Platelet counts in blood taken from femoral artery, femoral vein, cubital vein, and arteriovenous fistula.

In 20 patients under regular dialysis with an arteriovenous fistula in one forearm, platelet counts were measured in blood taken simultaneously from the cubital vein, the arterialized vein near the site of anastomosis, the femoral vein, and the femoral artery. Samples of blood from the fistula and from the cubital vein of the opposite limb were taken with and without stasis. The highest values were found in blood taken from the cubital vein without stasis. Platelet counts were identical in femoral artery and vein, but were 4.8 and 4.9%, respectively, lower than the cubital vein values. Platelet counts from fistula blood taken without stasis were 13.7% lower than in the cubital vein. Platelet counts were lower when samples of blood were taken with stasis: 11.2% in the cubital vein, 7.4% in fistula blood. The awareness of these differences is of practical importance for platelet behavior studies.

Kinetics of continuous ambulatory peritoneal dialysis (CAPD) with four exchanges per day.

Fourteen patients who had no signs of peritonitis were studied during CAPD. Different exchange time schedules were used alternating exchanges with 1.5% and 2.6% glucose solutions. Usually longer exchanges followed shorter ones and vice versa. Total exchange time varied from 2--10 hours. Maximal ultrafiltration volumes were observed after 3 hours with 1.5% and 5 hours wit 2.6% glucose solutions. For small molecular weight solutes (urea, creatinine, sodium, potassium, and phosphate) dialyzate to plasma concentration ratios tended to be lower with 2.6% glucose solutions during the shorter exchanges. Equilibrium between plasma and dialyzate was attained for all these solutes by 10 hours total exchange time. The concentration ratios for inulin were similar with both types of solution, and did not achieve equilibrium by 10 hours. Protein concentrations and losses were higher with 2.6% glucose solution. Total protein and immunoglobulin losses per 24 hours were markedly lower than those reported for intermittent peritoneal dialysis. White blood cell counts increased slightly up to 5 hours and then remained constant up to 10 hours. Mononuclear cell counts were consistently higher than those of granulocytes. The efficiency of dialysis was not markedly influenced by uneven distribution of total exchange time. If 1.5% and 2.6% glucose solutions were used for particular time schedules, slightly higher dialysis efficiency could be obtained by using hyperosmolar solutions for the longer exchanges. Ultrafiltration volumes, protein and immunoglobulin losses, cell counts in dialyzate, and clearance of inulin varied among individual patients. Protein losses correlated positively with serum protein concentration and the body surface area of the patient. Clearances of insulin also correlated with body surface area but ultrafiltration volumes did not.