Compliance in peritoneal dialysis : a qualitative study of renal nurses

End-stage renal failure is a life-threatening condition, often treated with home-based peritoneal dialysis (PD). PD is a demanding regimen, and the patients who practise it must make numerous lifestyle changes and learn complicated biomedical techniques. In our experience, the renal nurses who provide mostPDeducation frequently express concerns that patient compliance with their teaching is poor. These concerns are mirrored in the renal literature. It has been argued that the perceived failure of health professionals to improve compliance rates with PD regimens is because ‘compliance’ itself has never been adequately conceptualized or defined; thus, it is difficult to operationalize and quantify. This paper examines how a group of Australian renal nurses construct patient compliance with PD therapy. These empirical data illuminate how PD compliance operates in one practice setting; how it is characterized by multiple and often competing energies; and how ultimately it might be pointless to try to tame ‘compliance’ through rigid definitions and measurement, or to rigidly enforce it in PD patients. The energies involved are too fractious and might be better spent, as many of the more experienced nurses in this study argue, in augmenting the energies that do work well together to improve patient outcomes.

Polydipsia : a feature of peritoneal dialysis

Background Some dialysis patients fail to comply with their fluid restriction causing problems due to volume overload. These patients sometimes blame excessive thirst. There has been little work in this area and no work documenting polydipsia among peritoneal dialysis (PD) patients. Methods We measured motivation to drink and fluid consumption in 46 haemodialysis patients (HD), 39 PD patients and 42 healthy controls (HC) using a modified palmtop computer to collect visual analogue scores at hourly intervals. Results Mean thirst scores were markedly depressed on the dialysis day (day 1) for HD (P<0.0001). The profile for day 2 was similar to that of HC. PD generated consistently higher scores than HD day 1 and HC (P = 0.01 vs. HC and P<0.0001 vs HD day 1). Reported mean daily water consumption was similar for HD and PD with both significantly less than HC (P<0.001 for both). However, measured fluid losses were similar for PD and HC whilst HD were lower (P<0.001 for both) suggesting that the PD group may have underestimated their fluid intake. Conclusion Our results indicate that HD causes a protracted period of reduced thirst but that the population's thirst perception is similar to HC on the interdialytic day despite a reduced fluid intake. In contrast, the PD group recorded high thirst scores throughout the day and were apparently less compliant with their fluid restriction. This is potentially important because the volume status of PD patients influences their survival.

Disturbed appetite and nutrient intake in peritoneal dialysis patients

OBJECTIVE Malnutrition is common among peritoneal dialysis (PD) patients. Reduced nutrient intake contributes to this. It has long been assumed that this reflects disturbed appetite. We set out to define the appetite profiles of a group of PD patients using a novel technique. DESIGN Prospective, cross-sectional comparison of PD patients versus controls. SETTING Teaching hospital dialysis unit. PATIENTS 39 PD patients and 42 healthy controls. INTERVENTION Visual analog ratings were recorded at hourly intervals to generate daily profiles for hunger and fullness. Summary statistics were generated to compare the groups. Food intake was measured using 3-day dietary records. MAIN OUTCOME MEASURES Hunger and fullness profiles. Derived hunger and fullness scores. RESULTS Controls demonstrated peaks of hunger before mealtimes, with fullness scores peaking after meals. The PD profiles had much reduced premeal hunger peaks. A postmeal reduction in hunger was evident, but the rest of the trace was flat. The PD fullness profile was also flatter than in the controls. Mean scores were similar despite the marked discrepancy in the profiles. The PD group had lower peak hunger and less diurnal variability in their hunger scores. They also demonstrated much less change in fullness rating around mealtimes, while the mean and peak fullness scores were little different. The reported nutrient intake was significantly lower for PD. CONCLUSION The data suggest that PD patients normalize their mean appetite perception at a lower level of nutrient intake than controls, suggesting that patient-reported appetite may be misleading in clinical practice. There is a loss of the usual daily variation for the PD group, which may contribute to their reduced food intake. The technique described here could be used to assess the impact of interventions upon the abnormal PD appetite profile.

Compliance, normality and the patient on peritoneal dialysis

Monitoring and enhancing patient compliance with peritoneal dialysis (PD) is a recurring and problematic theme in the renal literature. A growing body of literature also argues that a failure to understand the patient's perspective of compliance may be contributing to these problems. The aim of this study was to understand the concept of compliance with PD from the patient's perspective. Using the case study approach recommended by Stake (1995), five patients on PD consented to in-depth interviews that explored the meaning of compliance in the context of PD treatment and lifestyle regimens recommended by health professionals. Participants also discussed factors that influenced their choices to follow, disregard, or refine these regimens. Results indicate that health professionals acting in alignment with individual patient needs and wishes, and demonstrating an awareness of the constraints under which patients operate and the strengths they bring to their treatment, may be the most significant issues to consider with respect to definitions of PD compliance and the development of related compliance interventions. Aspects of compliance that promoted relative normality were also important to the participants in this study and tended to result in greater concordance with health professionals' advice.

Compliance, peritoneal dialysis and chronic kidney disease : lessons from the literature

Poor patient compliance with peritoneal dialysis (PD) has significant adverse effects on morbidity and mortality rates in individuals with chronic kidney disease (CKD). It also adds to the resource burdens of healthcare services and providers. This paper explores the notion of PD compliance in patients with CKD with reference to the relevant published literature. The analysis of the literature reveals that ‘PD compliance’ is a complex and challenging construct for both patients and health professionals. There is no universal definition of compliance that is widely adopted in practice and research, and therefore a lack of consensus on how to determine ‘compliant’ patient outcomes. There are also multiple and interconnected determinants of PD compliance that are context-bound, which healthcare professionals must be aware of, and which makes producing consensus of measuring PD compliance difficult. The complexity of the interventions required to produce even a modest improvement in PD compliance, which are described in this paper, are significant. Compliance with PD and other treatments for CKD is a multidimensional, context-bound concept, that to date has tended to efface the role and needs of the renal patient. We conclude the paper with the implications for contemporary practice.

Oral intake and serum levels of ascorbic acid in continuous ambulatory peritoneal dialysis patients

Oral intake of ascorbic acid is essential for optimum health in human beings. Continuous ambulatory peritoneal dialysis (CAPD) patients have an increased need for ascorbic acid, because of increased loss through dialysate, reduced intake owing to nausea and loss of appetite, and increased oxidative stress. However, optimum intake is still controversial. We studied 50 clinically stable patients to determine the relationship between oral ascorbic acid intake and serum ascorbic acid (SAA) level. Total oral intake ranged from 28 mg daily to 412 mg daily. Only one patient had an oral intake of ascorbic acid below 60 mg per day. The SAA levels ranged from 1 mg/L to 36.17 mg/L. Although a strong correlation existed between intake and SAA (p < 0.001, R2 = 0.47), the variation in SAA at any given intake level was wide. Of the studied patients, 62% had an SAA < 8.7 mg/L, 40% had an SAA < 5.1 mg/L (below the level in a healthy population), and 12% had a level below 2 mg/L (scorbutic). None of the patients demonstrated clinical manifestations of scurvy. Our results show that, in CAPD patients, ascorbic acid deficiency can be reliably detected only with SAA measurements, and oral intake may influence SAA level. To maintain ascorbic acid in the normal range for healthy adults, daily oral intake needs to be increased above the U.S. recommended dietary allowance to 80-140 mg.

Identification of early-stage colorectal cancer patients at risk of relapse post-resection by immunobead reverse transcription-PCR analysis of peritoneal lavage fluid for malignant cells

Purpose: Colorectal cancer patients diagnosed with stage I or II disease are not routinely offered adjuvant chemotherapy following resection of the primary tumor. However, up to 10% of stage I and 30% of stage II patients relapse within 5 years of surgery from recurrent or metastatic disease. The aim of this study was to determine if tumor-associated markers could detect disseminated malignant cells and so identify a subgroup of patients with early-stage colorectal cancer that were at risk of relapse. Experimental Design: We recruited consecutive patients undergoing curative resection for early-stage colorectal cancer. Immunobead reverse transcription-PCR of five tumor-associated markers (carcinoembryonic antigen, laminin γ2, ephrin B4, matrilysin, and cytokeratin 20) was used to detect the presence of colon tumor cells in peripheral blood and within the peritoneal cavity of colon cancer patients perioperatively. Clinicopathologic variables were tested for their effect on survival outcomes in univariate analyses using the Kaplan-Meier method. A multivariate Cox proportional hazards regression analysis was done to determine whether detection of tumor cells was an independent prognostic marker for disease relapse. Results: Overall, 41 of 125 (32.8%) early-stage patients were positive for disseminated tumor cells. Patients who were marker positive for disseminated cells in post-resection lavage samples showed a significantly poorer prognosis (hazard ratio, 6.2; 95% confidence interval, 1.9-19.6; P = 0.002), and this was independent of other risk factors. Conclusion: The markers used in this study identified a subgroup of early-stage patients at increased risk of relapse post-resection for primary colorectal cancer. This method may be considered as a new diagnostic tool to improve the staging and management of colorectal cancer. © 2006 American Association for Cancer Research.

Prediction of pull-out force of multi-walled carbon nanotube (MWCNT) in sword-in-sheath mode

The pull-out force of some outer walls against other inner walls in multi-walled carbon nanotubes (MWCNTs) was systematically studied by molecular mechanics simulations. The obtained results reveal that the pull-out force is proportional to the square of the diameter of the immediate outer wall on the sliding interface, which highlights the primary contribution of the capped section of MWCNT to the pull-out force. A simple empirical formula was proposed based on the numerical results to predict the pull-out force for an arbitrary pull-out in a given MWCNT directly from the diameter of the immediate outer wall on the sliding interface. Moreover, tensile tests for MWCNTs with and without acid-treatment were performed with a nanomanipulator inside a vacuum chamber of a scanning electron microscope (SEM) to validate the present empirical formula. It was found that the theoretical pull-out forces agree with the present and some previous experimental results very well.

Vitamin D intake, sun exposure and 25-hydroxy vitamin D status in Peritoneal dialysis (PD) and Haemodialysis (HD) patients

Inadequate vitamin D levels have been linked to bone disease but more recently have been associated with wider health implications. Limited studies suggest a high prevalence of Vitamin D deficiency in dialysis patients, although evidence is lacking on whether this is due to dietary restrictions, limited mobility and time outdoors or a combination of these. The aim of this study was to assess the contributions of diet, supplements and sunlight exposure to serum Vitamin D (25(OH)D) levels in dialysis patients. Cross-sectional data were obtained from 30 PD (Mean±SD age 56.9±16.2 y; n=13 male) and 22 HD (Mean±SD age 65.4±14.0 y; n=18 male) patients between 2009 and 2010. Serum 25(OH)D was measured and oral vitamin D intake estimated through a food-frequency-questionnaire and quantifying inactive supplementation. Sunlight exposure was assessed using a validated questionnaire. Prevalence of inadequate/insufficient vitamin D differed between dialysis modality (31% and 43% insufficient (<50nmol/L); 4% and 34% deficient (<25nmol/L) in HD and PD patients respectively (p=0.002)). In HD patients, there was a significant correlation between diet plus supplemental vitamin D intake and 25(OH)D (ρ=0.84, p<0.001). Results suggest a higher frequency of 25(OH)D inadequacy/deficiency in PD compared to HD patients. No other relationships between intake, sun exposure and 25(OH)D were seen. This could reflect limitations of the study design or the importance of other factors such as age, ethnicity and sun protection as interactions in the analysis. Understanding these factors is important given Vitamin D’s emerging status as a biomarker of systemic ill health.

Heating and plasma sheath effects in low-temperature, plasma-assisted growth of carbon nanofibers

Plasma sheath, nanostructure growth, and thermal models are used to describe carbon nanofiber (CNF) growth and heating in a low-temperature plasma. It is found that when the H2 partial pressure is increased, H atom recombination and H ion neutralization are the main mechanisms responsible for energy release on the catalyst surface. Numerical results also show that process parameters such as the substrate potential, electron temperature and number density mainly affect the CNF growth rate and plasma heating at low catalyst temperatures. In contrast, gas pressure, ion temperature, and the C2H2:H2 supply ratio affect the CNF growth at all temperatures. It is shown that plasma-related processes substantially increase the catalyst particle temperature, in comparison to the substrate and the substrate-holding platform temperatures.

Structure of the magnetized sheath of a dusty plasma

A three-component fluid model for a dusty plasma-sheath in an oblique magnetic field is presented. The study is carried out for the conditions when the thermophoretic force associated with the electron temperature gradient is one of the most important forces affecting dust grains in the sheath. It is shown that the sheath properties (the sheath size, the electron, ion and dust particle densities and velocities, the electric field potential, and the forces affecting the dust particles) are functions of the neutral gas pressure and ion temperature, the dust size, the dust material density, and the electron temperature gradient. Effects of plasma-dust collisions on the sheath structure are studied. It is shown that an increase in the forces pushing dust particles to the wall is accompanied by a decrease in the sheath width. The results of this work are particularly relevant to low-temperature plasma-enabled technologies, where effective control of nano- and microsized particles near solid or liquid surfaces is required.