Parasomnias and sleep-related movement disorders induced by drugs in the adult population: a review about iatrogenic medication effects.

Parasomnias and sleep-related movement disorders (SRMD) are major causes of sleep disorders and may be drug induced. The objective of this study was to conduct a systematic review of the literature to examine the association between drug use and the occurrence of parasomnias and SRMD. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for reporting systematic reviews, we searched PubMed databases between January 2020 and June 2023. The searches retrieved 937 records, of which 174 publications were selected for full-text screening and 73 drugs were identified. The most common drug-induced parasomnias were nightmares and rapid eye movement (REM) sleep behaviour disorders and sleepwalking. In terms of drug-induced SRMD, restless legs syndrome, periodic limb movement disorders (PLMD), and sleep-related bruxism were most frequent. Medications that inhibit noradrenergic, serotonergic, or orexin transmission could induce REM sleep (e.g., nightmares). Regarding sleepwalking, dysregulation of serotoninergic neurone activity is implicated. Antipsychotics are mentioned, as well as medications involved in the gamma-aminobutyric acid (GABA) pathway. A mechanism of desensitisation-autoregulation of GABA receptors on serotoninergic neurones is a hypothesis. SRMD and PLMD could involve medications disrupting the dopamine pathway (e.g., antipsychotics or opioids). Opioids would act on mu receptors and increase dopamine release. The role of adenosine and iron is also hypothesised. Regarding bruxism, the hypotheses raised involve dysregulation of mesocortical pathway or a downregulation of nigrostriatal pathway, related to medications involving dopamine or serotonin. Parasomnias are rarely identified in drug product labels, likely due to the recent classification of their diagnoses. An analysis of pharmacovigilance data could be valuable to supplement existing literature data.

Radio telemetry devices to monitor breathing in non-sedated animals.

Radio telemetry equipment has significantly improved over the last 10-15 years and is increasingly being used in research for monitoring a variety of physiological parameters in non-sedated animals. The aim of this review is to provide an update on the current state of development of radio telemetry for recording respiration. Our literature review found only rare reports of respiratory studies via radio telemetry. Much of this article will hence report our experience with our custom-built radio telemetry devices designed for recording respiratory signals, together with numerous other physiological signals in lambs. Our current radio telemetry system allows to record 24 simultaneous signals 24h/day for several days. To our knowledge, this is the highest number of physiological signals, which can be recorded wirelessly. Our devices have been invaluable for studying respiration in our ovine models of preterm birth, reflux laryngitis, postnatal exposure to cigarette smoke, respiratory syncytial virus infection and nasal ventilation, all of which are relevant to neonatal respiratory problems.

Microscope spectrometer for light scattering investigations.

We describe a setup including a microscope to study volumes of a few mum(3) by static and dynamic light scattering (DLS) in a backscattering configuration. Light scattered by individual objects of micrometric size can be analyzed in the 400-800?nm spectral range. This setup can also be employed to study both diluted and concentrated colloidal solutions by DLS measurements. For diluted solutions we found evidence of the fluctuations of the number of particles in a confocal volume. We discuss their contribution to the autocorrelation function of the scattered intensity measured as a function of time.

Monitoring pulse oximetry via radiotelemetry in freely-moving lambs.

This study was aimed at validating the use of a custom-made wireless pulse oximeter in freely moving lambs, using radiotelemetry transmission. First, measurements obtained simultaneously using the new, wireless oximeter and a standard commercially-available pulse oximeter (Nonin 8500) were compared in five lambs during 5min episodes of normoxia, hypoxia and hyperoxia. Correlation between the two oximeters for both SpO(2) and heart rate was very good, regardless of oxygenation conditions. Secondly, the capabilities of our device were assessed during more than 45h of polysomnographic recordings in seven lambs. According to the plethysmographic pulse waveform, reliable SpO(2) values were obtained in more than 85% of recording time. Multiple decreases in SpO(2) were readily observed after spontaneous apneas in preterm lambs. It is concluded that our wireless pulse oximeter performs as reliably as a standard pulse oximeter for monitoring SpO(2) variations in lambs, and offers new perspectives for researchers interested in continuous monitoring of oxygenation throughout sleep stages and wakefulness.