The Triumphs and Pitfalls of Limited Access to Animals for Teaching Veterinary Surgery-The Murdoch University Experience
Rick Read, BVSc, PhD FACVSc,
Division of Veterinary and Biomedical Sciences, Murdoch University
Perth, Western Australia
The surgical instruction program for undergraduate students in the veterinary school at Murdoch University was originally designed in an environment with unlimited access to dog-pound derived unwanted dogs that were scheduled for euthanasia. In 1991, this situation suddenly changed due to pressure from sections of the public and from within the School. We currently have no access to dogs from pounds and shelters for any form of teaching activity, and this extends even to cadavers. We continue to have access to greyhound cadavers, many of which are shared with anatomy and these are used predominantly for revision of surgical anatomy, but also for basic orthopaedic instruction.
The restricted access to dogs has stimulated major changes in the undergraduate teaching programs in surgery and anaesthesia. The students now develop basic surgical dexterity skills using inanimate objects-suturing foam rubber models has been found to be an excellent way to develop instrument handling skills and practice suture patterns and knot tying. Students are now much more competent and confident when they approach the task of suturing their first live patient.
It has always been a goal of our surgical instruction program to emphasise the privilege students have in being allowed to practice surgery on animals. We also aim to minimise the number of animals used and therefore need to maximise the benefit in terms of instruction from each class. When considering the use of live animals, the benefits to the teaching of both surgery and anaesthesia need to be evaluated. With no access to dogs or cats, the teaching program now uses young pigs purchased at market as the basic surgical instruction model. Students work in groups of 3 and alternate in the roles of surgeon, assistant surgeon and anaesthetist. Anaesthesia staff supervise and instruct the student anaesthetists and surgical faculty instruct the students in basic techniques but also emphasising the anatomical and physiological differences between pigs and the more usual surgical patients such as dogs and cats. All animals are closely monitored throughout the time of anaesthesia and a full anaesthetic clinical record is maintained and submitted by the student for assessment.
Throughout first semester of the fourth year of the curriculum, the students perform exploratory laparotomy on pigs under general anaesthesia, the animals being euthanased at the end of the procedure while still under general anaesthesia. The principles of pre-emptive analgesia are discussed with the students and the animals are placed on intravenous fluid maintenance therapy during the procedures. Each student performs the role of surgeon, assistant surgeon and anaesthetist on two occasions. The student surgeon prepares in advance for the class in consultation with the other members of the team and chooses the surgical procedures to be incorporated into the exploratory laparotomy for his/her group. Gastrointestinal tract, urinary tract and parenchymatous organ procedures are commonly undertaken in addition to neutering and developing the technique for gaining access to and handling the various abdominal organs. Student surgeons write a full surgical report which is submitted for assessment.
These laparotomy classes provide experience in handling live animals, induction and maintenance of general anaesthesia, endotracheal intubation, handling live organs, haemostasis, tissue suturing and understanding and coping with unexpected surgical problems that occur intraoperatively. Formal teaching assessment of this course and observation of the skills of the student participants give the staff confidence that the students' skills and ability progress significantly and rapidly through the course of these laboratory classes.
Second semester laboratory classes extend to other procedures including thoracotomy (using pigs) and orthopaedic surgical approaches to the hip and stifle joints (using greyhound cadavers or mature sheep). Thoracotomy classes provide important instruction in anaesthetic management of patients requiring intermittent positive pressure ventilation and experience for the surgeon in dealing with the constantly moving thoracic contents.
We have contemplated a cadaver donation program but it is not yet fully organised and is unlikely to provide a large source of cadavers for teaching.
Individual students with conscientious objection to participating in classes which involve the use of live animals for teaching are required to indicate this at the commencement of the teaching year. In such cases, the University has a policy which charges the students to work with the academic staff in constructing an alternative teaching program which will ensure that the teaching objectives of the course will be met. This usually involves the individual students spending additional time under the supervision of a registered veterinarian in private practice, documenting the number and types of cases in which they have participated in the clinical anaesthesia and surgery. At the end of each semester, their progress is assessed through a specifically constructed exercise using clinical case material to ensure that their level of competence in both anaesthesia and surgery is satisfactory.
Students successfully completing the laboratory class component of their surgery and anaesthesia curriculum are considered to be equipped to safely participate in the management of clinical cases through their clinical rotations in the final year of undergraduate study. Performing routine neutering procedures on dogs and cats under the supervision of academic staff forms a component of the small animals surgery and anaesthesia rotations during the final year of instruction.
The use of pigs and sheep where the procedures being taught are predominantly used in companion animals. The abdominal and thoracic anatomies are different which limits the clinical applicability of the procedures.
The sense of frustration that there are hundreds of unwanted dogs being euthanased each week in Australia and the potential benefit to our veterinary undergraduates from having access to either live dogs or fresh cadavers is lost
Individually tailored alternative programs to the laboratory classes for those with a conscientious objection are labour intensive
Students develop surgical dexterity skills initially through formal didactic instruction followed by classes on inanimate objects and then on live animals so that the number of animals required is minimised and the students derive maximum benefit from each animal used
Anaesthesia skills are able to be developed and refined through the use of live animals
Flexibility to provide for the needs of the small number of students who object to participation in classes using live animals for teaching
Undergraduate veterinary students at Murdoch University are well informed about the alternative approaches to surgical instruction that are used in other veterinary faculties. To some extent, this has been a result of the activities of a small number of students who believe strongly in this cause. The students remain very supportive of the current curriculum and are very aware of their privileged situation compared to students in many other veterinary institutions.
Alternatives to the use of live animals in teaching undergraduate level surgery and anaesthesia are frequently suggested and a number of published studies suggest that the use of live animals is not essential to the goal of producing a competent veterinarian who, immediately on graduation, can perform routine surgery and anaesthesia to the level required of a general veterinary practitioner. The teaching curriculum is under a process of constant review as we seek to introduce better teaching models and practices to our veterinary curriculum. Further development of the cadaver donation program through our teaching hospital and development of our relationship with animal shelters to provide an expanded neutering program are seen as primary goals for the next few years.