Review: Understanding sorbent dialysis systems

Although maintenance haemodialysis once had the benefit of two distinctly different dialysate preparation and delivery systems – (1) a pre‐filtration and reverse osmosis water preparation plant linked to a single pass proportioning system and (2) a sorbent column dependent dialysate regeneration and recirculation system known as the REDY system – the first came to dominate the market and the second waned. By the early 1990s, the REDY had disappeared from clinical use. The REDY system had strengths. It was a small, mobile, portable and water‐efficient, only 6 L of untreated water being required for each dialysis. In comparison, single pass systems are bulky, immobile and water (and power) voracious, typically needing 400–600 L/treatment of expensively pretreated water. A resurgence of interest in home haemodialysis – short and long, intermittent and daily – has provided impetus to redirect technological research into cost‐competitive systems. Miniaturization, portability, flexibility, water‐use efficiency and ‘wearability’ are ultimate goals. Sorbent systems are proving an integral component of this effort. In sorbent dialysate regeneration, rather than draining solute‐rich dialyser effluent to waste – as do current systems – the effluent repetitively recirculates across a sorbent column capable of adsorption, ion exchange or catalytic conversion of all solute such that, at exit from the column, an ultra‐pure water solution emerges. This then remixes with a known electrolyte concentrate for representation to the dialyser. As the same small water volume can recirculate, at least until column exhaustion, water source independence is assured. Many current technological developments in dialysis equipment are now focusing on sorbent‐based dialysate circuitry. Although possibly déjà vu for some, it is timely for a brief review of sorbent chemistry and its application to dialysis systems.     

Antimicrobial resistance in Staphylococcus aureus in Australian teaching hospitals, 1989-1999

An annual survey of antimicrobial resistance in clinical isolates of Staphylococcus aureus was conducted in 21 Australian teaching hospital microbiology laboratories in eight major cities from 1989 to 1999. A total of 19,000 isolates were tested for susceptibility to 18 antimicrobials, with 3795 being methicillin-resistant (MRSA). Resistance to ciprofloxacin in MRSA increased from 4.9% to 75.9%. The proportion of MRSA resistant to erythromycin decreased significantly (99.0%-88.9%), as did that to trimethoprim (98.4%-82.4%) and to tetracycline (96.5%-80.1%). The proportion of MRSA isolated increased in Sydney, Melbourne, Canberra, Adelaide, Perth, and Darwin, but not in Brisbane. The proportion in Hobart peaked in 1994. MRSA in Perth were predominantly non-multiresistant (nmMRSA) throughout the survey (i.e., resistant to less than three of eight indicator antibiotics) due mainly to local strains that originated in the community. The proportion of nmMRSA increased to modest levels in the other cities. In eastern cities, this was due to the appearance of strains closely related to nmMRSA seen in other countries of the southwestern Pacific.     

An education programme promoting organ donation for 13–14 year old schoolchildren

Summary: Many programmes have attempted community education in organ donation. Too often these 'preach to the converted' or concentrate on special interest groups, thus failing to widely influence community perceptions of transplantation and organ donation.
As 13–14 year old children appear sufficiently mature to be receptive to challenging ideas yet may not yet have developed fixed biases or opinions to impair concept assimilation, an educational package dealing with dialysis/transplantation and organ donation was tested in two evenly aged, socio-economic and sex matched student groups at this age level in a single co-educational school. One group only was exposed to a 3 h comprehensive course in renal structure and function, dialysis and transplantation. the two groups were assessed 1 year later by questionnaire to test the retention of information and, more importantly, to compare attitudes to organ donation.
Statistically significant differences characterized the knowledge of and attitudes towards dialysis and transplantation between the two groups. In particular, the tutored group was much more likely to agree to organ donation by self ( P <0.009) or by relatives ( P <0.03) when compared to the untutored group.
This study demonstrates that a short, simple education course for 13–14 year old students can favourably change their perceptions and attitudes towards organ donation. the wider application of similar courses may have a positive impact upon dialysis and transplantation awareness and, ultimately, on national donor rates, becoming a useful addition to national strategies to increase organ donation.     

CONTINUOUS AMBULATORY PERITONEAL DIALYSIS (CAPD): AN ESTABLISHED TREATMENT FOR ENDSTAGE RENAL FAILURE

Abstract: This paper is a study of 117 patients with endstage renal failure, treated by continuous ambulatory peritoneal dialysis (CAPD) over periods of 1–56 months. The study has shown CAPD to be an effective form of dialysis with a number of advantages over intermittent peritoneal dialysis and hemodialysis (better control of salt and water status, hypertension and anemia, steady state biochemistry and greater ease of self-dialysis). Peritoneal clearance and ultrafiltration have remained adequate in all but a few patients. Hypoproteinemia, poor nutrition, obesity and abdominal herniae have been problems in a small percentage of patients. Hyperlipidemia has developed in half the patients but improved with diet. Peritonitis remains the major barrier to the more widespread use of CAPD, although its incidence can be considerably reduced by use of better connectors, bacterial filters and choice of patients.     

Measuring the outcome of psychosocial intervention for family caregivers of dementia sufferers: A factor analytic study

There is an increasing demand for measures which permit the assessment of the effectiveness of psychosocial interventions in community care. Existing measures of objective and subjective burden have limited utility because they have not been adequately psychometrically evaluated. A full psychometric evaluation of two commonly used measures of objective and subjective burden was conducted amongst 114 dementia caregivers. The patterns of association obtained between the two measures suggest that the use of this technique in caregiver assessment may assist in the targeting of appropriate interventions.