Association of dialysate bicarbonate concentration with mortality in the Dialysis Outcomes and Practice Patterns Study (DOPPS)

Sodium bicarbonate therapy in patients with metabolic acidosis

Metabolic acidosis occurs when a relative accumulation of plasma anions in excess of cations reduces plasma pH. Replacement of sodium bicarbonate to patients with sodium bicarbonate loss due to diarrhea or renal proximal tubular acidosis is useful, but there is no definite evidence that sodium bicarbonate administration to patients with acute metabolic acidosis, including diabetic ketoacidosis, lactic acidosis, septic shock, intraoperative metabolic acidosis, or cardiac arrest, is beneficial regarding clinical outcomes or mortality rate. Patients with advanced chronic kidney disease usually show metabolic acidosis due to increased unmeasured anions and hyperchloremia. It has been suggested that metabolic acidosis might have a negative impact on progression of kidney dysfunction and that sodium bicarbonate administration might attenuate this effect, but further evaluation is required to validate such a renoprotective strategy. Sodium bicarbonate is the predominant buffer used in dialysis fluids and patients on maintenance dialysis are subjected to a load of sodium bicarbonate during the sessions, suffering a transient metabolic alkalosis of variable severity. Side effects associated with sodium bicarbonate therapy include hypercapnia, hypokalemia, ionized hypocalcemia, and QTc interval prolongation. The potential impact of regular sodium bicarbonate therapy on worsening vascular calcifications in patients with chronic kidney disease has been insufficiently investigated.

Medication burden in CKD-5D: impact of dialysis modality and setting

BACKGROUND

Medication adherence is thought to be around 50% in the general and dialysis population. Reducing the pill burden (PB) reduces regime complexity and can improve adherence. Increased adherence should lead to improvement in treatment outcomes and patient quality of life. There is currently little published data on PB in CKD-5D across dialysis modalities.

METHODS

This is a retrospective, single renal network study. All in-centre HD (MHD), peritoneal dialysis (PD) and home HD (HHD) patients were identified in the Greater Manchester East sector renal network. Information collected included age, sex, comorbidities, daily PB, dialysis vintage and adequacy. Data were retrieved from a customized renal database, clinic and discharge letters with cross validation from the general practitioner when needed.

RESULTS

Two hundred and thirty-six prevalent dialysis patients were studied. HHD patients had a significantly lower PB (11 ± 7 pills/day) compared with PD and MHD (16 ± 7 pills/day). The HHD patients required fewer BP medications to meet the recommended target. HD setting was the only significant factor for reducing PB. For home therapies (HHD versus PD), weekly Kt/v and serum phosphate were significant factors influencing PB. When comparing all modalities, OR of PB ≥ 15/day for MHD versus HHD was 3.9 and PD versus HHD was 4.9. The influence of HHD is dominant above factors such as comorbidities or clinical variables in reducing PB for MHD. Higher clearances achieved by HHD could explain differences in PB with PD.

CONCLUSION

This is the first comparative study of PB across all dialysis modalities and factors that influence it. The PB advantage in HHD may result in greater adherence and might contribute to the outcome benefit often seen with this modality. Higher clearances achieved by HHD could explain differences in PB with PD but the precise reasons for lower PB remain speculative and deserve further research in larger settings.

Improving outcomes by changing hemodialysis practice patterns

PURPOSE OF REVIEW

This review examines recent advances in understanding of how clinical outcomes for hemodialysis patients may be improved by achieving longer or more frequent treatment times, lower ultrafiltration rates (UFRs), improving nutritional status, and individualizing dialysate composition. This review also discusses the controversy related to timing of dialysis initiation.

RECENT FINDINGS

Many observational studies and several randomized controlled trials indicate longer dialysis treatment times, particularly nocturnal dialysis, and/or more frequent dialysis improve morbidity and mortality. Recent evidence also suggests that lower UFR and more consistent achievement of 'dry weight' may help minimize the damage from myocardial stunning and chronic volume overload that occurs in the majority of patients who receive conventional hemodialysis during the day with a standard schedule of 3-5 h, 3 times a week. Other aspects of the dialysis procedure such as appropriate estimated glomerular filtration rate for dialysis initiation and individualizing dialysate composition may also minimize cardiovascular risk. Finally, several studies have highlighted the benefits of oral nutritional supplementation (ONS) during dialysis.

SUMMARY

Greater treatment times per week with slower UFR, consistent attainment of 'dry weight', individualized dialysate prescriptions, and administration of ONS to malnourished patients are likely to reduce hospitalizations and improve survival in this high-risk population of end-stage renal disease patients.

A patient with CKD and poor nutritional status

Protein energy wasting is common in patients with CKD and ESRD and is associated with adverse clinical outcomes, such as increased rates of hospitalization and death, in these patients. A multitude of factors can affect the nutritional and metabolic status of patients with CKD, including decreased dietary nutrient intake, catabolic effects of renal replacement therapy, systemic inflammation, metabolic and hormonal derangements, and comorbid conditions (such as diabetes and depression). Unique aspects of CKD also confound reliable assessment of nutritional status, further complicating management of this comorbid condition. In patients in whom preventive measures and oral dietary intake from regular meals cannot help them maintain adequate nutritional status, nutritional supplementation, administered orally, enterally, or parenterally, is effective in replenishing protein and energy stores. The advantages of oral nutritional supplements include proven efficacy, safety, and compliance. Anabolic steroids and exercise, with nutritional supplementation or alone, improve protein stores and represent potential additional approaches for the treatment of PEW. There are several emerging novel therapies, such as appetite stimulants, anti-inflammatory interventions, and anabolic agents.