Pump Reports

BIME evaluation reports published since 2002 are available in electronic form and are summarised below. Earlier reports can be ordered from us. Reports of some recently completed projects, including buyers' guides, are availbale from the Home Page.

Database of evaluation reports of 26 infusion devices (2003)

Summary of several completed projects:

McKinley T34 syringe driver – Report 05076 (March 06)

This report is a technical, user and usability evaluation of the new McKinley T34 syringe pump launched in the UK in May 2005. The McKinley T34 syringe pump, commonly referred to as a syringe driver due to its small size, is a niche product with a potentially large market. The report provides technical performance results, a user assessment performed by questionnaire, and a rule-based review of usability performed by experts.

The report is aimed at pain management teams, palliative care, hospice and community nurses and, to some extent general ward staff, also including purchasing officers dealing with these areas. In addition to the expected realms of application, the manufacturer proposes the pump as suitable for general ward use, despite its small size (16.5 cm x 5.5 cm x 3.5 cm). A few features common to ward pumps, such as the ability to load a full 50 ml syringe, are absent. Clinical staff would need to examine this claim carefully before adopting the T34 in a particular ward setting. The pump requires the optional mains powered docking station in order to work from mains power, or be attached to a pole.

The McKinley T34 specifically and principally aims at a particular clinical niche (ambulatory small volume drug therapy) currently filled by similar pumps, all of which fail to address a few of the fundamental safety requirements delineated by IEC 60601-2-24. The T34 is the first ambulatory syringe pump which addresses all of the safety features that the above named Standard for infusion technology proposes as essential for compliance. Compliance with IEC 60601-2-24 is therefore a strong competitive selling point for this simple pump. The pump retains the small size of competitive devices, with some increase in weight and a significant protrusion on the reverse surface, in order to accommodate the mechanism for detection of syringe size. This means that the pump can genuinely be programmed in ml/h rather than mm/h or mm/24h, thereby reducing the opportunities for user error, and the associated possibility of serious under or overdose. Some of the competitive devices nominally allow programming in ml/h but depend on the user to use only one size of syringe, whilst providing no means of detecting error. The T34 detects syringe size. The device has undergone significant change since being presented for testing; a few teething troubles are noted within this report, including unexpected flow anomalies and some usability issues. McKinley are a highly interactive company and have remedied some of the faults highlighted both by this investigation and early users. Later adopters are likely to find fewer problems.

Report_05076.pdf (935 KB)

Market survey: non-electrically powered disposable infusion devices - Report 05055 (Sept 05)

Non-electrically powered disposable infusion devices have been in clinical use for more than twenty years. During this period, the possible areas of application have increased as well as the number of patients receiving these types of therapy. Disposable infusion devices are extensively used both in public and private healthcare to deliver therapies such as chemotherapy, antimicrobials, post-operative pain control and chronic pain management.

During the past fifteen years, a large number and variety of disposable pumps has become available from manufacturers distributed around the world. These products differ from each other over a wide range of specifications and the potential buyer can face a significant problem in selecting an appropriate disposable infusion device for their application.

The present report is intended to provide comparative specifications of nonelectrically powered disposable infusion devices available on the UK market. It aims to provide potential customers with data on these devices in standardised format, thus assisting in device selection according to the therapy and the device specifications.

All data in this report is taken from the manufacturers’ product brochures and accompanying documentation, or has been supplied as supplementary information by the manufacturers, on request. Any feature listed in the tables as N/A is not applicable for the particular device. No performance testing was carried out for this report; all claims in respect of performance are the manufacturer’s own.

The data in the report is grouped according to the type of disposable pump: elastomeric, spring-powered, gas pressure pumps, patient controlled analgesia (PCA) devices and disposables combining PCA with a background continuous infusion. There is a brief introduction on each type of pump at the beginning of each section, followed by a table with pump specifications. Data on the pumps in each section is presented in alphabetical order according to pump name. Prices given in the report were provided by the manufacturers and are commonly negotiable for bulk orders. Contact details for each manufacturer and their UK representatives are given at the end of the report in the appendix. In addition, references to all cited papers are listed at the end of the report.

Report_05055.pdf (2,030 KB)

Target Controlled Infusion (TCI) systems Part One: Diprifusor Pumps - MHRA 04146 (June 05)

This report is a comparative review of three syringe pumps offering intravenous anaesthesia by target controlled infusion (TCI) using the Diprifusor module. The pumps have been evaluated to offer potential purchasers guidance on which product may best meet their needs. It will also be of value in relation to forthcoming reports evaluating more recent systems which also offer TCI anaesthesia. This report evaluates three current syringe pumps:

• Fresenius Vial Master TCI
• Alaris IVAC P 6000 TCI
• Terumo TE 372 TCI

In technical performance testing, performance for each pump was sufficiently accurate to be considered clinically acceptable. For all three pumps, drug concentration calculated from actual fluid delivery was seen to deviate 10 - 20% from target concentration after certain events (syringe change, line occlusion or pump being raised on a drip stand). These errors reduced to less than 5% within a few minutes in all cases. None of the data supports making a distinction between the devices on the grounds of technical performance.

The heuristic review assessed pump usability by combining three independent assessments of usability problems when completing clinically typical tasks, and listing the heuristic violations for these problems as well as rating them for severity (based on clinical significance). While the usability problems differed for the pumps, the total number of problems and heuristic violations, and the spread of severity of the problems were similar for all three pumps. The Fresenius pump had 66 usability problems identified, and 172 heuristic violations. The Alaris pump had 68 problems and 184 heuristic violations, and the Terumo pump had 64 problems and 163 heuristic violations.

The questionnaire survey yielded a range of views from anaesthetists, showing a generally high regard for the safety and usability of all the pumps carrying the Diprifusor module. The average overall rating by anaesthetists (on a scale from 1 to 5) was 3.7 for the Fresenius pump, and 4.0 for the Alaris and Terumo pumps.

Report_04146.pdf (824 KB)

Target controlled infusion (TCI) systems part two: Alaris Asena PK - Report 05045 (Aug 05)

This report is a technical evaluation of the Alaris Asena PK syringe pump with respect to its use for the delivery of intravenous anaesthesia by target controlled infusion (TCI). It follows on from a recent evaluation of three pumps also designed for TCI use. Testing has been conducted according to the same protocols to facilitate direct comparison and thereby offer potential purchasers guidance on which product may best meet their need.

The pump was separately tested for technical performance (focussed on performance in TCI mode), and usability (assessed by means of a laboratory based heuristic review coupled with a questionnaire survey of anaesthetists).

In technical performance testing, performance was sufficiently accurate to be considered clinically acceptable. Drug concentration calculated from actual fluid delivery was seen to deviate 10 - 20% from target concentration after certain events (syringe change, line occlusion or pump being raised on a drip stand). These errors reduced to less than 5% within a few minutes in all cases. None of the data supports making a distinction between this pump and other evaluated TCI pumps on the grounds of technical performance. The Alaris Asena PK does, however, offer a greater functionality than the previously evaluated Diprifusor pumps in that it offers alternative pharmacokinetic models and offers either plasma or effect site steering. Several models are supplied as standard (including the Marsh model for propofol and the Minto model for remifentanil) and further models are available for purchase. Technical performance was equally good in tests on the alternative models.

The heuristic review assessed pump usability by combining three independent assessments of usability problems when completing clinically typical tasks (including tasks relating to use of the advanced functionality), and listing the heuristic violations for these problems as well as rating them for severity based on clinical significance. 108 usability problems were highlighted, and 279 heuristic violations linked to these problems. Over 90% of these problems were rated as ‘minor’ or ‘cosmetic’ in terms of severity, while there were eight ‘major’ problems and one problem that was given a ‘catastrophic’ rating. This problem relates to the tendency of the RUN key and other keys to fail to register every time they are pressed. Alaris are investigating this finding. Overall the spread of problems and heuristic violations was similar to previously evaluated pumps, but with a higher total number of problems found – this may be a result of the increased functionality of the pump and the additional tasks performed by evaluators to assess this functionality.

The questionnaire survey yielded a range of views from anaesthetists, showing a generally high regard for the functionality, safety and usability of the pump, though with several recommendations for possible improvements in these areas. The average overall rating by anaesthetists (on a scale from 1 to 5) was 4.1.

Report_05045.pdf (705 KB)