Preliminary observations of a system for determination of phototherapy exposure over a neonate body shape.

While it is possible to determine the irradiance and spectral content for a given neonatal phototherapy device at various locations over a neonate's surface, this does not allow estimation of the total rate of energy delivery within a specific spectral range over the neonate's exposed body surface. A series of 192 blue wavelength enhanced silicon photodiodes was distributed over the surface of a commercially available newborn body shape and connected to a specially designed interface circuit. Placement of photosensors over the surface of the baby shape was determined with consideration of the surface area of twelve specific anatomical areas where each was allocated 16 individual photodiodes.

Use of a hand-held spectroradiometer for the measurement of neonatal phototherapy lamp outputs.

The measurement capability of a hand-held spectroradiometer for validation of phototherapy light treatment for neonates is described. This function is compared with that of a double grating monochromator system with photomultiplier detector, where parameters evaluated included wavelength accuracy and accuracy of irradiance within set wavelength intervals - 460 nm to 490 nm and 400 nm to 550 nm. Measurements carried out in a clinical setting revealed that the hand-held spectroradiometer provided an acceptable level of accuracy for determining output characteristics of the phototherapy devices investigated.

Medical Device Guidebook: A browser information resource for medical device users.

A web based information resource - the 'Medical Device Guidebook' - for the enabling of safe use of medical devices is described. Medical devices are described within a 'catalogue' of specific models and information on a specific model is provided within a consistent set of information 'keys'. These include 'user manuals', 'points of caution', 'clinical use framework', 'training/assessment material', 'frequently asked questions', 'authorised user comments' and 'consumables'.

Safety of neonatal phototherapy lamp exposure.

A routine review of light exposure within a neonatal intensive care unit is described following the introduction of a new model of neonatal phototherapy lamp. Spectral measurements were undertaken using a Bentham Dmc150 spectroradiometer system. Safety assessments were undertaken based on likely exposure of parents at the cot side, neonates in adjacent cots and the effectiveness of eye protection for neonates with direct phototherapy.

Determination of pulse profile characteristics of multi spot retinal photocoagulation lasers.

A system is described for determination of discrete pulse train characteristics of multi spot laser delivery systems for retinal photocoagulation. While photodiodes provide an ideal detection mechanism, measurement artifacts can potentially be introduced by the spatial pattern of the delivered beam relative to a discrete photodiode element. This problem was overcome by use of an integrating sphere to produce a uniform light field at the site of the photodiode detector.

Light protection of chemotherapy drugs for infusion.

Specific chemotherapy drugs which require to be delivered by continuous infusion over time can have their effectiveness impaired by exposure to optical radiation. Mechanisms and processes of drug preparation and patient administration associated with light sensitive drugs were monitored within a Chemotherapy Unit. Levels of ambient light at locations of drug preparation/administration and levels of protection afforded by optical filter elements such as infusion lines were determined using a double grating Bentham Dmc150 spectroradiometer.

Measurement of compliance of infusion device consumable elements using an analytical weighing balance.

The value of compliance of disposable elements such as infusion lines and syringes can significantly affect the performance characteristics of infusion devices. In a technique used to determine the compliance of infusion lines, the item under test is placed in a semi sealed water filled enclosure and the volume of fluid displaced is measured on an analytical weighing balance as set pressures are applied to the test item. Thermal drift of the measurement chamber was minimised by inclusion of discs of Invar alloy.

Neonatal phototherapy radiometers: current performance characteristics and future requirements.

Hand held radiometers provide a convenient means of monitoring the output of neonatal phototherapy treatment devices as part of planned programs of device maintenance and output monitoring. It was considered appropriate to determine the wavelength and angular response of a selection of such meters and compare their indicated values with that derived from spectral analysis of phototherapy light sources. This was undertaken using a Bentham DMc150 double grating spectroradiometer and a series of 10nm band pass optical filters in the range 400-640 nm used in conjunction with a fiber optic light source.

Preliminary measurement of gas concentrations of perfluropropane using an analytical weighing balance.

We describe the use of an analytical weighing balance of measurement accuracy 0.00001g for determination of concentrations of perfluropropane (C3F8) gas used in ophthalmic surgical vitrectomy procedures. A range of test eyes corresponding to an eye volume of 6.

Patient weighing: standardisation and measurement.

Identification of patients with specific nutritional needs requires the use of appropriate weighing systems. The introduction of the Non-Automated Weighing Instruments Directive for equipment requiring an operator (Directive 2009/23/EC of the European Parliament) in hospitals in the UK has provided a framework for standardisation of measurement accuracy in weighing equipment. This article outlines the recommendations of the directive.

Exploring the clinical effects of height elevation and depression on syringe pumps.

Research has shown that the positioning of syringe pumps can have a significant effect on the amount of drug delivered t opatients. This article explains the effects of raising and lowering syringe pumps in relation to the entry site, and its impact on drug delivery. It also discusses drugs which are particularly associated with risks to patients when the device height is changed, and measures to reduce the clinical impact of height elevation and depression of infusion lines, including training.