surgery was calculated retrospectively using two-dimensional- speckle tracking echocardiography (aCMQ module from Qlab software version 10.5, Philips Medical, Brussels, Belgium). LCOS was defined as the need for inotropic or mechanical circulatory support for >24 hours postoperatively. Patient and procedure characteristics associated with LCOS at the univariable level (P ≤ .05) were entered into a forward stepwise logistic regression to create a first predictive model. A second model was created by adding GLS. The 2 models were compared using the likelihood-ratio test, the area under the receiver operating characteristic (ROC) curve, and the integrated discrimination index. The optimal cutoff value of GLS associated with LCOS was determined by maximizing the Youden index of the ROC curve. Secondary outcomes included time until complete weaning from inotropes, discharge from the intensive care unit and from the hospital, and 30-day mortality. RESULTS: GLS was significantly associated with LCOS (P < .001) at the univariable level. Predictors of LCOS retained in the first model were cardiopulmonary bypass duration, decreased left ventricular ejection fraction, mitral valve surgery, and New York Heart Association functional class III or IV. Adding the GLS value improved the prediction of LCOS (P = .02). However, the area under the ROC curve did not differ between the 2 models (0.83; 95% confidence interval [CI], 0.77-0.99 vs 0.84; 95% CI, 0.79-0.90; P = .15). The integrated discrimination index associated with addition of GLS was 0.02 (P = .046), meaning that the difference in predicted risk between patients with and without LCOS increased by 2% after adding GLS. A GLS cutoff value of -17% (95% CI, -18.8% to -15.3%) was found to best identify LCOS. After adjusting for covariates included in model 1, a lower GLS value was significantly associated with a lower cumulative probability of weaning from inotropes postoperatively (hazard ratio, 0.90; 95% CI, 0.82-0.97; P = .01). No association was found between GLS and other secondary outcome measures. CONCLUSIONS: GLS is an independent predictor of LCOS after on-pump cardiac surgery. Its incremental value over other established risk factors for postoperative LCOS is, however, limited.

Sedation of Patients With Disorders of Consciousness During Neuroimaging: Effects on Resting State Functional Brain Connectivity.

BACKGROUND: To reduce head movement during resting state functional magnetic resonance imaging, post-coma patients with disorders of consciousness (DOC) are frequently sedated with propofol. However, little is known about the effects of this sedation on the brain connectivity patterns in the damaged brain essential for differential diagnosis. In this study, we aimed to assess these effects. METHODS: Using resting state functional magnetic resonance imaging 3T data obtained over several years of scanning patients for diagnostic and research purposes, we employed a seed-based approach to examine resting state connectivity in higher-order (default mode, bilateral external control, and salience) and lower-order (auditory, sensorimotor, and visual) resting state networks and connectivity with the thalamus, in 20 healthy unsedated controls, 8 unsedated patients with DOC, and 8 patients with DOC sedated with propofol. The DOC groups were matched for age at onset, etiology, time spent in DOC, diagnosis, standardized behavioral assessment scores, movement intensities, and pattern of structural brain injury (as assessed with T1-based voxel-based morphometry). RESULTS: DOC were associated with severely impaired resting state network connectivity in all but the visual network. Thalamic connectivity to higher-order network regions was also reduced. Propofol administration to patients was associated with minor further decreases in thalamic and insular connectivity. CONCLUSIONS: Our findings indicate that connectivity decreases associated with propofol sedation, involving the thalamus and insula, are relatively small compared with those already caused by DOC-associated structural brain injury. Nonetheless, given the known importance of the thalamus in brain arousal, its disruption could well reflect the diminished movement obtained in these patients. However, more research is needed on this topic to fully address the research question.

Quality of life at home and satisfaction of patients after enhanced recovery protocol for colorectal surgery.

BACKGROUND: Quality of life of patients at home after an enhanced recovery protocol (ERP) for surgery has been least studied especially in elderly patients. METHODS: Our first 41 patients entered in the colorectal GRACE database were interviewed through telephone about their postoperative stress, fatigue, pain, difficulty in feeding, home autonomy, and satisfaction. We compared the responses of the elderly patients (>70 years, n = 19) with those of the younger patients. RESULTS: The time between the surgery and the questionnaire was 79 ± 48 days. Early return was experienced as stressful by ±20% of the patients. Fatigue and pain were low (respectively: simple numerical scale [SNS] = 4.2 ± 3.2 and 2.5 ± 2.9). When present, pain was relieved by the prescribed treatment. One-third of the patients described some difficulty in feeding. Fifty percent of the patients felt completely autonomous when returned at home, 80% attributed the rapid recovery of autonomy to the ERP. Finally, 87% were globally satisfied (SNS: 8.5 ± 1.0). The characteristics of the 'elderly' group (77 ± 6 years) and their questionnaire responses were similar to those of the younger patients. CONCLUSIONS: Despite some limitations (retrospective, different time between surgery and the telephone survey), our study suggests that quality of life at home after ERP for colorectal surgery is very satisfactory for over 80% of patients. Furthermore, this study confirms that elderly patients benefit from an ERP for colorectal surgery like younger patients.

Resting-state Network-specific Breakdown of Functional Connectivity during Ketamine Alteration of Consciousness in Volunteers.

BACKGROUND: Consciousness-altering anesthetic agents disturb connectivity between brain regions composing the resting-state consciousness networks (RSNs). The default mode network (DMn), executive control network, salience network (SALn), auditory network, sensorimotor network (SMn), and visual network sustain mentation. Ketamine modifies consciousness differently from other agents, producing psychedelic dreaming and no apparent interaction with the environment. The authors used functional magnetic resonance imaging to explore ketamine-induced changes in RSNs connectivity. METHODS: Fourteen healthy volunteers received stepwise intravenous infusions of ketamine up to loss of responsiveness. Because of agitation, data from six subjects were excluded from analysis. RSNs connectivity was compared between absence of ketamine (wake state [W1]), light ketamine sedation, and ketamine-induced unresponsiveness (deep sedation [S2]). RESULTS: Increasing the depth of ketamine sedation from W1 to S2 altered DMn and SALn connectivity and suppressed the anticorrelated activity between DMn and other brain regions. During S2, DMn connectivity, particularly between the medial prefrontal cortex and the remaining network (effect size ß [95% CI]: W1 = 0.20 [0.18 to 0.22]; S2 = 0.07 [0.04 to 0.09]), and DMn anticorrelated activity (e.g., right sensory cortex: W1 = -0.07 [-0.09 to -0.04]; S2 = 0.04 [0.01 to 0.06]) were broken down. SALn connectivity was nonuniformly suppressed (e.g., left parietal operculum: W1 = 0.08 [0.06 to 0.09]; S2 = 0.05 [0.02 to 0.07]). Executive control networks, auditory network, SMn, and visual network were minimally affected. CONCLUSIONS: Ketamine induces specific changes in connectivity within and between RSNs. Breakdown of frontoparietal DMn connectivity and DMn anticorrelation and sensory and SMn connectivity preservation are common to ketamine and propofol-induced alterations of consciousness.

Development and Validation of a Morphologic Obstructive Sleep Apnea Prediction Score: The DES-OSA Score.

BACKGROUND: Obstructive sleep apnea (OSA) is a common and underdiagnosed entity that favors perioperative morbidity. Several anatomical characteristics predispose to OSA. We developed a new clinical score that would detect OSA based on the patient's morphologic characteristics only. METHODS: Patients (n = 149) scheduled for an overnight polysomnography were included. Their morphologic metrics were compared, and combinations of them were tested for their ability to predict at least mild, moderate-to-severe, or severe OSA, as defined by an apnea-hypopnea index (AHI) >5, >15, or >30 events/h. This ability was calculated using Cohen κ coefficient and prediction probability. RESULTS: The score with best prediction abilities (DES-OSA score) considered 5 variables: Mallampati score, distance between the thyroid and the chin, body mass index, neck circumference, and sex. Those variables were weighted by 1, 2, or 3 points. DES-OSA score >5, 6, and 7 were associated with increased probability of an AHI >5, >15, or >30 events/h, respectively, and those thresholds had the best Cohen κ coefficient, sensitivities, and specificities. Receiver operating characteristic curve analysis revealed that the area under the curve was 0.832 (95% confidence interval [CI], 0.762-0.902), 0.805 (95% CI, 0.734-0.876), and 0.834 (95% CI, 0.757-0.911) for DES-OSA at predicting an AHI >5, >15, and >30 events/h, respectively. With the aforementioned thresholds, corresponding sensitivities (95% CI) were 82.7% (74.5-88.7), 77.1% (66.9-84.9), and 75% (61.0-85.1), and specificities (95% CI) were 72.4% (54.0-85.4), 73.2% (60.3-83.1), and 76.9% (67.2-84.4). Validation of DES-OSA performance in an independent sample yielded highly similar results. CONCLUSIONS: DES-OSA is a simple score for detecting OSA patients. Its originality relies on its morphologic nature. Derived from a European population, it may prove useful in a preoperative setting, but it has still to be compared with other screening tools in a general surgical population and in other ethnic groups.

Distribution of Injectate and Sensory-Motor Blockade After Adductor Canal Block.

BACKGROUND: The analgesic efficacy reported for the adductor canal block may be related to the spread of local anesthetic outside the adductor canal. METHODS: Fifteen patients undergoing knee surgery received ultrasound-guided injections of local anesthetic at the level of the adductor hiatus. Sensory-motor block and spread of contrast solution were assessed. RESULTS: Sensation was rated as "markedly diminished" or "absent" in the saphenous nerve distribution and "slightly diminished" in the sciatic nerve territory without motor deficits. Contrast solution was found in the popliteal fossa. CONCLUSIONS: The spread of injectate to the popliteal fossa may contribute to the analgesic efficacy of adductor canal block.

Interfascial Spread of Injectate After Adductor Canal Injection in Fresh Human Cadavers.

The adductor canal block has become a common analgesic technique in patients undergoing knee arthroplasty. Dispersion of local anesthetic outside the adductor canal through interfascial layers and blockade of smaller nerves that confer innervation to the knee could contribute to the analgesic efficacy of the adductor canal block. We studied the diffusion of local anesthetic mixed with dye after injection into the adductor canal in fresh human cadavers. In all 8 legs, injectate was found in the popliteal fossa in contact with the sciatic nerve and/or popliteal blood vessels. Interfascial spread patterns were identified.

Prevalence, characteristics and risk factors of chronic postsurgical pain after laparoscopic colorectal surgery: Retrospective analysis.

BACKGROUND: The prevalence of chronic postsurgical pain (CPSP) is a critical medical problem with economic implications. Its prevalence after gastrointestinal surgery is not well documented, particularly when a laparoscopic approach is used. OBJECTIVE: The aim of the study was to determine the prevalence, the characteristics and the risk factors for CPSP after laparoscopic colorectal surgery. DESIGN: A retrospective analysis using a postal questionnaire. SETTING: The study was conducted at a university teaching hospital. PATIENTS: Patients who underwent laparoscopic colorectal surgery from April 2008 until December 2011 (n = 260). No epidural analgesia was used. MAIN OUTCOME MEASURES: Postoperative pain intensity, incidence and characteristics of CPSP, and impact on quality of life and sleep. RESULTS: Of 199 responses, 33 patients (17%) reported chronic pain at a median [interquartile range, IQR] of 38 [27 to 55] months after laparoscopic surgery with a median intensity of 4 [3 to 5]. CPSP had a negative impact on the quality of life in 84% of patients and on sleep in 43%. CPSP required regular analgesic(s) intake in 54% patients. Using a backward stepwise multivariate logistic regression model, the following variables were determined as independent risk factors for CPSP: redo surgery for anastomotic leakage (P = 0.01), inflammatory bowel disease (IBD) as the indication for surgery (P = 0.01) and preoperative pain (P = 0.05). CONCLUSION: The incidence of CPSP after laparoscopic colorectal surgery (17%) is similar to those reported in the literature after laparotomy. Risk factors are redo surgery for postoperative peritonitis, IBD and preoperative pain. TRIAL REGISTRATION: EudraCT 2012-005712-25.

Connectivity changes underlying spectral EEG changes during propofol-induced loss of consciousness.

The mechanisms underlying anesthesia-induced loss of consciousness remain a matter of debate. Recent electrophysiological reports suggest that while initial propofol infusion provokes an increase in fast rhythms (from beta to gamma range), slow activity (from delta to alpha range) rises selectively during loss of consciousness. Dynamic causal modeling was used to investigate the neural mechanisms mediating these changes in spectral power in humans. We analyzed source-reconstructed data from frontal and parietal cortices during normal wakefulness, propofol-induced mild sedation, and loss of consciousness. Bayesian model selection revealed that the best model for explaining spectral changes across the three states involved changes in corticothalamic interactions. Compared with wakefulness, mild sedation was accounted for by an increase in thalamic excitability, which did not further increase during loss of consciousness. In contrast, loss of consciousness per se was accompanied by a decrease in backward corticocortical connectivity from frontal to parietal cortices, while thalamocortical connectivity remained unchanged. These results emphasize the importance of recurrent corticocortical communication in the maintenance of consciousness and suggest a direct effect of propofol on cortical dynamics.

The effects of intrathecal morphine on urinary bladder function and recovery in patients having a cesarean delivery - A randomized clinical trial.

INTRODUCTION: Spinal anesthesia with intrathecal morphine (ITM) is a common anesthesia technique for cesarean delivery. The hypothesis was that the addition of ITM will delay micturition in women undergoing cesarean delivery. METHODS: Fifty-six ASA physical status I and II women scheduled to undergo elective cesarean delivery under spinal anesthesia were randomized to the PSM group (50 mg prilocaine + 2.5 mcg sufentanil + 100 mcg morphine; n = 30) or PS group (50 mg prilocaine + 2.5 mcg sufentanil; n = 24). The patients in the PS group received a bilateral transverse abdominal plane (TAP) block. The primary outcome was the effect of ITM on the time to micturition and the secondary outcome was the need for bladder re-catheterization. RESULTS: The time to first urge to urinate (8 [6-10] hours in the PSM group versus 6 [4-6] hours in the PS group) and the time to first micturition (10 [8-12] hours in the PSM group versus 6 [6-8] hours in the PS group) were significantly (p < 0.001) prolonged in the PSM group. Two patients in the PSM group met the 800 mL criterium for urinary catheterization after 6 and 8 h respectively. CONCLUSION: This study is the first randomized trial to demonstrate that the addition of ITM to the standardized mixture of prilocaine and sufentanil significantly delayed micturition.

Default network connectivity reflects the level of consciousness in non-communicative brain-damaged patients.

The 'default network' is defined as a set of areas, encompassing posterior-cingulate/precuneus, anterior cingulate/mesiofrontal cortex and temporo-parietal junctions, that show more activity at rest than during attention-demanding tasks. Recent studies have shown that it is possible to reliably identify this network in the absence of any task, by resting state functional magnetic resonance imaging connectivity analyses in healthy volunteers. However, the functional significance of these spontaneous brain activity fluctuations remains unclear. The aim of this study was to test if the integrity of this resting-state connectivity pattern in the default network would differ in different pathological alterations of consciousness. Fourteen non-communicative brain-damaged patients and 14 healthy controls participated in the study. Connectivity was investigated using probabilistic independent component analysis, and an automated template-matching component selection approach. Connectivity in all default network areas was found to be negatively correlated with the degree of clinical consciousness impairment, ranging from healthy controls and locked-in syndrome to minimally conscious, vegetative then coma patients. Furthermore, precuneus connectivity was found to be significantly stronger in minimally conscious patients as compared with unconscious patients. Locked-in syndrome patient's default network connectivity was not significantly different from controls. Our results show that default network connectivity is decreased in severely brain-damaged patients, in proportion to their degree of consciousness impairment. Future prospective studies in a larger patient population are needed in order to evaluate the prognostic value of the presented methodology.

Influence of anesthesia on cerebral blood flow, cerebral metabolic rate, and brain functional connectivity.

PURPOSE OF REVIEW: To describe recent studies exploring brain function under the influence of hypnotic anesthetic agents, and their implications on the understanding of consciousness physiology and anesthesia-induced alteration of consciousness. RECENT FINDINGS: Cerebral cortex is the primary target of the hypnotic effect of anesthetic agents, and higher-order association areas are more sensitive to this effect than lower-order processing regions. Increasing concentration of anesthetic agents progressively attenuates connectivity in the consciousness networks, while connectivity in lower-order sensory and motor networks is preserved. Alteration of thalamic sub-cortical regulation could compromise the cortical integration of information despite preserved thalamic activation by external stimuli. At concentrations producing unresponsiveness, the activity of consciousness networks becomes anticorrelated with thalamic activity, while connectivity in lower-order sensory networks persists, although with cross-modal interaction alterations. SUMMARY: Accumulating evidence suggests that hypnotic anesthetic agents disrupt large-scale cerebral connectivity. This would result in an inability of the brain to generate and integrate information, while external sensory information is still processed at a lower order of complexity.

In situ simulation improves perceived self-efficacy of OR nurses and anaesthesiologists during COVID-19 pandemic.

Introduction: Self-efficacy is defined as people's internal beliefs about their ability to have an impact on events that affect their lives. As part of the COVID-19 pandemic, we carried out in situ simulation for anaesthesiologists and operating room (OR) nurses. Simulation was focused on the recommendations on the use of specific personal protective equipment (PPE) as well as on airway management and intubation. We hypothesised that in situ procedural simulation should increase their perceived self-efficacy. Methods: Between 16 March and 20 March 2020, 208 healthcare workers took part in in situ procedural simulation. A questionnaire was sent to participants on 21 April 2020. Six self-efficacy items related to PPE and airway manoeuvres were assessed before and after training on a Numeric Rating Scale from 0 to 10. Results: Sixty-seven participants (32%) replied to the questionnaire. The before-after comparison of the six items revealed an increase in perceived self-efficacy for each of them. A before training difference was observed between nurses, board-certified anaesthetists and trainees in anaesthesia in perceived self-efficacy for putting on (6 (3-8) vs 4.5 (2.25-6) vs 2 (0-6), p=0.007) and remove PPE (8 (5-8) vs 4.5 (3.25-6) vs 4 (1-6), p=0.009). No difference in perceived self-efficacy after training was observed between nurses, board-certified anaesthetists and trainees in anaesthesia. Conclusions: In situ simulation improves the perceived self-efficacy of OR nurses and anaesthesiologists on specific skills related to the care of patients with COVID-19.