Splanchnic metabolism associated with liver metastasis

Malignant melanoma with liver and spleen metastases: case report

CONTEXT

The diagnosis of primary melanoma is easily confirmed after histological analysis of the lesion, whereas it is rarely diagnosed when the patient even has distant metastases.

DESIGN

Case report

CASE REPORT

Malignant melanoma is responsible for about 1% of all deaths caused by cancer in the USA and only 3% of all malignant skin diseases. Malignant melanoma is a rare disease, although it corresponds to 65% of all deaths caused by skin cancer. The liver and spleen are rarely the first sites of melanoma metastases. This paper reports on the clinical picture of a patient with fatal malignant melanoma and hepatic and spleen metastases. As this was an un-usual presentation, the melanoma diagnosis could only be made after pathological analysis of the skin and hepatic lesions.

Acute fulminant lactic acidosis complicating metastatic cholangiocarcinoma

A patient with cholangiocarcinoma, metastatic to the liver and lungs, developed acute fulminant lactic acidosis in the absence of overt hepatic failure, sepsis, hypoxia, or circulatory failure. Despite extensive tumor replacement of hepatic parenchyma, no acid-base disorder was present during initial evaluation. The onset of acute lactic acidosis was temporally associated with the development of otherwise asymptomatic episodes of intermittent atrial arrhythmias. Once established, lactic acidosis was inexorably progressive, despite resolution of arrhythmias. Extensive areas of acute necrosis within the large hepatic metastases were demonstrated on postmortem examination, suggesting that local tissue ischemia, precipitated by cardiac arrhythmias, lead to excessive lactic acid production.

Development of a percutaneous fiberoptic hepatic venous localization catheter

OBJECTIVE

To develop a liver-specific biosensor system/catheter assembly that can be used to localize and cannulate the hepatic venous system without the need for fluoroscopic imaging. This would permit the bedside placement of a hepatic venous catheter for monitoring purposes without radiographic guidance.

DESIGN

Experimental, in vitro.

STUDY SETTING

Experimental laboratory at a university center.

SUBJECT

This was a simulation study to evaluate the ability of a cardiovascular monitoring catheter mounted with a liver-specific biosensor to anatomically identify a side arm tributary. The experimental system used for this study mimics the hepatic vein draining into the inferior vena cava and allows its localization without the need for assisted imaging. The biosensor design and catheter/sensor assembly function were studied in this in vitro model.

INTERVENTIONS

A liver-specific biosensor was developed by housing a homogeneous affinity fluorescence assay system sensitive to galactose in a microdialysis hollow fiber receptacle. A polyvinyl chloride tube containing a side arm was constructed to mimic the confluence of a venous tributary (i.e., the hepatic vein) with a major vascular channel (i.e., the vena cava). In this simulation, the side arm was continuously perfused with a liver-sensitive analyte (galactose) and the main channel was perfused with galactose-free buffer. A cardiovascular catheter containing a fiberoptic waveguide mounted with a galactose-sensitive fluorescent probe was advanced along the main conduit to assess its ability to identify the location of the galactose side arm infusion site.

MEASUREMENTS AND MAIN RESULTS

The response of the fiberoptic sensor to different galactose concentrations was assessed and found to be almost linear over the concentration range of 0 to 2 mM, which encompasses the expected utilization range of this system. The variability in identifying the galactose infusion point (simulated hepatic vein) in a 15-cm conduit was 1.7 to 2.8 mm, or 1.1% to 1.9%.

CONCLUSIONS

The construction of a catheter/sensor system with the ability to provide accurate spatial/anatomical localization data for the hepatic venous system is feasible. This assembly will eliminate the need for ancillary imaging systems for catheter/sensor delivery to an individual organ system and potentially can be positioned at the bedside in a fashion similar to the pulmonary artery flotation catheter.