Continuous renal replacement therapy: current practice in Australian and New Zealand intensive care units

BACKGROUND: Large multicentre studies of continuous renal replacement therapy (CRRT) in critically ill patients may influence its bedside prescription and practical application. Despite this, many aspects of CRRT may not be informed by evidence but remain a product of clinician preference. Little was known about current CRRT practice in Australia and New Zealand and it is not known if the evidence from recent studies has been integrated into practice. DESIGN AND SETTING: A prospective online survey of CRRT practice was sent to intensive care unit medical and nursing clinicians via three national databases in Australian and New Zealand ICUs in December 2013 to March 2014. RESULTS: There were 194 respondents from 106 ICUs; 49 ICUs (47%) were in tertiary metropolitan hospitals. One hundred and two respondents (54%) reported continuous venovenous haemodiafiltration as the most common CRRT technique, with a combination of predilution and postdilution of CRRT solutions. The prescription for CRRT was variable, with respondents indicating preferences for therapy based on L/hour (53%) or a weight-adjusted treatment in mL/kg/hour (47%). For all modes of CRRT, the common blood flow rates applied were 151-200mL/ minute and 201-250mL/minute. Few respondents reported preferring flow rates < 150 mL/minute or > 300mL/minute. Unfractionated heparin was the most commonly used anticoagulant (83%), followed by regional citrate. Femoral vein vascular access was preferred and, typically, a 20 cm length catheter was used. Bard Niagara and Arrow catheters were most frequently used. The Gambro Prismaflex was the dominant machine used (71%). CONCLUSIONS: Our results provide insight into existing clinical management of CRRT. There is considerable variation in the prescription of CRRT in Australian and New Zealand ICUs

Faster Blood Flow Rate Does Not Improve Circuit Life in Continuous Renal Replacement Therapy: A Randomized Controlled Trial

Objectives: To determine whether blood flow rate influences circuit life in continuous renal replacement therapy. Design: Prospective randomized controlled trial. Setting: Single center tertiary level ICU. Patients: Critically ill adults requiring continuous renal replacement therapy. Interventions: Patients were randomized to receive one of two blood flow rates: 150 or 250 mL/min. Measurements and Main Results: The primary outcome was circuit life measured in hours. Circuit and patient data were collected until each circuit clotted or was ceased electively for nonclotting reasons. Data for clotted circuits are presented as median (interquartile range) and compared using the Mann-Whitney U test. Survival probability for clotted circuits was compared using log-rank test. Circuit clotting data were analyzed for repeated events using hazards ratio. One hundred patients were randomized with 96 completing the study (150 mL/min, n = 49; 250 mL/min, n = 47) using 462 circuits (245 run at 150 mL/min and 217 run at 250 mL/min). Median circuit life for first circuit (clotted) was similar for both groups (150 mL/min: 9.1 hr [5.5–26 hr] vs 10 hr [4.2–17 hr]; p = 0.37). Continuous renal replacement therapy using blood flow rate set at 250 mL/min was not more likely to cause clotting compared with 150 mL/min (hazards ratio, 1.00 [0.60–1.69]; p = 0.68). Gender, body mass index, weight, vascular access type, length, site, and mode of continuous renal replacement therapy or international normalized ratio had no effect on clotting risk. Continuous renal replacement therapy without anticoagulation was more likely to cause clotting compared with use of heparin strategies (hazards ratio, 1.62; p = 0.003). Longer activated partial thromboplastin time (hazards ratio, 0.98; p = 0.002) and decreased platelet count (hazards ratio, 1.19; p = 0.03) were associated with a reduced likelihood of circuit clotting. Conclusions: There was no difference in circuit life whether using blood flow rates of 250 or 150 mL/min during continuous renal replacement therapy

Evaluation of Urea and Creatinine change during Continuous Renal Replacement Therapy: Effect of blood flow rate

OBJECTIVE: To determine if faster blood flow rate (BFR) has an effect on solute maintenance in continuous renal replacement therapy. DESIGN: Prospective randomised controlled trial. SETTING: 24-bed, single centre, tertiary level intensive care unit. PARTICIPANTS: Critically ill adults requiring continuous renal replacement therapy (CRRT). INTERVENTIONS: Patients were randomised to receive one of two BFRs: 150 mL/min or 250 mL/min. MAIN OUTCOME MEASURES: Changes in urea and creatinine concentrations (percentage change from baseline) and delivered treatment for each 12-hour period were used to assess solute maintenance. RESULTS: 100 patients were randomised, with 96 completing the study (49 patients, 150 mL/min; 47 patients, 250 mL/min). There were a total of 854 12-hour periods (421 periods, 150 mL/min; 433 periods, 250 mL/ min). Mean hours of treatment per 12 hours was 6.3 hours (standard deviation [SD], 3.7) in the 150 mL/min group, and 6.7 hours (SD, 3.9) in the 250 mL/min group (P = 0.6). There was no difference between the two BFR groups for change in mean urea concentration (150 mL/min group, –0.06%; SD, 0.015; v 250 mL/min group, –0.07%; SD, 0.01; P = 0.42) or change in mean creatinine concentration (150 mL/min, –0.05%; SD, 0.01; v 250 mL/min, –0.08%; SD, 0.01; P = 0.18). Independent variables associated with a reduced percentage change in mean serum urea and creatinine concentrations were low haemoglobin levels (–0.01%; SD, 0.005; P = 0.002; and 0.01%; SD, 0.005; P = 0.006, respectively) and less hours treated (–0.023%; SD, 0.001; P = 0.000; and –0.02%; SD, 0.002; P = 0.001, respectively). No effect for bodyweight was found. CONCLUSIONS: Faster BFR did not affect solute control in patients receiving CRRT; however, differences in urea and creatinine concentrations were influenced by serum haemoglobin and hours of treatment

Mitochondrial Utilization of Competing Fuels Is Altered in Insulin Resistant Skeletal Muscle of Non-obese Rats (Goto-Kakizaki)

Aim: Insulin-resistant skeletal muscle is characterized by metabolic inflexibility with associated alterations in substrate selection, mediated by peroxisome-proliferator activated receptor δ (PPARδ). Although it is established that PPARδ contributes to the alteration of energy metabolism, it is not clear whether it plays a role in mitochondrial fuel competition. While nutrient overload may impair metabolic flexibility by fuel congestion within mitochondria, in absence of obesity defects at a mitochondrial level have not yet been excluded. We sought to determine whether reduced PPARδ content in insulin-resistant rat skeletal muscle of a non-obese rat model of T2DM (Goto-Kakizaki, GK) ameliorate the inhibitory effect of fatty acid (i.e., palmitoylcarnitine) on mitochondrial carbohydrate oxidization (i.e., pyruvate) in muscle fibers. Methods: Bioenergetic function was characterized in oxidative soleus (S) and glycolytic white gastrocnemius (WG) muscles with measurement of respiration rates in permeabilized fibers in the presence of complex I, II, IV, and fatty acid substrates. Mitochondrial content was measured by citrate synthase (CS) and succinate dehydrogenase activity (SDH). Western blot was used to determine protein expression of PPARδ, PDK isoform 2 and 4. Results: CS and SDH activity, key markers of mitochondrial content, were reduced by ∼10–30% in diabetic vs. control, and the effect was evident in both oxidative and glycolytic muscles. PPARδ (p < 0.01), PDK2 (p < 0.01), and PDK4 (p = 0.06) protein content was reduced in GK animals compared to Wistar rats (N = 6 per group). Ex vivo respiration rates in permeabilized muscle fibers determined in the presence of complex I, II, IV, and fatty acid substrates, suggested unaltered mitochondrial bioenergetic function in T2DM muscle. Respiration in the presence of pyruvate was higher compared to palmitoylcarnitine in both animal groups and fiber types. Moreover, respiration rates in the presence of both palmitoylcarnitine and pyruvate were reduced by 25 ± 6% (S), 37 ± 6% (WG) and 63 ± 6% (S), 57 ± 8% (WG) compared to pyruvate for both controls and GK, respectively. The inhibitory effect of palmitoylcarnitine on respiration was significantly greater in GK than controls (p < 10–3). Conclusion: With competing fuels, the presence of fatty acids diminishes mitochondria ability to utilize carbohydrate derived substrates in insulin-resistant muscle despite reduced PPARδ content

Blood flow rate and circuit life in continuous renal replacement therapy (CRRT): a randomised controlled trial (RCT)

Abstract of a paper presented to 'The 41st Australian and New Zealand Scientific meeting on Intensive Care', Perth, Australia, October 201

Using historical documentary methods to explore the history of occupational therapy

peer-reviewed.Introduction: Historical research can benefit health professions by providing a basis for understanding how current beliefs and practices developed over time. From an occupational therapy perspective, a need for deeper critical understandings of the profession has been identified; historical research can facilitate this process. Documentary research is a significant methodology in historical inquiry, but there is a dearth of guidance for occupational therapists wishing to employ this method. Method: A conceptual literature review was conducted to describe how to use documentary sources to understand the development of the profession, drawing on literature from the disciplines of history and occupational therapy. Results: The stages of historical documentary research are described: choosing a topic, sourcing and selecting evidence, and managing sources. How to consider the authenticity, credibility and representativeness of historical material is discussed. Various means to determine the meaning of historical evidence are considered, with chronological, thematic and theoretical approaches proposed. Conclusion: Methodological transparency is central to the process of historical documentary research. To enhance understanding of the quality of historical source material, adoption of the guidelines outlined is recommended. Adopting a clearly defined questioning perspective promotes more substantial conclusions and professional understandingspeer-reviewe

RESCALE: Review and Simulate Climate and Catchment Responses at Burrishoole

The climate of the Burrishoole catchment is projected to change significantly over the present century. Previous research of the catchment identified a scientific gap in knowledge in terms of understanding the implications of present and projected future changes in stream flow, water temperature, pH levels and DO concentrations on fish productivity in the catchment. To address this, a multidisciplinary team of scientists undertook an analysis of both present and likely future climate impacts on the catchment with a view to furthering the understanding of the inter-linkages between climate, climate change, and the freshwater ecosystem. The research findings outlined in the report provide climate change information at the catchment scale to assist catchment stakeholders in integrating climate change considerations into their decision-making processes. The report presents an in-depth assessment of the climate and environmental datasets from the catchment to establish if changes have occurred over the period of record. In order to assess the likely impacts of future changes in climate on the catchment, regional climate projections were developed and subsequently employed to simulate likely responses in stream flow and temperature, DOC and DO for the present century. The projected changes in both the climate and water-quality were then used to provide a basis for assessing impacts on fish growth and survival rates of salmonid and eel species in the catchment. The report provides a useful template for future studies, not just in the Burrishoole catchment but for other ecologically important catchments. The findings from the report are relevant to policy makers at the national scale; catchment managers at the regional scale; and, specifically, to stakeholders in the Burrishoole catchment, in developing adaptive responses to climate change.Funded under the Marine Research Sub-programme of the National Development Plan (2007-’13), as part of the Sea Change Strategy.Funder: Marine Institut

Technical Report: Review and Simulate Climate and Catchment Responses at Burrishoole (RESCALE)

Lead Partner: Department of Geography, National University of Ireland Maynooth Project Partners: School of Natural Sciences, Trinity College Dublin Marine Institute, Furnace, Newport, Co. MayoThis report demonstrates that the projected changes in the climate conditions of the Burrishoole catchment, if realised, will have wide ranging implications for all aspects of the catchment system, including water temperature and quality, stream flow hydrology, soil processes, and most notably the well-being of its aquatic environment. While the projected changes in climate and their implications, outlined in this report, are specific to the Burrishoole, they are illustrative of likely changes in similar characteristic catchments along the west coast of Ireland.Funder: Marine Institut

Caring international research collaborative: A five-country partnership to measure perception of nursing staffs' compassion fatigue, burnout, and caring for self

Partnering in research across disciplines and across countries can be challenging due to differing contexts of practice and culture. This study sought to demonstrate how central constructs that have application across disciplines and countries can be studied while concurrently considering context. Groups of nurses from Botswana, Ireland, Israel, New Zealand, and Spain partnered to identify how to measure the constructs of caring for self, burnout, and compassion fatigue, replicating a study by Johnson (2012), who found that caring for self had a moderately strong negative relationship with both compassion fatigue and burnout. While these constructs were of interest to all five groups, the conversation of contextual influences varied. All five groups used the same instruments to measure the central constructs. Levels of burnout and compassion fatigue varied by country but were moderated by caring for self. Partnering across countries made it possible to understand that caring for self moderates the negative impact of burnout and compassion fatigue in all five countries. This study gives insight into methods for partnering across disciplines and contexts