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1.
Exp Physiol ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38590228

RESUMO

Transfer function analysis (TFA) is a widely used method for assessing dynamic cerebral autoregulation in humans. In the present study, we assessed the test-retest reliability of established TFA metrics derived from spontaneous blood pressure oscillations and based on 5 min recordings. The TFA-based gain, phase and coherence in the low-frequency range (0.07-0.20 Hz) from 19 healthy volunteers, 37 patients with subarachnoid haemorrhage and 19 patients with sepsis were included. Reliability assessments included the smallest real difference (SRD) and the coefficient of variance for comparing consecutive 5 min recordings, temporally separated 5 min recordings and consecutive recordings with a minimal length of 10 min. In healthy volunteers, temporally separating the 5 min recordings led to a 0.38 (0.01-0.79) cm s-1 mmHg-1 higher SRD for gain (P = 0.032), and extending the duration of recordings did not affect the reliability. In subarachnoid haemorrhage, temporal separation led to a 0.85 (-0.13 to 1.93) cm s-1 mmHg-1 higher SRD (P = 0.047) and a 20 (-2 to 41)% higher coefficient of variance (P = 0.038) for gain, but neither metric was affected by extending the recording duration. In sepsis, temporal separation increased the SRD for phase by 94 (23-160)° (P = 0.006) but was unaffected by extending the recording. A recording duration of 8 min was required to achieve stable gain and normalized gain measures in healthy individuals, and even longer recordings were required in patients. In conclusion, a recording duration of 5 min appears insufficient for obtaining stable and reliable TFA metrics when based on spontaneous blood pressure oscillations, particularly in critically ill patients with subarachnoid haemorrhage and sepsis.

2.
Neurocrit Care ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605221

RESUMO

BACKGROUND: Identifying covert consciousness in intensive care unit (ICU) patients with coma and other disorders of consciousness (DoC) is crucial for treatment decisions, but sensitive low-cost bedside markers are missing. We investigated whether automated pupillometry combined with passive and active cognitive paradigms can detect residual consciousness in ICU patients with DoC. METHODS: We prospectively enrolled clinically low-response or unresponsive patients with traumatic or nontraumatic DoC from ICUs of a tertiary referral center. Age-matched and sex-matched healthy volunteers served as controls. Patients were categorized into clinically unresponsive (coma or unresponsive wakefulness syndrome) or clinically low-responsive (minimally conscious state or better). Using automated pupillometry, we recorded pupillary dilation to passive (visual and auditory stimuli) and active (mental arithmetic) cognitive paradigms, with task-specific success criteria (e.g., ≥ 3 of 5 pupillary dilations on five consecutive mental arithmetic tasks). RESULTS: We obtained 699 pupillometry recordings at 178 time points from 91 ICU patients with brain injury (mean age 60 ± 13.8 years, 31% women, and 49.5% nontraumatic brain injuries). Recordings were also obtained from 26 matched controls (59 ± 14.8 years, 38% women). Passive paradigms yielded limited distinctions between patients and controls. However, active paradigms enabled discrimination between different states of consciousness. With mental arithmetic of moderate complexity, ≥ 3 pupillary dilations were seen in 17.8% of clinically unresponsive patients and 50.0% of clinically low-responsive patients (odds ratio 4.56, 95% confidence interval 2.09-10.10; p < 0.001). In comparison, 76.9% healthy controls responded with ≥ 3 pupillary dilations (p = 0.028). Results remained consistent across sensitivity analyses using different thresholds for success. Spearman's rank analysis underscored the robust association between pupillary dilations during mental arithmetic and consciousness levels (rho = 1, p = 0.017). Notably, one behaviorally unresponsive patient demonstrated persistent command-following behavior 2 weeks before overt signs of awareness, suggesting prolonged cognitive motor dissociation. CONCLUSIONS: Automated pupillometry combined with mental arithmetic can identify cognitive efforts, and hence covert consciousness, in ICU patients with acute DoC.

4.
Acta Neurochir (Wien) ; 166(1): 128, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38462573

RESUMO

BACKGROUND: Ventriculostomy-associated infection (VAI) is common after external ventricular drains (EVD) insertion but is difficult to diagnose in patients with acute brain injury. Previously, we proposed a set of criteria for ruling out VAI in traumatic brain injury. This study aimed to validate these criteria. For exploratory purposes, we sought to develop and validate a score for VAI risk assessment in patients with different types of severe acute brain injury. METHODS: This retrospective cohort study included adults with acute brain injury who received an EVD and in whom CSF samples were taken over a period of 57 months. As standard non-coated bolt-connected EVDs were used. The predictive performance of biomarkers was analyzed as defined previously. A multivariable regression model was performed with five variables. RESULTS: A total of 683 patients with acute brain injury underwent EVD placement and had 1272 CSF samples; 92 (13.5%) patients were categorized as culture-positive VAI, 130 (19%) as culture-negative VAI, and 461 (67.5%) as no VAI. A low CSF WBC/RBC ratio (< 0.037), high CSF/plasma glucose ratio (> 0.6), and low CSF protein (< 0.5g/L) showed a positive predictive value of 0.09 (95%CI, 0.05-0.13). In the multivariable logistic regression model, days to sample (OR 1.09; 95%CI, 1.03-1.16) and CSF WBC/RBC ratio (OR 34.86; 95%CI, 3.94-683.15) were found to predict VAI. CONCLUSION: In patients with acute brain injury and an EVD, our proposed combined cut-off for ruling out VAI performed satisfactorily. Days to sample and CSF WBC/RBC ratio were found independent predictors for VAI in the multivariable logistic regression model.


Assuntos
Lesões Encefálicas , Ventriculostomia , Adulto , Humanos , Ventriculostomia/efeitos adversos , Estudos Retrospectivos , Drenagem/efeitos adversos , Valor Preditivo dos Testes
5.
Basic Clin Pharmacol Toxicol ; 134(5): 676-685, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38504615

RESUMO

The objective of this study was to develop a population pharmacokinetic-pharmacodynamic model of subcutaneously administered bupivacaine in a novel extended-release microparticle formulation for postoperative pain management. Bupivacaine was administered subcutaneously in the lower leg to 28 healthy male subjects in doses from 150 to 600 mg in a phase 1 randomized, placebo-controlled, double-blind, dose-ascending study with two different microparticle formulations, LIQ865A and LIQ865B. Warmth detection threshold was used as a surrogate pharmacodynamic endpoint. Population pharmacokinetic-pharmacodynamic models were fitted to plasma concentration-effect-time data using non-linear mixed-effects modelling. The pharmacokinetics were best described by a two-compartment model with biphasic absorption as two parallel absorption processes: a fast, zero-order process and a slower, first-order process with two transit compartments. The slow absorption process was found to be dose-dependent and rate-limiting for elimination at higher doses. Apparent bupivacaine clearance and the transit rate constant describing the slow absorption process both appeared to decrease with increasing doses following a power function with a shared covariate effect. The pharmacokinetic-pharmacodynamic relationship between plasma concentrations and effect was best described by a linear function. This model gives new insight into the pharmacokinetics and pharmacodynamics of microparticle formulations of bupivacaine and the biphasic absorption seen for several local anaesthetics.


Assuntos
Bupivacaína , Modelos Biológicos , Humanos , Masculino , Bupivacaína/farmacologia , Método Duplo-Cego
6.
Basic Clin Pharmacol Toxicol ; 134(5): 657-675, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38482995

RESUMO

A novel microparticle-based extended-release local anaesthetic containing a bupivacaine/poly-lactic-co-glycolic acid (PLGA; LIQ865A) or plain bupivacaine (LIQ865B) was examined in a first-in-human trial. The objectives were to examine the dose safety/tolerability and pharmacodynamics. Randomized subcutaneous injections of LIQ865A (n = 16) or LIQ865B (n = 12) and diluent, contralaterally, were administered in a dose-ascending manner (150- to 600-mg bupivacaine). Subjects were admitted 24 h post-injection and followed for 30 days post-injection. The risk ratios (RRs; 95% CI) of erythematous reactions for LIQ865A versus diluent was 9.00 (1.81-52.23; P = 0.006) and for LIQ865B versus diluent 2.50 (0.69-9.94; P = 0.37). The RR for the development of hematomas (LIQ865A versus diluent) were 3.25 (1.52-8.16; P = 0.004) and 4.00 (0.72-24.89; P = 0.32) (LIQ865B versus diluent). Subcutaneous indurations persisting for 4-13 weeks were seen in 6/16 subjects receiving LIQ865A. One subject receiving LIQ865A (600-mg bupivacaine) developed intermittent central nervous system (CNS) symptoms of local anaesthetic systemic toxicity (85 min to 51 h post-injection) coinciding with plasma peak bupivacaine concentrations (490-533 ng/ml). Both LIQ865 formulations demonstrated dose-dependent hypoesthesia and hypoalgesia. The duration of analgesia ranged between 37 and 86 h. The overall number of local adverse events, however, prohibits clinical application without further pharmacological modifications.


Assuntos
Analgesia , Bupivacaína , Humanos , Masculino , Bupivacaína/efeitos adversos , Anestésicos Locais/efeitos adversos , Injeções Subcutâneas , Área Sob a Curva , Preparações de Ação Retardada
7.
Exp Physiol ; 109(4): 614-623, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38376110

RESUMO

The mean flow index-usually referred to as Mx-has been used for assessing dynamic cerebral autoregulation (dCA) for almost 30 years. However, concerns have arisen regarding methodological consistency, construct and criterion validity, and test-retest reliability. Methodological nuances, such as choice of input (cerebral perfusion pressure, invasive or non-invasive arterial pressure), pre-processing approach and artefact handling, significantly influence mean flow index values, and previous studies correlating mean flow index with other established dCA metrics are confounded by inherent methodological flaws like heteroscedasticity, while the mean flow index also fails to discriminate individuals with presumed intact versus impaired dCA (discriminatory validity), and its prognostic performance (predictive validity) across various conditions remains inconsistent. The test-retest reliability, both within and between days, is generally poor. At present, no single approach for data collection or pre-processing has proven superior for obtaining the mean flow index, and caution is advised in the further use of mean flow index-based measures for assessing dCA, as current evidence does not support their clinical application.


Assuntos
Pressão Arterial , Circulação Cerebrovascular , Humanos , Reprodutibilidade dos Testes , Homeostase/fisiologia , Circulação Cerebrovascular/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Ultrassonografia Doppler Transcraniana , Pressão Sanguínea/fisiologia
8.
Acta Neurochir (Wien) ; 166(1): 63, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315234

RESUMO

PURPOSE: Intensive care for patients with traumatic brain injury (TBI) aims, among other tasks, at avoiding high intracranial pressure (ICP), which is perceived to worsen motor and cognitive deficits and increase mortality. International recommendations for threshold values for ICP were increased from 20 to 22 mmHg in 2016 following the findings in a study by Sorrentino et al., which were based on an observational study of patients with TBI of averaged ICP values. We aimed to reproduce their approach and validate the findings in a separate cohort. METHODS: Three hundred thirty-one patients with TBI were included and categorised according to survival/death and favourable/unfavourable outcome at 6 months (based on Glasgow Outcome Score-Extended of 6-8 and 1-5, respectively). Repeated chi-square tests of survival and death (or favourable and unfavourable outcome) vs. high and low ICP were conducted with discrimination between high and low ICP sets at increasing values (integers) between 10 and 35 mmHg, using the average ICP for the entire monitoring period. The ICP limit returning the highest chi-square score was assumed to be the threshold with best discriminative ability. This approach was repeated after stratification by sex, age, and initial Glasgow Coma Score (GCS). RESULTS: An ICP limit of 18 mmHg was found for both mortality and unfavourable outcome for the entire cohort. The female and the low GCS subgroups both had threshold values of 18 mmHg; for all other subgroups, the threshold varied between 16 and 30 mmHg. According to a multiple logistic regression analysis, age, initial GCS, and average ICP are independently associated with mortality and outcome. CONCLUSIONS: Using identical methods and closely comparable cohorts, the critical thresholds for ICP found in the study by Sorrentino et al. could not be reproduced.


Assuntos
Lesões Encefálicas Traumáticas , Pressão Intracraniana , Humanos , Feminino , Lesões Encefálicas Traumáticas/diagnóstico , Lesões Encefálicas Traumáticas/terapia , Cuidados Críticos , Monitorização Fisiológica/métodos
9.
Infect Dis (Lond) ; 56(5): 402-409, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38339990

RESUMO

BACKGROUND: Carbapenems are widely used for empiric treatment of healthcare-associated central nervous system (CNS) infections. We investigated the feasibility of a carbapenem-sparing strategy, utilising a third-generation cephalosporin (ceftriaxone or cefotaxime) (combined with vancomycin) for the empirical treatment of healthcare-associated CNS infections in Eastern Denmark. METHODS: The departments of neurosurgery and neuro-intensive care at Copenhagen University Hospital Rigshospitalet. First, we analysed local microbiological data (1st January 2020-31st August 2022) to identify microorganisms non-susceptible to third-generation cephalosporin. Subsequently, we assessed all carbapenem prescriptions over a three-month period for their indication and justification. RESULTS: In total, 25,247 bacterial cultures were identified, of which 2,563 CNS-related, were included in the analysis. The positivity rate was 10.5% (n = 257/2439) for cerebrospinal-fluid samples and 75.8% (n = 95/124) for brain parenchyma. CNS samples from five individual patients revealed bacteria non-susceptible to third generation cephalosporins (Enterobacter spp. (n = 3), Pseudomonas spp. (n = 2), Klebsiella spp. (n = 2), Citrobacter freundii (n = 1)). All five patients had been hospitalised for ≥10days at the time-point of antibiotic therapy. Out of 11,626 sets of blood cultures, a total of 10 individual patients had Gram-negative blood-stream infections with resistance to ceftriaxone and piperacillin/tazobactam. 140 days-of-therapy (32%) with carbapenem in 18 patients (36%) were definitively or possibly indicated according to guidelines, none were indicated for healthcare-associated CNS-infections. CONCLUSION: An empiric treatment strategy relying on a third-generation cephalosporin appears suitable for healthcare-associated CNS infections at our tertiary hospital, serving a population of 2.6 million. However, in patients with prolonged hospitalization (≥10 days), immunosuppression, prior broad-spectrum antibiotic use, or history of resistant Gram-negative bacteria, empirical prescription of carbapenem may be needed.


Assuntos
Infecções do Sistema Nervoso Central , Infecção Hospitalar , Humanos , Carbapenêmicos/uso terapêutico , Ceftriaxona , Antibacterianos/uso terapêutico , Infecção Hospitalar/tratamento farmacológico , Atenção à Saúde , Sistema Nervoso Central , Infecções do Sistema Nervoso Central/tratamento farmacológico , Dinamarca
10.
Acta Neurochir (Wien) ; 166(1): 24, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38240848

RESUMO

BACKGROUND: No standard has been established regarding timing and choice of strategy for discontinuation of external ventricular drainage (EVD) in patients with aneurysmal subarachnoid haemorrhage (aSAH), and little is known about the importance of clinical variables. A proportion of the patients who initially pass their discontinuation attempt return with delayed hydrocephalus and the need of a permanent shunt. Early differentiation between patients who need a shunt and those who do not would facilitate care. We conducted a retrospective analysis on patients with aSAH and an EVD to search significant differences in treatment and clinical variables between patients who received a permanent shunt during initial hospitalization or after readmission, and those who never received a shunt. METHODS: We included 183 patients with aSAH who received an EVD over a 4-year period between 2015 and 2018 and divided them into three groups: those who received a shunt during primary admission, those who were readmitted for delayed hydrocephalus and received a shunt, and those who never needed a shunt. Between these groups, we compared selected clinical variables as well as outcome at discharge and after 6 months. Additionally, we assessed the ability of a shunt dependency score (SDASH) to predict the need for permanent drainage in the patients. RESULTS: Of 183 included patients, 108 (59%) ultimately received a ventriculoperitoneal (VP) shunt. Of these, 89 (82%) failed discontinuation during the primary admission and received a permanent shunt before discharge from the neurosurgical department. The remaining 19 (18%) were discharged after successful discontinuation, but subsequently developed delayed hydrocephalus and were admitted for shunt placement a median of 39 (range: 18-235) days after ictus. Ninety-four patients were discharged after successful discontinuation of the EVD, consisting of those who never developed the need for a permanent shunt and the 19 who were readmitted with delayed hydrocephalus, corresponding to a 20% (19/94) readmittance rate. Clinical variables such as drainage volume or discontinuation strategy did not differ across the three groups of patients. The SDASH score failed to provide any clinically useful information regarding prediction of shunt placement. CONCLUSION: In this study, clinical variables including use of the predictive score SDASH predicted neither the overall need for nor the timing of shunt placement after aSAH. The homogeneous distribution of data between the three different groups renders strong independent clinical predictive factors unlikely. Thus, attempts to predict a permanent shunt requirement from these variables may be futile in these patients.


Assuntos
Hidrocefalia , Hemorragia Subaracnóidea , Humanos , Hidrocefalia/etiologia , Hidrocefalia/cirurgia , Estudos Retrospectivos , Hemorragia Subaracnóidea/cirurgia , Derivação Ventriculoperitoneal
11.
BMJ Neurol Open ; 6(1): e000584, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38268756

RESUMO

Introduction: Acute brain injury can lead to states of decreased consciousness, that is, disorder of consciousness (DoC). Detecting signs of consciousness early is vital for DoC management in the intensive care unit (ICU), neurorehabilitation and long-term prognosis. Our primary objective is to investigate the potential of pharmacological stimulant therapies in eliciting signs of consciousness among unresponsive or low-responsive acute DoC patients. Methods: In a placebo-controlled, randomised, cross-over setting, we evaluate the effect of methylphenidate and apomorphine in 50 DoC patients with acute traumatic or non-traumatic brain injury admitted to the ICU. Patients are examined before and after administration of the trial drugs using (1) neurobehavioural scales to determine the clinical level of consciousness, (2) automated pupillometry to record pupillary responses as a signature for awareness and (3) near-infrared spectroscopy combined with electroencephalography to record neurovascular coupling as a measure for cortical activity. Primary outcomes include pupillary dilations and increase in cortical activity during passive and active paradigms. Ethics: The study has been approved by the ethics committee (Journal-nr: H-21022096) and follows the principles of the Declaration of Helsinki. It is deemed to pose minimal risks and to hold a significant potential to improve treatment options for DoC patients. If the stimulants are shown to enhance cortical modulation of pupillary function and neurovascular coupling, this would warrant a large multicentre trial to evaluate their clinical impact. Dissemination: Results will be available on EudraCT, clinicaltrialsregister.eu and published in an international peer-reviewed journal. Trial registration number: EudraCT Number: 2021-001453-31.

12.
Acta Anaesthesiol Scand ; 68(2): 188-194, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37877464

RESUMO

BACKGROUND: The reliability of near-infrared spectroscopy (NIRS) for measuring cerebral oxygenation (ScO2 ) is controversial due to the possible contamination from extracranial tissues. We compared ScO2 measured with the NIRS optode on the forehead, the skull and the dura mater in anaesthetised patients undergoing craniotomy. We hypothesised that ScO2 measured directly on the skull and the dura mater would differ from ScO2 measured on the skin. METHODS: This prospective observational study included 17 adult patients scheduled for elective craniotomy. After induction of general anaesthesia, ScO2 was measured on the forehead skin, as well as on the skull and on the dura mater in the surgical field. The primary comparison was the difference in ScO2 measured on the dura mater and on ScO2 measured on the skin; secondary comparisons were the differences in ScO2 on the skull and ScO2 on the skin and the dura mater, respectively. Data were described with median (5%-95% range) and analysed with the Wilcoxon signed-rank test. RESULTS: ScO2 values on the dura mater were obtained in 11 patients, and median ScO2 (48%, 29%-95%) did not differ significantly from ScO2 on the skin (73%, 49%-92%; p = .052), median difference -25% (-35.6% to -1.2%). ScO2 on the skull (N = 16) was lower than that on the skin (63% [43%-79%] vs. 75% [61%-94%]; p = .0002), median difference -10% (-20.8 to -3.0). CONCLUSION: In adults undergoing craniotomy, NIRS-based ScO2 measured on the dura mater did not reach statistically significantly lower values than ScO2 measured on the skin, whereas values on the skull were lower than on the skin, indicating a contribution from scalp tissue to the signal.


Assuntos
Oxigênio , Espectroscopia de Luz Próxima ao Infravermelho , Adulto , Humanos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Reprodutibilidade dos Testes , Encéfalo , Crânio , Dura-Máter
13.
Ugeskr Laeger ; 185(51)2023 12 18.
Artigo em Dinamarquês | MEDLINE | ID: mdl-38105735

RESUMO

Acute bacterial meningitis (ABM) is associated with increased intracranial pressure (ICP) caused by bacterial invasion and the host response to infection. Antibiotic therapy is a sine qua non, and adjunct dexamethasone decreases mortality. The ICP increase may have a rapid course and death due to herniation is most often seen within the first week. Evidence regarding treatment of increased ICP in ABM is limited; this review summarises observational studies which point towards reduced mortality by applying a structured approach towards normalization of ICP in ABM.


Assuntos
Hipertensão Intracraniana , Meningites Bacterianas , Humanos , Pressão Intracraniana , Meningites Bacterianas/tratamento farmacológico , Antibacterianos/uso terapêutico , Hipertensão Intracraniana/tratamento farmacológico , Hipertensão Intracraniana/etiologia
14.
Eur J Anaesthesiol ; 40(12): 946-950, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37909157

RESUMO

An expressed and constant wish of the first author's oldest daughter to enhance interaction with her favourite toy animal led to a (re)animation/resuscitation attempt of a 1½-year-old stuffed plush bunny. Initial physical examination found no vital signs. Based on the lack of identifiable airways, we hypothesised that tissue oxygenation might be caused by passive diffusion throughout the body. Hence, animation was attempted by mechanical chest compressions without including airway management or positive-pressure ventilation. Multimodal monitoring of arterial blood pressure (by proxy), intra-'cranial' pressure and oxygen tension, near-infrared spectroscopy of the head and laser-Doppler blood flow was successfully initiated, whereas an attempt at intracranial microdialysis was unsuccessful. Despite achieving measurable arterial blood pressure (by proxy) (12/3 mmHg) and an increase of cerebral perfusion by 30 points, spontaneous circulation or diffusion was not achieved apparently, and ultimately, animation attempts were ceased. Clinical experience, as well as common sense, forces us to conclude that our measurements were contaminated by the intervention, and that we must rethink the method for the animation of stuffed plush bunnies.


Assuntos
Hemodinâmica , Respiração com Pressão Positiva , Circulação Cerebrovascular
15.
Ugeskr Laeger ; 185(43)2023 Oct 23.
Artigo em Dinamarquês | MEDLINE | ID: mdl-37921107

RESUMO

Tick-borne encephalitis (TBE) is a viral tick-borne infection occurring in many parts of Europe and Asia as described in this review. Increasing TBE case numbers have been reported over recent decades. In Denmark the infection is rare (1-14 annual cases). The rise in TBE in Denmark is mainly driven by microfoci outside of Bornholm, primarily North Zealand. Clinical illness has a bi-phasic presentation: "summer-flu" which may be followed by a neuroinfection. No specific treatment exists, and mortality is less-than 1%. A considerable percentage of patients may experience neurological sequelae. TBE is preventable through vaccination.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Encefalite Transmitida por Carrapatos , Humanos , Encefalite Transmitida por Carrapatos/diagnóstico , Encefalite Transmitida por Carrapatos/epidemiologia , Encefalite Transmitida por Carrapatos/prevenção & controle , Europa (Continente) , Estações do Ano , Vacinação
16.
Mol Psychiatry ; 28(10): 4272-4279, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37814129

RESUMO

Selective serotonin reuptake inhibitors (SSRIs) are widely used for treating neuropsychiatric disorders. However, the exact mechanism of action and why effects can take several weeks to manifest is not clear. The hypothesis of neuroplasticity is supported by preclinical studies, but the evidence in humans is limited. Here, we investigate the effects of the SSRI escitalopram on presynaptic density as a proxy for synaptic plasticity. In a double-blind placebo-controlled study (NCT04239339), 32 healthy participants with no history of psychiatric or cognitive disorders were randomized to receive daily oral dosing of either 20 mg escitalopram (n = 17) or a placebo (n = 15). After an intervention period of 3-5 weeks, participants underwent a [11C]UCB-J PET scan (29 with full arterial input function) to quantify synaptic vesicle glycoprotein 2A (SV2A) density in the hippocampus and the neocortex. Whereas we find no statistically significant group difference in SV2A binding after an average of 29 (range: 24-38) days of intervention, our secondary analyses show a time-dependent effect of escitalopram on cerebral SV2A binding with positive associations between [11C]UCB-J binding and duration of escitalopram intervention. Our findings suggest that brain synaptic plasticity evolves over 3-5 weeks in healthy humans following daily intake of escitalopram. This is the first in vivo evidence to support the hypothesis of neuroplasticity as a mechanism of action for SSRIs in humans and it offers a plausible biological explanation for the delayed treatment response commonly observed in patients treated with SSRIs. While replication is warranted, these results have important implications for the design of future clinical studies investigating the neurobiological effects of SSRIs.


Assuntos
Disfunção Cognitiva , Inibidores Seletivos de Recaptação de Serotonina , Humanos , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Escitalopram , Encéfalo , Sinapses , Disfunção Cognitiva/tratamento farmacológico , Citalopram/farmacologia , Citalopram/uso terapêutico
17.
Front Physiol ; 14: 1213352, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37731542

RESUMO

In humans, resting cerebral perfusion, oxygen consumption and energy metabolism demonstrate large intersubject variation regardless of methodology. Whether a similar large variation is also present longitudinally in individual subjects is much less studied, but knowing the time variance in reproducibility is important when designing and interpreting longitudinal follow-up studies examining brain physiology. Therefore, we examined the reproducibility of cerebral blood flow (CBF), global cerebral metabolic rate of oxygen (CMRO2), global arteriovenous oxygen saturation difference (A-V.O2), and cerebral lactate and N-acetyl-aspartate (NAA) concentrations measured using magnetic resonance imaging (MRI) and spectroscopy (MRS) techniques through repeated measurements at 6 h, 24 h, 7 days and several weeks after initial baseline measurements in young healthy adults (N = 26, 13 females, age range 18-35 years). Using this setup, we calculated the correlation, limit of agreement (LoA) and within-subject coefficient of variation (CoVWS) between baseline values and the subsequent repeated measurements to examine the longitudinal variation in individual cerebral physiology. CBF and CMRO2 correlated significantly between baseline and all subsequent measurements. The strength of the correlations (R2) and reproducibility metrics (LoA and CoVWS) demonstrated the best reproducibility for the within-day measurements and generally declined with longer time between measurements. Cerebral lactate and NAA concentrations also correlated significantly for all measurements, except between baseline and the 7-day measurement for lactate. Similar to CBF and CMRO2, lactate and NAA demonstrated the best reproducibility for within-day repeated measurements. The gradual decline in reproducibility over time should be considered when designing and interpreting studies on brain physiology, for example, in the evaluation of treatment efficacy.

18.
Artigo em Inglês | MEDLINE | ID: mdl-37740814

RESUMO

Personalizing psychotherapy can be challenging within standardized group Cognitive Behavioral Therapy (CBT), in which sessions are structured according to a protocol and must accommodate the needs and preferences of multiple patients. In the current study, we aimed to examine patients' and therapists' experiences of standardized group CBT and identify their perceptions of different patient needs. Furthermore, we explored how these needs can inform possible content of add-on interventions for patients who are not improving as expected during group CBT.We conducted 21 individual in-depth interviews with patients with depression and their therapists about their experiences during group CBT with Routine Outcome Monitoring (ROM) and feedback. Interviews were analyzed by using a hermeneutic-phenomenological thematic analysis. Five themes, representing different patient needs, were identified: (1) Individual attention, (2) Psychological exploration, (3) A focus on the patient's life outside of therapy, (4) Extended assessment, and (5) Agreement on therapeutic tasks.The study supports that "one size does not fit all" when it comes to psychotherapy. Patients have varying needs when they are not making progress in therapy, and these needs, when unmet, can negatively impact the overall experience of group CBT. By acknowledging the unique needs of each patient and providing additional individual sessions as necessary, we can move towards a more personalized approach that maximizes the benefits of group psychotherapy.

19.
Neurocrit Care ; 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37697124

RESUMO

BACKGROUND: In intensive care unit (ICU) patients with coma and other disorders of consciousness (DoC), outcome prediction is key to decision-making regarding prognostication, neurorehabilitation, and management of family expectations. Current prediction algorithms are largely based on chronic DoC, whereas multimodal data from acute DoC are scarce. Therefore, the Consciousness in Neurocritical Care Cohort Study Using Electroencephalography and Functional Magnetic Resonance Imaging (i.e. CONNECT-ME; ClinicalTrials.gov identifier: NCT02644265) investigates ICU patients with acute DoC due to traumatic and nontraumatic brain injuries, using electroencephalography (EEG) (resting-state and passive paradigms), functional magnetic resonance imaging (fMRI) (resting-state) and systematic clinical examinations. METHODS: We previously presented results for a subset of patients (n = 87) concerning prediction of consciousness levels in the ICU. Now we report 3- and 12-month outcomes in an extended cohort (n = 123). Favorable outcome was defined as a modified Rankin Scale score ≤ 3, a cerebral performance category score ≤ 2, and a Glasgow Outcome Scale Extended score ≥ 4. EEG features included visual grading, automated spectral categorization, and support vector machine consciousness classifier. fMRI features included functional connectivity measures from six resting-state networks. Random forest and support vector machine were applied to EEG and fMRI features to predict outcomes. Here, random forest results are presented as areas under the curve (AUC) of receiver operating characteristic curves or accuracy. Cox proportional regression with in-hospital death as a competing risk was used to assess independent clinical predictors of time to favorable outcome. RESULTS: Between April 2016 and July 2021, we enrolled 123 patients (mean age 51 years, 42% women). Of 82 (66%) ICU survivors, 3- and 12-month outcomes were available for 79 (96%) and 77 (94%), respectively. EEG features predicted both 3-month (AUC 0.79 [95% confidence interval (CI) 0.77-0.82]) and 12-month (AUC 0.74 [95% CI 0.71-0.77]) outcomes. fMRI features appeared to predict 3-month outcome (accuracy 0.69-0.78) both alone and when combined with some EEG features (accuracies 0.73-0.84) but not 12-month outcome (larger sample sizes needed). Independent clinical predictors of time to favorable outcome were younger age (hazard ratio [HR] 1.04 [95% CI 1.02-1.06]), traumatic brain injury (HR 1.94 [95% CI 1.04-3.61]), command-following abilities at admission (HR 2.70 [95% CI 1.40-5.23]), initial brain imaging without severe pathological findings (HR 2.42 [95% CI 1.12-5.22]), improving consciousness in the ICU (HR 5.76 [95% CI 2.41-15.51]), and favorable visual-graded EEG (HR 2.47 [95% CI 1.46-4.19]). CONCLUSIONS: Our results indicate that EEG and fMRI features and readily available clinical data predict short-term outcome of patients with acute DoC and that EEG also predicts 12-month outcome after ICU discharge.

20.
Fluids Barriers CNS ; 20(1): 49, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37353833

RESUMO

BACKGROUND: It is crucial to maintain the intracranial pressure (ICP) within the physiological range to ensure proper brain function. The ICP may fluctuate during the light-dark phase cycle, complicating diagnosis and treatment choice in patients with pressure-related disorders. Such ICP fluctuations may originate in circadian or sleep-wake cycle-mediated modulation of cerebrospinal fluid (CSF) flow dynamics, which in addition could support diurnal regulation of brain waste clearance. METHODS: ICP was monitored continuously in patients who underwent placement of an external ventricular drain (EVD) and by telemetric monitoring in experimental rats. CSF was collected via the EVD in patients and the rodent CSF secretion rate determined by in vivo experimentation. Rodent choroid plexus transporter transcripts were quantified with RNAseq and transport activity with ex vivo isotope transport assays. RESULTS: We demonstrated that ICP increases by 30% in the dark phase in both species, independently of vascular parameters. This increase aligns with elevated CSF collection in patients (12%) and CSF production rate in rats (20%), the latter obtained with the ventriculo-cisternal perfusion assay. The dark-phase increase in CSF secretion in rats was, in part, assigned to increased transport activity of the choroid plexus Na+,K+,2Cl- cotransporter (NKCC1), which is implicated in CSF secretion by this tissue. CONCLUSION: CSF secretion, and thus ICP, increases in the dark phase in humans and rats, irrespective of their diurnal/nocturnal activity preference, in part due to altered choroid plexus transport activity in the rat. Our findings suggest that CSF dynamics are modulated by the circadian rhythm, rather than merely sleep itself.


Assuntos
Plexo Corióideo , Pressão Intracraniana , Humanos , Ratos , Animais , Pressão Intracraniana/fisiologia , Plexo Corióideo/fisiologia , Encéfalo , Proteínas de Membrana Transportadoras , Líquido Cefalorraquidiano
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