A Comparative Study of Blood Pressure Control with Short In-Center versus Long Home Hemodialysis.

We conducted a randomized crossover trial to establish, within patients, whether long-slow hemodialysis (HD) was associated with better blood pressure (BP) control than standard HD. Nine home HD patients, not on antihypertensive drugs, were dialyzed to the same eKt/V(urea) and target weights for 6-8 h (LD) at home and for 3.5-4.5 h (SD) in the dialysis center 3 times weekly in randomized sequence, with each phase lasting 8 weeks. Ambulatory BP, bioimpedance, neurohormones and autonomic function were measured in each phase. Pre- and postdialysis systolic, ambulatory systolic and diastolic BP were all higher with SD than with LD and intradialysis hypotension was more common. Weight, ECF volume and neurohormones did not differ between treatments. Muscle sympathetic activity was increased in both phases and cardiac sympathetic activity tended higher during SD. These findings suggest that additional factors to ECF volume may contribute to the superior BP control produced by long-slow HD.

Thirty years of universal home dialysis in Christchurch.

AIM: To review 30 years of universal home dialysis in a single dialysis unit. METHOD: Analysis for patients using home dialysis since 1969 of information from hospital visits, clinical case notes and demographic and survival data from the Australia and New Zealand Dialysis and Transplant Registry. RESULTS: Since 1969 treatment options at the Christchurch Nephrology Unit for patients with end-stage renal disease have been home haemodialysis (HD), renal transplantation and, since 1979, continuous ambulatory peritoneal dialysis (CAPD). No long-term, hospital-based treatment has been offered. During this time 493 patients, aged 3-82 years, began treatment. The mean training time for home HD was 79 days (range 23-268) and for home CAPD 7 days (range 1-35). The mean HD treatment time was 7 hours x 3 per week (range 10-36 hours/week). Between 1980 and 1995, less than 5% of patients took antihypertensive drugs and 73% of those aged 18-65 years were in full or part-time employment. The mean age of patients commencing treatment increased from 41.8 years in the 1970s to 50.1 years in the 1990s. The median patient survival from 1970-1997 was 7.75 years on home HD and 2.1 years on home CAPD. Median survival on dialysis fell in the 1990's as more diabetics and older patients with comorbidity started treatment. CONCLUSIONS: Home HD allows good rehabilitation, long treatment times and good blood pressure control which may all contribute to the superior survival of home versus hospital HD. CAPD survival in Christchurch was worse than HD, but this is probably due to patient selection. A policy of universal home dialysis is still workable provided there are sufficient resources for training and support of patients in the community.

Ambulatory blood pressure monitoring in patients receiving long, slow home haemodialysis.

BACKGROUND: Good blood pressure (BP) control has been reported previously in haemodialysis (HD) patients receiving 8-h dialysis sessions. Home HD allows patients to dialyze for long periods, but there are few data on the BP control achieved by these patients. We studied BP control, using ambulatory blood pressure monitoring (ABPM), in our home-HD patients who were receiving long-hours dialysis. METHODS: Twenty-four patients aged 52.7+/-11 years underwent ABPM. They had been on home HD for 52.9+/-39 months and dialysed for 7.2+/-1.1 h thrice weekly. Two patients were taking antihypertensive drugs. Historical data on BP and weight gains were obtained from the patients' own records. Left ventricular (LV) mass was assessed by echocardiography and total body water (TBW) by bioelectrical impedance. RESULTS: The mean 24-h BP was 129+/-17 mmHg (systolic) and 83+/-14 mmHg (diastolic). The daytime BP was 131+/-17 mmHg (systolic) and 84+/-14 mmHg (diastolic), while the night-time BP was 126+/-22 mmHg (systolic) and 81+/-17 mmHg (diastolic). Six patients (25%) had a normal circadian BP rhythm, but the rest showed a subnormal fall or an increase in BP at night. Mean 24-h BP did not correlate significantly with time on dialysis, dialysis session length, Kt/V, haemoglobin, interdialytic weight gain, or TBW. Twenty-one patients (87%) had LV hypertrophy and 16 of these had diastolic dysfunction. LV mass index was inversely correlated with nocturnal BP fall (r=-0.54, P=0.03). Non-dippers had been treated longer than dippers (29 vs 59.2 months, P=0.03) but they were similar in respect to age, dialysis session length or Hb concentration. CONCLUSIONS: Long, slow haemodialysis at home provides satisfactory daytime BP control in the majority of patients without the need for antihypertensive drugs but abnormal circadian BP rhythm and LV hypertrophy remain common.

Audit of the outcome of patients with renal failure presenting to a regional nephrology service.

AIM: To assess the outcome of patients with renal failure presenting to a regional nephrology unit. METHODS: The records of patients with plasma creatinine concentration > or = 0.30 mmol/L who presented between 1 January 1988 and 31 December 1993, or were already under follow up, were studied. RESULTS: The outcome of 491 patients (293 males) aged from 4.8 to 88.8 years, 123 of whom had acute renal failure, was assessed at 30 June 1994. Thirty seven (30%) of the patients with acute renal failure had died. Of the 372 patients with chronic renal failure 139 had started regular dialysis treatment and 95 were dead, including 27 patients, with a mean age of 71 years, who died of untreated end-stage renal failure (ESRF). For 11 (40%) of these patients the patient and/or family made the decision not to start dialysis treatment. The rates of treatment of ESRF are lower in Canterbury and Westland than those in the Auckland region. The latter can be explained partly by the differences in the demography of the respective populations. CONCLUSION: Death from untreated ESRF is uncommon in Canterbury and Westland. The rates of treatment of ESRF with regular dialysis are lower than in the Auckland region.

Effect of hemodialysis and recombinant human erythropoietin on determinants of blood viscosity.

Blood viscosity (hemorheology) is a major determinant of the rate of blood flow, and increases in viscosity are known to be involved in the etiology of vascular diseases. This placebo-controlled study investigated the independent and combined effects of hemodialysis and recombinant human erythropoietin (rHuEpo) on determinants of blood viscosity in patients with chronic renal failure and related any changes to the normal physiological range. Hemodialysis patients were shown to have a high incidence of rheological abnormalities although the degree of anemia associated with chronic renal failure compensated for these changes. The main effect of both hemodialysis and rHuEPO treatment was an increase in hematocrit associated with a rise in blood viscosity and inconsistent changes in red blood cell (RBC) deformability. The rise in viscosity was significant only following rHuEPO treatment. Hemodialysis-induced increases in blood and plasma viscosity correlated strongly with the degree of hemoconcentration. Although hemodialysis patients have inherent hemorheological abnormalities, correction of renal anemia with rHuEPO to a hematocrit level of < 0.35 in conjunction with dialysis-induced hemoconcentration did not result in adversely high blood viscosity levels in any patient.

Hemorheology and fistula function in home hemodialysis patients following erythropoietin treatment: a prospective placebo-controlled study.

The beneficial effect of correcting anemia in end stage renal failure using recombinant human erythropoietin (rHuEPO) is sometimes complicated by thrombosis of the arteriovenous fistula. This placebo-controlled study investigated the relationship between hemorheological changes caused by rHuEPO and alterations in fistula function and heparin requirements in home hemodialysis patients. Erythropoietin induced a rise in high shear rate blood viscosity, a determinant of blood flow in large vessels. Doppler assessment of brachial artery blood flows, tests of fistula function and heparin requirements were similar in the two patient groups. These findings indicate that rHuEPO treatment of renal anemia resulted in the expected rise in red blood cell mass and blood viscosity although these changes did not cause problems with arteriovenous access or alter fistula function in the short term.

Treatment of theophylline poisoning with haemoperfusion.

Two patients who had taken overdoses of theophylline were treated initially with oral activated charcoal. Owing to continued toxic plasma levels of theophylline, haemoperfusion was used to reduce rapidly theophylline levels. Both patients recovered rapidly.

Active treatment of children with end-stage renal failure.

Chronic renal failure affects 1.5 children per million of the population each year. Most of these children are suitable for renal replacement therapy with the primary aim being full rehabilitation by means of a successful renal transplant. Since May 1974 12 children under the age of 16 years have entered the Christchurch dialysis-transplant programme. Six children had reflux nephropathy. Medullary cystic disease caused renal failure at the same time in identical twin girls. Dialysis was tolerated as a necessary step to transplantation. Major problems associated with home haemodialysis were the needling of the arteriovenous and the disruption of family life. After a successful transplant the children had few limitations. Chronic renal failure and its treatment in childhood were associated with growth retardation, delayed puberty and uncertainty regarding the future. With support from the family and friends these children attempted to lead a normal life.

The treatment of chronic renal failure in New Zealand.

The treatment of chronic renal failure by centre haemodialysis and home haemodialysis are described. Since 1969 there has been a home dialysis programme at Christchurch. Some 63 patients were treated and 17 have died, six deaths occurred during training, four died after renal transplantation and seven died of other causes. The training time was on average 15 weeks. The implications of this form of management are discussed.