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Biomedical subjects

C L Witte

Publications and source records attributed to C L Witte.

At least 127 records · Page 7Linked to original sources
PubMed1976

Ischemic therapy in thrombocytopenia from hypersplenism.

Percutaneous transfemoral arterial balloon occlusion or gelatin sponge embolization of the splenic artery or both were carried out in three high-risk patients with hepatic cirrhosis to reduce splenic hyperfunction and improve severe thrombocytopenia. Although this maneuver raised peripheral platelet counts in each patient, in one patient left upper quadrant pain with splinting of the lower chest cage led to hypostatic lower lobe pneumonia, while in another septic splentitis with gas-forming organisms necessitated splecectomy. Transfemoral occlusion of the splenic artery, although an effective, noninvasive approach to control splenic hyperfunction, has at the same time potential dangers that should be viewed with extreme caution in therapeutic application.

Adult↗
PubMed1976

Relationship of splanchnic blood flow and portal venous resistance to elevated portal pressure in the dog.

To determine the relationship of splanchnic blood flow and portal venous resistance to elevated portal pressure, in situ perfusion of the splanchnic circuit was carried out in 12 freshly killed dogs at varying perfusion rates and degrees of acute and chronic portal vein constriction. In six normal dogs before being killed, portal pressure averaged 8-8 +/- 1-2 mmHg and portal flow 658 +/- 81 ml/min. In the absence of portal vein constriction, increasing splanchnic perfusion to 1800 ml/min, minimally raised portal pressure (12-8 +/- 1-5 mmHg). With progressive acute constriction of the portal vein, however, comparable perfusion rates lead to progressively higher portal pressure levels and with greater than 90% constriction, portal pressure was greater than 30 mmHg with minimal elevation in splanchnic flow rate. In six other dogs before being killed but live to nine weeks after placement of an ameroid constrictor on the portal vein, portal pressure averaged 13-6 +/- 1-4 mmHg or slightly higher than in normal dogs (P greater than 0-02). Mesenteric venography and necropsy findings uniformly demonstrated 90% occlusion of the portal vein with extensive portasystemic collateralization. With increased perfusion of the splanchnic bed, portal pressure rose rapidly to approximately 35 mmHg with a flow rate of 1 800 ml/min.. These data suggest that, in disorders where resistance to transhepatic portal flow is marked, a small increment in splanchnic blood flow, which normally exerts little or no influence on portal pressure, promotes profound portal hypertension and may account for spontaneous 'rupture' of oesophageal varices. On the other hand, where resistance to transhepatic portal flow is mild but splanchnic blood flow is markedly hyperdynamic, reducing inflow may be sufficient to ameliorate extreme portal hypertension and its sequelae.

Animals↗
PubMed1976

Splenic artery ligation in selected patients with hepatic cirrhosis and in Sprague-Dawley rats.

The effects of splenic artery ligation were studied in Sprague-Dawley rats and in eight selected symptomatic patients with hepatic cirrhosis. In rats, this maneuver induced splenic infarction, reduced functional splenic mass, transiently raised platelet and reticulocyte counts and was without local complications. In seven selected patients with cirrhosis and prominent splenomegaly, the splenic artery was markedly enlarged, splenic arterial flow was greatly increased and splenic artery ligation partially lowered portal pressure. In three patients with varying cytopenias secondary to hypersplenism splenic artery ligation uniformly improved peripheral blood elements, although varying degrees of hypersplenism later recurred necessitating splenectomy in one. In five other patients, splenic artery ligation in conjunction with coronary vein ligation in four was performed for bleeding esophageal varices. Two patients later required portacaval shunting, and one other in whom operation was undertaken in desperation died of hepatic failure. Celiac-mesenteric arterioportography, operative portography, hemodynamic measurements and examination of peripheral blood elements in these eight patients suggests that splenic artery ligation in conjunction, where appropriate, with coronary vein ligation has several potentially beneficial effects. Hypersplenism may be sufficiently controlled to alleviate clinical symptoms. Arterial inflow into the portal system is reduced tending to lower portal pressure. Transheptic portal flow from the mesenteric bed is preserved. Venous anastomotic channels still functioning around the splenic pedicle and no longer draining a hyperdynamic splenic circuit may be converted into an escape route for mesenteric venous blood entering the portal system under high pressure. Nonetheless, each of these effects and their interrelationships require further study before this operation assumes a larger role in the treatment of complications of portal hypertension.

Animals↗
PubMed1976

Splenic artery ligation in experimental hypersplenism.

The effects of splenic artery ligation (SAL) were examined in Sprague-Dawley rats with methyl-cellulose-induced hypersplenism. When performed close to the splenic hilium, SAL effectively reduced functioning splenic mass and raised peripheral counts of leukocytes and platelets, a response similar to that following total splenectomy. In hypersplenism, therefore, a satisfactory hematologic response may not necessary require total ablation of the spleen but merely substantial reduction of functioning splenic tissue.

Animals↗
PubMed1975

Protein content of liver lymph in patients with portal hypertension secondary to hepatic cirrhosis.

Protein content of liver lymph was measured in 14 patients with portal hypertension secondary to advanced hepatic cirrhosis. An abnormally low concentration was found in each patient, averaging 52% of plasma levels. This finding reflects a decreased sinusoidal permeability to protein, the possible effect of "capillarization of the sinusoid" and may bear on development of portal congestion.

Adult↗
PubMed1975

Vascular spider: a cutaneous manifestation of hyperdynamic blood flow in hepatic cirrhosis.

Arteriography and gas analysis of blood aspirated from a vascular spider in a patient with hepatic cirrhosis were done before excision and histologic examination of the lesion. This study supports earlier work suggesting that a spider angioma is a cutaneous manifestation of a generalized hyperdynamic circulation in hepatic cirrhosis. Moreover, based upon a variety of experimental and clinical observations on the splanchnic circulation in cirrhosis, it is suggested that the portal hypertension blood flow encounters the obstacle posed by the scarred liver ("active congestion").

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