Vomiting in neonates

The commonest cause of vomit containing blood is swallowed maternal blood. Swallowed blood often irritates the stomach and causes vomiting. Blood may be swallowed during:

• birth
• breastfeeding.
    Figure 3: Vomited blood (Photo courtesy of Janelle Aby MD)

   

Blood swallowed during birth

No birth is bloodless, whether vaginal or Caesarean, and hence there is the opportunity to swallow blood at birth.

However, the largest amount of blood will be swallowed if there is an antepartum haemorrhage associated with bleeding into the amniotic fluid for at least several hours before birth. This blood may then take several days after birth to clear the gastrointestinal tract (GIT).

Under these circumstances, as well as vomiting blood, the baby may pass malaena stools, rather than meconium.

Blood swallowed during breastfeeding

Many breastfed babies will swallow blood from a cracked and bleeding nipple. Usually the mother is aware of the nipple problem, but not always, as the bleeding may be deeper and painless.

Management of swallowed maternal blood is expectant. If it is swallowed from birth it will eventually clear from the GIT occasionally in the form of mild malaena. The mother's cracked and bleeding nipple will require attention, and she may require lactation advice about nipple attachment. This becomes a transient contraindication to breastfeeding if the mother is hepatitis C positive.

Baby is bleeding

Less commonly, the baby is bleeding. Causes may include:

• Haemorrhagic disease of the newborn (HDN) - this rarely occurs with adequate vitamin K prophylaxis. Babies whose mothers have been taking medications that interfere with vitamin K metabolism (such as anticonvulsants or oral anticoagulants) or babies with liver disease or consumption of clotting factors are at higher risk.
• Stress ulceration babies who are very sick can have stress ulceration of the stomach, as can those treated with drugs such as corticosteroids and indomethacin.

Swallowed baby blood

Babies can swallow their own blood from upper airway trauma, which may occur from:

• vigorous suctioning
• endotracheal tube insertion
• difficulty passing a nasogastric tube.

Babies with gastro-oesophageal reflux can develop reflux oesophagitis, which may bleed.

Usually the origin of the blood is clear from the history, but if there is doubt some laboratories may be able to perform an Apt test (blood mixed with sodium hydroxide). This distinguishes fetal from adult haemoglobin. Contact local pathology service if this is required.

Vomiting bile

Suspect bowel obstruction if bile is green

A baby who vomits bile (green, not yellow) should be presumed to have a bowel obstruction, until proven otherwise.

There are many causes of bowel obstruction including:

• volvulus related to malrotation of the midgut (this is potentially the most dangerous)
• twisted bowel, which can cause the bowel to become ischaemic, necrotic and potentially perforate within a matter of hours, so diagnosis and surgical referral for treatment are urgent
• Hirschsprung disease.

Look for other signs of obstruction

Other signs of obstruction, including bloody diarrhoea, abdominal distention and imperforate anus should be sought. The anus should be carefully inspected for patency to rule this out.

A supine abdominal x-ray will usually reveal an abnormal gas pattern, for example:

• paucity of gas and distention of the stomach and proximal duodenum in volvulus
• more gaseous distention with lower obstructions and a lateral decubitus x-ray will reveal fluid levels.

Treatment of bowel obstruction

Treatment of bowel obstruction includes:

• urgent surgical referral and transfer to a tertiary service with surgical capability
• IV fluids and correction of any electrolyte imbalances
• gastric drainage; nasogastric tube (NGT) insertion to decompress stomach
• antibiotics
• nil orally
• assess the baby for other congenital abnormalities.

Occasional projectile vomiting may occur without a specific cause in some neonates.

Consider duodenal obstruction

Projectile vomiting may indicate duodenal obstruction. Issues related to duodenal obstruction:

• The commonest cause of duodenal obstruction is duodenal atresia. Half of the infants with duodenal atresia will have Down syndrome. However, duodenal atresia is more commonly diagnosed antenatally in a mother who presents with polyhydramnios and in whom the classical ‘double-bubble’ appearance (distention of stomach and first part of duodenum) is seen on antenatal ultrasound.
• If the diagnosis is not made antenatally, the baby may have minimal vomiting until the milk intake increases after the first few days of life. The diagnostic test is an abdominal x-ray, which reveals the classic 'double-bubble' appearance. An upper GIT contrast study should be done to confirm that the double-bubble sign is not due to malrotation.
    Figure 4: Upright abdominal x-ray showing characteristic ‘double- bubble’ sign confirming duodenal atresia.

   

Consider pyloric stenosis

• Pyloric stenosis usually presents at two to six weeks of age after most babies have been discharged home, rarely presenting after 12 weeks. However, it occasionally occurs in the convalescing preterm infant before discharge home. Ultrasound will often help to make the diagnosis.
• The baby will often have a hypochloraemic metabolic alkalosis.

Vomiting in an unwell baby

Consider other possibilities

If an unwell baby is vomiting, consider:

• infection
• inborn errors of metabolism (urea cycle disorders)
• congenital adrenal hyperplasia
• oesophageal atresia
• tracheo-oesophageal fistula
• imperforate anus.
   

Helpful clues include:

• other signs of sepsis (including NEC)
• excessive weight loss (including dehydration)
• disordered conscious state
• metabolic derangements, including metabolic acidosis and electrolyte disturbances (high potassium and low sodium in congenital adrenal hyperplasia).

Vomiting with failure to thrive

Causes

Causes may include:

• gastro-oesophageal reflux (GOR)
• sepsis
• inborn errors of metabolism.

Gastro-oesophageal reflux (GOR)

Characteristics of GOR:

• GOR usually does not present in the first days after birth, probably because milk intake is relatively low. It is usually more pronounced  with artificial formulas compared with breast milk, and most babies are at least initially breastfed. Therefore, most term babies present after discharge home.
• GOR is most commonly diagnosed in nurseries in convalescing preterm babies.
• The vomiting is characteristically effortless and occurs more when the stomach is full (after a feed) and when the baby is lying flat rather than being held upright.
• Occasionally, the vomit may contain blood from reflux oesophagitis.
• In most babies the diagnosis is clinical and partly confirmed by response to anti-reflux measures. Where anti-reflux measures fail, further investigation is necessary for an exact diagnosis.
• Preterm babies have less GOR when nursed prone, but they must have full cardiorespiratory monitoring for apnoea. As babies mature they should be placed on their back on a firm flat mattress that is not elevated or tilted as soon as possible and prior to discharge home.
• Rarely, persistent GOR may require fundoplication.

Treatment of GOR:

• Treatment includes thickening the baby's feeds; smaller, more frequent feeds; minimal handling after feeds.

Issues to note about vomiting that causes choking:

• All babies are capable of choking.
• Sometimes the choking follows vomiting.
• It is particularly common the first day after birth, especially if the baby has swallowed any blood or meconium.
• It is also common when the milk flow is excessive, especially around three to four days of age.
• Most babies cope with these episodes quite well, and either swallow the regurgitated contents or cough them out.
• Recurrent aspiration is usually caused by severe GOR.

Gastroenteritis is less common during primary hospitalisation due to:

• higher breastfeeding rates
• more rooming-in (less care of babies in communal nurseries, where infectious agents such as rotavirus can spread easily)
• hand hygiene practices.

Gastroenteritis can, however, still cause vomiting and diarrhoea in newborn infants leading to dehydration and shock if unrecognised or treated.

• American family physician Bilious vomiting in the newborn
• Photo Gallery Index: Newborn Nursery at LPCH - Stanford University, School of Medicine
• The Newborn Book