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D L Earnest

Publications and source records attributed to D L Earnest.

At least 73 records · Page 4Linked to original sources
PubMed1981

Medical evaluation of the patient with liver disease prior to surgery.

Patients with liver disease have increased morbidity and mortality following general anesthesia and surgery when compared with the general population. The increase in mortality appears to be directly related to the severity of hepatic parenchymal cell failure and to the magnitude and duration of the surgical procedure. The importance of preoperative detection of subclinical liver disease by use of a variety of blood tests has been emphasized. However, with the exception of hepatitis B and non-A non-B hepatitis, a precise diagnosis of the exact cause of liver disease is usually less important to the anesthesiologist than is a full characterization of the severity of hepatic dysfunction. Recognition and understanding of the central metabolic role played by the liver in maintaining carbohydrate, fat, and protein homeostasis can help in predicting and managing abnormalities which may complicate the preoperative, interoperative, and postoperative periods. Liver failure after anesthesia and surgery is treated by the same management principles used for liver failure with acute hepatitis. The incidence of postoperative renal failure may be increased in patients who have severe hyperbilirubinemia and its occurrence should be differentiated from the hepatorenal syndrome. It should be understood that complications of portal hypertension may develop in the absence of overt hepatic parenchymal cell failure and that liver failure may occur without gross evidence of portal hypertension. Either situation must be recognized and treated as far in advance of surgery as possible. In general, elective surgery in the patient with liver disease should be delayed until consequences of hepatic parenchymal cell dysfunction and portal hypertension are optimally corrected.

Bile↗
PubMed1980

Oxalate transport across the isolated rat colon. A re-examination.

A net absorption of oxalate and chloride was observed when isolated, short-circuited segments of rat colon were bathed by a calcium-containing buffer. Removal of calcium promoted a two-fold decrease in transmural resistance, while the net chloride flux was reduced and the net oxalate transport abolished. It was concluded that net oxalate absorption was not observed in previous studies (employing calcium-free buffers) because calcium is reqiured to maintain the integrity of the conductive pathways across colonic epithelia.

Animals↗
PubMed1980

Factor II antigen in liver disease and warfarin-induced vitamin K deficiency: correlation with coagulant activity using Echis venom.

Four coagulation factors (II, VII, IX, X) are synthesized in the liver as precursor forms. Vitamin K is necessary for their conversion to functional factors. Factor II precursor is antigenically similar to factor II and can be activated to form thrombin by Echis carinatus venom. Forty-one patients with liver disease and 30 patients with vitamin K deficiency (Warfarin treated), were compared with 51 normal patients. Rats with CCl4-induced hepatic necrosis and animals given Warfarin were also studied. The following measurements were made: standard prothrombin time; Echis clotting time; factor II coagulant assay with thromboplastin; factor II assay with Echis venom; and factor II antigen (human) by electroimmunoassay. In animals and humans with liver disease, factor II was reduced, as measured by all techniques. With vitamin K deficiency functional factor II was reduced, but factor II antigen and Echis factor II activity were normal. THe data suggest that the prothrombin time and Echis coagulation methods can be used to differentiate whether the coagulopathy in liver disease is due to reduced precursor levels of factor II, vitamin K deficiency (ie, impaired formation of functional from precursor factor II), or both.

Animals↗
PubMed1980

Idiopathic cecal ulcer. Diagnosis by colonoscopy followed by nonoperative management.

Idiopathic ulcer of the cecum has been considered a rare condition requiring surgical treatment because of a high incidence of complications, including bowel perforation. Cecal ulcerations are usually diagnosed at the time of surgery for presumed appendicitis or peritonitis of unknown origin. Preoperative diagnosis of cecal ulcer by barium enema has been unreliable and previous literature cites only one case diagnosed by colonoscopy. We describe four cases in which the diagnosis was made at colonoscopy. Three of our four patients were treated conservatively and did not require laparotomy. Idiopathic cecal ulcer should be considered in the differential diagnosis of lower gastrointestinal hemorrhage as well as atypical appendicitis. If the diagnosis of cecal ulcer is made by colonoscopy in a patient without evidence of an acute abdomen, conservative management may be followed by complete healing, avoiding unnecessary surgery.

Adult↗
PubMed1978

Sex differences in hepatic sulfation of taurolithocholate in the rat.

Metabolism of the bile salts by formation of sulfate esters is catalyzed by bile salt sulfotransferase, an enzyme isolated from rat liver and kidney. The activity of bile salt sulfotransferase was measured in liver and kidney of male and female rats and in oophorectomized rats with or without estrogen replacement. In vitro sulfotransferase activity was correlated with in vivo sulfation by measuring the percentage of an infused dose (0.03 micron per 100 g per min) of taurolithocholate, which was excreted in bile as the sulfate. The activity of sulfotransferase in liver was higher in females (26.3 +/- 3.0 pmoles per mg of protein per min) than in males (9.6 +/- 3.9) and was lower (12.1 +/- 3.8) after oophorectomy. The decrease in activity was prevented by replacement of estrogen. Renal sulfotransferase activity did not differ between the sexes and was unaffected by oophorectomy. Hepatic sulfotransferase activity measured in vitro correlated with in vivo sulfation of taurolithocholate. This study shows definite sex differences in hepatic bile salt sulfotransferase activity, which in females is affected by the presence of estrogen. The correlation between in vitro sulfotransferase activity and in vivo bile salt sulfation suggests that bile salt sulfotransferase is responsible for bile salt sulfation in vivo.

Animals↗
PubMed1977

Hyperoxaluria correlates with fat malabsorption in patients with sprue.

The effect of fat malabsorption on the absorption and renal excretion of dietary oxalate was studied in four patients with sprue and in two patients with dermatitis herpetiformis and sprue-like jejunal histology. Hyperoxaluria was present in all patients with sprue when fat malabsorption was severe. Urinary oxalate excretion decreased in two of the three patients with coeliac sprue when their fat malabsorption had improved after three months of dietary gluten restriction. Neither patient with dermatitis herpetiformis and sprue had steatorrhoea. In these patients, urinary oxalate excretion was always within normal limits. A significant positive linear relationship (y=28.25 +4-84x; r=0-82; P less than 0-01) was demonstrated between faecal fat and urinary oxalate excretion. The results of this study support the concept that severe malabsorption of dietary fat plays a primary causative role in enteric hyperoxaluria.

Calcium↗
PubMed1975

Sulfation and renal excretion of bile salts in patients with cirrhosis of the liver.

Renal excretion of bile salts was studied in 17 patients with cirrhosis of the liver. The average quantity of bile salts in urine was 10.2 plus or minus 8.3 mg per 24 hr, 56% of which were sulfated. Of the individual urinary bile salts, 24% oithocholate were sulfated. In contrast, neither sulfated nor nonsulfated bile salts could be detected in urine from 2 normal subjects. Kinetics of bile salt metabolism was measured in 2 of the cirrhotic patients after oral administration of [14C] cholate and [3H] chenodeoxycholate. Approximately 3 to 12% of bile salts synthesized in liver were excreted in urine. Most urinary bile salts (76 to 80%) were sulfated, whereas only 4 to 5% of serum bile salts and 7 to 10% of biliary bile salts were sulfated. Renal clearance of cholate was more than 3 times greater than the clearance of chenodeosycholate or deoxycholate. Renal clearance of sulfated bile salts was 20 to 200 times greaterthan the clearance of the corresponding nonsulfated bile salts.

Adult↗