Synopsis
Identify anaemia and fatigue mechanisms without missing bleeding, sepsis, haemolysis or cardiopulmonary danger, correct reversible deficiencies and use red-cell transfusion, iron, erythropoiesis stimulation, rehabilitation and symptom support according to physiology, treatment intent and patient goals.
- Fatigue in cancer is not synonymous with anaemia; assess bleeding, sepsis, thrombosis, heart and lung disease, endocrine toxicity, sleep, pain, mood, medicines and deconditioning.
- First-line anaemia tests are FBC with indices, reticulocyte count and blood film, compared with baseline and treatment cycle to classify production failure, loss or destruction.
- Iron studies require ferritin, transferrin saturation and inflammation context because cancer-associated hepcidin can produce low usable iron despite a normal or high ferritin.
- Add B12, folate, renal, liver, thyroid, haemolysis, bleeding and marrow investigations according to indices, reticulocytes, film and clinical pattern.
- Treat the cause: control bleeding, infection and cancer; replace iron, B12 or folate; manage renal or endocrine disease; modify marrow-toxic treatment when appropriate.
- Transfusion decisions use symptoms, haemodynamic stability, rate of fall, bleeding, comorbidity, treatment intent and patient goals rather than a haemoglobin number alone.
- For stable adults without major haemorrhage, acute coronary syndrome or regular transfusion needs, NICE supports a restrictive threshold around 70 g/L and a post-transfusion target of 70 to 90 g/L.
- Give one red-cell unit at a time in a stable non-bleeding adult, then reassess symptoms and haemoglobin before prescribing another unit.
- Use slower infusion, careful fluid balance and selected diuretic support for high circulatory-overload risk; a diuretic does not make unnecessary transfusion safe.
- Check historical antibodies, special requirements and previous reactions before sampling; some haematology, transplant and purine-analogue exposures require irradiated components.
- During transfusion, verify identity at the bedside and observe baseline, early and completion vital signs according to policy; stop immediately for a suspected reaction.
- Intravenous iron is preferred when absolute or functional deficiency needs rapid correction and oral absorption or inflammatory blockade makes tablets ineffective, but exclude active infection and monitor hypersensitivity.
- Erythropoiesis-stimulating agents may reduce transfusion in selected adults receiving chemotherapy under NICE eligibility; use the lowest effective haemoglobin goal and review thrombosis and iron availability.
- For persistent cancer-related fatigue, graded aerobic and resistance exercise is first-line when safe, combined with sleep, pain, mood, nutrition and energy-conservation support.
Key red flags
Tachycardia, hypotension, syncope, melaena, haematemesis, brisk vaginal bleeding or expanding tumour haemorrhage requires urgent source control and major-bleeding assessment.
Chest pain, ischaemic ECG change, heart failure, resting breathlessness or hypoxia with anaemia lowers tolerance and requires urgent senior transfusion and cardiac review.
Fever, rigors, confusion or hypotension after systemic anticancer treatment is possible neutropenic sepsis even when fatigue and anaemia appear to explain weakness.
Sudden fatigue with jaundice, dark urine, back pain, rising bilirubin or falling haptoglobin suggests haemolysis and requires urgent cause and transfusion investigation.
New dyspnoea, pleuritic pain, unilateral leg swelling or disproportionate tachycardia requires cancer-associated-thrombosis assessment rather than attribution to anaemia alone.
Fever, chills, dyspnoea, wheeze, pain, hypotension, rash or dark urine during transfusion requires immediate cessation and reaction protocol.
Rapid haemoglobin fall, pancytopenia, leukoerythroblastic film or neurological bleeding suggests marrow failure, DIC, TMA or occult haemorrhage needing urgent specialist review.
Investigation priorities
Classify anaemia by cell size, marrow response and morphological evidence of blood loss, haemolysis, dysplasia or infiltration.
Management branches
Haemoglobin falls or fatigue and breathlessness worsen during cancer care.
- Assess ABCDE danger, bleeding, infection, thrombosis, cardiopulmonary symptoms, treatment timing, nutrition, endocrine features, sleep, mood and current medicines.
- Obtain FBC, reticulocytes and film, iron studies and selected renal, vitamin, thyroid, haemolysis and bleeding tests, escalating unusual multilineage patterns to haematology.
- Treat reversible causes and agree whether the immediate goal is physiological rescue, treatment completion, symptom improvement or longer-term transfusion avoidance.
A non-bleeding adult has symptomatic anaemia or falls below the appropriate restrictive threshold.
- Review symptoms, rate of fall, heart and lung reserve, fluid risk, previous reactions, antibodies, special requirements, alternatives and patient goals and obtain valid consent.
- Prescribe one compatible red-cell unit at a rate matched to circulatory risk, with identity checks and baseline and early observations and an explicit reaction plan.
- Reassess symptoms, observations and haemoglobin before any further unit and document whether benefit justifies future transfusion or cause-directed treatment should replace it.