Adrian L. Buttimore

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/Vurea 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.

Future of home haemodialysis in Australia and New Zealand (Review Article)

SUMMARY:  Maintenance haemodialysis (HD) was pioneered in Seattle and rapidly became home‐based. When dialysis treatment began in Australia and New Zealand, home haemodialysis (HHD) became the predominant form of dialysis. When compared with in‐centre conventional dialysis, HHD is associated with superior survival and quality of life and is cheaper. There is currently significant interest in increasing the frequency and duration of dialysis and in providing more flexible dialysis regimens for patients. If the likely benefits of these treatment changes are to be fully realized HHD and self care HD services will need to expand. Dialysis units in Australia and New Zealand are better equipped than most to respond to this challenge.

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.

The Christchurch earthquake: Dialysis experience and emergency planning

On 22 February 2011, a large earthquake struck the Canterbury region in New Zealand. There was extensive damage to buildings and infrastructure. The following day 42 haemodialysis patients were flown to Auckland where they acutely dialysed through the efforts of the Auckland, Waitemata and Counties‐Manukau dialysis team. Patients and support people were subsequently distributed to a designated Upper North Island District Health Board for longer‐term ongoing dialysis care. The last evacuated haemodialysis patient returned to Christchurch on 9 May 2011. Surprisingly there was a dearth of crush syndrome patients requiring dialysis. The evacuation and reception of a large number of dialysis patients was a novel experience for the New Zealand dialysis community. A planning guide for dialysis emergency is available to assist with similar future natural disasters.

Changes in blood pressure and vasoactive hormones during volume expansion in stable patients on chronic haemodialysis

Summary: We studied changes in blood pressure (BP) and plasma hormones (atrial natriuretic peptide [ANP], brain natriuretic peptide [BNP], endothelin [ET], angiotensin [AII] and renin [PRA]) in four stable haemodialysis patients 48 h after a routine dialysis (basal stat), after volume expansion (4–7% above dry bodyweight) for 4 days then 48 h later following ultrafiltration. Blood pressure rose and plasma AII and PRA values fell with volume expansion and returned to baseline at the end of the study. Endothelin values were unchanged. Plasma ANP and BNP rose similarly in three patients and returned to near baseline levels after ultrafiltration. Sustained volume expansion over 4 days in dialysis patients is associated with an increase in BP, a marked elevation in plasma ANP and BNP but without change in ET.