Hemodialysis: Core Curriculum 2014

Abstract

Kidney dialysis evolves as we learn more about the uremic condition. At its earliest versions the major transport process was diffusion, the spontaneous movement of particles down a concentration gradient, stimulated by thermal agitation, and affected by the collision of the particles with each other and with barriers such as dialysis membrane pore side walls. As dialysis was utilized to replace kidney function ultrafiltration (UF) was required, which could be generated by osmotic, oncotic, or hydrostatic pressures. Consequently, solvent drag effects of the UF led to an appreciation of the importance of convective transport and its advantageous property of increasing the removal of larger molecular sized (molecular weight + steric hindrance effects) species. Thus, modern dialysis generally utilizes both diffusive and convective transport and current devices and equipment allow for either process to occur independently or in combination. However, during convection solute is removed but concentrations in the retentate may not decrease unless substitution fluid is administered, a process called hemofiltration. Diffusion can occur without any UF. Appreciation of these extremes is important to the understanding of modern dialysis. Currently, dialysis cannot replace the endocrine or metabolic functions of the kidney so our discussion will be restricted to solute and fluid removal.

Anticoagulation in Chronic Hemodialysis: Progress Toward an Optimal Approach

“…Clinical practice guidelines on anticoagulation for chronic HD have been developed by nephrology societies in Europe, United Kingdom, United States, Canada, Australasia, and Japan . The Canadian Society Hemodialysis Clinical Practice Guidelines have simply stated that adequate anti‐coagulation may be used to increase urea clearance and possibly dialysis adequacy .…”

Dialysis-Related Acidemia and Acidosis by Dialysate: The Forgotten Issue of CO₂ Overload from Dialysate

“…After mixing of the acid concentrate with the bicarbonate-containing solution, the pCO 2 in the dialysate ranges between 80 and 100 mm Hg [3,6,7], whereas arterial pCO 2 commonly is below 40 mm Hg (as a result of the ventilatory response to the metabolic acidosis in kidney failure). This leads to high CO 2 dialysance and thus to a sizable increase in pCO 2 in rial line is due to CO 2 load from dialysate overcoming CO 2 removal by the lung.…”

In‐center hemodialysis education: Challenges and innovations in training of fellows in nephrology

“…The National Institute of Health and the National Kidney Foundation support the development of the Nephrology Core Curriculum series, which is freely accessible online and published in the American Journal of Kidney Disease. Articles in this series pertaining to hemodialysis include Hemodialysis: Core Curriculum 2014, Unique Considerations in Renal Replacement Therapy in Children: Core Curriculum 2014 and Management of the Hemodialysis Unit: Core Curriculum 2016 . These articles have often served as the mainstay for training development and review.…”