Mod 1:Hybrid therapies

Hybrid Therapies

• Hybrid therapies combine characteristics of intermittent and continuous techniques for treatment frequency, duration, and modality
• They aim to optimize the benefits of both modalities, such as efficient solute removal and slower ultrafiltration for hemodynamic stability
• This reduces anti-coagulant exposure and lowers costs, along with decreasing nurse workload and improving ICU workflow

Blood Purification Strategies

• Strategies include intermittent (IHD), diffusive (HD), hybrid therapies (PIRRT, IHDF), convective (HF), and continuous (CVVHF, continuous hemofiltration)
• IHD (Intermittent Hemodialysis) involves short treatment sessions with discontinuous dialysis
• HD (Hemodialysis) is based on diffusion across a semipermeable membrane, removing low molecular weight solutes (500-1000 Da)
• HF (Hemofiltration) uses convective removal of larger molecules (10,000-50,000 Da) across a semipermeable membrane
• Hybrid therapies (PIRRT and IHDF) combine intermittent and continuous techniques, adding diffusive clearance with intermittent treatments

Hybrid Therapies: Different Names

• Multiple terms describe hybrid therapies, including sustained low-efficiency dialysis (SLED), slow low-efficiency extended daily dialysis (SLEDD), prolonged intermittent daily renal replacement therapy (PIRRT), extended dialysis (ED), extended daily dialysis (EDD), extended daily dialysis with filtration (EDDf), go-slow dialysis, and accelerated veno-venous hemofiltration (AVVH)

Blood Purification Techniques (Specific)

• SCUF (single-pass continuous ultrafiltration): blood flow - single pass through a filter
• CVVH (continuous venovenous hemofiltration): blood flow through a filter continuously
• CVVHDF (continuous venovenous hemofiltration with added diffusive clearance): blood flow through a filter continuously with diffusive clearance
• TPE (Therapeutic Plasma Exchange): plasma removed, replaced, and put back in.
• CPFA (Continuous Plasma Filtration and Adsorption): removes solutes/toxins with adsorbents.
• HVHF (High-volume venovenous hemofiltration): high volume replacement/clears greater amounts of solute
• Methods like SCUF, CVVH, CVVHDF, TPE, CPFA, HVHF, and HDF work with varying blood and dialysate flows and filter types to target different molecular weights and patient needs.

Hemodiafiltration (HDF)

• HDF combines diffusive and convective removal of solutes across a semipermeable membrane
• Low molecular weight solutes are removed primarily through diffusion while larger molecules are removed through convection
• Examples of substances removed during HDF include urea, and IL6

Why Use Hybrid Therapies?

• Advantages of hybrid therapies include improved small solute removal (especially in post-acute settings), increased convenience especially after the first few days, improved hospital/ICU workflow, and decreased therapy side effects, such as anticoagulation

Blood Flow and Dialysate Flow in HD and CRRT

• Qb (blood flow) and Qd (dialysate flow) are critical factors in hemodialysis (HD) and continuous renal replacement therapy (CRRT)
• Qb:Qd ratios are tailored to optimize solute clearance and patient-specific needs
• In HD, Qd is typically in excess of or higher than Qb to allow for proper solute exchange while in contrast in CRRT Qb is typically in excess of or higher than Qd but may vary in use

Choice of Modality

• Factors influencing treatment modality include patient characteristics (e.g., size, condition, goals) and treatment goals (e.g., needed fluid removal and URR)
• The choice depends on the specific needs of the patient, treatment goals and calculated flow rates of both blood (Qb) and dialysate (Qd) flows to ensure proper treatment

What Can We Expect From Treatment?

• Patient size, renal function, and volume of treatment are considered to determine expected outcomes
• Expected results may depend on the specific type of treatment being used and calculated clearance and expected URR (Urea Reduction Rate) and treatment duration (Td)

HDF: Hemofiltration, (pre and post)

• In HF, (pre and post) different filtration volumes are calculated to ensure effective treatment for the patient
• These volume and flow rates are calculated depending on the needs for the patient including patient size to determine the correct treatment

Online-HDF and Water Quality

• Online HDF requires specific water quality, such as <200 cfu/ml, <0.5 endotoxin unit/ml, for USA and <100 cfu/ml for Europe, and Ultrapure solution / water: <0.1 cfu/ml for optimal results

HDF Systems

• HDF can involve various systems including online HDF (high volume HDF), internal HDF, and expanded dialysis HDx
• Biofiltration often uses lower volumes of HDF with compartmental blood purification, typically with bicarbonate in the replacement fluid rather than the dialysate
• Double chamber HDF and mid-dilution HDF are also possible considerations

Clinical and Laboratory Evidence related to HDF

• HDF (including Online and Internal HDF) has demonstrated benefits in human patients, including increased solute removal and improvements in some kidney parameters and inflammation parameters
• These methods are shown to reduce complications like hypotension, or improved treatment in cases of Acute Kidney Injury (AKI) and Sepsis

This quiz focuses on the benefits of convective clearance in intermittent hemodialysis (IHD), including its impact on coagulation factors and the classification of middle molecules. Participants will match specific middle molecules with their details to enhance understanding of their roles in therapies.