Madhukar Misra

The basics of hemodialysis equipment

The hemodialysis (HD) machine pumps the dialysate as well as the patient’s blood through a dialyzer. The blood and dialysate are separated from each other by a semipermeable membrane permitting solute and water transfer as governed by laws of physics. In practice, however, this procedure is somewhat more complex. The operational system of the HD machine represents a complex array of detectors, controllers, monitors, and safety devices to ensure a safe operation. This integrated system allows the operator the ability to control the blood and the dialysate circuits as well as monitor important variables like ultrafiltration (UF) rate, adequacy, dialysate composition, and circuit pressures. Although such advances make patient management somewhat easier for the nephrologist, they do not change the basic tenet of patient care—first to do no harm. Consequently, it is extremely important for the practicing nephrologist to recognize and understand the terminology, significance, and management of the basic operational mechanics of HD machines. This article will focus on essential principles of HD equipment that are necessary for ensuring a safe, standard HD procedure (the description of equipment for other specialized procedures like hemofiltration is beyond the scope of this review). From a practical point of view, it is often useful to divide the HD process into two main parts, that is, the blood circuit and the dialysate circuit. The standards for HD equipment in the United States are set by the AAMI (Association for the Advancement of Medical Instrumentation). GENERAL GUIDELINES GOVERNING THE USE OF HD EQUIPMENT

Bath salt intoxication causing acute kidney injury requiring hemodialysis

Traditional bath salts contain a combination of inorganic salts like Epsom salts, table salt, baking soda, sodium metaphosphate, and borax that have cleansing properties. Since 2010, there have been rising concerns about a new type of substance abuse in the name of “bath salts.” They are beta‐ketone amphetamine analogs and are derivates of cathinone, a naturally occurring amphetamine analog found in the “khat” plant (Catha edulis). Effects reported with intake included increased energy, empathy, openness, and increased libido. Serious adverse effects reported with intoxication included cardiac, psychiatric, and neurological signs and symptoms. Not much is known about the toxicology and metabolism of these compounds. They inhibit monoamine reuptake (dopamine, nor epinephrine, etc.) and act as central nervous system stimulants with high additive and abuse potential because of their clinical and biochemical similarities to effects from use of cocaine, amphetamine, and 3,4‐methylenedioxy‐N‐methylamphetamine. Deaths associated with use of these compounds have also been reported. We report a case of acute kidney injury associated with the use of “bath salt” pills that improved with hemodialysis.

Role of plasmapheresis in the management of myeloma kidney: A systematic review

Multiple myeloma complicated by acute renal failure is a diagnosis often encountered by the practicing nephrologist. The role of plasmapheresis in such patients has been of interest for decades. Three randomized controlled trials (RCTs) and multiple observational trials have evaluated the potential role of plasmapheresis in the management of this condition. This systematic review presents the results of these trials regarding survival benefits, recovery from dialysis, and improvement in renal function. A comprehensive search revealed 56 articles. Of these, only 8 articles met our inclusion criteria (3 RCTs, 1 correction of results, and 4 observational trials). Two of the 3 RCTs showed no difference in survival benefit. Two of the 3 RCTs showed a greater percentage of patients stopping dialysis in the intervention group; however, these results were not reproduced in the largest trial. All the studies showed an improvement in renal function for patients receiving plasmapheresis; however, only 2 RCTs and 1 retrospective study showed a statistically significant improvement in renal function among patients who received plasmapheresis in comparison with a control group. Our systematic review does not suggest a benefit of plasmapheresis independent of chemotherapy for multiple myeloma patients with acute renal failure in terms of overall survival, recovery from dialysis, or improvement in renal function.

Myocardial stunning in hemodialysis: What is the overall message?

Heart failure and cardiovascular events are common in chronic renal failure. Hemodialysis (HD) causes significant hemodynamic changes and hypotension. New evidence based on intradialytic echocardiography demonstrates transient cardiac dysfunction or stunning in majority of chronic HD patients. Over time, this group may progress to chronic heart failure and appears to predict higher cardiovascular events and mortality. Although the exact etiology is unclear, alterations in HD technique and cardiac medications may reduce this complication. We review the current understanding of acute cardiac stunning during HD and present a systematic management algorithm to optimizing overall outcomes in this high‐risk population.

Increasing home based dialysis therapies to tackle dialysis burden around the world: a position statement on dialysis economics from the 2nd Congress of the International Society for Hemodialysis

PHILIP KAM-TAO LI, WAI LUN CHEUNG, SING LEUNG LUI, CHRISTOPHER BLAGG, ALAN CASS, LAI SEONG HOOI, HO YUNG LEE, FRANCESCO LOCATELLI, TAO WANG, CHIH-WEI YANG, BERNARD CANAUD, YUK LUN CHENG, HUI LIN CHOONG, ANGEL L DE FRANCISCO, VICTOR GURA, KAZO KAIZU, PETER G KERR, UN I KUOK, CHI BON LEUNG, WAI-KEI LO, MADHUKAR MISRA, CHEUK CHUN SZETO, KWOK LUNG TONG, KRIANG TUNGSANGA, ROBERT WALKER, ANDREW KUI-MAN WONG, ALEX WAI-YIN YU, on behalf of the participants of THE ROUNDTABLE DISCUSSION ON DIALYSIS ECONOMICS in the SECOND CONGRESS OF THE INTERNATIONAL SOCIETY FOR HEMODIALYSIS (ISHD 2009)*

Fluid overload and acute kidney injury

Acute kidney injury is commonly encountered in critically ill patients, and is associated with worse outcomes. Fluid therapy is a key component in the management of these patients, often leading to fluid overload, especially in the setting of septic acute kidney injury. Emerging data overwhelmingly suggest that fluid overload in these patients may be associated with adverse outcomes. Management of such patients should include a strategy of early guided resuscitation, followed by careful assessment of fluid status, and early initiation of renal replacement therapy as soon as it is deemed safe, aiming for a neutral or negative fluid balance. This review will focus on the pathophysiological link between fluid overload and acute kidney injury, mechanisms of organ dysfunction in fluid overload, and strategies for management.

Dialysis in the Elderly

More and more elderly (>65 years) patients are now reaching end-stage renal disease (ESRD) due to better management of co-morbid diseases. There are complex medical issues that need to be addressed when managing ESRD in this patient group. The option of dialysis in the elderly is a viable one. However, it needs careful consideration of patients’ choices besides coexisting illnesses. Ideally, dialysis should prolong survival. However, an equally important issue is quality of life on dialysis. Life should be added to years and not years added to life. This often involves multidisciplinary input from various disciplines involved in patient care. Other than life on dialysis, the only other alternative is conservative management. Conservative management is not ‘passive palliative therapy’. Rather, it involves active management of various clinical issues in a sick and vulnerable patient who does not have age on his side. All elderly patients have unique issues and no generalizations can be made. However, careful analysis makes it possible to offer dialysis to the right patient in the elderly and very elderly (>75 years and beyond) subgroups.

Intracardiac access for hemodialysis: A case series

Maintenance of functioning vascular access has long been recognized as the Achilles heel of a patient undergoing hemodialysis (HD). A subset of patients on HD for endstage renal disease (ESRD) may progressively exhaust all forms of traditional vascular access. In these patients, exploration of nontraditional HD access sites becomes imperative and life saving. Although various nontraditional approaches exist to obtain emergent vascular access, the benefits of direct intracardiac catheters over others include the ability to use standard cuffed catheters, and the ability to function despite thrombosis or stenosis of the central venous system and vena cava. Since 2003, 3 patients with ESRD at our institution exhausted their traditional dialysis vascular access options. All 3 were not suitable candidates for peritoneal dialysis. Emergent and successful implantation of right atrial dialysis catheters was achieved in all patients, providing functioning HD access in a desperate situation.

Retrospective evaluation of renal Kt/Vurea at the initiation of long-term peritoneal dialysis at the University of Missouri: Relationships to longitudinal nutritional status on peritoneal dialysis

The purpose of this study was to examine the impact of low levels of residual renal function (RRF) on nutritional status in end-stage renal disease patients starting peritoneal dialysis (PD) at baseline and after a year on dialysis. We conducted a single center retrospective analysis of 116 patients who started long-term PD in a university teaching hospital from 1989 to 1998 and were followed for 1 year. Patients were divided into four equal groups according to their initial renal Kt/Vurea (L/week) levels at the start of PD and followed for 1 year. There were no interventions. The relationship between dialysis adequacy (renal and total Kt/Vurea) and nutritional status was studied at baseline and at 1 year. Baseline data for patients who survived were compared with the baseline data of those who died and with their own 1 year data. At baseline, the mean serum albumin (3.31 g/dl, p < 0.0001) and lean body mass (47.20% body weight, p < 0.04) of group 1 were significantly lower than in groups 2, 3, and 4. Levels of normalized protein equivalent of nitrogen appearance (nPNA) were significantly lower in group 1 than in groups 3 and 4 (p < 0.005). Although group 1 patients showed trends toward improvement in nutritional parameters, they never caught up with the other groups. At the end of 1 year, the lower total Kt/Vurea in group 1, with the lowest RRF, was associated with the lowest mean values for nutritional status and the highest death rate. Comparison of baseline and 1 year data of survivors showed that nutritional status improved or remained stable in groups 3 and 4, who exceeded the minimum recommended adequacy targets as per Dialysis Outcome Quality Initiative criteria (mean 12 month total Kt/Vurea 2.18 and 2.58, respectively). Comparison of baseline data of survivors and those who died showed that patients who died had lower mean values for serum albumin, nPNA, lean body mass, and body weight across all groups. Low RRF at the start of dialysis is associated with poor nutritional status. Also, patients who start dialysis with low RRF and poor nutritional status do not have significantly improved nutritional status even after 1 year on dialysis.

Pro: Higher serum bicarbonate in dialysis patients is protective

Chronic metabolic acidosis is common in dialysis patients. Bicarbonate administration via the dialysate helps maintain the acid-base balance in these patients. Serum bicarbonate level in dialysis patients is determined by several factors that include dietary protein intake, nutritional status and dialysis prescription, etc. Additionally, a meaningful interpretation of serum bicarbonate in dialysis patients requires an understanding of complexities involving its measurement. Both very low as well very high levels of serum bicarbonate have been associated with adverse outcomes in observational studies. However, recent observational data, when adjusted for the confounding effects of nutritional status, do not associate higher predialysis serum bicarbonate with adverse consequences. At this time, there are no prospective studies available that have examined the association of serum bicarbonate with hard outcomes in dialysis patients. The ideal level of serum bicarbonate in dialysis patients is therefore unknown. This article examines the available data with regard to the benefits of higher predialysis serum bicarbonate.