Medical device regulation: requirements for occupational therapists in The Netherlands who prescribe and manufacture custom-made devices.

PURPOSE: To interpret the Medical Device Regulation for occupational therapists in the Netherlands involved in prescribing and manufacturing custom-made assistive devices and to develop a roadmap for implementation. MATERIALS AND METHODS: Four online iterative co-design workshops were organized under supervision of a senior quality manager to assist in the interpretation of the MDR framework with a focus on custom-made assistive devices; and to assist the implementation by generating guidelines and forms. The workshops for seven participating occupational therapists had an interactive character with Q&A, small and homework assignments, and oral evaluations. Next to occupational therapists, participants with different backgrounds joined such as 3D printing experts, engineers, managers, and researchers. RESULTS: The participants experienced the interpretation of the MDR as informative, but also as complex . Complying with the MDR requires considerable documentation activities that are currently not part of care professionals tasks. This initially raised concerns regarding implementation in daily practice. To facilitate the MDR implementation, forms were created and evaluated for a selected design case together with the participants for future reference. Additionally, instructions were given which forms should be filled out only once per organization, which forms could be reused for similar types of custom-made devices, and which forms should be filled out for each individual custom-made device. CONCLUSIONS: This study provides practical guidelines and forms to support occupational therapists in the Netherlands to prescribe and manufacture custom-made medical devices complying with the MDR. It is recommended to involve engineers and/or quality managers in this process.IMPLICATIONS FOR REHABILITATIONOccupational therapists are considered legal manufacturer when they prescribe and manufacture custom-made medical devices for their clients. As such they are legally obliged to meet the Medical Device Regulation (MDR).When designing and manufacturing "in-house" custom-made medical devices, care organizations need to follow and document activities to demonstrate compliance with the MDR. This study offers practical guidelines and forms to facilitate this.

Monitoring haemodynamic changes in rodent models to better inform safety pharmacology: Novel insights from in vivo studies and waveform analysis.

Animal models are essential for assessing cardiovascular responses to novel therapeutics. Cardiovascular safety liabilities represent a leading cause of drug attrition and better preclinical measurements are essential to predict drug-related toxicities. Presently, radiotelemetric approaches recording blood pressure are routinely used in preclinical in vivo haemodynamic assessments, providing valuable information on therapy-associated cardiovascular effects. Nonetheless, this technique is chiefly limited to the monitoring of blood pressure and heart rate alone. Alongside these measurements, Doppler flowmetry can provide additional information on the vasculature by simultaneously measuring changes in blood flow in multiple different regional vascular beds. However, due to the time-consuming and expensive nature of this approach, it is not widely used in the industry. Currently, analysis of waveform data obtained from telemetry and Doppler flowmetry typically examines averages or peak values of waveforms. Subtle changes in the morphology and variability of physiological waveforms have previously been shown to be early markers of toxicity and pathology. Therefore, a detailed analysis of pressure and flowmetry waveforms could enhance the understanding of toxicological mechanisms and the ability to translate these preclinical observations to clinical outcomes. In this review, we give an overview of the different approaches to monitor the effects of drugs on cardiovascular parameters (particularly regional blood flow, heart rate and blood pressure) and suggest that further development of waveform analysis could enhance our understanding of safety pharmacology, providing valuable information without increasing the number of in vivo studies needed.

Background on methods of stimulation in galvanic-induced body sway in young healthy adults.

The aim of this study was to develop a standardized procedure for reproducible quantification of galvanic-induced body sway (GBS). This was a prospective experimental study conducted in a tertiary referral centre. An exploratory study was first conducted to define the galvanic vestibular stimulation (GVS) method that resulted in the best reproducible responses. Ten subjects underwent computer-controlled GVS using five different types of monaural and binaural stimulation with 2-mA currents. Cosinusoidal stimulation gave the most reproducible responses. The frequency and current variability of this stimulus type were then tested in the same 10 subjects. A monaural continuous 1-cosinusoidal current of 0.5 Hz and 2 mA gave the most reproducible responses (< 20% test-retest variation) and the largest GBS amplitude. The other (sinusoidal) stimuli resulted in variabilities exceeding 50%. This stimulus was thus used for further testing in our normative study. In this study we measured GBS amplitude at 0.5 Hz in 60 subjects, with eyes closed and an inter-feet distance of 0 cm, using a force platform. In addition to body sway, responses included slight dizziness, taste sensations and a tingling sensation at the site of stimulation. Habituation to the applied stimulus was seen. Binaural prestimulation, performed in 50/60 test subjects, is necessary to reduce habituation and achieve optimal reproducibility in order to be able to compare the sensitivity of the left and right vestibular systems. The test-retest variability was determined in detail in 12 additional subjects. Prestimulation reduced habituation, but improved the sensitivity of the method; some test-retest variability persisted (< 20%).