Respiratory Flashcards
What is bronchiolitis?
Inflammation and infection in the bronchioles, generally considered to occur in children under 1 year.
Aetiology of bronchiolitis?
Respiratory syncytial virus (RSV).
Presentation of bronchiolitis.
- coryzal symptoms
- signs of respiratory distress
- dyspnoea
- tachypnoea
- poor feeding
- mild fever
- apnoeas
- wheeze and crackles on auscultation
Signs of respiratory distress.
- tachypnoea
- use of accessory muscles
- intercostal and subcostal recession
- nasal flaring
- head bobbing
- tracheal tugging
- cyanosis
- abnormal airway noises
Define the characteristics of:
a) wheezing
b) grunting
c) stridor
a) whistling sound caused by narrowed airways, typically heard during expiration.
b) exhalation with the glottis partially closed, increasing positive end-expiratory pressure.
c) high pitched inspiratory noise caused by obstruction of the upper airway, for example in croup.
Typical RSV course.
- URTI with coryzal symptoms.
- Spontaneous resolution within a few days OR:
- Chest symptoms
Symptoms usually last 7-10 days, and patients fully recover within 2-3 weeks.
When to admit a child with bronchiolitis.
- aged <3 months
- prematurity
- Downs syndrome
- CF
- <75% normal milk intake
- clinical dehydration
- RR >70
- SpO2 <92%
- moderate to severe respiratory distress
- apnoeas
- parents not confident in their ability to manage at home
Management of bronchiolitis.
Patients typically only require supportive management:
- ensuring adequate food and fluid intake (e.g. NG / IV tube)
- saline nasal drops and nasal suctioning to clear nasal secretions
- supplementary oxygen
- ventilatory support if required
What are the types of ventilatory support available for children?
- High-flow humidified oxygen via a tight nasal cannula. This delivers air and oxygen continuously with some added pressure.
- Continuous positive airway pressure (CPAP). This delivers oxygen continuously with high pressure added.
- Intubation and ventilation. This involves inserting an endotracheal tube into the trachea to fully control ventilation.
How is ventilation assessed in children?
Capillary blood gas monitoring.
What are the signs of poor ventilation on capillary blood gas in children?
Rising pCO2 - showing the airways have collapsed and can’t clear waste carbon dioxide.
Falling pH - showing CO2 is building up and causing a respiratory acidosis.
What can be used to prevent bronchiolitis in high-risk babies.
For babies who are ex-premature and those with congenital heart disease, administer Palivizumab.
It is a monoclonal antibody that provides passive immunity to RSV, therefore a monthly injection is required.
Acute asthma presentation.
- progressive shortness of breath
- signs of respiratory distress
- tachypnoea
- expiratory wheeze on ausculation heard throughout the chest
BTS (2016) criteria for moderate asthma exacerbation.
- PEFR >50% predicted
- normal speech
BTS (2016) criteria for severe asthma exacerbation.
- PEFR <50% predicted
- SpO2 <92%
- unable to complete sentences in one breath
- signs of respiratory distress
- tachypnoea
- tachycardia
BTS (2016) criteria for life threatening asthma exacerbation.
- PEFR <33% predicted
- saturations <92%
- exhaustion and poor respiratory effort
- hypotension
- silent chest
- cyanosis
- altered consciousness / confusion
General management of acute asthma exacerbation.
- supplementary oxygen
- bronchodilators
- steroids
- antibiotics if bacterial cause is suspcected
Management of mild asthma exacerbation.
Manage as an outpatient with regular salbutamol inhalers via a spacer (4-6 puffs every 4 hours).
Management of moderate / severe asthma exacerbation.
- Salbutamol inhalers via a spacer device.
- Nebulisers with salbutamol / ipratropium bromide
- Oral prednisolone
- IV hydrocortisone
- IV magnesium sulphate
- IV salbutamol
- IV aminophylline
Use a stepwise approach and escalate after each step; escalate for anaesthetics to consider intubation and ventilation.
Monitoring when using salbutamol inhalers.
Monitoring of U&Es required as salbutamol causes potassium to be absorbed from the blood into the cells (hypokalaemia).
When is discharge for an acute asthma exacerbation considered?
When the child is well on 6 puffs every 4 hours of salbutamol. They can be prescribed a reducing regime of salbutamol to continue at home.
Consider:
- finish the course of steroids if they were started
- provide safety-net information about when to return to hospital or seek help
- provide an individualised asthma action plan
What is chronic asthma?
A chronic inflammatory airway disease leading to variable airway obstruction.
The smooth muscle in the airways is hypersensitive, and bronchoconstricts when responding to stimuli.
Presentation suggesting chronic asthma.
- episodic symptoms with intermittent exacerbations
- diurnal variability
- dry cough with wheeze and shortness of breath
- typical triggers
- family history / personal history of atopy
- bilateral wheeze
- symptoms improve with bronchodilators
What features in the presentation would indicate a diagnosis other than asthma?
- wheeze only related to coughs and colds
- isolated or productive cough
- normal investigations
- no response to treatment
- unilateral wheeze