ABSTRACT: This case study will consider the anaesthetic considerations to bear in mind when repairing a mid-shaft femoral fracture in a gerbil using an intramedullary pin technique.

A one-year-old gerbil was presented with an injured hind limb after being accidently sat on by his six-year-old owner. Apart from an obvious injury to the leg, the gerbil appeared in good health. Clinical examination showed no new findings and confirmed the suspicion of a fractured hind limb (Figure 1). The owners were presented with several options, including euthanasia, but they were keen to pursue surgery.

Figure 1: Radiograph of fractured hind limb

Anaesthetic considerations

Small exotic species have an increased anaesthetic risk for a variety of reasons:

•   they are prone to hypothermia owing to their increased surface area in relation to their body volume

•   intubation in small species is often not possible or practical

•   small patients have a small circulating blood volume and, therefore, any fluid loss can cause severe compromise – for example, through respiration or haemorrhage

•   any restriction on the thorax can compromise respiration and so positioning must be carefully considered

•   in this particular species, the patient has no suitable site for pulse oximetry and surgical draping can interfere with monitoring.

Pre-operative preparations

Approximately 10 minutes prior to surgery, the patient was given warm intraperitoneal fluids (Hartmann’s Aquapharm 11). Buprenorphine was provided for peri-operative analgesia at 0.1mg/kg subcutaneously. This was given as a very small volume of a 1 in 10 dilution of the normal 0.3mg/kg solution.

The theatre was warmed to 29°C using the air conditioning unit. Heat loss was further addressed by using a combination of a space blanket, heat pad and bubble wrap (Figure 2). Space blankets are extremely useful for patients such as this and can be cut into a range of sizes to accommodate the individual patient.

Figure 2: Heat conservation

Induction and maintenance

Once the theatre had been prepared, the gerbil was placed inside a custom-built chamber and anaesthesia was induced using 3% isoflurane gas. The patient was then positioned on the table and anaesthesia was maintained at 2% via a T-piece circuit. A ‘finger’, cut from a rubber glove, was placed over the mouth of the T-piece and used as a face mask for the gerbil (Figure 3). The small hole in the glove finger minimised leakage and environmental contamination.

Figure 3: The improvised 'gerbil-sized' face mask

Surgery

The hind limb was clipped and prepped for surgery. Minimal fur was clipped off the surgical area and povidone iodine was used as the cleaning solution. The swabs used for ‘prepping’ were just damp enough to scrub the area. This prevented further heat loss by water evaporation during the procedure.

The surgery was approached laterally with a blunt dissection down to the fracture site. Several intramedullary pins were manufactured from sterile 25G and 23G 5/8" needles (Figure 4). These were cut to varying lengths using the radiographs as measurements.

Figure 4: Intramedullary pins were manufactured from sterile 25G and 23G 5/8" needles

A 25G pin was selected and advanced into the medullary canal of the distal femur. It was then inserted into the proximal end of the fracture and the fracture reduced. As the pin was a suitable size there was no rotation of the fracture site and the soft tissue provided a sufficient closing force. This was confirmed by a post-operative radiograph (Figure 5).

Figure 5: . Radiograph showing improvised intramedullary pin in place

The soft tissue was closed with 0.7m Polysorb and the skin was closed with intradermal sutures and skin glue. Recovery and surgery was deemed successful and the gerbil went on to enjoy 11 more months without further problems.

Study 2 – potentiated amoxycillin tablets

The subject of this study is potentiated amoxycillin palatable tablets (Synulox – Pfizer), an antibiotic with which every practice is familiar (Figure 2). The data are shown in Table 2.

Figure 2: Potentiated amoxycillin palatable tablets

The quantitative data have been obtained from the product data sheet, which has been written following a rigorous testing process in order to obtain a licence. The qualitative data have been obtained from interviews with veterinary nurses and veterinary surgeons using the tablets.

So which should you use?

As we have seen, both quantitative and qualitative data can prove very useful when considering any topic or research question that needs answering. Quantitative data give a positivistic, ‘black and white’ view of the world, whereas qualitative data are more descriptive and useful in different ways.

There is much debate between researchers about which approach is ‘best’, but in reality this depends on what needs to be discovered. Both give us answers, and both can give us more questions! The most important thing is that, when looking at any research finding, you consider how that conclusion has been reached – and don’t forget this can be done well or badly in either methodological approach!

However, this is an essential init
ial step in the process of deciding just how much you believe claims which are regularly presented to you as a professional, and how you are going to investigate important questions in your practice.

Author

Stan Livy bvm&s mrcvs

Stan graduated from Edinburgh in 2002. He currently works in general practice for the Goddard Veterinary Group in London with a large growing exotic caseload. Away from work he is a keen rower and Commonwealth medallist.

References

1.   GUNN-MOORE, D. A. and CAMERON, M. E. (2004) A pilot study using synthetic feline facial pheromone for the management of feline idiopathic cystitis. Journal of Feline Medicine anc Surgery 6:133-138.

2.   HAMILTON, L. (2007) Muck and Magic – cultural transformations in the world of farm animal veterinary surgeons. Ethnography 8:485-501

Further reading

BELL, J. (2005) Doing your research project. Oper University Press, Maidenhead HEK, G. and MOULE, P. (2006) Making sense of research – an introduction for health and social care practitioners. Sage, London.

GOLDACRE, B. (2009) Bad Science. Fourth Estate, London.

Veterinary Nursing Journal • VOL 25 • Noll • November 2010 •