Investigation and management of childhood sleep apnoea

Abstract

Sleep-disordered breathing includes disorders of breathing that affect airway patency, e.g. obstructive sleep apnoea syndrome, and also conditions that affect respiratory drive (central sleep disorders) or cause hypoventilation, either as a direct central effect or due to peripheral muscle weakness. Obstructive sleep apnoea syndrome (OSAS) is an increasingly-recognised clinical entity affecting up to 5.7% of children, which, if left untreated, is associated with adverse effects on growth and development including deleterious cognitive and behavioural outcomes. Evidence exists also that untreated OSAS impacts on cardiovascular risk. Close attention should be paid to assessment and investigation of this relatively common condition, instigating early and appropriate treatment to children with OSAS. First-line treatment in younger children is adenotonsillectomy, although other treatment options available include continuous positive airways pressure (CPAP), anti-inflammatory therapies (nasal corticosteroids and anti-leukotrienes), airway adjuncts and orthodontic appliances. Central sleep-disordered breathing may be related to immaturity of respiratory control and can be associated with prematurity as well as disorders such as Prader-Willi syndrome. In some cases, central apnoeas occur as part of a central hypoventilation disorder, which may be inherited, e.g. Congenital Central hypoventilation Syndrome, or acquired, e.g. Arnold-Chiari malformation, brain tumour, or spinal injury. The treatments of central breathing problems depend upon the underlying aetiology.

Keywords: CPAP; OSAS; Sleep-disordered breathing; adenotonsillectomy; cognition; continuous positive airways pressure; obstructive sleep apnoea syndrome; polysomnography.

Figure 1. Obstructive events during sleep measured using limited-channel polysomnography (Source: Sleep Laboratory, Royal Hospital for Sick Children, Edinburgh). SpO2: Arterial oxygen saturations measured by pulse oximetry, Flow Th: Airflow measured by thermistor, RIP Thorax: Thoracic respiratory effort measured by inductance plethysmography, RIP Abdomen: Abdominal respiratory effort measured by inductance plethysmography

Figure 2. Central events during sleep measured using limited-channel polysomnography (Source: Sleep Laboratory, Royal Hospital for Sick Children, Edinburgh). SpO2 : Arterial oxygen saturations measured by pulse oximetry, Flow Th: Airflow measured by thermistor, RIP Thorax: Thoracic respiratory effort measured by inductance plethysmography, RIP Abdomen: Abdominal respiratory effort measured by inductance plethysmography

Figure 3. Overnight oximetry findings in a child with OSAS (Source: Sleep Laboratory, Royal Hospital for Sick Children, Edinburgh). SpO2 : Arterial oxygen saturations measured by pulse oximetry

Figure 4. a) Response of repeated central apnoeas to oxygen treatment, b) In air, c) In oxygen at 0.25 L/minute (Source: Sleep Laboratory, Royal Hospital for Sick Children, Edinburgh). ECG: Electrocardiogram, SpO2: Arterial oxygen saturations measured by pulse oximetry, Flow Th: Airflow measured by thermistor, RIP Thorax: Thoracic respiratory effort measured by inductance plethysmography, RIP Abdomen: Abdominal respiratory effort measured by inductance plethysmography

Figure 5. Illustration of central hypoventilation in association with an intracerebral tumour a) Prior to commencing ventilatory support, b) On ventilation (Source: Sleep Laboratory, Royal Hospital for Sick Children, Edinburgh). ECG: Electrocardiogram, SpO2: Arterial oxygen saturations measured by pulse oximetry, Flow Th: Airflow measured by thermistor, RIP Thorax: Thoracic respiratory effort measured by inductance plethysmography, RIP Abdomen: Abdominal respiratory effort measured by inductance plethysmography