Objectives: This study aimed to investigate the technical documentation of manufacturers on issues of safe use of their device in a home setting.

Methods: Three categories of equipment were selected: infusion pumps, ventilators, and dialysis systems. Risk analyses, instructions for use, labels, and post market surveillance procedures were requested from manufacturers. Additionally, they were asked to fill out a questionnaire on collection of field experience, on incidents, and training activities.

Results: Specific risks of device operation by lay users in a home setting were incompletely addressed in the risk analyses. A substantial number of user manuals were designed for professionals, rather than for patients or lay carers. Risk analyses and user information often showed incomplete coherence. Post market surveillance was mainly based on passive collection of field experiences.

Conclusions: Manufacturers of infusion pumps, ventilators, and dialysis systems pay insufficient attention to the specific risks of use by lay persons in home settings. It is expected that this conclusion is also applicable for other medical equipment for treatment at home. Manufacturers of medical equipment for home use should pay more attention to use errors, lay use and home-specific risks in design, risk analysis, and user information. Field experiences should be collected more actively. Coherence between risk analysis and user information should be improved. Notified bodies should address these aspects in their assessment. User manuals issued by institutions supervising a specific home therapy should be drawn up in consultation with the manufacturer.

Summary

Background and objective: For use in a magnetic resonance (MR) scanning room infusion pumps must be MR safe and compatible. This study tested two commonly used infusion pumps (Alaris P6000 and Alaris Asena-GH) to determine if they met these criteria.

Methods: The pumps underwent testing within the scanning room of a 3 T MR scanner. Pump infusion rates were tested at up to 100 Gauss magnetic field strength, with and without radio frequency signals present. The effect of the pumps on image quality was assessed. The occlusion pressure alarm of the pumps was tested at up to 100 Gauss. The projectile risk was assessed by measuring the force exerted upon the pumps at the entrance to the scanner.

Results: The maximum mean flow rate errors at 100 Gauss were 2.18% for the Alaris P6000 and 1.42% for the Alaris Asena-GH, both within our accepted limits. Radio frequency signals had no effect on flow rate. The pumps produced no discernable artefacts on the acquired images. The maximum mean occlusion pressure error was 204 mmHg higher for the Alaris P6000 pump and 99 mmHg lower for the Alaris Asena-GH (P-values < 0.001) at 100 Gauss compared to testing outside the scanner. Both pumps were subject to significant attractive force at the entrance to the scanner.

Conclusions: Whilst the pumps cannot strictly be termed MR safe or compatible at 100 Gauss we have demonstrated that flow rates are unchanged and that, for the Alaris Asena-GH, the effect on the occlusion pressure alarm is unlikely to have patient safety implications.

Background and objective: We measured the physical performance error of commercial syringe pumps incorporating the Diprifusor® module to deliver propofol by target-controlled infusion in a laboratory experiment.

Methods: Three infusion devices (Graseby 3500®; Fresenius Vial Master TCI®; Alaris TIVA-TCI®) were studied when infusing propofol at six different target concentrations (1, 1.5, 2, 3, 5, 8 µg mL−1) over 10 min. This procedure was repeated five times to average each target. Precision measurements were based on the volume delivered and a mean performance error was calculated.

Results: The mean performance error bandwidth for all pumps was from −2.07 to 4.22% with a 95% confidence interval always <4.5%. There was a higher variability at lower target concentrations associated with lower infusion rates. The Alaris TIVA-TCI® pump showed the largest overall bias whereas the Fresenius Vial Master TCI® pump had the smallest divergence and the lowest variation across all target concentrations. The Graseby 3500® pump had the smallest range in mean performance error with an acceptable variation (95% CI <2%).

Conclusions: Despite the differences between the pumps, which may be related to the synchronization of the hardware components, the absolute inaccuracies in the physical performance were low and presumably negligible from a clinical point of view.

Concerns about life support equipment accompanying the critically ill patient have to date made magnetic resonance imaging (MRI) studies of this patient group the exception. We present here a series of tests performed on an IVAC P3000 infusion pump to investigate its suitability for the magnetic resonance imaging environment. We investigate safety, pump performance and image quality issues. The pump was housed at the end of the patient couch to prevent motion towards the scanner. Gravimetric tests found the pump to work within acceptable parameters at a static field of 10 mT. Image interference issues were addressed.