Ischemic diseases of the large intestine.

The blood flow within the walls of the digestive tract must be sufficient to maintain its structural and functional integrity. All episodes of vascular insufficiency cause ischemic damage to the organ and carry the threat of diffuse or focal necrosis. Certain forms of ischemic colitis or proctitis arise from episodes of reduced peripheric or splanchnic blood flow; indeed, those which do not culminate in necrosis of the colonic wall are more frequently caused by hemodynamic disorders than by vascular occlusions. The crisis is often mitigated by the development of collateral circulation; this is, however, of rather poor quality so patients become very vulnerable to subsequent slight changes in cardiac output. Necrotic, gangrenous ischemic colitis arises from a combination of occlusive damage to the arteries and general hemodynamic disturbances. The vascular insufficiency may be slight or severe, temporary or long-lasting, localized or diffuse. In addition, the attack occurs in a septic medium in the presence of abundant microbial flora which may be highly pathologic. Thus infection complicates and aggravates the ischemic damage, resulting in the gangrenous aspect of the lesion tending to hide its ischemic origin. Indeed, the variability of the manifestations of the disease in one of its primary characteristics, and is a function of the different causative factors. A knowledge of the anatomy and pathophysiology of the splanchnic circulation and its hemodynamics is essential for a full appreciation of the diagnosis and treatment of the disorders, and for the adoption of the aggressive approach necessary to improve the poor prognosis of ischemic diseases of the colon and rectum. All treatment should be based on 1) constant, prolonged intensive care; 2) precise monitoring of any change in status; 3) rapid excision of any necrotic (often gangrenous) tissue. Ischemic colitis is most likely to occur in elderly patients with a history of cardiovascular disease, but can also affect younger individuals. It is a frequent, potentially lethal, entity. Although it can be classified as a separate disease on the basis of its clinical, radiological and anatomical characteristics, it is often confused with other disorders of the colon. Although the abdominal surgeon is most likely to be concerned with this disease, the vascular surgeon incising the lower aorta should always be on the look-out for segmentary ischemia of the distal colon which may occur following operation.

[Ischemic disorders of the large intestinal wall. Ischemic colitis and rectitis secondary to intrinsic vascular disorders]. / Les désordres des parois du gros intestin d'origine ischémique. Colites et rectites ischémiques, consécutives à des troubles vasculaires intrinsèques.

Ischaemic diseases of the large intestinal wall is a characteristic syndrome caused by vascular insufficiency of varying degrees. The ischaemia results from haemodynamic disturbances and often arises in spite of the patency of the vessels. The mucosa of the intestine is the tissue layer that is most vulnerable to ischaemia. Ischaemia of the colon occurs in the presence of a microbial flora that is often highly pathogenic, and hence the lesions rapidly become infected. For this reason the inflammatory features of the disease tend to conceal its vascular origin and ischaemic colitis has often been confused with other infectious, inflammatory, ulcero-haemorrhagic disorders of the large intestine. Although the syndrome may occur in any patient, it is much more common in elderly subjects with a history of arteriesclerosis and cardiac disease. Two main varieties can be identified, depending on the extent of the vascular insufficiency. In the first, the lesion may heal spontaneously or evolve towards fibrous strictures of the colonic wall; in the second, gangrenous necrosis of the colon or rectum may develope, the clinical picture of which has more in common with an "acute abdomen' than with ulcerative disease of the colon.

[Blood flow disorders of the colon and rectum and their therapy]. / Durchblutungsstörungen des Colons und Rectums und ihre Therapie.

Ischemic colitis or proctitis shows three evolutionary stages. a. complete recovery, b. fibrous stenosis, and c. acute ischemia leading to gangrene. The two first stages result more frequently from hemodynamic disorders than from vascular occlusions because, in the presence of the latter, collateral circulation develops. In addition, the colonic ischemia occurs in a septic medium in the presence of an abundant microbial flora which may be highly pathogenic.

Ischemic diseases of the large intestine.

The blood flow within the walls of the digestive tract must be sufficient to maintain its structural and functional integrity. All episodes of vascular insufficiency cause ischemic damage to the organ and carry the threat of diffuse or focal necrosis. Certain forms of ischemic colitis or proctitis arise from episodes of reduced peripheric or splanchnic blood flow; indeed, those that do not culminate in necorsis of the colonic wall are more frequently caused by hemodynamic disorders than by vascular occlusions. The crisis is often mitigated by the development of collateral circulation, which is nevertheless of rather meager quality, such that the patients are very vulnerable to subsequent slight changes in cardiac output. Necrotic, gangrenous ischemic colitis arises from a combination of occlusive damage to the arteries and general hemodynamic disturbances. The vascular insufficiency might be slight or severe, temporary or long-lasting, localized or diffuse. In addition, the attack occurs in a septic medium in the presence of an abundant microbial flora that may be highly pathogenic. Thus infection complicates and aggravates the ischemic damage, with the result that the gangrenous aspect of the lesions tends to hide their ischemic origin. Indeed, the variability of the manifestations of the disease represents one of its primary characteristics and is a function of the different causative factors. A knowledge of the anatomy and pathophysiology of the splanchnic circulation and its hemodynamics is essential for a full appreciation of the diagnosis and treatment of the disorders and for the adoption of the aggressive approach necessary to improve the poor prognosis of ischemic diseases of the colon and rectum. The salient points have been stressed in the present chapter. The features of the different forms of the disease have been described, together with the necessary medical treatment and the indications for surgical for surgical intervention. In the relatively rare cases where operation is necessary, the tactics and techniques have been described. All treatment should be based on (a) constant, prolonged intensive care; (b) precise monitoring of any change in status; and (c) rapid excision of any necrotic (often gangrenous) tissue. Ischemic colitis is most likely to occur in elderly patients with a history of cardiovascular disease, but it is not excluded in younger individuals. It is a frequent entity and is potentially lethal. Although its clinical, radiological, and anatomical characteristics permit its classification as a separate disease, it is often confused with other disorders of the colon. Although the abdominal surgeon is most likely to be concerned with this disease, the vascular surgeon who attacks the lower aorta should always be on the lookout for possible occurrences of segmentary ischemia of the distal colon as a result of his intervention.

[Bronchopulmonary hamartomas, chondromas, fibromas and myxomas]. / Bronchopulmonale Hamartome, Chondrome, Fibrome und Myxome.

The observation of 23 bronchopulmonary hamartomas, 9 chondromas, one fibroma and one myxoma has provided insight into the particularities of these tumors. The group of hamartomas, tumors of "erroneous mixture of tissue", included 20 cases which can be considered a malformation of the entodermal bronchial anlage, and 3 cases which can be regarded as a malformation of the mesenchymal anlage. The first type consists of multiple cleft-like spaces surrounded by ciliated and cuboidal epithelium. There are no alveolar cells. Cartilaginous, fibrous, myxomatous and lipomatous tissue and lymphocytes are also found. The second type consists mainly of undifferentiated mesenchymal cells with tubules, lined by cuboidal epithelial cells or an intestinal type of mucus-secreting epithelium. There may be some immature alveoli, but no ciliated epithelium is found. In contrast to the hamartomas, the chondromas are not derived from a dysontogenetic malformation of the bronchopulmonary tissue but are tumors which develop directly from the bronchial cartilage and are for this reason mainly localized in the endobronchial region. A special form seen in one case is association of pulmonary chondromas, gastric leiomyomas or leiosarcomas and extra-adrenal paraganglioma, though the latter is not always present.

[Bronchial and subpleural lipoma (author's transl)]. / Bronchiale und subpleurale Lipome.

Three cases of bronchopulmonary lipomas are reported, two sub pleural and one endobronchial. They represent 2,8% of all so-called benign bronchopulmonary tumours in our statistic. The two subpleural and asymptomatic lipomas were treated by thoracotomy and enucleation, the third, the endobronchial lipoma required lobectomy because of irreversible pulmonary damage.

[Bifocal bronchial granulocellular myoblastoma (Abrikosov's tumor)]. / Myoblastome granulo-cellulaire bronchique bifocal (tumeur d'Abrikossoff).

To the 44 observations of endobronchial granular cell myoblastoma described in the world literature can be added the case of a 52-year-old patient who presented with bifocal localization of this rare tumor of enigmatic origin. The two tumors were isolated from each other, one being situated at the level of the bronchus of the left superior lobe without implantation on the main bronchus, and the other at the bifurcation of the anterior segmental bronchus and left apico-dorsal segmental bronchus. The irreversible chronic-inflammatory peripheral lesions necessitated pneumonectomy. The patient is in excellent health 17 years after pneumonectomy. This is the fifth case of bifocal bronchial granular cell myoblastoma to be published.

[Bronchial carcinoids (author's transl)]. / Bronchialkarzinoide

Of 35 patients with bronchial carcinoids seen at the Kantonsspital Zürich during 16 years, 33 underwent an operative resection. The endoscopic resection is not recommended because of the risk of hemorrhage recurrence, and that this operation results in only partial removal of carcinoids which develop extrabronchially. It is concluded that bronchial carcinoids are potentially malignant tumours and that resection should be most radical if they show recurrence, invasive growth or metastases. Controls are necessary for a long period of time because even in presence of metastases the growth is very slow.

[Behcet's disease and toxic megacolon]. / Morbus Behçet und toxisches Megakolon

The gastrointestinal symptoms of Behçet's disease are ancillary manifestations of this disorder reflected principally in the form of diarrhea, abdominal pain, meteorism, nausea, and loss of appetite. If radiological changes can be detected they generally appear as dilatation of the small intestine or ulceration at different levels of the digestive tract. In our patient the intestinal symptoms started with dilation of the ileum and then toxic megacolon developed. At later follow-up examinations the radiological picture resembled Crohn's disease and ischemic colitis of the entire organ. It has been repeatedly, and wrongly, stated that there is an association between Behçet's disease and Crohn's disease or ulcerative colitis. Rather, it should be assumed that the intestinal manifestations of Behçet's disease correspond to those of Crohn's disease and ulcerative colitis without these diseases being actually present. The evolution towards toxic megacolon may be the consequence of a transmural infection across the colonic wall deriving from the mucosal ulcerations of colon and sigmoid, and proves that toxic megacolon is not a pecific complication of ulcerative colitis but may appear in the course of any acute inflammatory ulcerative lesion of the colonic wall.