治療性血球分離術

Buzzwords → Dx

Workup before procedure

• Calculated plasma volume (typically 1.0–1.5 PV exchanged per session for TPE).
• Vascular access (large-bore central line typically; peripheral IV/access in stable pts).
• Replacement fluid choice (FFP for TTP, albumin for most others).
• Calcium replacement (citrate anticoagulant chelates Ca → hypocalcemia).
• Complete coagulation panel + CBC baseline + serial.

Algorithm — TPE workflow

flowchart TD
  A[Indication for TPE] --> B[ASFA category I-II?<br>established benefit?]
  B -- yes --> C[Establish access<br>large-bore central line]
  C --> D[Calculate plasma volume<br>1-1.5 PV per session]
  D --> E{Replacement fluid?}
  E -- TTP --> F[FFP all volume<br>1 PV exchange]
  E -- AIHA / GBS / etc --> G[Albumin 5%<br>± FFP for severe coagulopathy]
  D --> H[Citrate anticoagulant<br>monitor + supplement Ca]
  H --> I[Daily for TTP<br>q1-2 days for others<br>continue per response]
  I --> J[Monitor CBC, electrolytes, Ca<br>plt, LDH for TTP]
  J -- response --> K[Taper q2 days then stop<br>TTP: continue caplacizumab]
  J -- inadequate --> L[Continue + add immunosuppression / rituximab]

Pearls / Pitfalls

• TPE in TTP uses FFP replacement (replenishes ADAMTS13). Cryosupernatant alternative (lacks ULvWF). Albumin is INADEQUATE — does not replace ADAMTS13.
• Citrate-induced hypocalcemia — perioral tingling, paresthesias, tetany; treat with calcium gluconate IV during procedure.
• Hypotension during apheresis — common (volume shifts, vasovagal); slow rate, IVF.
• Filter clotting / line-related complications — heparin alternative anticoagulation if HIT or active bleeding.
• Allergic reactions to FFP — pre-medicate with diphenhydramine; severe → switch to albumin where possible.
• Drug removal during TPE — many drugs are removed; redose meds (esp. recent anticoagulants, DOACs) post-TPE.
• Erythrocytapheresis (RBC exchange) for SCD: target HbS <30 % for ACS / stroke / pre-op. Less iron loading than simple transfusion.
• Leukapheresis in AML / ALL with WBC >100K: bridge to chemotherapy in symptomatic leukostasis. Doesn't replace cytoreduction.
• Stem cell mobilization / collection: G-CSF for autologous; G-CSF + plerixafor for hard-to-mobilize (lymphoma, MM); allogeneic donor mobilized similarly.
• Pulmonary alveolar proteinosis (whole-lung lavage): separate procedure; not standard apheresis.
• Apheresis in ICU: monitor for hemodynamic + electrolyte changes carefully; coordinate with critical care.

Cross-references

• TTP — TPE essential
• Waldenström — hyperviscosity
• Hyperviscosity / Leukostasis
• SCD — RBC exchange
• Stem cell mobilization for ASCT
• Plasma products

相關題目

• Q-169 — TPE in TTP — replacement fluid choice
• Q-170 — SCD — RBC exchange (erythrocytapheresis)
• Q-171 — Leukapheresis indication

Sources