Medication administration error prevention among nurses working in intensive care units: A secondary analysis.

BACKGROUND: The intensive care unit (ICU) brings together high-risk patients and interventions in a complex environment. Based on this consideration, medication administration error is the most common type of error that occurs in ICUs. Literature confirms that human factors (lack of knowledge, poor practices and negative attitudes) of nurses are the main contributors to the occurrence of medication administration errors in ICUs. AIM: To examine and compare the knowledge, attitudes and behaviour scores on medication administration error according to nurses' sociodemographic and professional variables. STUDY DESIGN: This is a secondary analysis of data from a cross-sectional international study based on a survey. Descriptive statistics were computed for all items of the questionnaire. Non-parametric tests (Kruskal Wallis and Mann Whitney U tests) were used to carry out the comparison between groups. RESULTS: The international sample consisted of 1383 nurses in 12 different countries. Statistically significant changes were seen in knowledge, attitudes and behaviour scores among several subgroups of the international population. Eastern nurses were more likely to show adequate knowledge about medication administration error prevention than Western nurses; concurrently, Western nurses were significantly more likely to show positive attitudes than Eastern nurses. No statistically significant differences in the behaviour scale were found in this study. CONCLUSIONS: The findings show a difference between knowledge and attitudes in relation to cultural background. RELEVANCE TO CLINICAL PRACTICE: Decision makers in ICUs should consider cultural background when planning and implementing prevention strategies for medication administration errors. Further research is needed to investigate the effectiveness of educational systems on the decrease of the incidence of medication administration errors in ICU.

A sensation for inflation: initial swim bladder inflation in larval zebrafish is mediated by the mechanosensory lateral line.

Larval zebrafish achieve neutral buoyancy by swimming up to the surface and taking in air through their mouths to inflate their swim bladders. We define this behavior as 'surfacing'. Little is known about the sensory basis for this underappreciated behavior of larval fish. A strong candidate is the mechanosensory lateral line, a hair cell-based sensory system that detects hydrodynamic information from sources such as water currents, predators, prey and surface waves. However, a role for the lateral line in mediating initial inflation of the swim bladder has not been reported. To explore the connection between the lateral line and surfacing, we used a genetic mutant (lhfpl5b-/-) that renders the zebrafish lateral line insensitive to mechanical stimuli. We observed that approximately half of these lateral line mutants over-inflate their swim bladders during initial inflation and become positively buoyant. Thus, we hypothesized that larval zebrafish use their lateral line to moderate interactions with the air-water interface during surfacing to regulate swim bladder inflation. To test the hypothesis that lateral line defects are responsible for swim bladder over-inflation, we showed that exogenous air is required for the hyperinflation phenotype and transgenic rescue of hair cell function restores normal inflation. We also found that chemical ablation of anterior lateral line hair cells in wild-type larvae causes hyperinflation. Furthermore, we show that manipulation of lateral line sensory information results in abnormal inflation. Finally, we report spatial and temporal differences in the surfacing behavior between wild-type and lateral line mutant larvae. In summary, we propose a novel sensory basis for achieving neutral buoyancy where larval zebrafish use their lateral line to sense the air-water interface and regulate initial swim bladder inflation.

The accuracy of radial artery applanation tonometry and intra-arterial blood pressure monitoring in critically ill patients: An evidence-based review.

The invasive intra-arterial approach is the gold standard for measuring blood pressure in intensive care units where accuracy is crucial. However, invasive procedures increase the risk of infections and mortality. This evidence-based review aimed to determine whether continuous non-invasive blood pressure (CNIBP) monitoring, using Radial Artery Applanation Tonometry (RAAT) devices, is as accurate as invasive methods. Six papers were included: three prospective cohort studies and three comparative studies. Most studies showed that mean arterial pressure is accurately recorded through RAAT monitoring; however, more research is needed to assess the accuracy of non-invasive readings of systolic and diastolic blood pressures, as data are not always concordant.

Chlorhexidine-based versus non-chlorhexidine dressings to prevent catheter-related bloodstream infections: An evidence-based review.

In patients with central venous catheters (CVCs) in situ, the development of catheter-related bloodstream infections (CRBSIs) is often linked with increased morbidity and mortality. Sterile gauze or transparent polyurethane dressings are conventionally used as extraluminal barriers; however, antimicrobial chlorhexidine CVC dressings could potentially reduce infection risk. This short evidence-based review examined the literature comparing the effectiveness of chlorhexidine-based CVC dressings against non-chlorhexidine dressings in reducing CRBSI occurrence. Four systematic reviews with meta-analysis were reviewed, all of which reported a statistically significant reduction in CRBSI occurrence on using chlorhexidine-based dressings. Further research is needed to determine the cost-effectiveness of chlorhexidine-based CVC dressings and their effectiveness in reducing CRBSIs in different catheter types and entry sites because infection risk is not uniform.

Enlargement of Ribbons in Zebrafish Hair Cells Increases Calcium Currents But Disrupts Afferent Spontaneous Activity and Timing of Stimulus Onset.

In sensory hair cells of auditory and vestibular organs, the ribbon synapse is required for the precise encoding of a wide range of complex stimuli. Hair cells have a unique presynaptic structure, the synaptic ribbon, which organizes both synaptic vesicles and calcium channels at the active zone. Previous work has shown that hair-cell ribbon size is correlated with differences in postsynaptic activity. However, additional variability in postsynapse size presents a challenge to determining the specific role of ribbon size in sensory encoding. To selectively assess the impact of ribbon size on synapse function, we examined hair cells in transgenic zebrafish that have enlarged ribbons, without postsynaptic alterations. Morphologically, we found that enlarged ribbons had more associated vesicles and reduced presynaptic calcium-channel clustering. Functionally, hair cells with enlarged ribbons had larger global and ribbon-localized calcium currents. Afferent neuron recordings revealed that hair cells with enlarged ribbons resulted in reduced spontaneous spike rates. Additionally, despite larger presynaptic calcium signals, we observed fewer evoked spikes with longer latencies from stimulus onset. Together, our work indicates that hair-cell ribbon size influences the spontaneous spiking and the precise encoding of stimulus onset in afferent neurons.SIGNIFICANCE STATEMENT Numerous studies support that hair-cell ribbon size corresponds with functional sensitivity differences in afferent neurons and, in the case of inner hair cells of the cochlea, vulnerability to damage from noise trauma. Yet it is unclear whether ribbon size directly influences sensory encoding. Our study reveals that ribbon enlargement results in increased ribbon-localized calcium signals, yet reduces afferent spontaneous activity and disrupts the timing of stimulus onset, a distinct aspect of auditory and vestibular encoding. These observations suggest that varying ribbon size alone can influence sensory encoding, and give further insight into how hair cells transduce signals that cover a wide dynamic range of stimuli.

Teaching Dose-response Relationships Through Aminoglycoside Block of Mechanotransduction Channels in Lateral Line Hair Cells of Larval Zebrafish.

Here we introduce a novel set of laboratory exercises for teaching about hair cell structure and function and dose-response relationships via fluorescence microscopy. Through fluorescent labeling of lateral line hair cells, students assay aminoglycoside block of mechanoelectrical transduction (MET) channels in larval zebrafish. Students acquire and quantify images of hair cells fluorescently labeled with FM 1-43, which enters the hair cell through MET channels. Blocking FM 1-43 uptake with different concentrations of dihydrostreptomycin (DHS) results in dose-dependent reduction in hair-cell fluorescence. This method allows students to generate dose-response curves for the percent fluorescence reduction at different concentrations of DHS, which are then visualized to examine the blocking behavior of DHS using the Hill equation. Finally, students present their findings in lab reports structured as scientific papers. Together these laboratory exercises give students the opportunity to learn about hair cell mechanotransduction, pharmacological block of ion channels, and dose-dependent relationships including the Hill equation, while also exposing students to the zebrafish model organism, fluorescent labeling and microscopy, acquisition and analysis of images, and the presentation of experimental findings. These simple yet comprehensive techniques are appropriate for an undergraduate biology or neuroscience classroom laboratory.

Intensity-dependent timing and precision of startle response latency in larval zebrafish.

KEY POINTS: Using high-speed videos time-locked with whole-animal electrical recordings, simultaneous measurement of behavioural kinematics and field potential parameters of C-start startle responses allowed for discrimination between short-latency and long-latency C-starts (SLCs vs. LLCs) in larval zebrafish. Apart from their latencies, SLC kinematics and SLC field potential parameters were intensity independent. Increasing stimulus intensity increased the probability of evoking an SLC and decreased mean SLC latencies while increasing their precision; subtraction of field potential latencies from SLC latencies revealed a fixed time delay between the two measurements that was intensity independent. The latency and the precision in the latency of the SLC field potentials were linearly correlated to the latencies and precision of the first evoked action potentials (spikes) in hair-cell afferent neurons of the lateral line. Together, these findings indicate that first spike latency (FSL) is a fast encoding mechanism that can serve to precisely initiate startle responses when speed is critical for survival. ABSTRACT: Vertebrates rely on fast sensory encoding for rapid and precise initiation of startle responses. In afferent sensory neurons, trains of action potentials (spikes) encode stimulus intensity within the onset time of the first evoked spike (first spike latency; FSL) and the number of evoked spikes. For speed of initiation of startle responses, FSL would be the more advantageous mechanism to encode the intensity of a threat. However, the intensity dependence of FSL and spike number and whether either determines the precision of startle response initiation is not known. Here, we examined short-latency startle responses (SLCs) in larval zebrafish and tested the hypothesis that first spike latencies and their precision (jitter) determine the onset time and precision of SLCs. We evoked startle responses via activation of Channelrhodopsin (ChR2) expressed in ear and lateral line hair cells and acquired high-speed videos of head-fixed larvae while simultaneously recording underlying field potentials. This method allowed for discrimination between primary SLCs and less frequent, long-latency startle responses (LLCs). Quantification of SLC kinematics and field potential parameters revealed that, apart from their latencies, they were intensity independent. We found that increasing stimulus intensity decreased SLC latencies while increasing their precision, which was significantly correlated with corresponding changes in field potential latencies and their precision. Single afferent neuron recordings from the lateral line revealed a similar intensity-dependent decrease in first spike latencies and their jitter, which could account for the intensity-dependent changes in timing and precision of startle response latencies.