Apnea is defined as sudden cessation of breathing for more than 20 seconds in full term babies.
It is often associated with Bradycardia and cyanosis.
Causes of Apnea
- Immaturity of the respiratory Centre of the brain
- Infections: meningitis ,encephalitis
- Cardiovascular: Anemia, hypo / hypertension, patent ductus arteriosus,coarctation of the aorta (conditions that impair oxygenation)
- Pain: Acute and chronic
- Central nervous system: Intraventricular haemorrhage, intracranial haemorrhage, brainstem infarction or anomalies, birth trauma, congenital malformations (conditions that will increase intracranial pressure)
- Respiratory: Pneumonia, intrinsic / extrinsic mass or lesions causing airway obstruction, upper airway collapse, atelectasis, respiratory distress syndrome, meconium aspiration, pulmonary haemorrhage(conditions that cause impairment of ventilation and oxygenation)
- Gastrointestinal: Oral feeding, bowel movement, gastro esophageal reflux, necrotizing enterocolitis
- Metabolic: Hypoglycemia, hypocalcaemia, hypo / hypernatraemia, hyperammonaemia, low organic acids, hypo / hyperthermia
- Drugs: Maternal prenatal exposure drugs through transplacental transfer and post nata exposure e.g. opiates, high levels of phenobarbitone, or other sedatives, general anesthetic
- Head and neck poorly positioned
- Toxin exposure
Types of Apnea
- Central apnea: occurs due to depressed respiratory center
- Obstructive apnea: occurs due to obstruction of the airway
- Mixed apnea: a period of central apnea, typically followed by airway obstruction
NB: Short episodes of apnea are usually central whereas prolonged ones are often mixed
Clinical features of apnea
Check the infant for signs of breathing and skin colour, if apnoeic, pale, and cyanotic or has Bradycardia give tactile stimulation
Find out about the frequency and duration of episodes, level of hypoxia and degree of stimulation needed.
If possible diagnose and correct potential aetiologies including prematurity
Note: If the infant doesn’t respond, use bag and mask ventilation along with suctioning and airway positioning
Management of Apnea
- All neonates less than 34 weeks gestation should be routinely monitored with cardio-respiratory and oxygen saturation monitors for at least the first week of life or until there has been an absence of apneic episodes for at least 7 days.
- Above 34 weeks gestation neonates only need to be monitored if they are unstable:.
- Positioning: Ensure the neonate’s head and neck are positioned correctly (head and neck in neutral position) to maintain a patent airway.
- Tactile stimulation: Gentle rubbing of soles of feet or chest wall is usually all that is required for episodes that are mild and intermittent.
- Clear airway: Suction mouth and nostrils.
- Provision of positive pressure ventilation: May be required until spontaneous respirations resume. If positive pressure ventilation is required to treat apneic episodes mechanical ventilation should be considered.
- Continuous Positive Airway Pressure (CPAP); is effective in treating both mixed and obstructive apnea but not central. It’s most commonly delivered by nasal prongs or endotracheal tube. It works by improving lung volume and reduces inspiratory duration hence preventing airway collapse. It also increases stabilization of the chest wall musculature
- Pulse oximeter. Detect changes in the heart rate, respiratory rate and oxygen saturation due to apnoeic episodes.
- Identify cause: If apnea is not physiologic, investigate to identify underlying cause and treat appropriately.
- Apnea monitor: This detects abdominal wall movement and may alarm falsely with normal periodic breathing.
- Caffeine citrate: it can be given orally or intravenously and is usually routinely given to neonates <34 weeks gestation. It acts as a smooth muscle relaxant and a cardiac muscle and central nervous system stimulant.
- High flow nasal Cannular (HFNC): This is especially effective with mixed and obstructive apneas. Often used when treatment with caffeine has failed.
- Mechanical ventilation: This is used when caffeine and HFNC and CPAP have been tried and there are still significant apneas. It is effective in all types of apnea.
Methylxanthine: Theses block adenosine receptors. Adenosine inhibits the respiratory drive thus blocking inhibition, the methylxanthines stimulate respiratory neurons resulting in an enhancement of ventilation.
- Caffeine citrate: (has a longer half life and is less toxic therefore preferred for routine management especially in prematurity)
Loading dose- 20mg/ml either IV or P.O
Maintenance dose 5mg/kg/day
- Theophylline: (it’s a bronchodilator therefore advantageous in neonates with bpd because if treats both apnea and bronchospasm)
Loading dose- 6mg/kg/dose IV or PO
Maintenance dose- 6mg/kg/day divided 6 hourly.
- Ensure all episodes are clearly documented with the intervention that was required to correct them. Also note the frequency and duration of episodes.
Family centered care
- Ensure that parents are aware of the cause of the apneas and how it is being treated e.g. antibiotics for infection
- Ensure the parents of premature babies are aware that Apnea of Prematurity is a normal occurrence and will resolve by the time 34 weeks gestation is reached
- Explain all interventions and why they are necessary e.g. caffeine, CPAP(continuous positive airway pressure) or full ventilation