An adult who is short of breath
Difficulty in breathing can come from the airway, the lungs, the heart or the blood. With a careful ABCDE, a focused history and two finger-prick tests you can usually tell which, and that decides what you do in the next hour.
- Setting: Health centre with oxygen concentrator, 2 hours by road from the district hospital
- For clinical officers, nurses and doctors at first-level facilities
- Reviewed October 2026
The presentation
Grace, 36, has been increasingly short of breath for 2 weeks. Today she was breathless walking the short way from the bus. She gave birth to her fourth child 7 weeks ago. Her sister carries the baby.
| Vital sign | Value |
|---|---|
| Breathing rate | 28 per minute |
| Pulse | 122 per minute, regular |
| Blood pressure | 104/64 mmHg |
| Temperature | 37.2 °C |
| SpO2 | 93% on air |
| Conscious level (AVPU) | Alert |
Tests at hand: Haemoglobin (Hb) · Blood glucose (finger-prick) · Malaria rapid diagnostic test (RDT) · Urine dipstick · Pulse oximetry (SpO2) · HIV rapid test
- Severe anaemia Must not missStill possible
- Heart failure (including peripartum cardiomyopathy) Must not missStill possible
- Pulmonary embolism Must not missStill possible
- PneumoniaStill possible
- AsthmaStill possible
- TB with pleural or pericardial effusionStill possible
- Diabetic ketoacidosisStill possible
- Malaria with anaemiaStill possible
Work through it
Read each question and decide your own answer first. Then open the model answer and see how the differential changes.
- Step 1 of 6 · Look
Start with ABCDE. What do you check, what do you find, and does Grace need anything done straight away?
Model answer
- A
- Talking in short sentences; no stridor, no swelling of lips or tongue. Airway open.
- B
- Rate 28, SpO2 93%, using neck muscles a little. Equal breath sounds, fine crackles at both bases, no wheeze.
- C
- Pulse 122, BP 104/64, hands cool, capillary refill 2 seconds. Very pale inner eyelids.
- D
- Alert. Check glucose.
- E
- Both ankles swollen; no rash, no bites, no injury.
She has no airway problem and is not in shock, but she is working hard to breathe. Sit her upright, give oxygen if SpO2 falls below 92% or she tires, put in an IV cannula but do not run fluids fast, and keep checking her. Severe pallor and difficulty in breathing make her a priority patient: she is seen now, not in the queue.
Differential now- Severe anaemia Must not missLeading (moved up)
- Heart failure (including peripartum cardiomyopathy) Must not missLeading (moved up)
- Pulmonary embolism Must not missStill possible
- PneumoniaStill possible
- TB with pleural or pericardial effusionStill possible
- Malaria with anaemiaStill possible
- AsthmaLess likely (moved down)
- Diabetic ketoacidosisLess likely (moved down)
- Step 2 of 6 · Ask
Now the SAMPLE history. Which questions separate the causes?
Model answer
- Onset: sudden (clot, pneumothorax, heart attack) or over days to weeks (anaemia, heart failure, effusion, infection)?
- Worse lying flat, or waking breathless at night (fluid on the lungs)? Swelling of both legs?
- Chest pain worse on breathing in, or pain and swelling of one leg (pulmonary embolism)?
- Fever, cough, sputum, night sweats, weight loss (pneumonia, TB)?
- Bleeding: at the birth, heavy periods since, black stools; diet; previous anaemia; malaria.
- Past history: asthma, heart or kidney disease, rheumatic fever, diabetes, HIV, TB.
- Medicines, and whether she took iron in pregnancy.
Grace bled heavily after the birth and was told she was 'low in blood' but went home the next day. She did not finish her iron tablets. She now needs two pillows to sleep and wakes breathless. Her ankles have swollen over a week. No chest pain, no calf pain, no fever, no cough. No known heart disease, asthma or diabetes. HIV negative in pregnancy.
Differential now- Severe anaemia Must not missLeading
- Heart failure (including peripartum cardiomyopathy) Must not missLeading
- Malaria with anaemiaStill possible
- Pulmonary embolism Must not missLess likely (moved down)
- PneumoniaLess likely (moved down)
- TB with pleural or pericardial effusionLess likely (moved down)
- Diabetic ketoacidosisLess likely
- AsthmaSet aside for now (moved down)
- Step 3 of 6 · Look
On the secondary examination, what do you look and listen for to decide whether this is the heart, the lungs or the blood?
Model answer
- Neck veins: raised in heart failure (and in tension pneumothorax or tamponade).
- Heart: a murmur (valve disease, or a flow murmur in severe anaemia), extra sounds, muffled sounds.
- Lungs: crackles at both bases (fluid), dullness at one base (effusion), wheeze.
- Abdomen: enlarged tender liver, ascites.
- Legs: both swollen (heart failure) or one swollen and tender (clot).
Neck veins are raised. There is a soft murmur over the heart. Fine crackles at both bases. Liver edge 2 cm below the ribs, tender. Both ankles swollen equally; calves soft and not tender.
Differential now- Severe anaemia Must not missLeading
- Heart failure (including peripartum cardiomyopathy) Must not missLeading
- Malaria with anaemiaStill possible
- PneumoniaLess likely
- Diabetic ketoacidosisLess likely
- Pulmonary embolism Must not missSet aside for now (moved down)
- AsthmaSet aside for now
- TB with pleural or pericardial effusionSet aside for now (moved down)
- Step 4 of 6 · Test
You can do haemoglobin, glucose, a malaria RDT and a urine dipstick. What do you expect each to tell you?
Model answer
- Haemoglobin: confirms severe anaemia, which can itself cause heart failure. In non-pregnant adults, below 8 g/dL is severe anaemia.
- Glucose and urine dipstick (glucose, ketones): rule out diabetic ketoacidosis as a cause of fast breathing. The dipstick also checks protein: pre-eclampsia can still appear in the weeks after birth.
- Malaria RDT: malaria is a common cause of anaemia where it is transmitted.
Results: Hb 5.9 g/dL. Glucose 5.0 mmol/L. Urine: no glucose, no ketones, no protein. RDT negative.
Differential now- Severe anaemia Must not missLeading
- Heart failure (including peripartum cardiomyopathy) Must not missLeading
- PneumoniaLess likely
- Pulmonary embolism Must not missSet aside for now
- AsthmaSet aside for now
- TB with pleural or pericardial effusionSet aside for now
- Diabetic ketoacidosisSet aside for now (moved down)
- Malaria with anaemiaSet aside for now (moved down)
- Step 5 of 6 · Do
Put it together. What is the working diagnosis, and what can and cannot be done here?
Model answer
Very severe anaemia (Hb 5.9 g/dL), most likely from blood loss at delivery without iron replacement, with signs of heart failure: raised neck veins, crackles, enlarged liver and swollen ankles. Heart failure starting in the months after birth could also be peripartum cardiomyopathy, which needs hospital assessment of the heart.
She needs blood transfusion and a heart assessment, neither of which the health centre can provide. This is an urgent referral.
- Keep her sitting up. Oxygen if SpO2 is below 92% or she worsens.
- Do not give fast IV fluids: in chronic severe anaemia they can tip her into pulmonary oedema. If fluids are needed, give them slowly and listen for crackles often.
- Do not start oral iron and send her home; iron cannot raise the haemoglobin fast enough.
Differential now- Severe anaemia Must not missLeading
- Heart failure (including peripartum cardiomyopathy) Must not missLeading
- Pulmonary embolism Must not missSet aside for now
- PneumoniaSet aside for now (moved down)
- AsthmaSet aside for now
- TB with pleural or pericardial effusionSet aside for now
- Diabetic ketoacidosisSet aside for now
- Malaria with anaemiaSet aside for now
- Step 6 of 6 · Do
How do you organise a safe transfer, and what about the baby?
Model answer
- Call ahead so the hospital can arrange blood.
- Transfer sitting up, with oxygen on the way if available, and a health worker or a well-briefed relative.
- Write a handover: ABCDE findings, Hb, the times of any treatment, and the history of postpartum haemorrhage.
- The baby goes with her. Breastfeeding continues.
- Ask about her mood and support at home: severe illness after birth is a risk for depression.
Your blood is very low and your heart is working too hard. You need a blood transfusion in hospital today. Take the baby with you and keep feeding him.
Must-not-miss conditions
| Condition | Clues | What to do at first-level care |
|---|---|---|
| Severe anaemia with heart failure | Severe pallor, fast pulse, breathless, raised neck veins, crackles, swollen legs; Hb below 8 g/dL (and especially below 7 g/dL). | Sit up, oxygen if low, no fast IV fluids; urgent referral for transfusion. |
| Peripartum cardiomyopathy | Heart failure in the last month of pregnancy or within 6 months of birth. | Urgent referral for heart assessment; it is a cause of maternal death. |
| Pulmonary embolism | Sudden breathlessness, pleuritic chest pain, one painful swollen leg; pregnancy and the weeks after birth raise the risk. | Oxygen; urgent referral. |
| Tension pneumothorax | Breathless with low BP, absent breath sounds on one side, raised neck veins, trachea pushed aside. | Needle decompression, then urgent transfer. |
| Severe allergic reaction | Swelling of lips and tongue, stridor or wheeze, hives, after a trigger. | IM adrenaline at once, oxygen, monitor; transfer. |
| Diabetic ketoacidosis | Deep fast breathing, high glucose, ketones in the urine, dehydration. | IV fluids and urgent transfer. |
Decision at first-level care
Grace has very severe anaemia (Hb 5.9 g/dL) with signs of heart failure 7 weeks after a postpartum haemorrhage; peripartum cardiomyopathy also needs to be excluded. She needs transfusion and cardiac assessment in hospital. Stabilise (upright, oxygen if needed, no fast fluids) and refer urgently, with the baby.
Source: WHO and ICRC Basic emergency care (2018); WHO recommendations on maternal and newborn care for a positive postnatal experience (2022).
- Asthma or COPD flare-up responding to salbutamol (and prednisolone) within the hour, SpO2 normal, able to walk.
- Mild to moderate anaemia without breathlessness at rest: treat the cause, oral iron, review.
- Breathlessness settling after treatment: watch for 1 to 3 hours (salbutamol lasts about 3 hours) before deciding.
- Possible anxiety-related breathing, only after serious causes are excluded and the vital signs are normal.
- Breathless at rest, SpO2 below 92%, or any red triage sign.
- Severe anaemia with breathlessness or heart failure (for transfusion).
- Suspected heart failure, peripartum cardiomyopathy, pulmonary embolism, effusion or pneumothorax.
- Diabetic ketoacidosis, or wheeze not responding to treatment.
- Any woman in pregnancy or the 6 weeks after birth with fast or difficult breathing.
Key learning points
- ABCDE first, fixing problems as you find them; then SAMPLE history; then the secondary examination.
- Sort difficulty in breathing by area: airway, lungs, heart, or the whole body (anaemia, ketoacidosis, poisoning).
- Breathlessness in the weeks after birth is a maternal danger sign: think anaemia, peripartum cardiomyopathy and pulmonary embolism.
- In chronic severe anaemia, IV fluids are given slowly if at all; the treatment is transfusion in hospital.
- Two finger-prick tests (Hb and glucose) and a dipstick separate several causes in minutes.
Sources
- World Health Organization and International Committee of the Red Cross. Basic emergency care: approach to the acutely ill and injured. Participant workbook. 2018 (ISBN 9789241513081). Module 3, approach to difficulty in breathing: ABCDE key elements, SAMPLE history, secondary examination, key airway, lung, heart and systemic causes, management including chronic severe anaemia, disposition.
- World Health Organization, International Committee of the Red Cross and Médecins Sans Frontières. Interagency Integrated Triage Tool (age 12 and over). 2023. Red and yellow criteria; up-triage vital signs (SpO2 below 92%).
- World Health Organization. WHO recommendations on maternal and newborn care for a positive postnatal experience. 2022. Maternal danger signs after birth, including fast or difficult breathing.
- World Health Organization. Guideline on haemoglobin cutoffs to define anaemia in individuals and populations. 2024. Severe anaemia in non-pregnant adults: haemoglobin below 8 g/dL.
- World Health Organization. IMAI district clinician manual: hospital care for adolescents and adults, volume 1. 2011. Heart failure signs; peripartum cardiomyopathy timing (as used in the heart failure protocol).