Asthma is a common medical condition caused by narrowing of the airways (breathing passages). The narrowing of the airways occurs due to airway swelling, increased mucous production, and tightening of the muscles around the airways. Patients with asthma usually have cough, wheezing and breathing difficulties and sometimes can have life threatening episodes of breathlessness and need hospital admission. These symptoms can cause exercise limitation and disrupt sleep. The diagnosis of asthma can be relatively straightforward with classic symptoms, triggers, and respond well to therapy or can be challenging with less common presentations. Diagnosis of asthma is particularly challenging in toddlers as clinical manifestations can be atypical or overlap with those of other diseases such as airway, lung abnormalities, bacterial infections, or foreign body inhalations.
Preschool children may have up to 6-10 viral colds a year and are not concerning if they recover within 2-3 weeks, are well in between and are thriving. However, any lower respiratory tract infection presenting with respiratory distress warrants review (GP or Emergency) and prompt evaluation. Although there is no definite consensus on what constitutes recurrent lower respiratory tract infections, three or more annual episodes of bronchitis, bronchiolitis, or pneumonia needs further evaluation. Recurrent pneumonia is defined as two or more episodes of radiologically documented pneumonia in a single year or three or more episodes ever, with a normal chest x ray between the episodes.
Noisy breathing is common in children particularly in infants. In a study involving 298 infants, 30% of mothers of infants reported noisy breathing. However only 1% described the noisy breathing as stridor. The other noises were airway snuffles (93%), wheezing (2%) and chesty sounds (3%). Stridor, is usually high-pitched sound, produced as the result of turbulent airflow from narrowed large, mostly extra-thoracic airways, although it can originate from any level of the airway and can be present during inspiration, expiration, or both. Stertor is a low-pitched, mainly inspiratory sound that may be produced by obstructing lesions of the nasopharynx (adenoid hypertrophy), oropharynx (micrognathia, macro-glossia and tonsil hypertrophy), and hypopharynx (tongue base mass and pharyngomalacia). The most common cause of chronic stridor is laryngomalacia (45% to 75% of cases). Mild cases of laryngomalacia are usually followed clinically and managed conservatively. Occasionally, patients require further workup, subspecialist evaluation, and management.
Besides laryngomalacia which is common cause of stridor, children can stridor due to less common airway anomalies such as airway narrowing (subglottic stenosis), infections, bronchial web, and vocal cord paralysis or airway foreign body inhalation. Recurrent or chronic bronchitis can be from airway anomalies such as tracheomalacia and/or bronchomalacia which cause impaired airway clearance and predispose to secondary bacterial infections after viral infections. Lung anomalies have an incidence 1 in 2500 to 1 in 8000 live births. Nearly 80% of the lung anomalies are diagnosed antenatally with remainder diagnosed after birth. Children with congenital lung anomalies present with wheezing, pneumonia or can be asymptomatic and often detected on chest X-ray. Chest CT scan is required for definitive diagnosis.
Obstructive sleep apnoea (OSA) is a medical condition that causes breathing difficulties during sleep. The relaxation of upper airway muscles in sleep can contribute to partial or complete airway obstruction of an already narrowed airway in children with risk factors for narrowed airway. This is manifested by snoring and pauses in breathing. Although snoring is a common symptom in children, not every child who snores has OSA. Snoring occurs in nearly 10-20% of children while OSA is less common, and only affects about two to three per cent of children. OSA causes sleep disruption and causes daytime tiredness, behavioral difficulties and if untreated can cause adverse consequences on cardiovascular and neurological outcomes.
The most common cause of OSA in childhood is enlargement of the tonsils in the back of the throat, adenoids in the back of the nose, and turbinates (small bony structures) in the breathing passage. Tonsils and adenoids grow most quickly between the ages of two and seven years old. Sometimes, the adenoids grow back again. Other causes of OSA include obesity, long-term allergy or hay fever and medical conditions associated with muscles weakness or low muscle tone, small jaws, or flat faces in children. If you suspect your child has OSA, see medical attention. The doctor may suggest your child has overnight monitoring, either in hospital or at home. This may help diagnose OSA.
Having the tonsils and adenoids taken out cures OSA in 80–90 per cent of children. Children who have surgery to remove their tonsils and adenoids may need to come back to the sleep clinic after the surgery. This might be the case if their sleep study showed severe OSA or if their symptoms do not get better six to eight weeks after the surgery. Although most children will be cured by the surgery, a few may still snore or have difficulty breathing when they are asleep. If your child is still showing symptoms of OSA, tell your doctor. Your child may need some more tests or treatment.
We perform sleep studies in Children from 6 months to 18years through our Clinic at Mater Hospital Pimlico.
Sleep requirements change with age and differ between different children. An average newborn sleeps 16-18 hours per day with sleep-wake periods in 3-4-hour cycles throughout the day and night. By school age sleep is usually consolidated into one-night sleep of 11-12 hours. The duration of sleep then reduces to 10 hours in pre-pubertal children to 7-9 hours by 16 years of age. Night wakings are common during childhood, are part of normal developmental patterns and are mostly transient, however problematic night wakings may persist for months or years and disrupt child and family functioning. Fortunately, most night wakings are amenable to simple measures. Night wakings could from dyssomnias (difficulty falling asleep or staying asleep) or parasomnias (incomplete arousal from sleep) such as night terrors, nightmares, sleep walking or teeth grinding (bruxism).
Cough is a protective reflex to clear secretions and particles from the airways. Cough affects about 30% of children at any given time with majority are due to respiratory tract infections. Cough can be due to infections, allergic conditions, inhaled foreign body, enlarged adenoids and tonsils, chronic infective lung conditions, aspiration and so on. Persistent moist cough lasting > 4 weeks is abnormal and needs further evaluation. Cough not responding to treatment or having feeding difficulties or having associated noisy breathing also warrants further evaluation.