Open clavicle fractures: patterns of trauma and associated injuries.

Objectives: To describe the demographic distribution, mechanism of injury, and associated injuries of patients sustaining open clavicle fractures.

Design: Retrospective case series.

Setting: Level I trauma center.

Anterior shoulder instability: a review of pathoanatomy, diagnosis and treatment.

The glenohumeral joint is inherently predisposed to instability by its bony architecture. The incidence of traumatic shoulder instability is 1.7% in the general population.

Scalp EEG acquisition in a low-noise environment: a quantitative assessment.

This pilot study investigates effects of an ultra shielded capsule at the low-noise underground laboratory (LSBB), Rustrel, France, when used to acquire scalp electroencephalogram (EEG). Analysis of EEG recordings from three volunteers confirms that clean EEG signals can be acquired in the LSBB capsule without the need for notch filtering. In addition, using different setups for acquiring EEG in the capsule, statistical analysis of power spectral densities based on a geodesic distance measure reveals that the laptop computer and patient module do not introduce any noise on recorded signals.

Two-stage vs mixed-effect approach to pharmacodynamic modeling of propofol in children using state entropy.

Objectives: To compare the population pharmacodynamic (PD) models of propofol in children derived using two-stage and mixed-effect modeling approaches.

Methods: Fifty-two ASA 1 and 2 children aged 6-15 years presenting for gastrointestinal endoscopy were administered a loading dose of 4 mg·kg(-1) of propofol intravenously at an infusion rate determined by a randomization schedule. Using the plasma concentration predicted by the Paedfusor pharmacokinetic (PK) model, the propofol effect on state entropy (SE) was modeled using the two-stage and the mixed-effect modeling approaches, and the final population PD models were compared with each other in terms of their prediction performance, using median percentage and absolute percentage errors as well as mean absolute weighted error as metrics.

Model-based human circadian phase estimation using a particle filter.

We present a method for tracking an individual's circadian phase that integrates dynamic models of circadian physiology with physiological measurements in a Bayesian statistical framework. A model of the circadian pacemaker's response to light exposure is transformed into a nonlinear state-space model with a circadian phase state. The probability distribution of the circadian phase is estimated by a particle filter that predicts changes over time based on the model, and performs updates with information gained from physiological measurements.

Dynamic behavior of BIS, M-entropy and neuroSENSE brain function monitors.

Objectives: The objective of this paper is to assess the suitability of brain function monitors for use in closed-loop anesthesia or sedation delivery. In such systems, monitors used as feedback sensors should preferably be Linear and Time Invariant (LTI) in order to limit sensor-induced uncertainty which can cause degraded performance. In this paper, we evaluate the suitability of the BIS A2000 (Aspect Medical Systems, MA), the M-Entropy Monitor (GE HealthCare), and the NeuroSENSE Monitor (NeuroWave Systems Inc, OH), by verifying whether their dynamic behavior conforms to the LTI hypothesis.

Robust closed-loop control of propofol administration using WAVCNS index as the controlled variable.

This paper presents a robust closed-loop strategy for control of depth of hypnosis. The proposed method regulates the electroencephalogram (EEG)-derived WAVCNS index as a hypnosis measure by manipulating intravenous propofol administration. In contrast to many existing closed-loop methods, the control design presented in this paper produces stability and robustness against uncertainty by explicitly accounting for the pharmacokinetic (PK) and pharmacodynamic (PD) variability between different individuals, as well as unpredictable surgical stimuli that the closed-loop control is required to tolerate.

Predicting temporal lobe epileptic seizures based on zero-crossing interval analysis in scalp EEG.

A novel real-time patient-specific algorithm to predict epileptic seizures is proposed. The method is based on the analysis of the positive zero-crossing intervals in the scalp electroencephalogram (EEG), describing the brain dynamics. In a moving-window analysis, the histogram of these intervals in each EEG epoch is computed, and the distribution of the histogram value in specific bins, selected using interictal and preictal references, is estimated based on the values obtained from the current epoch and the epochs of the last 5 min.

Monitor-decoupled pharmacodymamics of propofol in children using State Entropy as the clinical end point.

This paper presents two alternative approaches to characterize the pharmacodynamics of propofol anesthesia in children, using State Entropy as a clinical end point. The first approach is the traditional approach where the pharmacodynamic model is described in terms of an effect-site equilibration rate constant and the Hill equation. In the second approach (the monitor-decoupled approach) the dynamics of the Entropy monitor is identified and added to the traditional pharmacodynamic model.

Wavelet based motion artifact removal for Functional Near Infrared Spectroscopy.

Functional Near Infrared Spectroscopy (fNIRS) enables researchers to conduct studies in situations where use of other functional imaging methods is impossible. An important shortcoming of fNIRS is the sensitivity to motion artifacts. We propose a new wavelet based algorithm for removing movement artifacts from fNIRS signals.

An empirical model of end-tidal CO(2) response to minute ventilation.

This paper presents an empirical model of end-tidal CO(2) (P(ET)CO(2)) response to minute ventilation (MV) for use in the closed-loop control of artificial respiration. An affine model structure consisting of a linear dynamic system followed by an affine transform is presented. It is proposed that this derives a low-order, high-fidelity representation of the respiratory process that can describe the positive and inversely proportional relationship between P(ET)CO(2) and MV.

Acute effects of MDMA (3,4-methylenedioxymethamphetamine) on EEG oscillations: alone and in combination with ethanol or THC (delta-9-tetrahydrocannabinol).

Rationale: Typical users of 3,4-methylenedioxymethamphetamine (MDMA or "ecstasy") are polydrug users, combining MDMA with alcohol or cannabis [most active compound: delta-9-tetrahydrocannabinol (THC)].

Objectives: The aim of the present study was to investigate whether co-administration of alcohol or THC with MDMA differentially affects ongoing electroencephalogram (EEG) oscillations compared to the administration of each drug alone.

Methods: In two separate experiments, 16 volunteers received four different drug conditions: (1) MDMA (100 mg); (2) alcohol clamp (blood alcohol concentration = 0.

Slower administration of propofol preserves adequate respiration in children.

Background: Propofol is a versatile anesthetic agent used in pediatric practice to facilitate investigational and interventional procedures. Propofol can cause significant respiratory depression, the management of which may require advanced airway management skills. This investigation aimed to increase the safety of propofol administration by developing a dosing schedule that would preserve spontaneous respiration in at least 95% of subjects.

Closed-loop anesthetic drug concentration estimation using clinical-effect feedback.

This letter presents a novel closed-loop approach to anesthetic drug concentration estimation using clinical-effect measurement feedback. Compared with the open-loop prediction used in current target-controlled infusion systems, closed-loop estimation exploits the discrepancy between the measured and predicted clinical effects to make corrections to the drug-concentration estimate, achieving improved robustness against variability in the patient pharmacokinetics and pharmacodynamics. A robust estimator, which processes drug administration and clinical-effect measurements to estimate the plasma- and effect-site drug concentrations, is designed using μ-synthesis theory.

Acute psychomotor, memory and subjective effects of MDMA and THC co-administration over time in healthy volunteers.

In Western societies a considerable percentage of young people expose themselves to the combination of 3,4-methylenedioxymethamphetamine (MDMA or 'ecstasy') and cannabis. The aim of the present study was to assess the acute effects of co-administration of MDMA and THC (the main psychoactive compound of cannabis) on pharmacokinetics, psychomotor performance, memory and subjective experience over time. We performed a four-way, double blind, randomized, crossover, placebo-controlled study in 16 healthy volunteers (12 male, four female) between the ages of 18 and 27.

Automated real-time epileptic seizure detection in scalp EEG recordings using an algorithm based on wavelet packet transform.

A novel wavelet-based algorithm for real-time detection of epileptic seizures using scalp EEG is proposed. In a moving-window analysis, the EEG from each channel is decomposed by wavelet packet transform. Using wavelet coefficients from seizure and nonseizure references, a patient-specific measure is developed to quantify the separation between seizure and nonseizure states for the frequency range of 1-30 Hz.

A Cusum-based multilevel alerting method for physiological monitoring.

Alerting systems used by current physiological monitors are designed to detect changes in the levels of vital signs, but they tend to be very sensitive to artifacts. This paper proposes a method to detect changes in the direction of trend and generate multilevel alerts according to the statistical significance of the detection. One-point-ahead signal predictions are calculated by averaging the historical data with the weights decreasing in the past.

The effect of a target controlled infusion of propofol on predictability of recovery from anesthesia in children.

Background: Emergence following termination of a general anesthetic depends on the effect site concentration (C(e)) of the drug declining to an awakening value (C(e)-awake). C(e)-awake has been described in adults, but is unknown in children.

Objectives: To determine C(e)-awake in children following a target-controlled infusion (TCI) of propofol and to assess a C(e)-driven TCI system's ability to predict times to emergence from anesthesia.

An entropy-based approach to predict seizures in temporal lobe epilepsy using scalp EEG.

We describe a novel algorithm for the prediction of epileptic seizures using scalp EEG. The method is based on the analysis of the positive zero-crossing interval series of the EEG signal and its first and second derivatives as a measure of brain dynamics. In a moving-window analysis, we estimated the probability density of these intervals and computed the differential entropy.

Assessment of the validity of the frequently used lipid indices for predicting LDL peak particle diameter in a large cohort of 1955 normal and dyslipidemic subjects.

Objectives: To assess the relationship between commonly used lipid indices and LDL peak particle diameter (LDL-PPD) in a large cohort of 1955 subjects.

Design And Methods: Four statistical methods were used for comparison: correlation, concordance analysis, kappa statistics and receiver operating characteristic curve (ROC) analysis.

Results: Plasma triglyceride (TG) levels, TG/HDL-C, LDL-C/apoB, total cholesterol (TC)/TG, LDL-C/TG, and TG/apoB ratios were best correlated with LDL-PPD but none of these ratios accounted for more than 45% of the variation in LDL-PPD.

Endovascular treatment of immature, dysfunctional and thrombosed forearm autogenous ulnar-basilic and radial-basilic fistulas for haemodialysis.

Background: Forearm basilic fistulas are rarely used as vascular accesses for haemodialysis but they represent a valuable option when autogenous radial-cephalic fistulas cannot be performed. There is no information in the literature to date about the outcome of direct ulnar-basilic or transposed radial-basilic forearm autogenous fistulas after endovascular treatment of stenosis or thrombosis.

Methods: This retrospective study included 78 consecutive patients from eight dialysis units who were referred to a single interventional radiology centre for endovascular treatment of delayed maturation (n = 30), dysfunction (n = 35) or thrombosis (n = 13) of their autogenous forearm ulnar-basilic (n = 62) or radial-basilic fistulas (n = 16).

[National external quality assessment in auto-immunity: antineutrophil cytoplasmic antibodies].

The French Health Products Safety Agency organized in 2007, for the scheme of the national external quality assessment, a survey on antineutrophil cytoplasmic antibodies (ANCA) including detection and identification of the antibodies. This survey allowed to assess the quality of the different methods of these assays. The detection of ANCA by the indirect immunofluorescence technique was satisfactory.

Increased oxytocin concentrations and prosocial feelings in humans after ecstasy (3,4-methylenedioxymethamphetamine) administration.

MDMA (3,4-methylenedioxymethamphetamine or "ecstasy") is a recreationally used drug with remarkable and characteristic prosocial effects. In spite of abundant attention in the scientific literature, the mechanism of its prosocial effects has not been elucidated in humans. Recently, research in animals has suggested that the neuropeptide oxytocin may induce these effects.

Cannabis coadministration potentiates the effects of "ecstasy" on heart rate and temperature in humans.

This study assessed the acute physiologic effects over time of (co)administration of Delta9-tetrahydrocannabinol (Delta9-THC) (the main psychoactive compound of cannabis) and 3,4-methylenedioxymethamphetamine (MDMA or "ecstasy") in 16 healthy volunteers. Pharmacokinetics and cardiovascular, temperature, and catecholamine responses were assessed over time. Both single-drug conditions robustly increased heart rate, and coadministration showed additive effects.