In an attempt to clarify the pathogenesis of the disturbed calcium metabolism which sometimes follows partial gastrectomy, we determined plasma 25-hydroxyvitamin D (25-OH-D) concentrations and urinary cyclic 3',5'-adenosine monophosphate (cAMP) excretion in patients who had previously undergone Billroth II gastrectomy and who were without clinical evidence of bone disease. In 17 Billroth II patients plasma 25-OH-D concentrations were reduced (12.6 +/- 4.6 ng/ml, mean +/- SD) compared to values in 17 control patients with diseases not affecting calcium metabolism (31.6 +/- 12.9 ng/ml, P less than 0.001). Urinary cAMP excretion, in part reflecting parathyroid function, was higher in 17 Billroth II patients (5.0 +/- 2.5 micronmol/day) than in the control patients (2.6 +/- 1.3 micronmol/day, P less than 0.001). These results suggest impaired nutrition of vitamin D and secondary hyperparathyroidism in Billroth II patients. While the cause of this phenomenon is unclear, it may contribute to the disturbance of calcium metabolism in patients who have had subtotal gastrectomy.

In 12 patients undergoing coloscopy, 0.5 mg digoxin in aqueous alcoholic solution was injected into the transverse colon. The late maximum of the blood level curve at about 2 hours after the administration suggested delayed absorption of the glycoside. However, the 24 hour urinary excretion of 17 +/- 3.4% in 8 patients with normal colonic mucosa demonstrated extensive absorption in the distal part of the bowel. The results have been contrasted with the findings in 4 patients with ulcerative colitis who excreted only 1.66 +/- 0.6% of the given dose in 24 hours.

Biological availability of digoxin tablets was measured during maintenance therapy in ten hospitalized patients who had had a Billroth II gastric resection at least two years previously. Twelve patients on digoxin maintenance for heart failure but without gastro-intestinal disease served as controls. The mean value of daily digoxin urinary excretion over ten days in the resection group was 38.09 +/- 0.70% of the administered dose. The serum-digitalis level 12 and 24 hours after the last dose of glycoside (0.5 mg) was 1.30 +/- 0.04 ng/ml and did not significantly differ from that of the control group, nor did digoxin elimination in urine and the digoxin/creatinin excretion ratio. It is concluded that two-third gastric resection with exclusion of antigrade duodenal passage does not influence biological availability of digoxin given in tablets.