“My baby is vomiting, doctor, what is wrong with him?”

This query is often posed by anxious mums, dads or grandparents to the doctor, be it in the clinic, hospital ward or nursery, or in the emergency department.

So, why do babies vomit?

When should doctors be more alert to the possibility of a more serious problem? And when do parents need to start worrying when their baby vomits?

Babies vomit for many reasons.

Thus, a detailed history as to amount and colour of the vomit, how often it occurs, when it occurs, and any other associated symptoms, such as fever, pain or change in bowel motions, is necessary.

The causes for vomiting in a newborn are numerous.

It can be due to medical conditions, e.g. infection, or to more sinister surgical pro-blems, such as an intestinal obstruction that requires immediate surgical attention.

So, when do parents and doctors need to be more cautious?

A surgical emergency

The colour of the vomited contents is important.

If it does not contain milk, the cause of the problem is more likely to be a medical condition, like an infection, which will require urgent medical attention, or gastro-oesophageal reflux.

If the vomit is green, it could be a sign of a surgical emergency.

Green vomit, otherwise known as bilious vomit, contains bile produced by the liver that passes into the beginning of small intestine, i.e. the duodenum.

There are many surgical causes of green vomit. The most serious of these conditions is malrotation with volvulus (twisting), which needs immediate surgical attention, as delay in diagnosis and management may result in the baby’s death.

While in the womb, the fetal intestine protrudes outside the abdominal cavity.

It then undergoes a series of rotations and elongations before returning into the abdominal cavity.

This results in the small intestine being located in the centre of abdominal cavity, whereas the large bowel is located at the periphery. Think of this as a framed picture, with the large intestine acting as the frame and the small intestine being the picture.

When this in-utero bowel rotation is incorrect or incomplete, it leads to “malrotation” of the small gut.

A complication of such malrotation is a twisting of the entire small gut (volvulus), which results in no or very little blood supply to it.

This, in turn, causes ischaemia and necrosis (death) of the small bowel in part or in its entirety.

The majority of babies with malrotation and volvulus will present with symptoms in the first month of life.

The baby will suddenly vomit green vomit, is generally less active as he or she is terribly ill, or cries incessantly due to the pain in their tummy.

In the early stages of the twisted bowel, crampy abdominal pain is common.

As it progresses and when the entire bowel is dead, the pain is less severe as there are less and less nerves – and eventually none – to transmit the pain sensation.

The baby may pass out blood and mucus during defecation due to the passage of dead bowel mucosa.

The baby’s abdomen will also get progressively bigger and more tense.

These babies are very sick, inactive, and might even be in a collapsed state if the symptoms have been ongoing for a few days.

Resuscitation of the baby needs to be immediately carried out if that is the case.

Emergency operation

Doctors need to keep in mind the possibi- lity of malrotation and volvulus in such patients.

Imaging studies, i.e. upper gastrointestinal study (contrast meal and follow through), will confirm diagnosis.

However, if an X-ray shows a perforated bowel, then the contrast study is not done and the baby will be taken to the operating room immediately.

Once diagnosis is confirmed, the baby is operated on immediately as a delay may cause more loss of blood to the small bowel. It is a true surgical emergency.

The dead bowel will be removed during the operation.

The survival of the baby is dependent on how much small bowel is affected and the duration of his or her symptoms. If the entire small bowel is affected, i.e. dead, the baby will not survive.

The paediatric surgeon will be very guarded in making a prognosis if the baby comes to them late, and if a lot of the small bowel is affected or dead.

This is one of the most frustrating scena- rios we, as paediatric surgeons, encounter.

In the event the baby survives, the remaining length of small gut is a crucial determinant to his or her overall survival and growth.

We all need a minimal length of small bowel to survive. If the length of the remaining small bowel is less than that minimum, it is known as short gut syndrome.

In the old days, babies with this syndrome would die.

With the advent of total parenteral nutrition and organ transplantation, these babies have hope. (Total parenteral nutrition involves giving all essential nutrients to the patient via a drip, whereas enteral nutrition implies oral intake.)

Other possible causes

There are many more other surgical causes of green vomit in a baby.

These include bowel atresia (blocked small or large intestine), Hirschsprung di- sease (caused by aganglionosis, where there is essentially a loss of the “motor engine” in the gut, resulting in a lack of muscle movement), and necrotising enterocolitis (severe infection of the bowel in newborns), to name a few.

So, if your baby vomits green, please bring him or her to see a doctor as soon as possible.

Doctors also need to consider malrotation with or without volvulus as the diagnosis in all babies with green vomit.

This article is courtesy of the Malaysian Association of Paediatric Surgery. For further information, e-mail starhealth@thestar.com.my. The information provided is for educational and communication purposes only and it should not be construed as personal medical advice. Information published in this article is not intended to replace, supplant or augment a consultation with a health professional regarding the reader’s own medical care. The Star disclaims all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.