# Post-CPB Bleeding Care

> Post-CPB bleeding care for Perfusion Technology: surgical versus coagulopathic causes, TEG ROTEM algorithm, protamine check, fibrinogen targets and products.

- Canonical URL: https://prepelephant.com/topics/allied/perfusion-technology/post-cpb-care-bleeding
- Exam / course: Allied Health · Subject: Perfusion Technology
- Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team
- First published: 2026-10-02
- Last updated: 2026-10-02
- How to cite: "Post-CPB Bleeding Care", PrepElephant, https://prepelephant.com/topics/allied/perfusion-technology/post-cpb-care-bleeding

## Direct answer

A technically perfect operation can still end in a coagulopathic ooze, and the first triage is surgical versus non-surgical: localised, pulsatile or torrential bleeding points toward a surgical source, while diffuse ooze from raw surfaces, venous lines and the donor site points toward the bypass-induced coagulopathy of platelet dysfunction, hypofibrinogenaemia, residual heparin, dilution, hypothermia and hyperfibrinolysis. Management runs on correction and measurement together — warmth above 36 degrees, ionised calcium normal, residual heparin reversed and checked, then viscoelastic testing (TEG or ROTEM with a heparinase comparison) steering products: protamine for heparin effect, cryoprecipitate or fibrinogen concentrate when fibrinogen sits below about 1.5-2 g/L, platelets for a low MA/MCF, tranexamic acid for lysis. Persistent high-volume bleeding after correction is re-exploration, not more plasma.

## What you must remember

- **Bypass hits platelets hardest:** numbers fall and remaining platelets are dysfunctional from activation and hypothermia — platelet therapy is functional, judged by viscoelastic tests, not just counts.
- **Residual heparin first:** ACT or, better, a heparinase TEG/ROTEM comparison — if the heparinase channel clots better than the plain channel, residual heparin is still contributing; protamine in 25-50 mg steps, guided, because overdose is itself anticoagulant and antiplatelet.
- **Fibrinogen is the first factor to fall:** target above roughly 1.5-2 g/L in the bleeding patient; cryoprecipitate (fibrinogen-rich) or fibrinogen concentrate where available.
- **Viscoelastic algorithm:** prolonged CT/R or EXTEM CT — heparin or factor deficiency (protamine or plasma); low MA/MCF — platelets; low FIBTEM — fibrinogen; lysis on the tracing — tranexamic acid.
- **The physical floor:** temperature above 36 degrees (cold platelets do not work), pH corrected, ionised calcium 1.1-1.3 mmol/L after citrate loads, haematocrit around 24-25 plus.
- **Products and autologous options:** platelets (an apheresis unit or a pooled random-donor pack), fresh frozen plasma about 10-15 mL/kg, cryoprecipitate 3-5 units per 10 kg (Indian protocol habit), tranexamic acid per policy — alongside cell salvage of shed blood and residual pump blood processed rather than returned raw.
- **Re-exploration threshold:** continued bleeding at roughly 300-400 mL in the first hour (centre-defined) despite correction warrants surgical re-exploration — tamponade physiology kills quietly.
- **Antifibrinolytic context:** tranexamic acid is widely used; aprotinin, where available again, is selected for high-risk redo and complex cases per programme policy.

## One hour after the cross-clamp, worked through

The field oozes; chest drain output is 350 mL in the first hour. Sequence, not guesswork. Warmth: bladder temperature 35.9, forced-air on, fluids warm. Check heparin reversal: ACT 145 against a baseline of 105 — but the heparinase TEG shows the heparinase channel reaching clot strength minutes earlier than the plain channel, so 25 mg protamine is given in steps. ROTEM follow-up: EXTEM CT now normal, FIBTEM A5 low, platelet channel MCF low — fibrinogen 1.3 g/L. Give cryoprecipitate and one apheresis platelet unit; ionised calcium 0.98 is corrected with calcium chloride because transfused citrate is still arriving. Tranexamic runs as a continuation of the intraoperative infusion. Over the next 40 minutes the drains fall to 60 mL/h and the field dries; the record shows a cause-effect chain any examiner could reconstruct. Had the output stayed at 300 mL/h with normal viscoelastic values, the next sentence in the record would have been "return to theatre".

## Where the exam probes

Indian papers set "causes and management of bleeding after cardiopulmonary bypass" as a classic ten-marker, and the pass answer separates surgical from coagulopathic before listing mechanisms; the strong answer then orders therapy by measurement (viscoelastic algorithm) rather than by recipe. Viva favourites: which factor falls first (fibrinogen), why platelets dysfunction (activation, hypothermia, the pump itself), why the ACT alone misleads after protamine (its insensitivity at low heparin levels — hence heparinase channels), and the numeric re-exploration trigger your unit defends. The Indian-practice dimension is real: blood products depend on voluntary donation, random-donor platelet pools and apheresis units differ in availability by centre and by night, and examiners respect the candidate who says "fibrinogen concentrate where available, cryoprecipitate where not" — the answer of someone who has actually stood at the console.

## Frequently asked questions

### What is the first laboratory check in post-bypass bleeding?
Confirm heparin reversal — ACT with a heparinase TEG or ROTEM comparison, since ACT alone is insensitive at low heparin levels; give protamine in small guided steps.
### What fibrinogen level triggers replacement after bypass?
Below roughly 1.5-2 g/L in the bleeding patient, corrected with cryoprecipitate or fibrinogen concentrate per availability.
### Why is platelet dysfunction central to post-CPB coagulopathy?
The circuit activates and hypothermia cripples remaining platelets, so functional platelet therapy is guided by viscoelastic testing rather than count alone.
### What does a low FIBTEM value indicate and what is given?
Fibrinogen deficiency — cryoprecipitate or fibrinogen concentrate, prioritised ahead of plasma because fibrinogen falls first and furthest.
### When does postoperative bleeding mandate surgical re-exploration?
Centre-defined thresholds — commonly around 300-400 mL in the first hour despite full correction, or signs of tamponade — send the patient back to theatre.