Lower respiratory tract infections (adult and child)

The respiratory tract includes the sinuses, nasal passages, pharynx, larynx, bronchi, bronchioles and alveoli. All those parts of the body can become infected with bacteria or viruses. The general term for this is respiratory tract infections. Most respiratory tract infections improve without treatment, but sometimes need clinical intervention.

Infections in the respiratory system are sometimes broken down into:

• upper respiratory tract infections – acute infections of sinuses, nose and throat
• lower respiratory tract infections – acute infections of the lungs and airways (the focus of this guide)

Lower respiratory tract infections tend to last longer and can be more serious. However, they are usually self-limiting, lasting 7–10 days, and can be managed via self-care or parental care.

Most lower respiratory tract infections affect the airways apart from pneumonia, which is an infection of the lung tissue (alveoli).

There are many different types of lower respiratory tract infections, as outlined in Table 1. 

Lower respiratory tract infections often begin as a cold or influenza. They will either be caused by a viral or bacterial infection.

A sputum sample may help to differentiate between the two and will aid decisions about antibiotic selection, as viruses do not respond to antibiotics. However, sputum tests are usually only undertaken where the patient is showing signs of moderate-severity pneumonia (NICE, 2023b).

Assessment includes:

• history of onset and duration of symptoms
• chest examination and auscultation
• the type of cough (dry or productive)
• observations of breathlessness, chest movements, wheeze, pleuritic pain and fever
• smoking status
• temperature, pulse and respiratory rate

In older people, there may be altered consciousness, so typical symptoms such as cough and fever may be absent (NICE, 2023b)

Assessing severity – adults

Be alert for signs of more serious disease, especially in those over 65 years of age, pregnant, obese, immunocompromised or with underlying lung conditions, such as:

• extreme dyspnoea and/or chest pain
• symptoms that are not improving
• feeling confused, disorientated and drowsy
• haemoptysis
• cyanosis

In these instances, assess for community- or hospital-acquired pneumonia using the CRB – 65 score, and consider investigations such as:

• pulse oximetry — arrange urgent hospital admission for people who require supplemental oxygen
• C-reactive protein test — The level of C-reactive protein in

Self-management - adults

Most lower respiratory tract infections are self-limiting (7-10 days) and patients can be advised to:

• get plenty of rest
• increase their fluid intake to loosen the mucus and encourage expectoration
• use extra pillows at night to prop the up to help them breathe
• use simple analgesics such as paracetamol to reduce fever, headaches and muscle pain
• make a hot lemon and honey drink to relieve a sore throat, by adding the juice of half a lemon and 1-2 teaspoons of honey to a mug of hot water
• avoid or stop smoking
• consult a community pharmacist for symptomatic relief such as:
  • nasal decongestants
  • antipyretics such as paracetamol or Ibuprofen
  • expectorants such as Guaifenesin
  • note that most commercial cough medicines do not work (NICE, 2023b)

Management by parents or carers of children at home

• allow the child to rest
• regularly observe the child’s breathing and temperature to make sure it

Antibiotics are generally reserved for those who are systemically very unwell or at higher risk of complications. On average, they only reduce the duration of symptoms by about half a day and can result in side effects such as nausea and diarrhoea. Unnecessary prescriptions can give rise to antibiotic resistance (NICE, 2023b).

Nursing and Midwifery Council: standards of proficiency for registered nurses

Part 1: Procedures for assessing people’s needs for person-centred care

1. Use evidence-based, best practice approaches to take a
history, observe, recognise and accurately assess people
of all ages

Part 2: Procedures for the planning, provision and management of person-centred nursing care

8.2 manage the administration of oxygen using a range of routes and best practice approaches

11.8 administer medications using a range of routes

National Institute for Health and Care excellent (NICE). Rapid guideline for managing COVID-19. https://www.nice.org.uk/guidance/NG191 (accessed 8 January 2024)

NHS England. Sepsis. 2022. https://www.nhs.uk/conditions/sepsis/ (accessed 8 January 2024)

References

Alder Hey Children’s NHS Foundation Trust. Care of a child with a chest infection. 2023. https://www.alderhey.nhs.uk/conditions/patient-information-leaflets/care-of-a-child-with-a-chest-infection/ (accessed 8 January 2024)

Almond, S Mant, D Thompson, M.  Diagnostic safety-netting. Br J Gen Pract. 2009;59(568):872-874. https://doi.org/10.3399/bjgp09X472971 

National Institute for Health and Care Excellence. Scenario: treatment of influenza. 2023a. https://cks.nice.org.uk/topics/influenza-seasonal/management/treating-influenza/ (accessed 2 March 2022)

National Institute for Health and Care Excellence. Chest infections – adult. 2023b. https://cks.nice.org.uk/topics/chest-infections-adult/ (accessed 1 March 2022)

National Institute for Health and Care Excellence. Bronchiectasis. 2023c. https://cks.nice.org.uk/topics/bronchiectasis/ (accessed 2 March 2022)

National Institute for Health and Care Excellence. Scenario: acute exacerbation of asthma. 2023d. https://cks.nice.org.uk/topics/asthma/management/acute-exacerbation-of-asthma/ (accessed 2 March 2022)

National Institute for Health and Care Excellence. Scenario: community-acquired pneumonia. 2023ehttps://cks.nice.org.uk/topics/cough-acute-with-chest-signs-in-children/management/community-acquired-pneumonia/ (accessed 2 March 2022)

National Institute for Health and Care Excellence. How should I assess a person with cough? 2023f.