Validity of iodoantipyrine clearance for measuring gastrointestinal tissue blood flow.

Simultaneous determinations of 1) the clearance (mF) of 4-iodoantipyrine (IAP) and tritiated water, 2) the mF of IAP and total circulating tissue blood volume, 3) the mF of IAP and either 15- or 25-micrometers-diam-microsphere-measured flow, and 4) 15- and 25-micrometers-diam-microsphere-measured flow were made on tissues from dog gastrointestinal tracts. Results show the mF of IAP equals or exceeds that of tritiated water in all tissue layers, and tissue blood volume does not affect the measurement of the IAP mF. Perfusion of the gastrointestinal wall exhibits macroscopic heterogeneity due to differences in perfusion of the three tissue layers, but an effect of microscopic heterogeneity on tissue mF assessment was not apparent. Composite total-wall IAP mF was not significantly different from 25-micrometers-microsphere total-wall flow and was identical to this flow when colonic locations were omitted. Comparisons of 15-micrometers-microsphere flow to IAP mF and to 25-micrometers-microsphere flow both indicated shunting of 15-micrometers-microspheres. Such shunting occurred predominantly through submucosal and muscle layers. It is concluded that IAP clearance accurately measures blood flow in gastrointestinal tissue.

Fibropolycystic disease of the hepatobiliary system and kidneys.

This complicated case of fibropolycystic disease of the hepatobiliary system and kidneys was ably and incisively analyzed by Professor Sheila Sherlock. Her clinical acumen was revealed by her ability to differentiate congenital hepatic fibrosis, Caroli's disease, and adult polycystic disease of the liver and kidney. Interesting histologic features of this case included hepatic fibrosis with intact limiting plates anc central veins and the presence of bile plugs in the ducts, but the absence of bile statsis in the parenchyma. A percutaneous transhepatic cholangiogram demonstrated the dilated intrahepatic and extrahepatic ducts. Washing out the "gunk" from the biliary tract by T-tube drainage has great limitations in this type of case. Therefore, Dr. Adson suggested irrigation of the biliary ductal system using tubed placed transhepatically, plus a wide choledojejunostomy. Dr. Sherlock questioned this surgical approach. The use of chenodeoxycholic acid for this "gunk" was suggested. In spite of the dilated ducts and pathologic changes in the liver, the patient was not jandiced and did not have stones in her biliary tract. The genetics of this patient's problems was discussed.

Multidisciplinary Conferences in Gastroenterology. Cardiovascular effects of severe liver disease.

This is the definitive review of the cardiovascular effects of liver disease. Physiologic and pathologic studies accomplished primarily in the 1950s and 1960s have been applied to a case of a 16-year-old boy with cirrhosis of the liver who presented with weakness, dyspnea, cyanosis, and clubbing. The probable mechanisms for his signs and symptoms are discussed in detail. The cause for the hyperkinetic circulation is unknown. By exclusion, the cyanosis is attributed to intrapulmonary shunting. Portapulmonary shunts are not quantitatively important. The suitability of the terms micronodular and macronodular cirrhosis is highlighted. Indications for various types of surgical portal shunts are discussed. The value of preoperative hemodynamic measurements of the portal circulation to the individual patient is debated. A liver transplant is considered in this case with no promising medical therapy and a very poor prognosis. The renal disease manifested by red cell casts in the urine is thought to be caused by an immunologic reaction in the kidney somehow related to his liver disease. This discussion is led by Dr. Jack Myers, but his opinions are correlated with those of a pathologist, radiologist, surgeon, and gastroenterologist. It is a clinical tour de force, although not all the predictions are confirmed by laboratory studies such as this patient's hepatic wedge pressure, pulmonary artery pressure, and cardiac fluoroscopy.