Icodextrin Provides Long Dwell Peritoneal Dialysis and Maintenance of Intraperitoneal Volume

Icodextrin 7.5% is an isosmolar solution for once-daily use in peritoneal dialysis for patients with end-stage renal failure (ESRF). It produces substantial ultrafiltration (UF), performing best over longer dwells of 8–12 h in continuous ambulatory peritoneal dialysis (CAPD) patients, and up to 16 h in automated peritoneal dialysis (APD) patients. Subsequent use in other clinical areas (ultrafiltration failure) and normal postmarketing clinical experience has established its tolerability and safety profiles; a small number of patients, including those with diabetes, have now received icodextrin for up to 6 years. Icodextrin's ability to maintain intraperitoneal volume over many hours has led to its undergoing development as an intraperitoneal drug delivery system for targeted regional delivery of anticancer drugs and lymphatic delivery of anti-HIV treatment. Isosmolar icodextrin 7.5% solution represents the first major advance in the treatment of ESRF by peritoneal dialysis since the development of CAPD using glucose-based solutions 20 years ago.     

Fas Expression on Peritoneal Macrophages during Continuous Ambulatory Peritoneal Dialysis Peritonitis

Background. Peritonitis is a common complication of end stage renal failure (ESRF) patients receiving continuous ambulatory peritoneal dialysis (CAPD). Peritoneal macrophage may participate in the activation of specific T cells and in the generation of local cell-mediated immunity to various pathogens. The purpose of this study is to investigate the possible role of macrophage in CAPD patients with peritonitis. Methods. We evaluated the expression of Fas receptor (CD95), ICAM-1 (CD54), CD25, and CD69 by two-color flow cytometry on extravasted macrophages from 16 ESRF patients on CAPD with peritonitis (peritonitis-positive) and compared them to 11 ESRF patients on CAPD without peritonitis (peritonitis-negative) and normal controls. Results. We found an increased expression of CD95, CD54, and CD25 on macrophage in peritonitis-positive group compared to controls (all p < 0.001). In the peritonitis-positive group, the CD95 expression was significantly higher than that of the peritonitis-negative group (p < 0.001). The expression of CD54, CD25, and CD69, however, was not significantly different between the peritonitis-positive and peritonitis-negative CAPD subgroups. Conclusion. We found an abnormally increased percentage of macrophage-expressing Fas receptor and ICAM-1, and the percentage of CD95+ macrophage, but not those of other markers, were increased among the subset of CAPD patients with peritonitis. The later finding suggests that this macrophage phenotype is associated with peritonitis occurring in CAPD.     

The use of continuous peritoneal dialysis in Europe for the treatment of children with end-stage renal failure: data from the EDTA Registry

The demographic data on the use of continuous peritoneal dialysis in Europe for children starting renal replacement therapy under the age of 15 years was obtained from data collected by the Registry of the European Dialysis and Transplant Association--European Renal Association (EDTA Registry) on individual patient questionnaires 1980-1986. Continuous ambulatory peritoneal dialysis (CAPD) and its variants appeared to be increasingly utilised as treatment for children with end-stage renal failure (ESRF) and accounted for approximately 25% of all renal replacement therapy (RRT). Important differences in its use in various European countries are demonstrated. The proportional contribution of CAPD to treatment was higher during the first year of RRT and gradually decreased thereafter. No significant sex differences existed in the use of this treatment. Approximately 70% of all patients on CAPD were older than 6 years of age, but it is in those under 6 years that the highest proportion are put on CAPD as first method of treatment for end-stage renal failure. The most common cause of abandonment of this treatment was peritonitis, which contributed 50% of the drop-out rate.     

Clinical, radiological and serum amyloid P component scintigraphic features of beta2-microglobulin amyloidosis associated with continuous ambulatory peritoneal dialysis.

BACKGROUND: Beta2-Microglobulin (beta2M) amyloidosis occurs in patients with end-stage renal failure (ESRF) who undergo long-term continuous ambulatory peritoneal dialysis (CAPD), but its prevalence in patients treated exclusively by CAPD is unknown. In addition, its features may differ from those of haemodialysis-associated beta2M amyloidosis because CAPD is more biocompatible. METHODS: We performed serum amyloid P component (SAP) scintigraphy, a specific technique for imaging amyloid deposits, in 13 consecutive patients with ESRF who had been dialysed for >5 years, at least 80% of the time by CAPD. Clinical and radiological features of beta2M amyloidosis were sought and compared with the results of SAP scintigraphy. RESULTS: SAP scans showed articular amyloid deposits in seven patients, all of whom had evidence of carpal tunnel syndrome and four of whom had arthralgia characteristic of dialysis amyloidosis. Typical radiographic bone cysts were present in only one case who had been dialysed for >17 years. The remaining six patients had no clinical, radiological or scintigraphic evidence of beta2M amyloidosis. CONCLUSIONS: The prevalence of beta2M amyloidosis in this study was comparable with that in reported haemodialysis populations. Many of the amyloid deposits demonstrated by SAP scintigraphy were not associated with symptoms, but larger and longer term studies are required to determine whether CAPD favourably influences their clinical expression.     

Psychosocial adjustment to end-stage renal failure: comparing haemodialysis,continuous ambulatory peritoneal dialysis and transplantation

Seventy-three children and adolescents in end-stage renal failure (ESRF) undergoing haemodialysis (n=32), continuous ambulatory peritoneal dialysis (CAPD) (n=28) or with a functioning transplant (n=13), were assessed, with their parents, on adjustment to dialysis and psychological functioning. Quantitative assessment techniques were used; the three treatment groups were compared using the Mann-Whitney U test. Findings showed a number of advantages of transplantation over dialysis, and of CAPD over haemodialysis. Children with transplants suffered less functional impairment (P=0.007), less social impairment (P=0.001) and fewer practical difficulties associated with treatment (P=0.000) than children undergoing dialysis. Parents of children with transplants also reported fewer practical difficulties than parents of children on dialysis (P=0.002). Dialysis and transplant groups did not differ on children's or parents' reports of psychological stress associated with treatment, parents' reports of marital strain, children's and parents' levels of anxiety and depression or children's behavioural disturbance. Compared with children undergoing hospital haemodialysis, those using CAPD suffered less social impairment (P=0.004), reported better adjustment to dialysis (P=0.031) and fewer practical problems associated with treatment (P=0.005), had lower depression scores (P=0.054), and showed less behavioural disturbance (P=0.013). Parents of children undergoing either CAPD or hospital haemodialysis reported similar practical difficulties, psychological stress or marital strain associated with treatment, but mean depression and anxiety scores were lower in the parents of children undergoing CAPD (P=0.042 andP=0.054). The findings have clear implications for clinical practice and may help to choose the most appropriate renal replacement therapy for children in ESRF.     

Peritoneal morphology in children treated by continuous ambulatory peritoneal dialysis

Fifty peritoneal biopsies (PB) from 35 patients with end-stage renal disease, treated by continuous ambulatory peritoneal dialysis (CAPD) and aged 2 months to 18 years, were examined by light microscopy (n=50) and/or scanning electron microscopy. PB were performed during surgical procedures immediately before the start of, during, or after the cessation of CAPD treatment. PB from 15 children without renal disease undergoing laparatomy were examined similarly. Before the start of CAPD, a scarcity and shortening of the mesothelial microvilli was observed by scanning electron microscopy. During and after CAPD, variable alterations of mesothelium, interstitium and capillaries were found. The mesothelial layer was absent in all 5 PB obtained during episodes of active peritonitis. In patients treated by CAPD for longer than 6 months, mesothelial denudation was observed more frequently (6/11) than in children treated for shorter periods (1/7) (P<0.08). Fibrosis of the peritoneal membrane was present in about 50% of patients during or after the cessation of CAPD without impairment of peritoneal function. No correlation was found between the presence of fibrosis and the frequency of peritonitis or the duration of CAPD treatment.     

Renal replacement therapy for end-stage renal failure before 2 years of age.

This report concerns 296 children (67% males and 33% females) from 24 countries who started renal replacement therapy (RRT) for end-stage renal failure between 1969 and 1988. Children under 2 years of age represented 3.6%, 4.4%, and 8.9% of all children under 15 years of age who started RRT in 1978-1982, 1983-1985, and 1986-1988 respectively. During the first 2 years of life, the most frequent causes of end-stage renal failure were renal hypoplasia and dysplasia (24%), and haemolytic-uraemic syndrome (17%). During 1986-1988 the initial therapy for ESRF was continuous ambulatory peritoneal dialysis (CAPD) in 60%, haemodialysis 25%, intermittent peritoneal dialysis 8%, and 7% were transplanted without prior dialysis. Between 1978 and 1988, 139 of these children were grafted; 53 received a graft (39 cadaveric, 10 living donor, 4 donor uncertain) below, and 86 (71 cadaveric, 14 living donor, 1 donor uncertain) above 2 years of age. One-year graft survival was 54% in the 53 children grafted below 2 years of age and 65% in the 86 grafted above 2 years of age. Only two of the 24 living donor grafts were lost during the first year after grafting. These results compare favourably with the 67% 1-year graft survival of all 278 children aged 2 to less than 6 years at grafting in 1978-1988 on the Registry's file. The 3-year survival of all children aged less than 2 years at start of RRT was 65% in 1978-1982 and rose to 78% in 1986-1988. Twenty-three percent of all deaths were caused by infections.(ABSTRACT TRUNCATED AT 250 WORDS)     

Malnutrition–Inflammation–Atherosclerosis (MIA) Syndrome Components in Hemodialysis and Peritoneal Dialysis Patients

Background. Malnutrition, inflammation, and atherosclerosis (MIA syndrome) are common in end-stage renal disease (ESRD) patients. Each component of MIA syndrome is the predictor of outcomes in ESRD patients. In this cross-sectional study, we aimed to compare both dialysis modalities for MIA syndrome components. Material and Methods. Thirty hemodialysis (HD) (mean age 44 ± 11 years, 14 male and 16 female, mean time on dialysis: 31.0 ± 19.0 months) and 30 continuous ambulatory peritoneal dialysis (CAPD) patients (41 ± 9 years, 12 male and 18 female, mean time on dialysis: 25.5 ± 21.5 months) were included. In order to determine malnutrition in ESRD patients, serum albumin level and anthropometric measurements were used. For inflammation, serum C-reactive protein level, erythrocyte sedimentation rate, and fibrinogen levels were measured. Mean-carotid artery intima media thickness (m-CIMT), presence of carotid plaque and serum homocysteine level were used to determine atherosclerosis. Results. Five CAPD patients (16%) and one HD patient (3%) was hypoalbuminemic. HD and CAPD groups were similar for inflammation. Mean-CIMT and serum homocysteine level were higher in HD patients than CAPD patients. There was a positive correlation between homocysteine and m-CIMT. Conclusion. Before choosing renal replacement therapy, malnutrition, inflammation, and atherosclerosis parameters must be investigated in ESRD patients. Hemodialysis seems to be more advantageous for malnutrition components than CAPD. Both dialysis modalities seem to be similar for inflammation, and CAPD modality has superiority for atherosclerosis. Before choosing the type of renal replacement therapy, assessment of MIA syndrome components could be useful for individualization of the decision on which dialytic modality is appropriate in ESRD patients.     

Tamoxifen therapy in encapsulating sclerosing peritonitis in patients after kidney transplantation

Sclerosing encapsulating peritonitis (SEP) is a serious complication of long-term continuous ambulatory peritoneal dialysis (CAPD) associated with obstructive symptoms and sclerosis of the peritoneal membrane. We present two cases that were successfully treated with tamoxifen and corticosteroids. Case 1: A 40-year-old patient developed end-stage renal failure (ESRF) and was managed with CAPD. He was hospitalized with symptoms of small bowel obstruction. He underwent laparotomy confirming the diagnosis of SEP. The patient was given tamoxifen 20 mg twice a day. Case 2: A 55-year-old patient with ESRF secondary to membranous glomerulonephritis. After having a cadaveric renal transplant in 1978 that failed 20 years later, the patient returned to CAPD. Six years later he had an uneventful kidney transplant and the peritoneal dialysis catheter was removed. However, 8 months later he presented with symptoms of small bowel obstruction and gross blood stained ascites. He also underwent a laparotomy that confirmed the diagnosis of SEP after biopsy. The patient was started on 20 mg of tamoxifen twice a day. Both patients' symptoms were improved gradually with an increase of serum albumin and body weight. Tamoxifen may be useful in the treatment of patients diagnosed with SEP.     

Continuous peritoneal dialysis in children: a single-centre experience in a developing country

Continuous peritoneal dialysis (CPD) is the most commonly used modality of dialysis in children. Continuous ambulatory peritoneal dialysis (CAPD) has been an established form of therapy in adult patients with end-stage renal failure in India for more than a decade. There is a paucity of published experience of CPD in children from developing countries. We retrospectively studied children with end-stage renal failure (ESRD) that had been on CAPD over the past 10 years. Thirty patients with ESRD, mean age 13±8 years (range 5–21 years), male 18, were started on CAPD from 1994 to October 2004. The mean break-in period was 12±3 days. Of these 30 patients, 15 had a total of 21 episodes of peritonitis. The peritonitis rate was 0.58 episodes per patient year. E. coli was the commonest organism causing peritonitis. On outcome analysis, 7/30 (23.3%) patients received a renal transplant, while 11/30 (36.6%) continued on CAPD, awaiting a kidney transplant. Of the rest, eight (26.6%) patients died, two (6.7%) suffered technique failure and were changed to haemodialysis, and two (6.7%) were lost to follow-up after 2 months. The mean cumulative survival time of patient on CPD was 42 months. We conclude that CPD is a viable option for dialysis in ESRD children in a developing country and is a successful bridge between ESRD and renal transplantation     

Dialysis Methods May Affect Carotid Intima–Media Thickness in Chinese End-Stage Renal Disease Patients

Atherosclerosis is the most common cause of cardiovascular morbidity in end-stage renal disease (ESRD) patients and carotid intima–media thickness (IMT) is an early independent predictor of atherosclerosis. The aim of this study is to compare the continuous ambulatory peritoneal dialysis (CAPD) and the maintenance hemodialysis (MHD) for carotid IMT in Chinese ESRD patients. A total of 72 CAPD patients, 92 MHD patients, and 50 age- and sex-matched healthy controls were included. Dialysis patients were divided into five subgroups according to dialysis duration: 3–6, 7–12, 13–59, 60–119, and 120–179 months. Carotid IMT and carotid plaques were detected for each patient. The carotid IMT and total plaque detection rate in the CAPD and MHD groups were considerably higher than in the healthy control group (p < 0.01). No significant difference was found in the carotid IMT and total plaque detection rate between the CAPD group and the MHD group (p > 0.05). However, after stratification by dialysis duration, the total carotid IMT in the CAPD subgroup was higher than in the MHD subgroup in dialysis duration of 60–119 and 120–179 months (p < 0.05), and there was no significant difference in the total plaque detection rate between the CAPD and MHD subgroups in the same dialysis duration (p > 0.05). Our study showed that both CAPD and MHD affect carotid IMT in Chinese ESRD patients, and the degree of atherosclerosis in CAPD patients might be higher than that in MHD patients after 5 years of dialysis.     

Comparison of quality of life of patients on continuous ambulatory peritoneal dialysis, hemodialysis, and after transplantation

Preliminary findings regarding quality of life of 458 renal patients treated by in-center hemodialysis, continuous ambulatory peritoneal dialysis (CAPD), or transplantation indicate more favorable adjustment for CAPD patients when compared with center hemodialysis patients. Patients with a successful transplant show the highest overall adjustment when compared with both groups of dialysis patients.     

Rhodococcus equi peritonitis in continuous ambulatory peritoneal dialysis

The human Rhodococcus equi (R. equi) infection is now emerging, although extrapulmonary manifestation and isolation from patients without human immunodeficiency virus (HIV) infection remains unusual. Considerable effort is required to correctly identify and diagnose this facultative pathogen in patients with peritonitis in end-stage renal failure (ESRF) on continuous ambulatory peritoneal dialysis (CAPD). In the six cases of R. equi CAPD peritonitis reported in this series, diagnoses were made, on average, after 15 days and prolonged antibiotic therapy with morbidity in two patients. A diagnosis of R. equi should be considered in patients with suspected diphtheroid or Nocardia CAPD peritonitis, even with no history of animal contact. This study is the largest series on R. equi CAPD peritonitis and highlights the impact of this disease.     

Hyperlipidemia in pediatric patients undergoing peritoneal dialysis

We evaluated serial measurements of serum lipid levels in 68 patients aged 12.6±4.7 years undergoing treatment with continuous ambulatory peritoneal dialysis/continuous cycling peritoneal dialysis (CAPD/CCPD). Fasting mean levels of triglycerides (TG) and cholesterol (C) were elevated above the 95th percentile of published normal values by 102% and 19%, respectively, at the start of dialysis. Except for a shortterm decrease in TG levels at 6 and 9 months, no significant change in mean lipid levels was observed during a follow-up period of 2 years. At initiation of dialysis, elevated TG and C levels were present in 90% and 69% of the patients, respectively. The prevalence of hyperlipidemia (HL) varied between 63% and 88% (TG) and 61% and 93% (C), respectively, during the follow-up period. TG and C levels were not correlated with caloric intake (evaluated in 17 patients), serum albumin levels, treatment modality (CAPD or CCPD), a history of the nephrotic syndrome, or previous treatment with hemodialysis or transplantation. However, a significant inverse correlation was observed between age and serum lipids at the initiation of dialysis treatment and after 1 year (TG:r=–0.40; C:r=–0.44). Our data indicate a high prevalence of HL but no significant change of serum lipid levels during 2 years of treatment with CAPD/CCPD.     

Plasma Fatty Acid Composition in Continuous Ambulatory Peritoneal Dialysis Patients: An Increased Omega-6/Omega-3 Ratio and Deficiency of Essential Fatty Acids

Abstract

Patients with end-stage renal disease, including those treated with peritoneal dialysis, have a high risk for death, particularly from cardiovascular causes. Plasma fatty acid (FA) composition is used as an indicator of disease risk, because its alteration has been related to metabolic disease and cardiovascular disease. For this purpose, we have measured plasma FA composition in continuous ambulatory peritoneal dialysis (CAPD) patients and compared them with those of healthy subjects. This study was performed on 51 (21 M, 30 F) CAPD patients at least 6 months under dialysis, aged 20–75 years (mean 47.81 ± 11.8 years) and 45 (25 M, 20 F) healthy control subjects aged 20–60 years (mean 38.62 ± 12.9 years). Plasma 10-cis-pentadecanoic acid, 10-cis-heptadecanoic acid, heneicosanoic acid, tricosanoic acid, nervonic acid, saturated fatty acid, and monounsaturated FA levels and delta 9 desaturase activity were significantly higher whereas linoleic acid, linolenic acid, 11,14-eicosedienoic acid, arachidonic acid, docosahexaenoic acid, and omega-3 FA levels were significantly lower in the CAPD group than those in the healthy group. Our results show that there are FA abnormalities and especially a depletion in essential FA levels and a high level of omega-6/omega-3 ratio in CAPD patients, the underlying mechanism of which is not known and needs to be investigated. Therefore, we believe that essential FA supplementation should be encouraged for CAPD patients.     

Streptococcus gordonii Peritonitis in a Patient on CAPD

We report the first case of Streptococcus gordonii-related continuous ambulatory peritoneal dialysis (CAPD) peritonitis. He is a 69-year-old man with end-stage renal failure due to chron ic glomerulonephritis who had been put on CAPD for 1 year. He was successfully treated with a 2-week course of cefazolin. This case highlights the emerging threat that S. gordonii can be the source of infection in patients on CAPD.     

Morbidity and mortality of continuous ambulatory peritoneal dialysis: regional experience and long-term prospects

The Network Coordinating Council (NCC) #4 continuous ambulatory peritoneal dialysis (CAPD) study was designed to gather basic demographic information and analyze selected outcome parameters on all patients started on CAPD in Southern California/Southern Nevada. Between early 1979 and Dec 31, 1983, 775 patients were enrolled in the study for a total experience of 878.5 patient-years. Demographic data revealed 25% of patients were over 60 years old and 17.4% were less than 20 years old at the start of CAPD, 65% were white, and 28% had chronic glomerulonephritis as a cause of end-stage renal disease (ESRD). Compared to all NCC #4 patients on dialysis (hemo and peritoneal), the young (less than 20 years old) and whites were overrepresented on CAPD. Patient outcome was assessed by life table analysis which revealed 90%, 80%, 70%, and 70% patient survival at 12, 24, 36, and 43 months, respectively; and technique success of 80%, 60%, 48%, and 40% for the same time periods, respectively. Over half of the dropout from CAPD and one third of the hospitalizations were related to recurrent infection. Few patients transferred from CAPD because of dissatisfaction with the technique or because of peritoneal membrane failure. CAPD is an excellent form of therapy for ESRD that controls uremia adequately and improves the quality of life for many patients. Long-term application of CAPD is hampered, however, by the high frequency of recurrent infections.     

Platelet Activity and Serum Homocysteine Levels in Patients with End-Stage Renal Failure with Regard to Dialysis Modality

Background. Recent evidence suggests that the activation of platelets and their interaction with circulating cells are important independent risk factors for atherosclerosis. In non-uremic patients with symptomatic peripheral vascular disease, a relationship between serum homocysteine (Hcy) levels and platelet activity had been reported. The purposes of this study were to evaluate of effects of dialysis modality on platelet activity in patients with end-stage renal failure and to investigate the relationship between platelet activity, Hcy, and left ventricular hypertrophy (LVH). Material and Methods. In age and sex matched 19 healthy subjects, 20 hemodialysis (HD) patients, and 18 continuous ambulatory peritoneal dialysis (CAPD) patients, the expression of platelet surface receptors CD41, CD61, CD42a, and CD62P were investigated. CD62P expression was statistically significantly increased in HD patients compared with CAPD patients and controls (34.4 ± 22.5%; 17.3 ± 19.6%, 12.0 ± 15.6%, respectively, p < 0.05), but not in CAPD patients compared with controls. There was a positive correlation between CD62 expression and duration of dialysis in HD patients (r = 0.498, p = 0.026). Mean plasma Hcy levels in dialysis patients were higher than reference levels. However, we could not find any relationship between CD62 expression, Hcy, and LVH in both groups (p > 0.05). Conclusions. Hemodialysis and peritoneal dialysis (PD) have a different impact on the expression of CD62: peritoneal dialysis seems to have a more favorable effect. It may be possible that the differences in biocompatibility between PD and HD potentially contribute to differences in CD62 expression.     

The role of continuous ambulatory peritoneal dialysis in end-stage renal failure due to multiple myeloma

A study in 10 patients (eight male, two female; mean age 61.9 +/- 10.7 years) suffering from multiple myeloma (MM) and end-stage renal failure (ESRF) is detailed. Continuous ambulatory peritoneal dialysis (CAPD) was the preferred mode of chronic dialysis in all the patients. Survival after diagnosis was 32.2 +/- 23.9 months. Survival after starting dialysis was 24.6 +/- 20.6 months. All patients on CAPD were adequately dialyzed and in good fluid control. Peritonitis was the main problem on CAPD (one episode per 5.6 patient-months). The majority of peritonitis episodes responded to intraperitoneal antibiotic therapy. One patient with Staphylococcus aureus peritonitis, septicemia, and neutropenia secondary to chemotherapy, died. Recommendations for prophylaxis and treatment of peritonitis are given. Three patients were transferred to hemodialysis. The use of subclavian vein catheters during hemodialysis was associated with a high incidence of gram-positive septicemia. Alkylating agent-based chemotherapy resulted in hematological responses in five patients. Survival after diagnosis in those responders was 47.4 +/- 25.6 months, compared with 17.0 +/- 7.2 months in the nonresponders (P less than 0.05). All responders subsequently relapsed. Four patients died with progressive myeloma. Bone marrow suppression resulted in a high blood transfusion requirement, neutropenia, and thrombocytopenia associated with bleeding into the gastrointestinal tract and central nervous system. Uremic myeloma patients can be adequately dialyzed using CAPD. Those patients who do not have an initial hematological response have a poor prognosis.     

Orthostatic hypoxaemia in dialysed adult polycystic kidney disease patients

BACKGROUND: Recently we observed a unique clinical phenomenon, namely, orthostatic or postural hypoxaemia in a 72-year-old female adult polycystic kidney disease (APKD) patient, maintained on CAPD. Extensive investigations failed to yield a satisfactory explanation for her ambulatory hypoxaemia. METHODS: To validate our observation, 15 dialysed patients underwent blood gases analyses in both the supine and ambulatory positions (SpO2 and ApO2 respectively). Patients were divided into two groups: group 1 (n-7) whose end-stage renal failure (ESRF) was due to APKD and group 2 (n-8) in whom ESRF was due to other causes. Both haemodialysed (HD) and CAPD patients were included. ApO2 was determined as the pO2 immediately upon standing up. Readings in HD patients were taken at the end of the dialysis session, that is, at the patients' dry weight. RESULTS: Respective SpO2 and ApO2 of the two groups were 85 +/- 17.1 and 78 +/- 20.5 vs 85.8 +/- 19 and 91 +/- 21 mmHg. Delta change in pO2 defined as the mean decrease (negative value) or mean increase (positive value) of ApO2 in relation to SpO2 was -7.85 (group 1) vs + 5.2 mmHg (group 2), P < 0.005. In group 1, six of seven patients demonstrated a negative delta. In group 2, four of eight showed a positive delta whilst the remaining four had no change in the delta value. CONCLUSION: Orthostatic hypoxaemia may occur in dialysed patients whose ESRF is due to APKD.