In 1995, a system for checking anaesthetic machines was developed and given the name 'COVERS' . That system was reported in this journal and we considered it to be superior to that generally recommended at the time .
COVERS has two components. First there is, COVERS itself, a pre-use checklist the completion of which is noted in the diary for the machine wherein any problems must also be recorded. Secondly, there is a comprehensive checklist to eliminate non-recurring faults which is completed by an anaesthetist and operating department practitioner or equivalent member of staff together when a machine is returned from service or breakdown before it resumes front-line duty.
The Checklist for Anaesthetic Equipment 2004 recently issued by the Association of Anaesthetists of Great Britain and Ireland includes changes that are pertinent with respect not only to the anaesthetic machine and associated equipment but also to address breathing system incident concerns .
In this publication (Section 2: procedures) we note the sensible change that, whilst implementation of the checks remains the responsibility of the anaesthetist who must be satisfied that they have been carried out correctly, the task itself may be undertaken by a suitably trained member of the team. New inclusions are first, the requirement for the oxygen failure alarm to be checked on a weekly basis and, secondly, the need to have immediately available an alternative means to ventilate the patient including an oxygen cylinder. Also, the new guidance that confirmation of pre-use checking should be recorded in the logbook/diary provided with the anaesthetic machine, as we currently do, is valuable.
The advice that 'the "first user" check after servicing is especially important and must be recorded as such' is restated in the guidelines but still no advice is given as to the form that this should take. Our current practice in this regard has two components:
(a) The "A" check which is the pre-use checklist carried out by the responsible operating department practitioner alone without any time pressure first, after return of the anaesthetic machine from simple repair when no disassembly has taken place and, secondly, twice between services as a back up to the daily checks.
(b) The "B" check which is a comprehensive check-list  carried out by anaesthetist and operating department practitioner together following the six monthly service or any major repair requiring reassembly.
We particularly commend this practice to all readers any of whom can be supplied with a copy of the comprehensive checklist on request.
Our department considers that the 2004 Association of Anaesthetists recommendations are now appropriate to adopt as the standard pre-use checklist and COVERS will be exchanged for these which will introduce a conformity of additional benefit to our rotating trainees.
We continue to believe, however, that use of the comprehensive checklist in addition and as described is very necessary and should be a part of routine practice and teaching.
A. P. J. Lake
P. A. Jones
Department of Anaesthesia; Conwy & Denbighshire NHS Trust; Denbighshire, UK
1. Krimmer M, Lake APJ, Wray I. COVERS for anaesthetic machines: an audit and standard. Eur J Anaesthesiol
2. The Association of Anaesthetists of Great Britian and Ireland. Checklist for Anaesthetic Machines, a Recommended Procedure Based on the Use of an Oxygen Analyser.
London: The Association of Anaesthetists of Great Britain and Ireland, 1990.
3. The Association of Anaesthetists of Great Britain and Ireland. Checking Anaesthetic Equipment 3 2004.
London: The Association of Anaesthetists of Great Britain and Ireland, 2004.
4. Carter JA. Checking anaesthetic equipment and the expert group on blocked anaesthetic tubing. Anaesthesia