Respiratory problems make up greater then 50% of the acute paediatric workload.
This article aims to provide an overview of the presentation, pathology and
management of the common paediatric respiratory problems.
Children admitted with acute respiratory problems generally present with some
degree of respiratory distress. They may also have cough, noisy breathing or
pain (usually in the chest but sometimes in the abdomen). Occasionally young
infants may stop breathing (apnoea). In children who cannot express themselves
verbally parents may recognise some of the signs of respiratory distress; whether
these should be viewed as symptoms or signs is largely academic.
The child with respiratory distress is working harder to maintain normal blood
O2 and CO2 levels (i.e. he/she is breathing faster and more deeply - increased
rate and larger tidal volume). In this context it is secondary to some problems
with the lung (though some of the features may occur in the child with cardiac
problems or even a metabolic acidosis e.g. diabetic ketoacidosis - this author
has seen a young child with a blood glucose of 48mmol/l treated as bronchiolitis).
Breathing harder, of course, requires more effort leading to increased oxygen
demands, greater CO2 production and, if severe, exhaustion.
Increased Respiratory Rate
Increased respiratory rateis the commonest sign of respiratory distress
(and may be the only sign in some children with a respiratory pathology). Infants
and young children have a limited ability to increase their tidal volume. Hence
when their breathing is compromised in some way they have to increase their
rate of breathing in an attempt to increase blood oxygenation and CO2 elimination.
(Those of you with any memory of respiratory physiology will recall this works
well for the latter, but is not a good way of increasing oxygenation).
Recession is produced when increased effort is put into breathing. In older
children, and adults this increased effort is the result of increased use of
accessory muscles. This produces higher negative pressures inside the chest
cavity on inspiration. The result is that soft tissues are 'sucked in' between
the bones of the chest wall producing intercostal (and sometimes suprasternal/supraclavicular)
Infants and younger children breath mostly with their diaphragm and have poorly
developed accessory muscles. Thus increased respiratory effort largely involves
more forceful (and rapid) contraction of the diaphragm. They also have softer
bones that tend to flex with the soft tissues. These combine to producing costal
and even sternal recession where the sternum is drawn in (sometimes quite alarmingly)
with each breath. Tracheal tug is essentially a form of recession. In more severe
cases this may manifest as 'head bobbing'.
Poor feeding (or difficulty sucking on the breast/bottle) is often reported
in infants with respiratory problems. It can be thought of as shortness of breath
A dry cough or cough on exertion may indicate asthma. A seal like bark is heard
in croup. Nocturnal cough may be a feature of asthma (often dry) or upper airway
(nasal) secretions (usually sounding productive). Though coughs in young children
may sound productive sputum is rarely expectorated.
Whooping cough typically presents as bouts of coughing which distress the child
and may cause cyanosis. They are sometime accompanied by an inspiratory 'whoop'
as the child struggles to breathe before the next cough. Protracted coughing
(in whooping cough or other illness) frequently leads to vomiting in infants
and younger children.