Dyspnoea (Dyspnea)

Definition

• Harrison's Principles of Internal Medicine, 22E, p. 311

Epidemiology

• Reported in up to 50% of inpatients and 25% of ambulatory patients
• Community prevalence: 9-13%, rising to ~37% in adults ≥70 years
• Accounts for 3-4 million emergency room visits per year
• The degree of dyspnoea may predict outcomes in COPD better than FEV1, and it is formally incorporated into the GOLD COPD severity guidelines
• Post-COVID-19 syndrome has further increased its incidence
• Harrison's Principles of Internal Medicine, 22E, p. 311

Mechanisms

1. Abnormal blood gases - especially hypercapnia (CO2 excess), and to a lesser degree hypoxaemia
2. Increased work of breathing - excessive effort by respiratory muscles even when blood gases are normal
3. State of mind / psychological factors - neurogenic or emotional dyspnoea

Neural Pathways (Harrison's 22E)

Special Descriptors / Clinical Patterns

• Murray & Nadel's Textbook of Respiratory Medicine, p. (block 4)

Differential Diagnosis

Pulmonary Causes

• Airways disease: Asthma, COPD, upper airway obstruction
  • Presents with: chest tightness, wheezing, accessory muscle use
• Parenchymal disease: Interstitial lung disease (IPF, collagen vascular disease, drug/occupational pneumonitis), hypersensitivity pneumonitis, BOOP
  • Presents with: progressive exertional dyspnoea, fine crackles
• Chest wall / neuromuscular: Kyphoscoliosis, amyotrophic lateral sclerosis, myasthenia gravis, diaphragm paralysis
• Pulmonary vascular: Pulmonary hypertension, chronic thromboembolic disease (CTEPH), pulmonary embolism

Cardiac Causes

• Left heart failure (CAD, cardiomyopathy, diastolic dysfunction) - most common cardiac cause; produces raised pulmonary venous pressure
• Valvular heart disease
• Pericardial disease - constrictive pericarditis, cardiac tamponade
• Myocardial ischaemia (acute)

Other Causes

• Anaemia - reduces oxygen-carrying capacity; can cause dyspnoea at rest in severe cases
• Deconditioning - presents as "heavy breathing" or "rapid breathing" with minimal exertion
• Metabolic acidosis (e.g., DKA) - compensatory Kussmaul breathing
• Anxiety / panic disorder - psychogenic dyspnoea; may produce hyperventilation syndrome with lightheadedness, perioral tingling
• Post-COVID syndrome
• Drug overdoses (e.g., salicylates)
• Severe sepsis / systemic disease

Acute vs. Chronic

• Acute: MI, acute heart failure, severe hypertension, pulmonary embolism, pneumothorax, upper airway obstruction, anaphylaxis, acute asthma
• Subacute/Chronic (>1 month): COPD, ILD, heart failure, pulmonary hypertension, deconditioning, neuromuscular disease
• Goldman-Cecil Medicine, p. 388; Harrison's 22E, p. 312

Assessment

History

• Character of sensation: Air hunger (heart failure), chest tightness (bronchoconstriction), increased work/effort (airway obstruction, neuromuscular disease), rapid/heavy breathing (deconditioning)
• Onset and course: Acute vs. subacute vs. chronic; episodic vs. continuous
• Precipitants: Exertion, posture, cold air, allergens, cigarette smoke, perfumes, moulds
• Relieving factors: Rest, leaning forward, inhaled bronchodilator, oxygen, diuresis
• Associated symptoms: Wheeze, productive cough, fever, ankle oedema, chest pain, haemoptysis, orthopnoea, PND

Grading: Modified MRC Dyspnoea Scale (mMRC)

Physical Examination

• Tachypnoea, use of accessory muscles, intercostal retractions
• Cyanosis, clubbing, wheeze, crackles, reduced breath sounds
• Signs of heart failure: raised JVP, S3 gallop, peripheral oedema, displaced apex
• Signs of anaemia, thyrotoxicosis

Investigations (Stepwise)

Management

General Principles

• Treat the underlying cause - this is the cornerstone
• In many chronic conditions, dyspnoea persists despite optimal treatment of the underlying disease

Disease-Specific

Symptomatic Relief

• Opioids (low-dose oral morphine) - reduce the sensation of dyspnoea in palliative and severe chronic settings
• Oxygen - beneficial when hypoxaemia is present; evidence for benefit in normoxaemic patients is limited
• Fan to the face - stimulates facial mechanoreceptors (V2 branch of trigeminal nerve), can reduce the perception of dyspnoea
• Pulmonary rehabilitation - improves exercise tolerance and reduces dyspnoea in COPD and ILD
• Anxiolytics/antidepressants - when anxiety is a significant contributor
• Positioning - sitting upright or leaning forward reduces work of breathing

Key Points Summary

1. Dyspnoea is purely subjective - always self-reported; tachypnoea and accessory muscle use are the observable correlates
2. Underlying mechanism involves chemoreceptor activation (air hunger), mechanoreceptor activation (chest tightness), and efferent-reafferent mismatch
3. Pulmonary + cardiac diseases account for 85% of cases
4. Character of sensation helps narrow the diagnosis
5. Orthopnoea/PND strongly suggest left heart failure but also occur in COPD
6. mMRC scale grades functional severity and feeds into GOLD COPD staging
7. A stepwise diagnostic approach (history → CXR/ECG/spirometry → advanced imaging) nearly always identifies the cause

Recent Clinical Guidelines on Dyspnoea Management

1. GOLD 2025 Report - COPD (the most common cause of chronic dyspnoea)

• Use the mMRC Dyspnoea Scale or CAT score to grade symptoms and assign GOLD groups A/B/E
• Follow-up pharmacological management is driven by two "treatable traits": persistence of dyspnoea AND exacerbation frequency

• Persistent dyspnoea on a single LABA or LAMA: escalate to LABA + LAMA combination
• If dyspnoea persists on LABA+LAMA: consider adding ICS if eosinophil count >300/μL
• New 2025 additions: Ensifentrine (a dual PDE3/PDE4 inhibitor) added as a bronchodilator option; dupilumab added for patients with type 2 inflammation

• Patients should receive self-management guidance for breathlessness, stress management, and a written action plan
• Pulmonary rehabilitation recommended for all symptomatic patients

2. ACR Appropriateness Criteria: Chronic Dyspnoea - Noncardiovascular Origin (2024 Update)

3. ACR Appropriateness Criteria: Dyspnoea - Suspected Cardiac Origin (2021 Update, published 2022)

4. 2023 Canadian Thoracic Society (CTS) Guideline on Pharmacotherapy in Stable COPD

5. Japanese Society for Palliative Medicine - Dyspnoea in Advanced Disease (2024)

• Guideline recommendations based on systematic reviews for each clinical question plus expert consensus
• Acknowledges a paucity of evidence for many interventions - calls for more real-world observational studies alongside RCTs
• Supports pharmacological (opioids) and non-pharmacological approaches in palliative context

6. ASCO Guideline: Management of Dyspnoea in Advanced Cancer (2022)

• Screening and regular formal assessment
• Opioids as the primary pharmacological option
• Oxygen therapy (only beneficial if hypoxaemic)
• Non-pharmacological: fan therapy, breathing techniques, psychosocial support

7. ERS Systematic Review: Opioids for Breathlessness in Serious Respiratory Illness (2024)

Clinical implication: The evidence for routine opioid use for chronic breathlessness at home is weaker than previously assumed, and risks may outweigh benefits outside of the palliative/end-of-life setting. Overall certainty of evidence was "very low" to "low".

8. ERS Systematic Review: Breathing Techniques for Serious Respiratory Illness (2024)

Clinical implication: Breathing exercises are safe and consistently improve quality of life. Recommended for inclusion in the care of people with serious respiratory illness, despite modest direct effects on breathlessness scores.

9. ATS 2023 Pulmonary Rehabilitation Guidelines

• Pulmonary rehabilitation is safe and effective for reducing dyspnoea across multiple lung diseases
• Formal evidence base provided to support policy changes improving access
• Dyspnoea, health status, and exercise capacity should all be formally measured as outcomes

10. ERS Guideline on Bronchiectasis (2025)

Summary Table: Guidelines at a Glance

• The strongest evidence for chronic dyspnoea management remains treating the underlying disease (LABA/LAMA for COPD, diuretics for heart failure, antifibrotics for IPF)
• Pulmonary rehabilitation and breathing exercises have good evidence for symptom reduction and quality of life, with no adverse effects
• Opioids for chronic at-home breathlessness are now under greater scrutiny - benefit in daily life is not well established and adverse events are significant; use should be carefully weighed, particularly outside end-of-life care
• Fan therapy (facial airflow) is a simple, safe non-pharmacological adjunct
• Imaging guidance (ACR 2024): start with chest X-ray, use non-contrast CT as second line for most non-cardiac causes

The Puerperium

Definition and Duration

• Gray's Anatomy for Students defines it as: "a 6-week period that begins after the delivery of the placenta, during which the body undergoes changes that revert it to its non-pregnant state."
• Textbook of Family Medicine, 9e: "These changes are normal and should not be confused with a pathologic condition."

Physiological Changes

Uterine Involution

• Uterine contractions ("afterpains") during involution are often painful and may require analgesics
• Breastfeeding promotes uterine contraction and involution by stimulating oxytocin release
• The gravid uterus increases from ~50 g to ~1000 g during pregnancy due to hypertrophy of myometrial smooth muscle, increased blood vessels, and tissue fluid

Lochia (Vaginal Discharge)

Haematological Changes

• Leukocytosis up to 20,000/μL within the first 24 hours (normal physiological response - do not confuse with infection)
• Diuresis: marked urinary output as the 6-8 L of extra fluid acquired in pregnancy is mobilised; may transiently elevate haematocrit
• Pulse rate drops within the first 24 hours
• Temperature may be mildly elevated in the first 24 hours (but fever must prompt search for infection)

Lactation and Breasts

• Milk "let-down" begins in the first days; breasts may become engorged early
• In non-breastfeeding mothers: earliest ovulation at ~4 weeks postpartum, first menses typically 6-8 weeks; lactation suppressed by firm breast support and fluid restriction (symptoms last 3-5 days)
• In breastfeeding mothers: anovulation (lactational amenorrhoea) continues for approximately 10-12 weeks on average; influenced by frequency, duration, and supplemental feeding
• Contraception is needed as ovulation can occur as early as 2 weeks postpartum and conception has been reported at this time

Bladder

• Urine retention and bladder overdistension must be avoided
• Rapid diuresis occurs when oxytocin is discontinued after delivery
• Women must be monitored to prevent asymptomatic bladder overfilling

Menstruation

• Non-breastfeeding: first menses typically returns at 6-8 weeks
• Breastfeeding: typically 10-12 weeks, but highly variable

Management of the Normal Puerperium

Immediate (First Hour)

• Observe for 1 hour post-delivery of placenta
• Uterine massage every 15 minutes to ensure maintained contraction and prevent excess bleeding
• Active management of the third stage: early oxytocin administration (10 units IM or IV infusion), early cord clamping/cutting, and controlled cord traction - reduces PPH by two-thirds
• Initiate breastfeeding if desired

First 24 Hours

• Regular diet as soon as patient desires (after normal vaginal delivery)
• Full ambulation as soon as possible (reduces DVT risk)
• Showers encouraged; vaginal douching prohibited
• Episiotomy pain: hot sitz baths, analgesia (avoid meperidine/pethidine in breastfeeding due to long half-life of active metabolite in infants)
• Bladder monitoring; encourage voiding
• Laxatives if needed; bowel movement ideally before discharge

Discharge

• Rubella immunisation if non-immune (mandates delaying pregnancy 3 months)
• Rhesus immunisation: anti-D immunoglobulin if Rh-negative with Rh-positive infant
• Contraception counselling (see below)

6-Week Postnatal Check

• Assess uterine involution (should be complete)
• Screen for postpartum depression (Edinburgh Postnatal Depression Scale)
• Blood pressure, anaemia, breastfeeding, family planning
• Cervical smear if due

Contraception in the Puerperium

• Medroxyprogesterone acetate (DMPA) injectable: effective but may theoretically reduce milk supply if given immediately postpartum - communicate risk and support autonomous decision-making

Complications of the Puerperium

1. Postpartum Haemorrhage (PPH)

• Primary PPH: blood loss >500 mL vaginal delivery or >1000 mL caesarean section within 24 hours (clinical definition: any bleeding causing/risking haemodynamic instability)
• Secondary PPH: excessive bleeding from 24 hours to 6 weeks after delivery

1. Bimanual uterine massage + compression
2. Oxytocin IV (10-30 units in 1L fluid) or IM (10 units) - first line
3. Methylergonovine 0.2 mg IM every 2-4 hours - second line (contraindicated in hypertension - causes vasoconstriction)
4. 15-methyl PGF2α (Hemabate) 0.25 mg IM every 15-90 minutes (max 8 doses) - prostaglandin, can cause bronchospasm
5. Misoprostol (PGE1) - rectal/sublingual
6. Balloon tamponade, surgical haemostasis, hysterectomy if refractory

2. Puerperal Sepsis

• Rise in temperature (>38°C on 2 of days 2-10 postpartum in classic definition)
• Tachycardia
• Foul-smelling lochia
• Lower abdominal pain and tenderness

• Endometritis (most common)
• Pelvic peritonitis
• Septicaemia

3. Thrombophlebitis and Venous Thromboembolism (VTE)

• The puerperium is a high-risk period for VTE - hypercoagulable state persists up to 6 weeks postpartum
• Thrombophlebitis: infection of leg veins, often associated with varicose veins; leg becomes tender, pale, and swollen
• DVT / Pulmonary embolism: prophylactic anticoagulation indicated in high-risk women
• Combined hormonal contraceptives should be avoided <21 days postpartum and used with caution 21-42 days postpartum if VTE risk factors are present (WHO MEC Category 3-4)

4. Puerperal Mastitis and Breast Abscess

5. Urinary Tract Infection

• Catheterisation during labour, bladder overdistension, and urinary stasis predispose
• Screen for and treat promptly

6. Sub-involution of the Uterus

• Failure of the uterus to involute at the expected rate
• Causes: infection, retained placental fragments
• Presents with prolonged lochia, uterine tenderness, uterus larger than expected for gestational age
• Treatment: antibiotics, surgical evacuation if retained products

Psychiatric Complications of the Puerperium

Postpartum Blues ("Baby Blues")

• Incidence: 40-80% of postpartum women
• Onset: Typically peaks at 4-5 days after delivery
• Features: Mild mood swings, tearfulness, irritability, anxiety, emotional lability, insomnia
• Duration: Self-limiting; usually resolves by day 10-14
• Management: Reassurance, support; no pharmacotherapy required

Postpartum Depression (PPD)

• Incidence: ~10% of childbearing women
• Onset: 24 hours to several months after delivery; can be abrupt
• Features: Persistent low mood, loss of interest, fatigue, poor concentration, guilt, lack of interest in or fear of harming the infant, suicidal/homicidal ideation
• Screening tool: Edinburgh Postnatal Depression Scale (EPDS) - 10-item self-report; score ≥13 likely indicates depression; Question 10 (self-harm intent) must be scrutinised regardless of total score
• Management: Psychotherapy, SSRIs (note: SSRIs used with caution in pregnancy given possible cardiac teratogenicity, but postpartum use is generally considered acceptable); referral to specialist

Postpartum Psychosis

• Incidence: ~0.1-0.25% of deliveries (Maudsley Guidelines)
• Onset: 48-72 hours (or longer) after delivery
• Features:
  • Alternating noisy hyperactivity and mutism/inactivity
  • Disorientation, thought disorder
  • Perceptual abnormalities, hallucinations
  • Rejection of infant ("this is not my baby")
  • Suicidal and infanticidal thoughts - the most dangerous features
• Classification: ~40% predominantly affective, ~20% schizophreniform, remainder self-limited confusional psychoses
• Differential diagnosis: Eclampsia, Sheehan syndrome (pituitary infarction), cerebral venous thrombosis, arterial stroke, ergot-induced psychosis, hypoxic/hypotensive cerebral injury
• Management: Urgent psychiatric assessment; antipsychotics, mood stabilisers; ergotamine must be excluded; hospitalisation usually required - never leave mother alone with infant

Puerperal Care Summary (Public Health / Postnatal Visits)

1. Prevent complications (puerperal sepsis, thrombophlebitis, secondary haemorrhage)
2. Restore mother to optimum health (physical and emotional recuperation)
3. Establish and support breastfeeding
4. Provide family planning services
5. Health education

• Twice daily for first 3 days, then daily until cord drops off (neonatal)
• Maternal: at each visit - temperature, pulse, respiration, breast examination, uterine involution, lochia assessment, urinary/bowel function, perineal/episiotomy care
• 6-week check: Complete involution, haemoglobin, blood pressure, family planning, depression screening
• Monthly thereafter for 6 months, then 2-3 monthly to 1 year in high-risk settings

Key Points at a Glance