GENERAL DESIGN OF EXPERIMENTAL SURGERY
The steps involved in preparation include choosing the animal, administering anaesthesia, securing the animal’s position on the operating table, and cleaning the surgery environment.
26.11.1 Preperation of the Surgical Instruments
Surgical exposure involves cutting the skin using scissors or a scalpel. Generally, to prevent excessive bleeding, muscle bundles are divided by blunt dissection; however, in the case of the abdominal wall, the tendinous linea alba can be cut with scissors or a scalpel. Using bone forceps and a trephine, the skull is revealed.
Hemostasis, or stopping bleeding caused by cutting, can be achieved in a variety of ways depending on the kind of bleeding. For example:
• bleedings from capillaries can be mopped up;
• vessels can be temporarily constricted by artery forceps (such as Pean’s, Kocher’s, and mosquito forceps) to promote hemostasis;
• ligation, in which the only way to stop persistent bleeding is to pass a silk thread beneath the bleeding vessel, being cautious not to sever surrounding tissue;
• use of auxiliary materials, such as “fibrostan,” a sponge containing fibrin-like substance to encourage coagulation;
• application of bone wax, an aseptic surgical wax consisting of boiled beeswax and paraffin to the bone’s cut surface to halt bleeding;
• cauterisation, which is frequently employed in major operations to coagulate tissue proteins by high frequency alternate current flowing between the cautery’s small surface and a large reference electrode.
However, the very goal of some research is to avoid coagulation. It is possible to stop blood from clotting in blood samples or blood that has entered the tonometer’s cannula by applying citrate, which can bind Ca2 + ions, or heparin, a physiological anticoagulant.
26.11.2 Preparation
The anatomical region to be researched is made visible by removing or separating any surrounding tissues, if needed.
The principal arteries of the organ that has to be removed - the heart, for example - is cut between two ligatures. Connective tissue should be removed from vessels chosen for cannulation and nerves to be used for stimulation or recording. If required, the prepared area should be secured in place with a thread for any additional manipulation (e.g., ligation, pulling up, etc.). Similarly, sutures are used to fix electrodes or cannulas. Make sure the organ is not damaged or twisted.26.11.3 Postoperative Treatment
The animals are covered and brought to a warm chamber until they awaken following lengthy procedures. The administration of medications, including antibiotics, must be based on need. The animals should be fed light food on the first post-operative day before being gradually weaned back to regular diet. After the procedure is finished, collect and dispose of the debris. Following acute procedures, animals should be put to death with an aesthetic overdose and disposed of in accordance with the law. Washing and rearranging surgical tools, cannulas, dishes, and benches is recommended. The practical ends after all electrical equipment has been turned off, the workspace and surrounds have been cleaned.
26.12