Correspondence 921

useful residual analgesia following bupivacaine is due to 'spillage' of the agent into the wound or fracture site during and after surgery and as such is certainly concentration dependent. The relevance of a volunteer study therefore seems questionable.

The fact that trial results were included pre- publication in promotional material for bupivacaine should not have given serious cause for concern since full instructions and a dosage scheme appear i n the same handout (and are repeated in the data sheet for bupivacaine). I t is possible to use undiluted 0.25% bupivacaine plain for IVRA but, in my opinion, the incidence of 'uncomfortable' paraes- thesiae on injection is unacceptably high especially in trauma patients.

I t is surprising considering Dr Wildsmith and his colleagues obvious mistrust of promotional literature to find their statement that 'prilocaine . . . is the agent of choice for IVRA' backed up by a reference to the Illrrstratetl Handbook iir Loccrl Anaesthesin, a book produced by A.B. Astra Ltd, the manufac- turers of prilocaine.

Obviously there is 3 fundamental difference i l l

opinion regarding the agent of choice for IVRA. Bupivacaine used as described3 seems to be remarkably free from adverse effects and to produce very effective operative analgesia. Prilocaine has yet to achieve popularity in British anaesthetic prac- tice. Hopefully, an early trial of prilocaine against bupivacaine will settle the question of 'the agent of choice' for IVRA to everyone's satisfaction.

King's College Hospital, R.J. WARE Denmark Hil l , London SES 9RS.

Re fercnccs

I . THORN-ALQUIST, A.M. (1971) Intravenous regional analgesia. Arlo Anrirsfh(~sio/i~ii.o Si ont/inurii ( I . IS, 23.

D.B. (1974) Residual nerve block following intra- venous anaest hesia. Briri.sh Joririrrrl o/'Anoesrhc.~ia, 46.

3 . W A R E , R.J. (1975) Intravenous regional analgesia using hupivacaine. Anaesthesia, 30, 817.

2 . EVANS, C.J., DEWAR. J.A.. BOYES, R.N. & SCOTT.

Prevention of hearing under anaesthesia

I t is a problem, well known to anaesthetists, that patients whilst under a general anaesthetic may be aware of things happening around them. Some of these patients can hear and remember conversations between clinical staff during an operation. This can be an extremely distressing situation for the patient and as a result it was decided to try and block the patients hearing. A cheap simple solution was required and it was decided to provide a set of headphones with a continuous background noise.

A pair of well padded headphones with a volume control were chosen. These are available at any audio retail shop and are quite inexpensive. Hi-Fi quality is not required so the main point to select is padding for good comfort. The headphone lead is removed, and inside the speaker housing a small 'white noise generator' is inserted, using a reverse biased transistor junction to generate a hissing sound which has a very broad frequency spectrum (white noise). The circuit is powered by a PP3 battery and is entirely contained within the head- phone housing. All components are readily available and the time taken to modify the headphones is very short.

After the patient has been anaesthetised the unit is switched on and the volume set at a suitable level. The headphones are then placed over the ears and left there until the completion of the operation.

This simple expedient of preventing hearing seems to be most effective and is now routinely used in maternity theatre. The circuit can be readily con- structed by anyone with the slightest knowledge of electronics and since the unit is battery operated, there is no problem with electrical safety. Should anyone require further information then L.J. Grant, at the address below, will be pleased to supply it.

Wiltshire Area Medical Physics Serike, Royal United Hospital, L.J. GRANT Cornhe Prrrk, M.A. PERKINS Bath. Prirrcess Margaret Hospital, P.C. BABINGTON Swindon, Wiltshire.

Communication

Me, you and them

I recently wrote for you a review of some audio- visual material (Anaesthesia, 34, 384). In it I wrote

'One major point worries me'. You printed 'One major point worries yortr reciewer'. What have you got against rile and all your other authors. The Editorial in the same issue (Anaesthesia, 34,299-300)

922 Correspondence

starts ‘The writer entered consultant anaesthetic practice 30 years ago’. Another paper (Anaesthesia, 34,341-343) states ‘It is the opinion ofthe author. . .’.

When I am lecturing, I do not say ‘The lecturer believes.. .’; I say ‘ I believe.. .’. It would make my reading easier if you dropped this convention.

Department of Anuesthetics, JOHN NORMAN University of Southampton, Southampton General Hospitnl. Southampton SO9 4 X Y .

A reply froni the Editor

This letter was originally sent to the Editor prefixed by his Christian name and was assumed to be in- tended as a private communication from a brother editor, but Professor Norman has requested that it should be published. We therefore see no reason why we should not make a similar reply in public to that which we made in private.

It is our policy to eliminate the first person singu- lar and plural in all scientific papers and in almost all other matter (letters to the correspondence pages being an exception). Our own opinion is that reiteration of ‘I’ and ‘We’ sometimes conveys the impression that ‘I’ or ‘We’ are telling the world how good they are.

We do not intend to alter our policy so far as scientific papers areconcerned but we have, from time to time, made some exceptions with other material at the request of the writer. We allow ourselves some latitude so far as editorials are concerned, although, of course, the editorial to which Professor Norman refers specifically was not in fact written by the Editor himself. The only other comment which we would make is that ‘lecturing’ is not ‘writing’ and it is, in fact, often very difficult indeed to prepare a script which is suitable for both the written and the spoken word as many eponymous lecturers have found to their chagrin.

The Editor