Dear Editor,

I could not resist replying, even though time has passed since publication, as I will be conducting continuing education based in part on the classic text, first in the reference list, "Langa's Relative Analgesia in Dental Practice."

In this text's preface, Langa makes the statement, "The term 'relative analgesia' was introduced by the author many years ago." This would seem to be a credible statement, given the length of time he had been teaching.

In Chapter 4, section subtitle "The Planes of Analgesia," Langa lists the four stages of anesthesia and has divided Stage 1 into three planes: the first two being degrees of Relative Analgesia, and the third being the plane of Total Analgesia. Langa provides clinical signs to determine which plane the patient is experiencing.

The reader is warned to avoid the third plane because of its proximity to Stage 2 of Anesthesia, the Excitement/Delerium Stage. Langa notes that attempts to maintain Total Analgesia often result in the patient drifting in-and-out of the Excitement stage, causing undesirable lapses in patient co-operation.

While individuals vary considerably in their response to varying concentrations of nitrous oxide, given the doses reported in the original article, it is likely that many, if not all, of the subjects were, in fact, quite beyond the stage of Relative Analgesia.

This is not to be critical of the practice described, as the safety of the technique was amply documented. Apparently it enabled needed treatment to proceed. It is furthermore likely the procedures performed did not require patient co-operation, and the patient was not expected to look forward to experiencing repeated sessions with nitrous oxide, administered in this manner.

In summary, using Langa's technique and definitions, the procedure used for the children was probably not equivalent to Relative Analgesia in its classical sense, as is administered in an outpatient dental setting by a trained operator. I believe it was within this context, however, that Langa was speaking, when he originally defined the term.

I do like the last two sentences of the author's reply and would like to use it verbatim with credit, in my continuing education presentation: "Nitrous oxide provides analgesia, anxiolysis, and mild amnesia obtained with maintenance of verbal contact and predominantly intact laryngeal reflexes. No other single agent does this."

We read with interest the article by Duncan et al (1) making us aware about the increasingly common household hazard of contact burns due to hair straighteners particularly in children. We would also like to share similar experience in our department of 2 cases who presented with contact burns from hair straighteners.

Case 1: 18 month old boy with superficial partial thickness burn over the palmar aspect of his left middle finger extending form the proximal interphalangeal crease till the pulp of the finger.

Case 2: 24 month old boy with superficial partial thickness burns over the palmar aspect of his left little finger from proximal interphalangeal crease till middle interphalangeal crease; ring finger from proximal interphalangeal crease till middle interphalangeal crease and hypothenar eminence of the same hand measuring 1cm× 1.2cm along with 2 large blisters.

In both the cases the mechanism was accidental contact and possibility of non-accidental injury was ruled out. Both of the cases were managed conservatively, the blisters were left intact (2) and the wounds were covered with chlorhexidine acetate 0.5% (Bactigrass®) dressing. The burns in both the cases healed spontaneously without any residual scarring.

We completely agree with the authors that hair straighteners are becoming increasingly common potential hazard as more and more of such cases are reported. This preventable cause of childhood morbidity has not been well recognised. Since these burns are potentially avoidable the public need to be made aware by education and the manufacturing companies should compulsorily add a word of caution to “keep away from children” by legislation.

References:

1) Duncan RA, Waterson S, Beattie TF, Stewart K. Contact burns from hair straighteners: a new hazard in the home. Emerg. Med. J 2006;23;e21

2) Swain, AH, Azadian, BS, Wakeley, CJ, Shakespeare, PG. Management of blisters in minor burns; British Medical Journal 1987;295(6591);181

We read with interest the article written by Freshwater et. al. (1) 'Extending access to specialist services: the impact of an onsite helipad and analysis of the first 100 flights' and were very impressed with the findings and at the outset we would like to congratulate the authors on this innovative analysis. This paper demonstrates the great impact retrievals and transfers can have on the referred hospital, however we provide some constructive criticism on the article below.

Although this article is a first in investigating the success of a new helipad at the University Hospital Southampton (UHS), we feel that the authors have overlooked more updated and recent data on the number of missions flown annually in the UK. The Association of Air Ambulances' website, under the document '2013 Framework for A High Performing Air Ambulance(2)', states that 19 charity air ambulances flew approximately 25500 missions in 2012. This is considerably more than the 19,000 stated within the article. Following this, additional numbers of charities have been established, thus we feel that the total figures until the time this article was published will be far greater. This updated information would have only strengthened the findings of this study.

On a similar note, regarding 'blue-light' times vs normal speed drive times, a more recent article by McKeekin et. al. (3) states that whilst the software used is appropriate to estimate 'blue-light' times from normal speed drive times (as stated by the authors in the article), more importantly there needs to be adjustments made in the software to account for population density, traffic and other factors involved. This again is more recent evidence than that quoted by the authors in this paper (4) (5).

Due to the nature of this type of study, the results are quite subjective because it is human decision whether to send the patient via air to the hospital. That human is not always the same and changes per shift, and therefore there may be some times where patients were sent to UHS or alternative sites when others would not have made that decision. This can alter the results, and therefore for future studies, it is important to address this issue to ensure results are as accurate as possible. We appreciate that the sample size was small because the service was new, however we would suggest that in future, the data would be more accurate if a larger sample size is analysed over a greater period, by comparing with other trauma centres which have helipads. Also it is important to compare results internationally to better understand the findings in a national and international context. Finally, a discussion into the implications on the staff, resources and wards of the hospital since the introduction of the helipad would be equally important.

Once again, we commend the authors on a brilliant piece of work, and look forward to reading further articles exploring into this topic further.

1. Freshwater ES, Dickinson P, Crouch R, Deakin CD, Eynon CA. Extending access to specialist services: the impact of an onsite helipad and analysis of the first 100 flights. Emergency Medicine Journal. 2014;31:121-5.

2. Association of Air Ambulances. Framework for A High Performing Air Ambulance. 2013:9. Available from: http://www.associationofairambulances.co.uk/resources/events/AOAA- Framework%202013-OCT13-%20Final%20Document.pdf [Accessed on 13.04.2014]

3. McMeekin P, Gray J, Ford GA, Duckett J, Price CI. A comparison of actual versus predicted emergency ambulance journey times using generic Geographic Information System software. 2013;0:1-5.

4. Lerner EB, Billittier AS. Delay in ED arrival resulting from a remote helipad at a trauma center. Air Med J. 2000;19(4):134-6.

5. Hunt RC, Brown LH, Cabinum ES, Whitley TW, Prasad NH, Owens CF, Jr., et al. Is ambulance transport time with lights and siren faster than that without? Ann Emerg Med. 1995;25(4):507-11.

Conflict of Interest:

None declared

The principle of 'primum non nocere' stems from the ancient world of Plato. In the 'real' world it is immpossible to act without doing harm. An examination or treatment takes always some time and money from the patient. Taking time and money is the minimum harm that is done. In many cases ther is additional harm.

Therefore the principle 'doing more good than harm' seems at first sight a better and more realistic principle but unfortunately what is 'more good than harm' cannot be easily defined. Indeed, what is considered as more good than harm differs from individual to individual, from time to time, from society to society.

A diagnosis is not only a matter of knowing. The more that is known the more correct diagnoses will be made, but for an individual diagnosis it is ultimately a decision based on less or more firm knowledge, not on certainty. Who has the right (or the duty) to decide where uncertainty is the rule? Perhaps it is (partly) dependent on the circumstances. For many it will seem to be the first right of the well informed patient since he/she will suffer from the potential harms or profit from the potential benefits of the treatment. But even if this principle should be generally accepted there is often lack of time in urgent situations to inform the patient or the patient is not in the possibility to understand the information. Moreover the government and/or insurance companies too will influence the decision by less or more or no reimbursement for examinations and treatments.

Since it can be assumed that diagnoses are more often accurate with increasing knowledge it can perhaps be stated that doing more good than harm can be defined by the duty of making efforts by the individual as well as by the society to increase knowlegde.

Conflict of Interest:

None declared