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The science of surgery is constantly evolving, based on an ever increasing and challenging research base. Readers will be aware of the increasing proportion of papers published in this journal reporting clinical trials, the results of which may quickly translate into surgical practice. However, it would be wrong to overlook the important contributions that have been, and continue to be, made in surgical research by experimental studies involving animals. Although the results may take time to translate into clinical practice, there can be no disputing that progress in areas such as organ transplantation, prosthetic materials and, more recently, immunotherapeutics are all the result of animal studies.

The accurate and complete reporting of surgical research underpins the veracity of the research and reflects the ethical standards of this journal. Moreover, it allows both reviewers and readers fully to comprehend the reason for the research, how it was conducted and the relevance of the results. With the expansion of clinical trials during the past decade there has been the development of guidelines for publication, most notably the Consolidated Standards of Reporting Trials (CONSORT), adopted by this journal in 2010. At the same time, the reporting of animal-based studies has come under scrutiny, with many papers published in peer-reviewed journals found to lack details in a number of areas, ranging from the description of the strain, weight and/or sex of animals, to a lack of clarity in experimental design and statistical analysis. More recently guidelines have been published under the acronym ARRIVE (Animal Research: Reporting In Vivo Experiments)[1]. These represent a checklist of what is suggested as ‘minimum information’ to be contained in any publication reporting research involving experimental animals, ranging from a description of the animals used and the procedures they were subjected to, through to details of outcomes as well as any adverse events. These guidelines have been adopted by a number of international journals as well as major funding bodies in the UK.

When reporting studies involving experimental surgery there is a need for a full description of the experimental procedures, including perioperative care. For both ethical and scientific reasons there is a need to prevent and/or alleviate pain in any experimental animal; furthermore, in many areas of the world there is a legal requirement to do so. Just as in human surgery, where there have been advances in pain control in recent years, the same is true in animals. It is now recognized that mammals, regardless of their size or position in the evolutionary tree, are able to experience pain[2].

It is, therefore, necessary in any publication reporting experimental surgery that authors clearly demonstrate that animals have been appropriately anaesthetized, and to do so researchers need to be aware of developments in the field of laboratory animal anaesthesia[3]; no longer can journals accept papers where there is evidence of inappropriate anaesthesia. Information is readily available in established texts, and researchers need to be aware that an anaesthetic regimen appropriate for human patients may not be so for animals. Monitoring of anaesthesia is also a necessary requirement during surgical procedures in the experimental animal, just as it is in humans.

Appropriate intraoperative care is a further point for consideration. Readers will all be aware of the special requirements for paediatric surgery; many of those requirements are applicable to the anaesthetized rat, weighing some 250 g. Prevention of hypothermia both during and after surgery is critical to ensuring homeostasis[4]; failure to do so will readily contribute to poor recovery, and with it poor experimental outcomes.

Perhaps the area most overlooked is that of analgesia. The ability of vertebrates to experience pain is now recognized from physiological studies, with these results influencing legislation controlling the use of animals in research in some countries[5]. There is no doubt that surgical procedures are painful; experimental studies have clearly demonstrated that a rat recovering from a laparotomy will experience pain that can be alleviated by analgesics[6]. Our knowledge of pain recognition and alleviation in animals has advanced considerably in recent years with the development of scoring systems based on objective measurements and assessments, such as weight change or locomotor activity, which have proven valuable in monitoring the response to analgesic administration[7]. Perhaps most illuminating in this area has been the clear demonstration that animals in pain will, if trained to discriminate between food types, self-medicate with analgesics to control either acute or chronic pain: an animal equivalent, perhaps, of patient-controlled analgesia[8]. Such systems can, however, rarely be applied as routine to animals and so there is an onus of responsibility on research workers to ensure that animals receive appropriate analgesia and that the response to this is monitored.

It is now over 10 years since the Journal of Bone and Joint Surgery stated that, if studies involving experimental animals were to be considered for publication, information regarding the management of postoperative pain had to be included in the paper[9]. Although journals will vary in their publication policy regarding animals used in research, any internationally ranked journal will wish to encourage publication of work that meets such high standards.

Just as surgery will advance, so will surgical research. Although the number of animals used in surgical research studies may be less than it was 50 years ago, there is a clear need to ensure that, where such studies do take place, they are undertaken to the highest standards of care; failure to demonstrate this may well lead to rejection of an article. The ARRIVE guidelines can provide a useful template for consideration in the planning and execution of surgical research involving animals. We should not, however, lose sight of ensuring that all involved in such studies adopt the attitude, succinctly summarized by Russell and Burch, of ‘humane experimental technique’[10].

Disclosure

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  3. References

The author declares no conflict of interest.

References

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  3. References
  • 1
    Kilkenny C, Browne WJ, Cuthill IC, Emerson M, Altman DG. Improving bioscience research reporting: the ARRIVE guidelines for reporting animal research. PLoS Biol 2010; 8: e100412.
  • 2
    McMillan FD. A world of hurts – is pain special? J Am Vet Med Assoc 2003; 223: 183186.
  • 3
    Flecknell PA. Laboratory Animal Anaesthesia (3rd edn). Academic Press: London, 2009.
  • 4
    Hall LW, Clarke KW, Trim CM. Veterinary Anaesthesia (10th edn). WB Saunders: London, 2001.
  • 5
    European Parliament. Directive 2010/63/EU of the European Parliament and of the Council of 22 September 2010 on the Protection of Animals Used for Scientific Purposes. http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri = OJ:L:2010:276:0033:0079:en:PDF [accessed 13 January 2013].
  • 6
    Roughan JV, Flecknell PA. Behaviour-based assessment of the duration of laparotomy-induced abdominal pain and the analgesic effects of carprofen and buprenorphine in rats. Behav Pharmacol 2004; 15: 461472.
  • 7
    Kohn DF, Martin TE, Foley PL, Morris TH, Swindle MM, Vogler GA et al.; ACLAM Task Force Members. Public statement: guidelines for the assessment and management of pain in rodents and rabbits. J Am Assoc Lab Anim Sci 2007; 46: 97108.
  • 8
    Colpaert FC, Tarayre JP, Alliaga M, Bruins Slot LA, Attal N, Koek W. Opiate self administration as a measure of chronic nociceptive pain in arthritic rats. Pain 2001; 91: 3345.
  • 9
    Management of postoperative pain in animals used in research. J Bone Joint Surg Am 1999; 81: 751.
  • 10
    Russell WMS, Burch RL. The Principles of Humane Experimental Technique. Methuen: London, 1959.