Wheezing

We’ve just had our first case of respiratory illness since Talia came home.

When she was discharged from KEMH, we were warned that her chronic lung disease meant that it was very likely she could end up back in hospital with some sort of respiratory infection. So we took every precaution the first winter, staying away from shopping centres and zealously avoiding people with colds. It paid off - not even a sniffle. This year she had a flu vaccination and avoided all but a few minor colds. So I guess we should be very happy that it has been 16 months since she came home before she actually contracted anything even slightly worrying.

Last weekend Talia started coughing, a nasty chesty cough, and by Tuesday she had developed a most impressive wheeze. Maybe not quite as bad as Darth Vader, but loud enough that I could hear her breathing from the next room, over the top of my husband’s electric shaver.

When I called my GP on Wednesday morning they said they were full for the day - but when I said I had a one year old with a bad wheeze they managed to find me a slot very quickly! The doctor thought it might be bronchiolitis, but said that our options were limited. I could try and administer ventolin via a spacer (something I could see Talia struggling against and hating) or if her breathing became more laboured, I could take her to PMH.

Fortunately Talia’s condition remained stable and although the wheezing continued another couple of days and the chesty cough is still with us, I didn’t need to rush her to hospital (thank goodness!) She was tired and not the happiest of little girls, but otherwise handled the week very well.

Now it is a waiting game to see if she develops a wheeze with future illnesses - a possible symptom of asthma - but fingers crossed, hopefully not.

Necrotising enterocolitis (NEC)

What is it?

Necrotising enterocolitis (NEC) is a condition where the bowels (intestines) become infected and inflamed. “Necrotizing” means the death of tissue, “entero” refers to the small intestine, “colo” to the large intestine, and “itis” means inflammation.

Why does it occur?

Most cases of NEC occur in premature babies, typically within the first 2-3 weeks of life and usually after the baby starts receiving milk feeds. The exact cause is not clear, but it seems to occur when a baby’s immune and digestive systems have not yet properly developed. An immature gut may have difficulty absorbing milk. If a baby’s intestines are weak due to low oxygen (due to the body prioritising oxygen to other parts of the body) or poor blood flow, then the stress of food moving through it may result in bacteria that would normally not cause any problems invading and damaging the walls of the intestine. In addition, a premature baby’s immune system may not be able to deal with the resulting infection.

NEC is less common in babies who are fed expressed breast milk rather than formula, possibly due to the anti-bacterial and anti-inflammatory properties of human breast milk.

Why is it a problem?

If a NEC infection becomes severe, it can cause serious damage to or holes in the intestines, and/or infection of the blood or the membrane lining the abdomen. This can be life-threatening in a tiny baby with an immature immune sytem. Even when a case of NEC is mild, doctors must stop milk feeds until the infection clears up, resulting in a baby failing to gain weight at a critical time in its life.

The lower the birth weight and earlier the gestational age of a premature baby, the more likely they are to develop NEC, and the higher their chances of dying from it.

How is it treated?
For babies who have mild to moderate NEC, treatment usually consists of
- “nil by mouth” - stopping milk feeds and using intravenous feeds (ie through a vein) while the bowel recovers
- a course of antibiotics, and
- removing extra fluids and gas from the intestine via a naso- or orogastric tube.
This treatment usually lasts between 3 and 10 days.

If the baby’s abdomen is so swollen that it interferes with breathing, extra oxygen or a ventilator may be used to help the baby breathe. If the baby does not improve with treatment, or if he or she gets a hole in their intestines, it may be necessary to use surgery to remove damaged parts of the intestines.

Unfortunately NEC is difficult to diagnose quickly, as the earliest symptoms can be quite general (eg apnoea and bradycardia, temperature instability) and vary depending on how severe the condition is. Later symptoms include a swollen belly. A diagnosis of NEC is usually confirmed via x-ray (showing air bubbles in the intestines) and blood tests.

Hospital staff try to minimise the risk of a baby contracting NEC by carefully regulating the amount of milk a baby receives, increasing the volume of milk slowly, encouraging mothers to express milk for their baby, and maintaining strict hygiene standards in the NICU.

Are there ongoing complications?

Most babies who develop NEC recover fully and do not have further feeding problems, but in some cases, scarring of the bowel may occur, particularly if surgery was required. This can lead to future problems such as malabsorption (the inability of the bowel to absorb nutrients normally).

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This is one of a series of articles I’ve written for the L’il Aussie Prems newsletter under the heading of Premmie Health. Read my disclaimer here.

Immunisations for premature babies

Talia had her 18 month vaccination this week - the regulation shot against chicken pox, but also an extra dose of Hepatitis B vaccine. I hadn’t realised until I opened her purple health record book that morning that there was a handwritten amendment to her vaccination schedule indicating that she needed this additional shot. The nurse at the central immunisation clinic at Rheola Street told me that it was due to her extremely low birth weight and that babies born under 1000g require this extra shot.

Then I found the following information online at http://www.immunise.health.gov.au Common questions on getting immunised I have highlighted the vaccines they mention.

Premature babies especially need the protection of immunisation because they are more prone to certain infections. In general, babies born prematurely receive the same immunisations as other babies. However, very low birth weight babies may have a lower response to hepatitis B and Hib vaccine. The immunisation requirements of a very low birth weight baby should be discussed with your paediatrician and may include having their antibody response checked after immunisation, a delayed immunisation or an extra dose of the hepatitis B and Hib vaccine. As well, premature babies born at less than 28 weeks gestation require an extra dose of Hib vaccine and pneumococcal vaccine.

So Talia’s hepatitis B has now been taken care of, but what is supposed to be happening with regard to Hib and pneumococcal?

I borrowed a copy of the Australian Immunisation Handbook, 2008 edition and the answers (text taken either directly from the book or summarised as accurately as possible) are as follows:

A fourth dose of Hib vaccine is recommended for preterm babies born 28 weeks gestation or earlier, 1500g or less, if they are vaccinated with PRP-OMP. When other Hib vaccines, including Infanrix hexa, are used, no change in the usual schedule is required. [p136] So if you’re prem and in Perth, you don’t need to do anything because the WA government uses Infanrix hexa (DTPA-IPV-HepB-Hib) for Hib vaccination at 2, 4 and 6 months, plus there is a single Hib shot at 12 months.

All preterm babies born at less than 28 weeks gestation or with chronic lung disease should be offered the 7-valent pneumococcal conjugate vaccine (ie the current pneumococcal vaccine for babies and young children) at 2, 4 and 6 months of age (as per the schedule), with a fourth dose at 12 months of age, and a 23-valent pneumococcal vaccine (the older standard pneumococcal vaccine) booster at 4-5 years of age. [pp89, 244-247] So I need to arrange for Talia to have this fourth dose.

Preterm babies do not respond as well to hepatitis B-containing vaccines as term babies. Thus for babies born at less than 32 weeks gestation or less than 2000g birthweight, it is recommended to give vaccine at 0, 2, 4 and 6 months of age, and give a booster at 12 months of age (unless antibodies are measured and found to be in high enough concentrations).[p157] This is the booster which Talia ended up having this week, at 18 months.

In case you were wondering, Talia has never had any problems with any of her vaccinations. She wails indignantly for about 10 seconds, and then the nurse blows a stream of beautiful bubbles and distracts her completely.

Retinopathy of Prematurity (ROP)

What is it?Finisterre.minti.com

Retinopathy refers to damage to the retina, the light-sensitive membrane lining the back of the eye which is responsible for transmitting images to the brain.

In order to function, the retina requires a network of blood vessels. This blood supply normally develops during pregnancy starting around week 16 and finishing by 36 weeks. If a baby is born prematurely, with the retina’s blood vessel development incomplete, problems can occur. Abnormal blood vessels may develop which can subsequently lead to bleeding and scar tissue formation. In severe cases this may then stretch the retina, pulling it out of position. ROP normally affects both eyes.

Regardless of the gestational age at birth, ROP seems to occur at about 37 to 40 weeks.

Who is at risk from ROP?

ROP mainly affects babies who are born at less than 32 weeks gestation weighing less than 1250 grams. The smaller a baby is at birth, the more likely that baby is to develop ROP. However in over 90% of cases, the ROP is mild and will resolve without treatment.

Other factors contributing to the risk of ROP include anaemia, blood transfusions, breathing difficulties, and the overall health of the baby.

Traditionally high oxygen exposure was believed to be the main cause of ROP, and it was common in the 1940s and early 1950s when hospital nurseries began using excessively high levels of oxygen in incubators. With newer technology and methods to monitor the oxygen levels of babies, oxygen use as a risk factor has diminished in importance.

Why is it a problem?

Most babies who develop ROP have a mild case (referred to as Stage 1 or Stage 2) which does not require treatment. These babies recover completely and the ROP leaves no permanent damage.

However, in a small number of babies, ROP worsens, sometimes very rapidly. If left untreated in more severe cases (Stages 3-5), ROP is one of the most common causes of vision loss in childhood and can lead to lifelong eyesight problems and in very severe cases, blindness. The singer Stevie Wonder was a premature baby who became blind as a result of ROP.

How is it treated?

Premature babies have their eyes checked while they are still in hospital, and again after they have been discharged. Mild cases do not need treatment as they will correct by themselves. If the ROP does not resolve by itself, it will continue to form scar tissue which may threaten to detach the retina. Early detection and treatment (if required) reduces the risk of severe ROP developing.

The usual treatment in Australia for severe ROP is laser therapy. Doctors use lasers to “burn away” the outer edge of the retina to slow or reverse the abnormal growth of blood vessels. Unfortunately, this treatment also destroys some side vision. This is done to save the most important part of a baby’s sight—the sharp, central vision needed for “straight ahead” activities such as reading and driving.

Are there any long term problems if my baby had ROP which resolved?

Babies who had ROP are considered to be at higher risk for developing certain eye problems later in life, such as retinal detachment, nearsightedness, crossed eyes, lazy eye, and glaucoma, but in most cases these eye problems can be treated or controlled.

This is one of a series of articles I’ve written for the L’il Aussie Prems newsletter under the heading of Premmie Health. Read my disclaimer here.

Pre-Eclampsia Awareness Week

I just discovered that this week is Pre-Eclampsia Awareness Week.

I had never even heard of pre-eclampsia until a friend of mine told me it was the reason she needed to have her baby delivered 8 weeks early, four years ago. To be honest, at that time I didn’t have any idea what she had been through. Since my daughter was born I’ve met a lot more women who suffered from this very serious and sometimes life-threatening medical condition and whose babies were born prematurely as a result. In fact even two friends in my new mothers’ group who were able to have full term babies also suffered from pre-eclampsia in the late stages of their pregnancy. It’s a lot more common than I had previously imagined.

The Australian Action on Pre-Eclampsia (AAPEC) has a website at http://www.aapec.org.au with a good FAQ and stories from people who’ve been through it personally.