Patient Body Parameters Live
Calculates Total Blood Volume (TBV), Total Plasma Volume (TPV), and Red Cell Volume (RCV). Results carry forward automatically to all other calculators.
Nadler's Formula for Total Blood Volume (TBV)
H = Height in meters · W = Weight in kg · Nadler's formula is the standard used by Spectra Optia® and Haemonetics® MCS+
📖 Nadler et al., Surgery 1962 · Lemmens et al., Obes Surg 2006📊 Patient Parameters
| Parameter | Average Adult Male | Average Adult Female | Clinical Significance |
|---|---|---|---|
| TBV | 5,000–6,000 mL | 4,000–5,000 mL | Basis for all apheresis volume calculations |
| TPV | 2,700–3,200 mL | 2,300–2,800 mL | Determines TPE prescription volume |
| RCV | 2,200–2,800 mL | 1,600–2,200 mL | Determines RBC exchange donor volume |
| Hematocrit | 40–52% | 36–48% | Key variable; changes during procedure |
Therapeutic Plasma Exchange (TPE) Live
Calculates plasma volume to process, replacement fluid volumes, and estimated solute reduction per session. ASFA recommends 1.0–1.5× plasma volumes per session for most indications.
TPE Volume & Solute Removal
Assumes single-compartment model, intravascular distribution, and isovolumetric exchange. Valid for IgG, IgM, fibrinogen, and other high-MW substances.
📖 ASFA 9th Edition (2023) · Cervantes et al., AJKD 2023 · Reverberi, Blood Transfus 2007Auto-fill: If you calculated Patient Body Parameters first, the TPV field below is pre-filled. Otherwise, enter TPV manually.
📊 TPE Prescription
| Replacement Fluid | Standard Use | Preferred When | Avoid When |
|---|---|---|---|
| 5% Albumin | First-line for most indications | Routine TPE, maintenance sessions | Active bleeding, coagulopathy, TTP (use FFP) |
| Fresh Frozen Plasma (FFP) | TTP (mandatory), anti-GBM, HUS | Coagulopathy, factor replacement needed | Routine use (risk of allergic reactions, TRALI) |
| 50% Albumin / 50% FFP | Compromise approach | Mild coagulopathy, last few sessions | Active TTP (use 100% FFP) |
| Normal Saline | Partial replacement only | Mild hyperviscosity, volume management | Full-volume replacement (hypoproteinemia risk) |
Solute Removal Kinetics
Models the exponential removal of intravascular substances during TPE. Useful for understanding how many sessions are needed to achieve a target reduction level.
One-Compartment Removal Model
Valid for high-molecular-weight substances (IgG, IgM, fibrinogen, LDL) that are predominantly intravascular.
📖 Reverberi & Reverberi, Blood Transfus 2007 · Wiener & Wexler 1946📊 Predicted Removal by Session
| Session | Volume Exchanged | Residual (%) | Estimated Level | % Removed (Cumulative) |
|---|
RBC Exchange — Procedure Setup Live
Calculates Fraction of Cells Remaining (FCR) and the Replaced: Exchange volume for automated RBC exchange. Enter patient data, select exchange type, set fluid and run targets — FCR auto-calculates from HbS% values.
RBC Exchange Core Formulas
H = Height in meters · W = Weight in kg · Hct values as decimals · FCR = Fraction of Cells Remaining
📖 Nadler et al., Surgery 1962 · ASFA 9th Edition · Terumo BCT™ RBCX ProtocolPatient Data
Fluid Data
Run Targets
📊 RBC Exchange — Procedure Setup Results
RBC Exchange (RBCX) — Sickle Cell Disease Live
Calculates Fraction of Cells Remaining (FCR) and donor pRBC volume needed to achieve a target post-procedure HbS%. Supports Exchange Only and Depletion/Exchange protocols.
Core Formulas — Automated RBC Exchange
FCR ≠ HbS% — Key Distinction
FCR (Fraction of Cells Remaining) is the % of the patient's original RBC volume remaining after the procedure. HbS% is the % of sickled hemoglobin. FCR = HbS% only if the patient's starting HbS is 100%. For transfused patients, always calculate FCR from HbS% using the formula above.
Exchange Only: Direct replacement of patient RBCs with donor RBCs. Most common. | Depletion/Exchange: Depletes patient RBCs first, then exchanges. Requires fewer donor units. Recommended when pre-Hct ≥26%.
🔴 RBC Exchange Results
Leukocytapheresis — WBC Reduction
Estimates post-procedure WBC count and sessions needed to reach a target WBC level. Typically indicated for symptomatic hyperleukocytosis (WBC >100×10⁹/L).
WBC Reduction Estimate
Emergency Threshold: Leukapheresis is typically indicated when WBC >100×10⁹/L with symptomatic leukostasis. In AML, consider at WBC >50×10⁹/L with symptoms. This is a temporizing measure — cytoreductive chemotherapy must follow.
📊 Leukocytapheresis Estimates
HPC Stem Cell Collection (Leukapheresis)
Predicts CD34+ cell yield from peripheral blood leukapheresis. Used to plan collection sessions and determine if target dose will be achieved.
CD34+ Yield Prediction
📊 HPC Collection Prediction
| PB CD34+ Count | Mobilization Status | Expected Yield | Clinical Action |
|---|---|---|---|
| <5 cells/µL | Poor mobilization | Unlikely to meet minimum dose | Consider plerixafor rescue, delay collection |
| 5–10 cells/µL | Marginal | May require multiple sessions | Proceed with caution; consider plerixafor |
| 10–20 cells/µL | Adequate | Likely to meet minimum (2×10⁶/kg) | Proceed with collection |
| >20 cells/µL | Good mobilization | Likely to meet optimal (4×10⁶/kg) | Proceed; single session may suffice |
Platelet Collection Efficiency (CE)
Calculates CE1 and CE2 for plateletpheresis and estimates the therapeutic dose. Used for donor qualification, device performance monitoring, and quality control.
Collection Efficiency Formulas
📊 Plateletpheresis Results
Citrate Toxicity Risk Assessment Live
Calculates citrate infusion rate and assesses hypocalcemia risk based on blood flow rate, ACD-A ratio, and patient weight.
Citrate Infusion Rate
High-Risk Patients: Liver disease, hypoalbuminemia, hypomagnesemia, alkalosis, pediatric patients, and patients on calcium channel blockers are at elevated risk. Consider prophylactic calcium supplementation.
📊 Citrate Toxicity Assessment
| Severity | Symptoms | iCa²⁺ Level | Management |
|---|---|---|---|
| Mild | Perioral tingling, paresthesias, chills | 0.9–1.1 mmol/L | Slow blood flow rate, oral calcium carbonate |
| Moderate | Muscle cramps, nausea, anxiety, tremors | 0.7–0.9 mmol/L | Reduce flow rate, IV calcium gluconate 1–2 g |
| Severe | Tetany, carpopedal spasm, arrhythmia, hypotension | <0.7 mmol/L | Stop procedure, IV calcium gluconate 2–4 g, ECG monitoring |
LDL Apheresis Efficacy Live
Calculates acute LDL reduction per session and time-averaged LDL using the Kroon formula. Estimates treatment frequency needed to achieve target LDL levels.
LDL Reduction & Kroon Formula
📊 LDL Apheresis Efficacy
| Patient Type | LDL Threshold | Additional Criteria | ASFA Category |
|---|---|---|---|
| HoFH — No CVD | LDL ≥300 mg/dL | Max tolerated drug therapy | Cat I, Grade 1B |
| HoFH — With CVD | LDL ≥200 mg/dL | Max tolerated drug therapy | Cat I, Grade 1B |
| HeFH — With CVD | LDL ≥160 mg/dL | Failure of drug therapy | Cat II, Grade 1B |
| Elevated Lp(a) — With CVD | Lp(a) ≥60 mg/dL | Progressive CVD despite LDL control | Cat II, Grade 2C |
Replacement Fluid Calculator (TPE)
Calculates albumin and FFP volumes required for a TPE procedure, estimates coagulation factor depletion with albumin-only replacement, and determines FFP unit requirements.
Replacement Fluid Formulas
💧 Replacement Fluid Prescription
| Indication | Preferred Fluid | Rationale | ASFA Guidance |
|---|---|---|---|
| TTP (ADAMTS13 deficiency) | 100% FFP or cryopoor plasma | Replenishes ADAMTS13 | Cat I, Grade 1A |
| HUS (Shiga toxin) | FFP or albumin | Less clear benefit; albumin acceptable if no coagulopathy | Cat III, Grade 2C |
| ANCA-AAV / Anti-GBM | 5% Albumin | No coagulation factor replacement needed | Cat I–II |
| Myasthenia Gravis / CIDP | 5% Albumin | Standard; FFP only if coagulopathy present | Cat I, Grade 1B |
| Coagulopathy / Pre-surgical | 50–100% FFP | Maintain coagulation factors ≥40% activity | Institutional protocol |
Immunoadsorption (IA) — IgG Removal
Calculates IgG removal per session and cumulative removal across multiple sessions using Protein A or other immunoadsorption columns.
Immunoadsorption IgG Removal
🔬 Immunoadsorption Results
| Indication | Target Molecule | Column Type | ASFA Category |
|---|---|---|---|
| Myasthenia Gravis (severe) | Anti-AChR / Anti-MuSK IgG | Protein A or tryptophan | Cat I, Grade 1C |
| ANCA-AAV (refractory) | ANCA (IgG) | Protein A | Cat II, Grade 2C |
| Dilated Cardiomyopathy | Anti-β1-AR IgG | Protein A | Cat II, Grade 1B |
| Pemphigus Vulgaris | Anti-Dsg1/3 IgG | Protein A or IA | Cat II, Grade 1C |
| Hemophilia A (inhibitors) | Anti-FVIII IgG | Protein A | Cat II, Grade 2C |
Double Filtration Plasmapheresis (DFPP)
Calculates sieving coefficient, removal ratio, and discard volume for DFPP. Selectively removes large-MW proteins (IgG, IgM, fibrinogen) while retaining albumin.
DFPP Sieving & Removal Formulas
🔁 DFPP Sieving Results
Extracorporeal Volume (ECV) Safety Check Live
Determines whether circuit priming is required based on the extracorporeal volume as a percentage of the patient's total blood volume. Critical for pediatric and small-volume patients.
ECV Safety Threshold
In pediatric patients, pRBC prime is mandatory when ECV >15% TBV. In adults, 5% albumin or NS is acceptable.
📖 Schwartz et al., J Clin Apheresis 2016 · ASFA Pediatric Apheresis Guidelines🛡️ ECV Safety Assessment
Extracorporeal Photopheresis (ECP)
Calculates Uvadex® (8-MOP) dose, treatment volume, and eligibility check for ECP procedures. Supports both inline (Therakos® CELLEX®) and offline (Spectra Optia cMNC) methods.
Uvadex Dosing Formula (FDA-Approved)
Uvadex = 20 mcg/mL methoxsalen. The 0.017 factor is the FDA-approved dosing constant for the CELLEX system. Minimum eligibility: Hgb >10 g/dL, PLT >20×10⁹/L, weight ≥20 kg (inline).
📖 Therakos CELLEX PI · FDA Label for Uvadex · ASFA 9th Edition Cat I (CTCL), Cat II (GvHD)☀️ ECP Prescription Results
| Indication | ASFA Category | Grade | Notes |
|---|---|---|---|
| CTCL (Erythrodermic MF/SS) | I | 1B | First-line for erythrodermic stage |
| Acute GvHD (steroid-refractory) | II | 2C | Second-line; used with steroids |
| Chronic GvHD | I | 1B | Well-established; skin, liver, lung |
| Cardiac Transplant Rejection | II | 1B | Prophylaxis and rejection treatment |
| Lung Transplant — BOS | II | 1C | Bronchiolitis obliterans syndrome |