Clinical and metabolic aspects of continuous ambulatory peritoneal dialysis (CAPD)

Experience with CAPD in 14 patients, treated for periods of 2–10 months, is presented. Clinical and biochemical control of uremia appeared adequate in all patients except one. Control of extracellular volume and hypertension was easier with CAPD than with intermittent peritoneal dialysis (IPD). Nine episodes of peritonitis occurred in 5 patients (one peritonitis/8 patients months). Mean protein loss was 9.7 ± 2.7 g per day. In 6 patients on IPD oral glucose tolerance test resulted in a paradoxical rise of HGH, whereas this was not observed after 4 months of CAPD.

Multiple dose kinetics of ofloxacin and ofloxacin metabolites in haemodialysis patients

7 patients with end-stage renal disease on regular haemodialysis were treated orally with a loading dose of 200 mg ofloxacin and multiple maintenance doses of 100 mg per 24 h for 10 days. The pharmacokinetics of ofloxacin and its metabolites were studied at the end of the treatment period. Plasma and dialysate concentrations of ofloxacin and ofloxacin metabolites were measured by HPLC. Peak (3.1 mg.l-1) and trough levels (1.6 mg.l-1) and the AUC of ofloxacin were comparable to the values in healthy volunteers given 300 to 400 mg ofloxacin p.o. The mean half-life, determined in the dialysis-free interval (t1/2 beta) and during the haemodialysis session (t1/2 HD), was 38.5 h and 9.9 h, respectively. Extrarenal clearance (32.7 ml.min-1) was unchanged as compared to that reported in healthy volunteers after a single dose of ofloxacin. The fractional removal by haemodialysis amounted to 21.5%. Two metabolites, ofloxacin-N-oxide and demethyl-ofloxacin, were detected in plasma. Despite prolonged t1/2 beta of both metabolites (66.1 and 50.9 h) and multiple doses of ofloxacin the peak concentrations of the metabolites reached only 14% and 5% of that of the parent drug, respectively. It is concluded that in patients on regular haemodialysis treatment the dosage adjustment employed resulted in safe and therapeutically favourable plasma concentrations. The observed accumulation of ofloxacin metabolites does not appear to have any toxic or therapeutic significance.

A new method to evaluate the CAPD-catheter-exit and other percutaneous devices

A method that has proved to be the most sensitive approach for the early diagnosis of infection of the oral mucosa around dental implants has been used to monitor the exit-sites of percutaneous devices. For three months the state of the skin-catheter interface of 13 CAPD-patients was examined every four weeks. This examination included the measurement of pocket depth with the aid of a periodontal probe, the measurement of SFFR (sulcus-fluid-flow-rate) using standardized filter paper strips and a bacteriological swab of the exit-site. The results obtained demonstrated that SFFR can be measured around percutaneous implants. The measurement of SFFR appeared to be more useful in the monitoring of exit-sites of percutaneous devices than the measurement of pocket depth or the use of bacteriological swabs. Further studies for prolonged periods are necessary to determine whether measurement of SFFR can reliably predict onset of exit-site infection before clinical signs become evident.

Pharmacokinetics of ofloxacin and adequacy of maintenance dose for patients on haemodialysis

Seven patients, three females and four males, aged 33-70 years, with end-stage renal disease, on regular haemodialysis were treated for various infections with a loading dose of 200 mg and multiple maintenance doses of 100 mg ofloxacin per 24 h over ten days orally. The pharmacokinetics of ofloxacin were studied at the end of the treatment period before, during and after a haemodialysis session. Concentrations in plasma and dialysate were measured by HPLC. Mean trough concentration (+/- S.D.) of ofloxacin before the last drug intake was 1.6 (+/- 0.6) mg/l. At a Tmax of 1.5 (+/- 1.1) h a peak concentration of 3.1 (+/- 1.0) mg/l was reached. The mean half-lives of ofloxacin (+/- S.D.) which were determined in the dialysis-free interval (T1/2 beta) and during the haemodialysis session (T1/2HD) were 38.5 (+/- 14.1) h and 9.9 (+/- 3.4) h, respectively. Mean dialyser clearance (+/- S.D.) was 59.2 (+/- 15.4) ml/min and the fractional removal of ofloxacin amounted to 21.5 (+/- 8.2)%. The data show that in patients with regular haemodialysis treatment a loading dose of 200 mg orally and daily administration of 100 mg orally of ofloxacin results in therapeutically favourable and well tolerated plasma concentrations when given at the end of haemodialysis.

Task-related variation in airborne concentrations of laboratory animal allergens: studies with Rat n I

To define airborne allergen exposure during various tasks with rats in a laboratory, concentrations of allergen Rat n I were measured by radioimmunoassay in extracts from filters in personal air sampling devices that were worn by laboratory workers while they were performing these tasks. The tasks included feeding, cage cleaning, handling, injection, surgery, and sacrifice. Median concentrations encountered during feeding or cleaning (21 ng/m3) and injection or handling (13 ng/m3) were higher than those associated with surgery or sacrifice (3.1 ng/m3; p less than 0.01). Area samples in animal-holding rooms contained 3.4 ng/m3 during animal handling and 2.3 ng/m3 at other times. Very low concentrations were found in air outside the handling room, in unused laboratories, or outside air. We concluded that certain tasks incur a higher risk of allergen exposure but that exposure may occur anywhere within an animal laboratory environment.

Advantages of bicarbonate hemodialysis

Six patients with frequent episodes of symptomatic hypotension during acetate dialysis were treated with bicarbonate dialysis. In all patients blood pressure, heart rate, and arterial acid-base values were measured every 30 minutes during each of the five treatments with acetate dialysis and bicarbonate dialysis. Hemodynamic parameters were measured invasively in all patients during bicarbonate dialysis and in three of them also during acetate dialysis. Additionally, continuous long-time monitoring with electroencephalography was performed during acetate dialysis and bicarbonate dialysis. During acetate dialysis the patients showed a frequent onset of sudden hypotension and arrhythmia with concomitant symptoms of the so-called disequilibrium syndrome, whereas these symptoms were nonexistent in the same patients during bicarbonate dialysis.

Clinical and metabolic aspects of continuous ambulatory peritoneal dialysis (CAPD)

Experience with CAPD in 14 patients, treated for periods of 2-10 months, is presented. Clinical and biochemical control of uremia appeared adequate in all patients except one. Control of extracellular volume and hypertension was easier with CAPD than with intermittent peritoneal dialysis (IPD). Nine episodes of peritonitis occurred in 5 patients (one peritonitis/8 patients months). Mean protein loss was 9.7 +/- 2.7 g per day. In 6 patients on IPD oral glucose tolerance test resulted in a paradoxical rise of HGH, whereas this was not observed after 4 months of CAPD.

[Continous ambulatory peritoneal dialysis (CAPD)]

Eleven patients were treated with continuous ambulatory peritoneal dialysis (CAPD) for periods of 2-7 months (48 patient-months). Clinical and biochemical control of uremia was adequate in all patients. Control of hypertension and serum phosphate level was easier than with previous intermittent peritoneal dialysis (IPD). Mean protein loss during CAPD was 9.7 +/- 2.7 g/day. Seven episodes of peritonitis occurred in 3 patients (1 peritonitis/6.8 months). General use of CAPD cannot be recommended until the high incidence of peritonitis is reduced by urgently needed technical improvements. A potential complication of CAPD was that triglycerides were markedly elevated in 4 patients.