3. small Anim. Pract. Vol. 9, 1968, pp. 235 to 236. Pergamon Press Ltd. Printed in Great Britain

Clinical Communication : An Unusual Injury Sustained in a Dog Fight TREVOR TURNER 15 Mandeville Road, Northolt, Middlesex

Subject and history THE subject was an 8-year-old Miniature Poodle dog. The owner telephoned on a Sunday afternoon requesting attention. The animal had been attacked by a much larger dog, which had “gripped him by the throat and shaken him.” The owner had examined the Poodle immediately for wounds but had been unable to find any. In consequence, she had allowed the dog to walk home. On arrival home she had noticed that the left side of the dog’s neck appeared to be swelling and that the dog was “making snorting noises when he breathed.” When she touched the swelling, the dog bit her.

Symptoms and diagnosis On examination the dog appeared to be normal except for a very large swelling

on the left side of the neck, extending from the junction with the thorax up to the mandible. There appeared to be a small puncture wound on the left side midway along the neck from which blood was oozing. The animal resented this area being touched. A tentative diagnosis of haematoma was made and it was decided to incise over the swelling, under local anaesthesia and to locate the bleeding vessels.

Treatment Using 2 % Xylocaine and Adrenaline*, the area was anaesthetised by local

infiltration and an incision approximately 1 in. long was made over the site extending from the puncture wound caudally. Immediately a large clot was expressed followed by the common carotid artery which had been completely severed. Blood was pouring freely from the cardiac portion of the severed vessel. Realising that repair was likely to be more prolonged than had been originally thought, the vessel was clamped and the animal was anaesthetised using Thiopentone Sodium7 (Intraval). The dog was intubated using a cuffed McGill tube and oxygen was administered on open circuit.

*Xylocaine 2% with Adrenaline, Astra Hewlett Ltd. thtraval, May & Baker Ltd.

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236 T. TURNER

The incision was extended some 2 in anteriorly and a search was made for the cephalic portion of the artery. The overlying sternomastoid and sternohyoid muscles appeared badly bruised and lacerated in parts. The carotid sheath which encloses the carotid artery and the jugular vein, together with the vago-sympathetic trunk on that side appeared to consist of one huge haematoma but as far as could be ascertained, the jugular vein was still intact. The vagal nerve trunk could not be found.

The anterior portion of the carotid artery was found to have retracted some 16 in. and it was impossible to bring the two ends into apposition. In consequence any attempt at artery repair was abandoned and both ends of the severed artery were ligated using 3/0 chromic catgut.$ Two or three sutures were placed in the lacerated overlying muscles and the wound was then liberally dusted with penicillin and sulphamezathines powder and the skin edges brought together using 0.30 mm sheathed multifilament nylon material.** A light pressure pad was applied and the wound was bandaged and the animal given 500,000 i.u. Penicillin Gt t daily for 5 days. The owner was given a particularly guarded prognosis in view of the damage sustained by the artery and presumably the adjacent nerve trunk. Recovery, however, was uneventful. Sutures were removed from the skin after 7 days and examination of the animal after 14 days revealed no abnormality.

DISCUSSION According to Miller,$$ the left common carotid artery is the main arterial supply

to the left side of the head and also to the brain. Collateral branches are very small in the dog and consist of the anterior and posterior thyroid arteries which anastomose just posterior to the thyroid gland and arise cranially and caudally from the common carotid artery. Since they are quite small I was concerned that they might not be able to maintain an adequate collateral circulation particularly immediately after the accident and therefore examined the animal carefully and regularly for any signs of ishcaemia involving the head or the brain. On examination there were none. A fairly diligent search had been carried out for the vago sympathetic trunk at the site of the injury. Although the jugular vein could be located without too much difficulty, the nerve trunk was not located. Most of the structures had been obscured by blood and it is possible that the nerve tract was intact and had been missed. However, in view of the fact that it could not be located the owner was warned that there might be digestive and/or cardiac disturbance but again, none appeared on examination. Further examination 6 months after the injury revealed no abnormality.

:3/0 chromic catgut, Braun. §Penicillin G with sterilised sulphamezathane, I.C.I. Ltd.

**Armourfil 3/0 Armour Pharmaceutical Co. ttcrystapen, Glaxo Laboratories Ltd. $$Miller, Anatomy of the Dog, W. B. Saunden.