Development of PD in lower-income countries: a rational solution for the management of AKI and ESKD

It is estimated that >50% of patients with end-stage kidney disease (ESKD) in low-resource countries are unable to access dialysis. When hemodialysis is available, it often has high out-of-pocket expenditure and is seldom delivered to the standard recommended by international guidelines. Hemodialysis is a high-cost intervention with significant negative effects on environmental sustainability, especially in resource-poor countries (the ones most likely to be affected by resultant climate change). This review discusses the rationale for peritoneal dialysis (PD) as a more resource and environmentally efficient treatment with the potential to improve dialysis access, especially to vulnerable populations, including women and children, in lower-resource countries. Successful initiatives such as the Saving Young Lives program have demonstrated the benefit of PD for acute kidney injury. This can then serve as a foundation for later development of PD services for end-stage kidney disease programs in these countries. Expansion of PD programs in resource-poor countries has proven to be challenging for various reasons. It is hoped that if some of these issues can be addressed, PD will be able to permit an expansion of end-stage kidney disease care in these countries.

ISPD Catheter-related Infection Recommendations: 2023 Update

Peritoneal dialysis (PD) catheter-related infections are important risk factors for catheter loss and peritonitis. The 2023 updated recommendations have revised and clarified definitions and classifications of exit site infection and tunnel infection. A new target for the overall exit site infection rate should be no more than 0.40 episodes per year at risk. The recommendation about topical antibiotic cream or ointment to catheter exit site has been downgraded. New recommendations include clarified suggestion of exit site dressing cover and updated antibiotic treatment duration with emphasis on early clinical monitoring to ascertain duration of therapy. In addition to catheter removal and reinsertion, other catheter interventions including external cuff removal or shaving, and exit site relocation are suggested.

Peritoneal Dialysis in Critically Ill Patients: Time for a Critical Reevaluation?

Peritoneal dialysis (PD) as an AKI treatment in adults was widely accepted in critical care settings well into the 1980s. The advent of extracorporeal continuous KRT led to widespread decline in the use of PD for AKI across high-income countries. The lack of familiarity and comfort with the use of PD in critical care settings has also led to lack of use even among those receiving maintenance PD. Many critical care units reflexively convert patients receiving maintenance PD to alternative dialysis therapies at admission. Renewed interest in the use of PD for AKI therapy has emerged due to its increasing use in low- and middle-income countries. In high-income countries, the coronavirus disease 2019 (COVID-19) pandemic, saw PD for AKI used early on, where many critical care units were in crisis and relied on PD use when resources for other AKI therapy modalities were limited. In this review, we highlight advantages and disadvantages of PD in critical care settings and indications and contraindications for its use. We provide an overview of literature to support both PD treatment during AKI and its continuation as a maintenance therapy during critical illness. For AKI therapy, we further discuss establishment of PD access, PD prescription management, and complication monitoring and treatment. Finally, we discuss expansion in the use of PD for AKI therapy extending beyond its role during times of resource constraints.

Access to Dialysis for Acute Kidney Injury in Low-Resource Settings

Acute kidney injury (AKI) is estimated to occur in approximately 13.3 million patients per year with an estimated mortality of 1.7 million. Approximately 85% of cases occur in low-resource settings where access to kidney replacement therapy (KRT) may be limited or nonexistent. The true extent of AKI, including access to KRT in developing countries, is largely unknown because appropriate systems are not in place to detect AKI or report it. Barriers to provision of KRT in low-resource settings revolve around systems management and funding, however, there also are region-specific issues. This review focuses on the epidemiology, obstacles, and solutions to improving access to KRT for AKI.

Peritoneal dialysis for acute kidney injury: back on the front-line

Peritoneal dialysis (PD) for acute kidney injury (AKI) has been available for nearly 80 years and has been through periods of use and disuse largely determined by availability of other modalities of kidney replacement therapy and the relative enthusiasm of clinicians. In the past 10 years there has been a resurgence in the use of acute PD globally, facilitated by promotion of PD for AKI in lower resource countries by nephrology organizations effected through the Saving Young Lives program and collaborations with the World Health Organisation, the development of guidelines standardizing prescribing practices and finally the COVID-19 pandemic. This review highlights the history of PD for AKI and looks at misconceptions about efficacy as well as the available evidence demonstrating that acute PD is a safe and lifesaving therapy with comparable outcomes to other modalities of treatment.

Peritoneal catheter insertion: combating barriers through policy change

Barriers to accessing home dialysis became a matter of life and death for many patients with kidney failure during the coronavirus disease 2019 (COVID-19) pandemic. Peritoneal dialysis (PD) is the more commonly used home therapy option. This article provides a comprehensive analysis of PD catheter insertion procedures as performed around the world today, barriers impacting timely access to the procedure, the impact of COVID-19 and a roadmap of potential policy solutions. To substantiate the analysis, the article includes a survey of institutions across the world, with questions designed to get a sense of the regulatory frameworks, barriers to conducting the procedure and impacts of the pandemic on capability and outcomes. Based on our research, we found that improving patient selection processes, determining and implementing correct insertion techniques, creating multidisciplinary teams, providing appropriate training and sharing decision making among stakeholders will improve access to PD catheter insertion and facilitate greater uptake of home dialysis. Additionally, on a policy level, we recommend efforts to improve the awareness and feasibility of PD among patients and the healthcare workforce, enhance and promulgate training for clinicians—both surgical and medical—to insert PD catheters and fund personnel, pathways and physical facilities for PD catheter insertion.

Experience with placing peritoneal dialysis catheters in the iliac fossa in cases of frozen pelvis

Peritoneal dialysis (PD) is a modality frequently preferred by patients for the management of their end-stage kidney disease; however, a major factor in its success is PD catheter placement and subsequent function. Optimal placement of PD catheters is generally accepted to be in the true pelvis, for this reason, many patients who are found to have a pelvic cavity obliterated by adhesions are often denied the opportunity to do PD. We report on four cases of an alternative advanced laparoscopic technique used in patients with inaccessible pelvic cavities, with three catheter placements in the intraperitoneal left iliac fossa/paracolic gutter and one case in the right paracolic gutter with subsequent good outcomes. This report suggests that a 'frozen pelvis' is not a contraindication to successful PD, with alternative catheter tip placement in the iliac fossa.

ISPD guidelines for peritoneal dialysis in acute kidney injury: 2020 Update (paediatrics)

SUMMARY OF RECOMMENDATIONS

1.1 Peritoneal dialysis is a suitable renal replacement therapy modality for treatment of acute kidney injury in children. (1C)2. Access and fluid delivery for acute PD in children.2.1 We recommend a Tenckhoff catheter inserted by a surgeon in the operating theatre as the optimal choice for PD access. (1B) (optimal)2.2 Insertion of a PD catheter with an insertion kit and using Seldinger technique is an acceptable alternative. (1C) (optimal)2.3 Interventional radiological placement of PD catheters combining ultrasound and fluoroscopy is an acceptable alternative. (1D) (optimal)2.4 Rigid catheters placed using a stylet should only be used when soft Seldinger catheters are not available, with the duration of use limited to <3 days to minimize the risk of complications. (1C) (minimum standard)2.5 Improvised PD catheters should only be used when no standard PD access is available. (practice point) (minimum standard)2.6 We recommend the use of prophylactic antibiotics prior to PD catheter insertion. (1B) (optimal)2.7 A closed delivery system with a Y connection should be used. (1A) (optimal) A system utilizing buretrols to measure fill and drainage volumes should be used when performing manual PD in small children. (practice point) (optimal)2.8 In resource limited settings, an open system with spiking of bags may be used; however, this should be designed to limit the number of potential sites for contamination and ensure precise measurement of fill and drainage volumes. (practice point) (minimum standard)2.9 Automated peritoneal dialysis is suitable for the management of paediatric AKI, except in neonates for whom fill volumes are too small for currently available machines. (1D)3. Peritoneal dialysis solutions for acute PD in children3.1 The composition of the acute peritoneal dialysis solution should include dextrose in a concentration designed to achieve the target ultrafiltration. (practice point)3.2  Once potassium levels in the serum fall below 4 mmol/l, potassium should be added to dialysate using sterile technique. (practice point) (optimal) If no facilities exist to measure the serum potassium, consideration should be given for the empiric addition of potassium to the dialysis solution after 12 h of continuous PD to achieve a dialysate concentration of 3-4 mmol/l. (practice point) (minimum standard)3.3  Serum concentrations of electrolytes should be measured 12 hourly for the first 24 h and daily once stable. (practice point) (optimal) In resource poor settings, sodium and potassium should be measured daily, if practical. (practice point) (minimum standard)3.4  In the setting of hepatic dysfunction, hemodynamic instability and persistent/worsening metabolic acidosis, it is preferable to use bicarbonate containing solutions. (1D) (optimal) Where these solutions are not available, the use of lactate containing solutions is an alternative. (2D) (minimum standard)3.5  Commercially prepared dialysis solutions should be used. (1C) (optimal) However, where resources do not permit this, locally prepared fluids may be used with careful observation of sterile preparation procedures and patient outcomes (e.g. rate of peritonitis). (1C) (minimum standard)4. Prescription of acute PD in paediatric patients4.1 The initial fill volume should be limited to 10-20 ml/kg to minimize the risk of dialysate leakage; a gradual increase in the volume to approximately 30-40 ml/kg (800-1100 ml/m²) may occur as tolerated by the patient. (practice point)4.2 The initial exchange duration, including inflow, dwell and drain times, should generally be every 60-90 min; gradual prolongation of the dwell time can occur as fluid and solute removal targets are achieved. In neonates and small infants, the cycle duration may need to be reduced to achieve adequate ultrafiltration. (practice point)4.3 Close monitoring of total fluid intake and output is mandatory with a goal to achieve and maintain normotension and euvolemia. (1B)4.4 Acute PD should be continuous throughout the full 24-h period for the initial 1-3 days of therapy. (1C)4.5  Close monitoring of drug dosages and levels, where available, should be conducted when providing acute PD. (practice point)5. Continuous flow peritoneal dialysis (CFPD)5.1   Continuous flow peritoneal dialysis can be considered as a PD treatment option when an increase in solute clearance and ultrafiltration is desired but cannot be achieved with standard acute PD. Therapy with this technique should be considered experimental since experience with the therapy is limited. (practice point) 5.2  Continuous flow peritoneal dialysis can be considered for dialysis therapy in children with AKI when the use of only very small fill volumes is preferred (e.g. children with high ventilator pressures). (practice point).

ISPD guidelines for peritoneal dialysis in acute kidney injury: 2020 update (adults)

SUMMARY STATEMENTS

(1) Peritoneal dialysis (PD) should be considered a suitable modality for treatment of acute kidney injury (AKI) in all settings (1B).

GUIDELINE 2: ACCESS AND FLUID DELIVERY FOR ACUTE PD IN ADULTS

(2.1) Flexible peritoneal catheters should be used where resources and expertise exist (1B) (optimal).(2.2) Rigid catheters and improvised catheters using nasogastric tubes and other cavity drainage catheters may be used in resource-poor environments where they may still be life-saving (1C) (minimum standard).(2.3) We recommend catheters should be tunnelled to reduce peritonitis and peri-catheter leak (practice point).(2.4) We recommend that the method of catheter implantation should be based on patient factors and locally available skills (1C).(2.5) PD catheter implantation by appropriately trained nephrologists in patients without contraindications is safe and functional results equate to those inserted surgically (1B).(2.6) Nephrologists should receive training and be permitted to insert PD catheters to ensure timely dialysis in the emergency setting (practice point). (2.7) We recommend, when available, percutaneous catheter insertion by a nephrologist should include assessment with ultrasonography (2C).(2.8) Insertion of PD catheter should take place under complete aseptic conditions using sterile technique (practice point).(2.9) We recommend the use of prophylactic antibiotics prior to PD catheter implantation (1B).(2.10) A closed delivery system with a Y connection should be used (1A) (optimal). In resource poor areas, spiking of bags and makeshift connections may be necessary and can be considered (minimum standard).(2.11) The use of automated or manual PD exchanges are acceptable and this will be dependent on local availability and practices (practice point).

GUIDELINE 3: PERITONEAL DIALYSIS SOLUTIONS FOR ACUTE PD

(3.1) In patients who are critically ill, especially those with significant liver dysfunction and marked elevation of lactate levels, bicarbonate containing solutions should be used (1B) (optimal). Where these solutions are not available, the use of lactate containing solutions is an alternative (practice point) (minimum standard).(3.2) Commercially prepared solutions should be used (optimal). However, where resources do not permit this, then locally prepared fluids may be life-saving and with careful observation of sterile preparation procedure, peritonitis rates are not increased (1C) (minimum standard).(3.3) Once potassium levels in the serum fall below 4 mmol/L, potassium should be added to dialysate (using strict sterile technique to prevent infection) or alternatively oral or intravenous potassium should be given to maintain potassium levels at 4 mmol/L or above (1C).(3.4) Potassium levels should be measured daily (optimal). Where these facilities do not exist, we recommend that after 24 h of successful dialysis, one consider adding potassium chloride to achieve a concentration of 4 mmol/L in the dialysate (minimum standard) (practice point).

GUIDELINE 4: PRESCRIBING AND ACHIEVING ADEQUATE CLEARANCE IN ACUTE PD

(4.1) Targeting a weekly K _t/V _urea of 3.5 provides outcomes comparable to that of daily HD in critically ill patients; targeting higher doses does not improve outcomes (1B). This dose may not be necessary for most patients with AKI and targeting a weekly K _t/V of 2.2 has been shown to be equivalent to higher doses (1B). Tidal automated PD (APD) using 25 L with 70% tidal volume per 24 h shows equivalent survival to continuous venovenous haemodiafiltration with an effluent dose of 23 mL/kg/h (1C).(4.2) Cycle times should be dictated by the clinical circumstances. Short cycle times (1-2 h) are likely to more rapidly correct uraemia, hyperkalaemia, fluid overload and/or metabolic acidosis; however, they may be increased to 4-6 hourly once the above are controlled to reduce costs and facilitate clearance of larger sized solutes (2C).(4.3) The concentration of dextrose should be increased and cycle time reduced to 2 hourly when fluid overload is evident. Once the patient is euvolemic, the dextrose concentration and cycle time should be adjusted to ensure a neutral fluid balance (1C).(4.4) Where resources permit, creatinine, urea, potassium and bicarbonate levels should be measured daily; 24 h K _t/V _urea and creatinine clearance measurement is recommended to assess adequacy when clinically indicated (practice point).(4.5) Interruption of dialysis should be considered once the patient is passing >1 L of urine/24 h and there is a spontaneous reduction in creatinine (practice point).

The use of peritoneal dialysis (PD) to treat patients with acute kidney injury (AKI) has become more popular among clinicians following evidence of similar outcomes when compared with other extracorporeal therapies. Although it has been extensively used in low-resource environments for many years, there is now a renewed interest in the use of PD to manage patients with AKI (including patients in intensive care units) in higher income countries. Here we present the update of the International Society for Peritoneal Dialysis guidelines for PD in AKI. These guidelines extensively review the available literature and present updated recommendations regarding peritoneal access, dialysis solutions and prescription of dialysis with revised targets of solute clearance.

Challenges of access to kidney care for children in low-resource settings

Kidney disease is a global public health concern across the age spectrum, including in children. However, our understanding of the true burden of kidney disease in low-resource areas is often hampered by a lack of disease awareness and access to diagnosis. Chronic kidney disease (CKD) in low-resource settings poses multiple challenges, including late diagnosis, the need for ongoing access to care and the frequent unavailability of costly therapies such as dialysis and transplantation. Moreover, children in such settings are at particular risk of acute kidney injury (AKI) owing to preventable and/or reversible causes - many children likely die from potentially reversible kidney disease because they lack access to appropriate care. Acute peritoneal dialysis (PD) is an important low-cost treatment option. Initiatives, such as the Saving Young Lives programme, to train local medical staff from low-resource areas to provide care for AKI, including acute PD, have already saved hundreds of children. Future priorities include capacity building for both educational purposes and to provide further resources for AKI management. As local knowledge and confidence increase, CKD management strategies should also develop. Increased awareness and advocacy at both the local government and international levels will be required to continue to improve the diagnosis and treatment of AKI and CKD in children worldwide.

Development of a framework for minimum and optimal safety and quality standards for hemodialysis and peritoneal dialysis

Substantial heterogeneity in practice patterns around the world has resulted in wide variations in the quality and type of dialysis care delivered. This is particularly so in countries without universal standards of care and governmental (or other organizational) oversight. Most high-income countries have developed such oversight based on documentation of adherence to standardized, evidence-based guidelines. Many low- and lower-middle-income countries have no or only limited organized oversight systems to ensure that care is safe and effective. The implementation and oversight of basic standards of care requires sufficient infrastructure and appropriate workforce and financial resources to support the basic levels of care and safety practices. It is important to understand how these standards then can be reasonably adapted and applied in low- and lower-middle-income countries.

Considerations on equity in management of end-stage kidney disease in low- and middle-income countries

Achievement of equity in health requires development of a health system in which everyone has a fair opportunity to attain their full health potential. The current, large country-level variation in the reported incidence and prevalence of treated end-stage kidney disease indicates the existence of system-level inequities. Equitable implementation of kidney replacement therapy (KRT) programs must address issues of availability, affordability, and acceptability. The major structural factors that impact equity in KRT in different countries are the organization of health systems, overall health care spending, funding and delivery models, and nature of KRT prioritization (transplantation, hemodialysis or peritoneal dialysis, and conservative care). Implementation of KRT programs has the potential to exacerbate inequity unless equity is deliberately addressed. In this review, we summarize discussions on equitable provision of KRT in low- and middle-income countries and suggest areas for future research.

Peritoneal Dialysis to Treat Patients with Acute Kidney Injury—The Saving Young Lives Experience in West Africa: Proceedings of the Saving Young Lives Session at the First International Conference of Dialysis in West Africa, Dakar, Senegal, December 2015

In December 2015, as part of the First African Dialysis Conference organized in Dakar, Senegal, 5 physicians from West African countries who have participated in the Saving Young Lives Program reviewed their experiences establishing peritoneal dialysis (PD) programs to treat patients with acute kidney injury (AKI). Thus far, nearly 200 patients have received PD treatment in these countries. The interaction and discussion amongst the participants at the meeting was meaningful and informative. The presentations highlighted the creativity, conviction, and determination of the physicians in overcoming the various barriers and challenges they encountered to establish PD/AKI programs. Hopefully, these successes and the increased awareness of the importance of early diagnosis and treatment of AKI will inspire much needed support from government, hospital, and international organizations.

Allograft and patient survival after sequential HSCT and kidney transplantation from the same donor-A multicenter analysis

Tolerance induction through simultaneous hematopoietic stem cell and renal transplantation has shown promising results, but it is hampered by the toxicity of preconditioning therapies and graft-versus-host disease (GVHD). Moreover, renal function has never been compared to conventionally transplanted patients, thus, whether donor-specific tolerance results in improved outcomes remains unanswered. We collected follow-up data of published cases of renal transplantations after hematopoietic stem cell transplantation from the same donor and compared patient and transplant kidney survival as well as function with caliper-matched living-donor renal transplantations from the Austrian dialysis and transplant registry. Overall, 22 tolerant and 20 control patients were included (median observation period 10 years [range 11 months to 26 years]). In the tolerant group, no renal allograft loss was reported, whereas 3 were lost in the control group. Median creatinine levels were 85 μmol/l (interquartile range [IQR] 72-99) in the tolerant cohort and 118 μmol/l (IQR 99-143) in the control group. Mixed linear-model showed around 29% lower average creatinine levels throughout follow-up in the tolerant group (P < .01). Our data clearly show stable renal graft function without long-term immunosuppression for many years, suggesting permanent donor-specific tolerance. Thus sequential transplantation might be an alternative approach for future studies targeting tolerance induction in renal allograft recipients.

Acute PD: Evidence, Guidelines, and Controversies☆

Peritoneal dialysis (PD) may be a feasible, safe, and complementary alternative to hemodialysis not only in the chronic setting, but also in the acute setting. It previously was widely accepted for acute kidney injury (AKI) treatment, but its practice decreased in favor of other types of extracorporeal therapies. The interest in PD to manage AKI patients has been reignited and PD now frequently is used in developing countries because of its lower cost and minimal infrastructural requirements. Studies from these countries have shown that, with careful thought and planning, critically ill patients can be treated successfully using PD. Some of the classic limitations of PD use in AKI, such as a high chance of infectious and mechanical complications and poor metabolic control, have been overcome with the use of cyclers, flexible catheters, and a high volume of dialysis fluid. However, in developing countries the infrastructure for quality research often is lacking and the result has been limited evidence on standardized treatment regimens such as indications, dosing, and technical failure and mortality. The recent publication of the International Society for Peritoneal Dialysis guidelines for PD in AKI have tried to address these issues and provide an evidence-based standard by which to initiate therapy. In this article, advances in technical aspects and the advantages and limitations of PD are discussed, and recent literature on clinical experience with PD for the treatment of AKI patients is reviewed.

Sirolimus-Induced Remission of Posttransplantation Lymphoproliferative Disorder

Posttransplantation lymphoproliferative disorder (PTLD) is one of the most serious complications of solid-organ transplantation. It potentially is treatable in most cases, but current methods involve withdrawal or reduction of immunosuppression and the consequent risk for graft rejection. Sirolimus was shown in vivo and in vitro to limit proliferation of a number of malignant cell lines, including those of PTLD-derived cells. We present a case of disseminated PTLD in a patient with a renal transplant that resolved completely with conversion of immunosuppression to sirolimus. Graft function was maintained and improved with treatment. This offers a novel means of treating these patients and minimizing transplant loss.

Bilateral collecting duct carcinoma presenting with tumour associated nephritis and end-stage renal failure. A case report and review of the literature

We present a 55 year old male who was investigated for painless macroscopic haematuria and had essentially normal radiological and cystoscopic findings. He progressed rapidly and was eventually diagnosed with a Collecting Duct Carcinoma. This case is of interest as it is the first reported case of Collecting Duct Carcinoma occurring bilaterally. It is also the first case to cause end stage renal failure requiring dialysis due to extensive tubular involvement. Finally, it is the first time this malignancy has been found to cause a tumour associated nephritis. We describe the clinical course and present the various histological findings followed by a review of the literature.

Analyzing variety by environment data using multiplicative mixed models and adjustments for spatial field trend

The recommendation of new plant varieties for commercial use requires reliable and accurate predictions of the average yield of each variety across a range of target environments and knowledge of important interactions with the environment. This information is obtained from series of plant variety trials, also known as multi-environment trials (MET). Cullis, Gogel, Verbyla, and Thompson (1998) presented a spatial mixed model approach for the analysis of MET data. In this paper we extend the analysis to include multiplicative models for the variety effects in each environment. The multiplicative model corresponds to that used in the multivariate technique of factor analysis. It allows a separate genetic variance for each environment and provides a parsimonious and interpretable model for the genetic covariances between environments. The model can be regarded as a random effects analogue of AMMI (additive main effects and multiplicative interactions). We illustrate the method using a large set of MET data from a South Australian barley breeding program.

Factors contributing to reduced productivity of subterranean clover (Trifolium subterraneum L.) pastures on acidic soils

In a field study on four sites, soil acidity, root rot (Phytophthora clandestina), and soil phosphorus were identified as causes of 'subterranean clover decline'. Liming increased herbage and seed production at four sites, with a tendency for lime to increase herbage yields in autumn (22%) and winter (15%) but not in spring. The presence of ryegrass with clover increased total herbage yields, and reduced clover seed production, but there was no interaction with liming. Losses caused by root rot associated with P. clandestina were quantified for the first time in New South Wales. Root rot reduced survival of seedlings as well as herbage production in autumn and/or winter at three of the four sites. In the presence of the disease, lime did not improve root health or seedling survival. On two sites with high aluminium saturation of exchangeable cations (> 17%) and high phosphorus sorption index values, subterranean clover growth responded to high levels of P fertilizer. On one site, where lime increased the soil pH to above 5.5, the P sorption index was temporarily increased, and this was associated with a temporary adverse effect on herbage yields. Some possible mechanisms underlying the seasonality of lime responses are proposed and the practical implications of our findings are discussed.

Effects of logging and fire on small mammals in Mumbulla State Forest, near Bega, New South Wales

This study of the effects of logging on small mammals in Mumbulla State Forest on the south coast of New South Wales included the effects of a fire in November 1980 and a drought throughout the study period from June 1980 to June 1983. Rattus fuscipes was sensitive to change: logging had a significant impact on its numbers, response to ground cover, and recapture rate; fire had a more severe effect, and drought retarded the post-fire recovery of the population. The three species of dasyurid marsupials differed markedly in their response to ground cover, canopy cover, logging and fire. Antechinus stuartii was distributed evenly through all habitats and was not affected by logging, but fire had an immediate and adverse effect which was sustained by the intense drought. A. swainsonii markedly preferred the regenerating forest, and was not seen again after the fire, the failure of the population being attributed to its dependence on dense ground cover. Sminthopsis leucopus was found in low numbers, appeared to prefer forest with sparse ground cover, and showed no immediate response to logging or fire; its disappearance by the third year post-fire suggests that regenerating forest is inimical to the survival of this species. Mus musculus showed no response to logging. In the first year following the fire its numbers were still very low, but in the next year there was a short-lived plague which coincided with the only respite in the 3-year drought and, importantly, occurred in the intensely burnt parts of the forest. The options for managing this forest for the conservation of small mammals include minimising fire, retaining unlogged forest, extending the time over which alternate coupes are logged and minimising disturbance from heavy machinery.

Effect of rootstock on the production, grape and wine quality of Shiraz vines in the Murrumbidgee Irrigation Area

The grape production and grape and wine quality of Shiraz vines, grown either on their own roots or on 6 rootstocks that have varying resistance to nematodes, were compared. Vines on the rootstocks Ramsey and Dog Ridge outyielded ungrafted vines by 46 and 48%, respectively, principally because of increased vegetative growth and hence retention of more nodes at pruning. Ramsey rootstock gave a greater grape yield per shoot. The ability of Dog Ridge stocks to produce yields as high as those of Ramsey highlights the importance of adequate pruning levels to enable the full potential of rootstocks to be determined. Vines on the rootstock Dog Ridge produced wines with higher pH values than wines from ungrafted control vines. Nematode counts suggested that the Vitus champini stocks have good tolerance to both rootknot and root lesion nematodes.

Tolerances of wheat cultivars to post-emergence wild oat herbicides

Sixteen spring wheat cultivars were tested in southern New South Wales for their tolerances to the recommended rates, and three times the recommended rates, and three times the recommended rates of barban, diclofop-methyl, difenzoquat and flamprop-methyl in 1978 and 1979. Differences between cultivars in their tolerances to barban and diclofop-methyl were identified in the grain yield responses to three times the recommended rates of these herbicides. Crop damage was more severe in 1978 than 1979. Olympic, Shortim, Teal and Warimba were consistently susceptible to barban, while Condor, Cook, Egret and Oxley were more tolerant than the other cultivars. The differences between cultivars treated with diclofop-methyl were smaller and variable. However, Lance, Teal and Tincurrin were the most sensitive whilst Cook, Kewell and Oxley showed the greatest tolerance. Visual assessments of crop damage did not accurately reflect crop tolerance, therefore grain yield should be used to identify susceptible cultivars.