CHAPTER IV.. Diseases of Blood-Vessels.

DISEASES OF BLOOD-VESSELS.

Diseases of vessels, arteries or veins, in animals of the bovine and ovine species are frequently nothing more than localisations of grave general disorders, and rarely admit of treatment. This is specially the case in regard to arteries, but a study of the diseases of veins has some practical importance.

PHLEBITIS.

Phlebitis, i.e., inflammation of a vein, is of interest only in the case of bovine animals. In them certain conditions may occur which the practitioner should understand, with a view either to prevention or treatment. Inflammation of the veins may be due to external causes, such as surgical or accidental wounds (phlebotomy wounds, accidental wounds, local inflammations, etc.), or to internal causes of infectious origin (general infection, puerperal infection, etc.).

ACCIDENTAL PHLEBITIS.

The jugular vein may become inflamed as a result of accidental wounds or of phlebotomy, but the mammary vein in cows is much more frequently affected. In both cases the disease is due to infection of the clot which seals the vessel; it may assume the form of either adhesive phlebitis or suppurative phlebitis. Whether produced directly by the use of infected instruments or whether it is of a secondary character, traceable to the clot being infected by germs entering from without being conveyed to the wounds by the head-stall chains, by litter, manure, etc., the result is the same. The inflammation, at first confined to the endothelium, extends to the wall of the vein and causes fibrin to be precipitated over the inner wall of the inflamed vein for a distance varying with each case.

If the microorganisms do not produce suppuration, the vein appears simply thrombosed and inflamed, the phlebitis remains of an adhesive character, and may disappear spontaneously, provided the animal be kept quiet. If, on the other hand, suppuration is set up, the clot gradually breaks down, the internal surface of the vein develops granulations and undergoes suppuration, and the phlebitis is then said to become suppurative. The clot may even become entirely detached, transforming the suppurative phlebitis into a very grave form of hæmorrhagic phlebitis.

The jugular is the commonest seat of adhesive phlebitis, the mammary vein of suppurative phlebitis.

=Symptoms.= The symptoms are easy to recognise. The accidental or instrumental wound is the seat of a painful œdematous swelling. It discharges a reddish offensive serosity, or exhibits blackish-violet bleeding granulations surrounding a little central sinus.

The affected vein, whether the jugular or mammary, soon becomes swollen, is sensitive to the touch and very rapidly becomes indurated in the direction of its origin for a greater or less distance.

Phlebitis has then set in, and according as one or other complication predominates, it is described as suppurative or hæmorrhagic.

=Diagnosis and prognosis.= The diagnosis presents no difficulty. In phlebitis of the jugular the neck is held stiffly, and the jugular furrow is partly obliterated.

The prognosis is somewhat serious, particularly in phlebitis of the mammary vein, for obliteration of the vein interferes with the function of the venous plexus from which it springs, and, although there may be a limited vicarious circulation, the secretion of milk is indirectly and secondarily checked owing to difficulty of irrigation.

The extension of phlebitis of the jugular towards the head and the venous sinuses of the cranial cavity, is quite exceptional.

When the mammary vein is inflamed it appears collapsed in the direction of the heart and swollen, indurated, and painful in that of its origin in the mammary gland.

=Treatment.= The first point requiring attention is so to fix the animal as to prevent the clot from being pressed upon or crushed, though, unfortunately, this cannot always be properly done. The difficulty is obviated by applying vesicants, which cause swelling and pain, and so reduce natural movement of the parts to a minimum.

At first, when the parts surrounding the operative wound are simply swollen and phlebitis is threatened, repeated application of tincture of iodine or a liquid vesicant is useful, and may prevent the disease developing.

In existing cases a blister applied over and around the whole of the hardened tract may prevent the mischief from proceeding beyond the adhesive stage. In such case the clot becomes organised, the vein remains obliterated, and recovery follows.

Similar treatment may also be employed in suppurative phlebitis, but as the clot gradually breaks down in consequence of the action of bacteria it is useful and almost indispensable to disinfect the vessel. For this purpose the opening of the sinus must be enlarged, and, by means of a sterilised or very clean syringe with a curved nozzle, the parts washed out daily with warm boiled water, followed by an antiseptic injection containing 2 per thousand of iodine, 3 per cent. of carbolic acid, or, better still, glycerine containing 1 per thousand of sublimate.

If in spite of this treatment the phlebitis extends towards the origin of the jugular or mammary vein, a counter-opening may be made at the point where the clot still remains adherent, and a strip of iodoform gauze saturated with tincture of iodine or with blistering ointment diluted to one-eighth with oil may be passed. Needle firing is also of value. Finally, as a last resource, a ligature may be applied to the vein above or beyond the clot.

This operation, which in the horse is confined to hæmorrhagic phlebitis, is especially applicable to phlebitis of the mammary vein in the cow. As the vein is subcutaneous, the operation may easily be performed in the standing position; the successive stages are as follows:—

The patient is firmly secured and its hind limbs hobbled by passing a rope around the hocks in a figure of eight. It is steadied on one side by an assistant who presses on the quarter.

One cubic centimètre of a 10 per cent. solution of cocaine is subcutaneously injected on each side of the vein at the point chosen. Ten minutes later a button-hole incision is made through the skin and a loop of thick catgut passed around the vein by means of a curved needle. The ligature is tied firmly with a surgical knot and the little wound afterwards covered with a mass of cotton wool secured by collodion.

INTERNAL INFECTIOUS PHLEBITIS (UTERO-OVARIAN PHLEBITIS).

The internal forms of phlebitis of parasitic or infectious origin are as yet little understood, but mention may be made of phlebitis of the utero-ovarian veins which frequently follows parturition and post-partum infection. This is probably in many instances the real cause of the post-partum paraplegia without gross or apparent material lesions.

This form of infectious phlebitis may extend to the large internal and external iliac veins and produce embolism and septicæmia, as is shown by recorded cases.

The mechanism of the disease is easily understood. The infective agents penetrate the veins of the uterine mucous membrane and pass from the lumen into the wall of the vein. Here they cause inflammation of the vascular endothelium, followed by the deposit of a fibrous clot of cylindrical form, which sets up partial thrombosis of the vein. This thrombosis becomes complete by the formation of a central clot due to venous stasis.

It is not necessary for the germs to penetrate at a number of points. The thrombosis progresses until it gains a large trunk beyond the original point of infection.

=Symptoms.= Phlebitis of the veins of the pelvis is frequently misunderstood or overlooked, because the practitioner is apt to confine his attention to external signs, the paresis and paraplegia of the hind quarters.

The symptoms usually appear from five to eight days after normal parturition or parturition in which there is retention of the after-birth followed by metritis. The animals show fever and lose appetite, signs which may be due to metritis, but soon after they experience difficulty in rising, and some days later remain permanently recumbent.

The circulation is weak, and the entire intra-pelvic region painful; the large nervous trunks are affected, exertion becomes difficult, and the animals refuse to rise. At this stage they should not be forced to do so.

In two to three weeks improvement may occur and lead to recovery but in many instances various complications in the nature of purulent infection or septicæmia set in, or the animals are previously slaughtered.

=Diagnosis.= The diagnosis can only be determined after the symptoms develop. Confirmation might in some cases be obtained by rectal exploration made methodically and gently.

=Prognosis.= The prognosis is grave.

=Treatment.= Treatment should be based on disinfection of the uterus by injections of boiled water or warm iodised solutions and drainage by means of strips of iodoform gauze. The animals should be placed on a thick and scrupulously clean bed, and as far as possible be spared any considerable exertion for a fortnight. By changing their position once or twice a day complications may be avoided.

UMBILICAL PHLEBITIS OF NEW-BORN ANIMALS.

One of the most serious conditions met with in practice is that known as umbilical phlebitis of new-born animals. Whilst in fact it is easy to deal with phlebitis of the jugular or mammary vein, surgical or medical assistance becomes extremely difficult in this case, because the inflamed vein is deeply situated in the abdomen and passes through one of the most important internal organs, viz., the liver. When it is added that umbilical phlebitis is in 95 per cent. of cases of a suppurative character, the reader may form some idea of its gravity.

Unless the condition is early diagnosed and measures are at once taken, such complications as infectious hepatitis, purulent infection, and septicæmia cannot be avoided. Death is then inevitable.

In order clearly to understand this phlebitis, however, it is necessary to recall the anatomical formation of the umbilical region in the new-born animal.

At birth the umbilical cord is represented by a cylindrical mass, surrounded by the terminal portion of the amnion. It enters the abdomen through a circular perforation in the abdominal wall known as the umbilical ring. This ring may be divided into two parts, one deeply seated, the fibro-aponeurotic ring, consisting of an aperture in the white line; the other the superficial or cutaneous ring, formed by the skin, which is wrinkled all round it, and constitutes a kind of sleeve about an inch in length. This cutaneous sleeve is continuous with the amniotic tissues. The entire umbilical cord is therefore enveloped in an amniotic-cutaneous sheath.

It is composed of four principal structures—the umbilical arteries, the umbilical vein, the urachus, and the interstitial mucous tissue.

The umbilical arteries and vein consist of two parts—the extra-fœtal part, which co-operates in forming the cord, and the intra-fœtal part.

The first is formed of two arteries and two veins, in contra-distinction to the condition in solipeds, where the cord only contains one vein. In the second, the arrangement is as follows: The two umbilical allantoid arteries on entering the abdomen curve backwards towards the entry of the pelvis, passing over the sides of the bladder enveloped in the lateral ligaments, and extend upwards towards the bifurcation of the aorta, finally pouring their contents into the internal iliac arteries. In the adult they may still be traced as annexes of these latter vessels. The two umbilical veins on passing through the ring unite to form one within the abdomen. This vessel passes forwards, rising along the lower abdominal wall, then becomes lodged in the thickness of the inferior middle ligament of the liver, and finally penetrates that organ where it unites with the portal vein. It is also connected with a vessel known as “the vein of Arantius,” which places it in communication with the posterior vena cava, a vein not found in solipeds.

The fœtal blood is purified by exchanges between it and that circulating in the maternal placenta, and when re-arterialised it returns by the umbilical vein.

The urachus, found in the embryo and fœtus, eventually gives rise to the bladder. In new-born animals this viscus is therefore open at its base, and communicates with the allantoid cavity through the urachus. The urachus starts from the base of the bladder, and, extending along the median plane of the lower abdominal wall between the two umbilical arteries as far as the umbilical opening, takes its place in the cord alongside the vessels. Through it the secretions of the fœtal kidneys drain into the allantoid cavity. The interstitial mucous tissue, also called “Wharton’s jelly,” is a gelatinous material which unites these different vessels and helps to support and protect them in the umbilical cord. It is particularly abundant opposite the umbilicus.

Immediately after birth the umbilical cord ruptures of itself as a result of the fall which the young animal experiences or of movements made by the mother, as for instance when she attempts to rise. In certain other cases it is divided by the mother biting it, or it may be ligatured by some person present. However the rupture may be brought about, it always occurs at a distance of 2 to 4 inches from the umbilicus. The immediate result is to produce thrombosis of the umbilical vessels and obstruction of the urachus. The two umbilical arteries rarely bleed, for hæmostasis is brought about by stretching, and these arteries, being very elastic, almost immediately retract and close. The umbilical veins simultaneously become blocked, and the single intra-abdominal vein having no further raison d’être, gradually becomes obliterated. The urachus should normally be obliterated at the moment of delivery (Colin and Saint-Cyr), or at any rate soon afterwards, as a consequence of rupture of the cord (Chauveau and Zundel).

Immediately after delivery another change sets in. The extra-fœtal portion of the cord, which remains attached to the umbilicus, dries on contact with the air, the Wharton’s jelly retracts, the whole undergoes a kind of necrosis, assumes the appearance of a dry scab, and in eight or ten days falls away, leaving in its place the umbilicus, which should be half cicatrised on the fall of the cord. Thus the umbilical cord presents an extra-fœtal degenerated portion and a persistent portion about ½ to 1 inch only in length, buried in the cutaneous ring of the umbilical region.

If all the changes indicated occur normally and physiologically, the little wound in the region of the umbilicus cicatrises in a perfectly regular way. But unfortunately this is not always the case. At times the cicatrix becomes contaminated by manure, urine or dust, suppurates, and may then become the seat of various complications, such as umbilical phlebitis, omphalitis or persistence of the canal of the urachus.

UMBILICAL PHLEBITIS OR OMPHALO-PHLEBITIS.

=History.= Umbilical phlebitis, and in a more general sense all pathological conditions of the umbilicus, in new-born animals have been the object of numerous investigations by Lecoq, Bénard, Loiset (1843), Bollinger (1874); and more recently by Morot (1884), Uffredizzi (1884), Chassaing (1886), etc.

Omphalo-phlebitis may occur as a primary condition or may appear as a complication of omphalitis and of persistence of the urachus. It consists essentially in suppurating inflammation of the umbilical vein, but is not infrequently accompanied by omphalitis, arteritis, peritonitis, and cystitis.

=Causation.= The disease results from infection of the (normal) clot and of the wound resulting from severance of the cord. The infection may only cause simple phlebitis of the umbilical vein, but if the organisms are virulent the phlebitis almost inevitably degenerates into suppurative phlebitis.

Formerly omphalo-phlebitis was thought to be caused by the mother licking the foal, by irregular tearing of the cord, by crushing and separation of the obliterating clot, etc. The truth is that all these causes favour infection of the umbilical wound, which is the primary cause, suppurative phlebitis being secondary only.

When the cord is ruptured both the veins and arteries become plugged, and bleeding ceases. This plugging should end in organisation of the clot and obliteration of the vessels. If, however, the wound is infected, microorganisms make their way between the clot and walls, and extend along the inner surface of the vein, infecting first the clot and then the vein, and thus setting up suppurative phlebitis.

If suppuration does not continue, recovery may occur spontaneously. Infection may be confined to the clot, producing simple phlebitis, but it often extends along the umbilical vein to the liver, causes infectious hepatitis and purulent infection or septicæmia. Similar results may be produced by infection of the arteries, the organisms making their way as far as the bifurcation of the aorta, and thus gaining the general circulation. Moussu believes that this is the commonest method by which septicæmia is produced in calves.

=Symptoms.= In these cases it is usually the general symptoms which first attract attention, the local lesion passing unnoticed for a greater or less time.

The animal shows intense fever, due to either suppurative phlebitis, infectious hepatitis, or, as often happens, to generalised infection. Appetite is lost, diarrhœa is abundant, the respiration and circulation are accelerated, and the temperature rises to 104° Fahr., or even 105° Fahr.

The local symptoms are those usually associated with omphalitis or phlebitis. An examination of the umbilical ring reveals an œdematous, hot, sensitive swelling, the lower part of which exhibits a chronic, suppurating, fungoid, blackish wound of unhealthy appearance.

This wound is the seat of one or more sinuses which penetrate the vein, arteries, or urachus. If only one sinus exists, it always passes upward and forward into the umbilical vein. The utmost precaution should be employed in examining the parts. Should it be thought desirable to probe the sinus in order to discover its direction, the probe must be very cautiously introduced, and only for a short distance, because rough handling would tear the tissues and carry infective material to deeper seated points.

=Complications.= These are numerous and very grave. Long ago Lecoq described a disease suggestive of laminitis, which beyond doubt was only a form of purulent infection. At a later date Loiset studied a disease following omphalitis, in which interstitial abscesses developed in the cord. This also was simply purulent infection.

More recently complications such as pleurisy, pneumonia, infectious endocarditis, diarrhœic enteritis, and especially suppurative polyarthritis of young animals have been referred to omphalo-phlebitis. All these complications result from infection. The microorganisms themselves or the toxins they secrete appear to have a particularly injurious action on the serous membranes, a fact which throws light on the frequency of such complications as pleurisy, peritonitis, endocarditis and arthritis.

Intoxication also plays a certain part, and microbic toxins are responsible, at least at first, for the uncontrollable diarrhœa, arthritis with sterile exudations, etc.

=Diagnosis.= This presents no difficulty. The alarming general symptoms seen at the outset immediately suggest in the case of young animals the possibility of disease in the umbilical region.

=Prognosis.= The prognosis is grave, it may be said very grave, because treatment is difficult to apply, and dangerous complications, which almost always prove fatal, may already have been set up.

One must always distinguish, however, and take into account in forming the prognosis, the special characteristics of the phlebitis, and weigh carefully the signs of complication. The fistula should be cautiously explored, and its depth, etc., noted, while the temperature, circulation, respiration, etc., should be carefully studied.

=Treatment.= A very important item of treatment consists in regularly and scrupulously cleansing the region of the umbilicus after the cord has separated and until the wound has completely cicatrised. The parts are washed with boiled water and dusted with boric acid, iodoform, etc.

A still better plan, and one that almost certainly guards against this disease, is to apply an antiseptic dry dressing as soon as the new-born animal has become dry. This need only consist of a small sheet of antiseptic cotton wool fixed to the umbilicus by four pitch bandages or by two pieces of webbing passed over the back. In this way contamination of the cord and the risk of infection are avoided.

In cases of fully-developed phlebitis the old generation of practitioners used to recommend local dressings with adhesive plasters, astringent and vesicant applications, etc. All such methods are useless, because they only act on a part of the diseased structures and cannot reach the blind ends of the sinuses. The classic treatment of suppurative phlebitis also is out of the question.

All that can be done, therefore, is slightly to open up the sinuses and wash them out frequently with antiseptic solutions, such as boiled water, sublimate glycerine, carbolic glycerine, etc., afterwards applying antiseptic dressings. These methods, however, are scarcely likely to put an end to infectious complications such as suppurative polyarthritis.

There is no danger in using strong carbolic solution, 3 per cent. creolin, 4 per cent. chloride of zinc, sulphate of copper, etc. Should there be several sinuses and should one of them extend in a backward direction, it is necessary to make certain that no communication exists between the urachus and the bladder. For this purpose some boiled water may be injected into the sinus. If a communication exist, this water will fill the bladder and distend the urachus. The treatment necessary in this case is similar to that of persistence of the urachus.

It is well in all cases to be guided by the following principle: never to resort to treatment unless suppuration has occurred and the sinus is blind. To check suppuration a blister may be applied around the umbilical region while means are taken to prevent the animal licking the parts.

Chassaing in 1886 suggested a rather original method of operation which deserves description. It is founded on the permanent treatment of sinuses, and consists in introducing a flexible osier stick, a kind of bougie, enveloped in tow and moistened with the following mixture:

Collodion 3 parts. Sublimate 1 part.

This is introduced for a distance of 3 to 4 inches into the fistula, and is fixed to the skin with gutta-percha or pitch. The dressing is renewed every five or six days, and healing takes place, it is said, in one, two, or at most three weeks.

It is very likely that if the sinuses were previously cleared and simply plugged with antiseptics or treated by introducing pencils of salol, nitrate of silver, sulphate of copper, iodoform, etc., at least as good results might be obtained.