Technique of the wound closure Practice Dorsal skin area of the sedated animal should be disinfected three times. After disinfection the operation area must be isolated by blanket with a hole in the centre. Parallel to the spine, cca. 1 cm far from it, a 3 – 4 cm long incision must be made on the skin. After bleeding attenuation (if it is necessary) the soft tissues, the muscle below the skin and the deep paravertebral muscle must be cut. After bleeding attenuation the wound must be closed streak by streak. Muscles and soft tissues should be sutured by multifilament thread using simple knots, the skin must be closed by monofilament thread by Donati or Allgöver knots. Preparation By preparation or dissection of tissues we can achieve better visualisation of the operation area and less trauma during operation. Otherwise when an organ or a part of an organ must be cut out, it should be separated from the surrounding tissues. Correct anatomic and surgical knowledge is needed by dissection and preparation. Sharp preparation Using scalpel Scalpels are used by homogenous tissues (mostly it is used by cutting the skin) and known anatomic relations. Cutting the skin if it is drawn perpendicular to the direction of the incision we can see better the deepness and direction of the incision. Incisions are placed in the line of least tissue tension provided this allows adequate exposure. The scalpel must be taken in the hand as if a fiddlestick or pencil. sharp preparation by scalpel with tissue’s perpendicular drawing Using scissors Preparation with scissor if the technique is trained does less harm. Using scissor we can also dissect sharp and dull. By dull dissection the scissor must be taken into the preparation’s area and after it the instrument can be closed and drawn from the area without closing it. In place of the scissor we can use also Pean or dissector. If we can see that there is no vessel or nerve in the dissecting area we can also cut it, or by taking into the area and pulling the opened scissor towards we can prepare along fibres. By this way we prepare sharp. a: dull preparation with scissor b: cutting process (sharp preparation) Electrocutes Using a.c. we can achieve dissection and bleeding diminishing at the same time. Dull preparation Dissection Soft tissues can be dissected carefully by finger. The other way by dissection preparing with scissor dull or sharp. By dull dissection the scissor must be taken into the preparation’s area and after it the instrument can be closed and drawn from the area without closing it. In place of the scissor we can use also Pean or dissector. If we can see that there is no vessel or nerve in the dissecting area we can also cut it, or by taking into the area and pulling the opened scissor towards we can prepare along fibres. By this way we prepare sharp. dull preparation with scissor coming along fibres dull preparation with opening the closed scissor in the dissecting area Membranous particles During the preparation we have to take care of the underlying tissues, because we don’t know if these tissues are connected each other. A loose wrinkle should be made with two claps or forcipes. If we open one of the instruments, the underlying structure separates if it is not connected. This procedure can be replayed with the other instrument. Finally between the two instruments the tissue can be cut with a scalpel or scissor. If a forceps is taken into the hole the adherences can be seen and higher care must be taken by the incision of the membrane. If there is no adherence, the membrane can cut through between the two legs of the forceps. By tense tissue or by adhesion wrinkle cannot be made, small superficial incisions should be made to avoid harming the underlying tissues. Adhesions must be released by finger or instrument. If there is a free area on the membrane it can be cut with scalpel or scissor. Very tense or hart tissues can be dissected or prepared using infiltration with physiological saline. By this way it becomes thicker and more transparent. preparation of membranous tissue; a: incision with scalpel, b: cutting with scissor Attenuation of bleeding Arteries Because their muscular wall the arterial bleeding stops within some minutes without any movement. But if the patient has arteriosclerosis, the arteries are not able to contract the bleeding will not stop. In this case catching the vessel with a Pean or Mosquito, and than making a ligature on it, the vessel can be closed. Artery lying under soft tissues should be stitched, avoiding from the ligature of other structures. At the end of the operation bleeding must be controlled once again. Veins If the vein draws back to the surrounding soft tissues, it is difficult to stop bleeding from vein. If bleeding is not stopped, huge haematomas can appear. To stop bleeding curved clamp must be taken onto the suspected area of the bleeding. The clamp should be kept on it minimum 5 minutes long. After removal of the instrument the haematoma must be controlled and in case of further bleeding the vein must be prepared and ligated. If the vein is located in the deep clamp mustn’t be taken on it because it is dangerous (organs or tissues can be harmed). In this case gauze plug should be taken until the bleeding stops. The plugs can be removed after 2 – 5 days. Big vein imbedded solid tissues cannot collapse. Their lumen must be clamped and after it closed with suture. By operations closed to central veins high care must be taken to avoid from air embolism. At the end of the operation bleeding must be controlled once again. Capillaries This kind of bleeding mostly stops when it is compressed or a blanket with hot saline is taken on it. If bleeding doesn’t stop the area should be compressed with a gauze and while it is drawn away from the operation area the small bleedings must be stopped with electrocutes or clamps or suture. Alternative techniques for stooping the bleeding: Sponge for stop bleeding Fibrin glue Seamed absorbable web or pad Seamed surrounding muscle or cauls