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Aside

I got an interesting referral from one hospital. It is not really that difficult of a case but it is quite puzzling for the untrained ones, nevertheless interesting.

The mothers’s history is generally unremarkable. She only had some flu-like symptoms during the last trimester of the pregnancy. There was no history of hypertension nor diabetes. Mother’s prenatal visits were timely and regular as this is very much wanted pregnancy. Generally, she never had symptoms. She came to the hospital in labor. She had an ultrasound which stated that the baby is in fine condition, there was adequate fluid. About 12 hours into delivery the bag of waters ruptured. The mom recalled that she noted the fluid to be yellow-stained (normally it should be clear). There was no foul odor.

She gave birth by normal vaginal delivery. The baby was not that big, weighing only 2.6 kgs. There was no difficulty during baby’s delivery. There was no cord loop around the neck (that may have strangulated the baby). The fluid was viscid, thickly saturated with meconium (baby’s first stool). Few minutes thereafter, the baby began to have respiratory distress requiring oxygen support.

Baby had an xray of the chest revealing pneumonia. He was then started on empiric broad spectrum antibiotics. Baby was nursing well from the mother while on oxygen supplementation. There was no progression of the respiratory distress. Despite requirement for oxygen, baby remained comfortable. On the 5th day of life, baby still cant be weaned off from oxygen, breathing was still fast although comfortable. Repeat xray of the chest revealed significant clearing of the pulmonary infiltrates initially seen on the previous xray. An arterial blood gas analysis was done but it was unremarkable. So why then is the baby requiring oxygen despite the comfortable breathing, normal blood gas analysis and clearing of xray picture?

The baby was then referred to me at this time. At first I went with the line of unresolved infection so I suggested shifting of antibiotics as well as determination of c-reactive protein (an indicator of inflammation – often due to infection, that may as well be used to monitor response to treatment).

The CRP was reactive, meaning it indicated presence of an ongoing inflammation/infection, but the value was not congruent with the distress of the baby. So I tried to play along with some of the facts that the baby presented. First, baby was born throught thickly meconium stained amniotic fluid. Second, the baby’s initial xray findings highly suggested pneumonia. Third, the baby remained oxygen dependent despite ample time for antibiotics to have worked, granting this was supposed to be an isolated pneumonia. Fourth, despite improvement of x-ray picture, the baby remained, clinically, unimproved; was still dependent on oxygen support.

With these, I came to rationalize that baby might be having meconium aspiration pneumonia (MAP). (While meconium is supposed to be sterile , meaning it is free of bacteria, antibiotics was a rational modality of treatment as CRP was reactive). But on top of the MAP, I considered that baby might be experiencing as well a complication.

I then requested to obtain blood gas analysis from the right and the left arms, with emphasis on the pulmonary oxygen between the two sites.

pda1

The aorta, the main vessel that arises from the left ventricle (red vessel creating a loop on the above illustration) gives rise to three large vessels that supply the upper part of the human body. The first branch immediately divides into two, one serving as right subclavian artery (that which supplies our right arm) and right carotid artery (that branch supplying to the blood). The second main branch becomes the left carotid artery which also supply our head on the left side whereas the third main branch is the left subclavian artery which supplies our left arm.

There usually is a ductus arteriosus that exists in the fetus and closes permanently about 10 days after the baby is born. It usually arises after the right subclavian and carotid arteries, and before the left subclavian artery. Thus, by origin, the right subclavian artery is usually termed preductal while the left subclavian artery may be, most often, post-ductal. Since preductal vessels include those vessels that send blood supply to the brain, it is also then safe to assume that preductal blood picture also reflects the same blood picture that goes to the brain.

In cases of pathology when the pressure in the right side of the heart is higher than that of the left, and the ductus artery is still patent/open, the unoxygenated blood in the right side may dilute the already oxygenated blood in the left through the ductus arteriosus. In cases therefore involving increased right-sided pressure, the baby tends to be cyanotic from this explanation.

One way of determining whether there is a significant shunting from the right side to the left side via the patent ductus arteriosus is performing a 2-D echocardiography, which exactly measures the pressures between the two sides of the heart. Just compare your obtained pressure from the right side of the heart with the normal values for age and you can immediately say there is elevation of pressure, or simply put pulmonary hypertension. Another way of determination is to obtain blood gas from preductal (right arm) and post ductal (left arm, right foot, left foot) extremities. Then, compare the partial oxygen tension/pressure (pO2). A gradient between right and left of more than 20 mmHg is highly suggestive of right sided pressure, in this case, persistent pulmonary hypertension, of the newborn (also known as persistent fetal circulation).

The baby’s right arm blood pO2 was 81.7mmHg, whereas the left arm pO2 was 42.16mmHg. There was a gradient between right and left arm of 39.1mmHg, way higher than 20mmHg cut off, clearly suggesting that the baby has a pulmonary hypertension. Pulmonary hypertension usually arises when the small supposedly thin capillaries in the lungs that carry blood for oxygenation thickens. With thick pulmonary vessels, the transit of oxygen from lung alveoli to the blood vessels is rendered more difficult and hence the slow or lack of oxygenation of the blood that returns to the heart, making the baby a little bluish. And if the pulmonary hypertension is severe, this “resists” the incoming blood from the heart and is shunted directly into the aorta via the ductus arteriosus, unoxygenated, already diluting the blood that may have successfully went into the lungs for oxygenation (but not sufficiently). This can turn into vicious cycle until the baby’s demise.

In cases however of pulmonary hypertension, where the wall between the right and left atrium has a large communication known as patent foramen ovale, since at the level of atrium there is already mixing of blood between right (unoxygenated) and left (oxgenated) sides of the heart, there may not be an appreciable gradient of pO2 between preductal and postductal blood gas analyses.

Respiratory Distress?

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Service or Martyrdom?

Service or Martyrdom?.

 

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Service or Martyrdom?

This is a retro-blog.

I remember one patient who was referred to me for neonatal care. It was about 4 years ago. A mother had to deliver prematurely by cesarean section because of premature rupture of membrane and uncontrolled uterine contractions.. Baby was 28 weeks gestational age. There was no more room for control of labor, and preparing the baby’s lungs for eventual delivery; the cesarean section had to be done outright. Both parents were employed at that time, so I thought there was no problem about financial resources.

Again, as for all babies being born prematurely, he needed to be administered surfactant. It was night time, banks were closed so there’s no way the father can tender cash at that time. I told him to go to another hospital, secure surfactant with my name as guarantor and sign a waiver for them to pay for the drug in 24 hours. The medicine was released to him and thus I was able to administer it immediately.

(Image courtesy of www.nhlbi.nih.gov/health/health-topics/topics/pda/)

Baby was already being weaned from the respirator, when a new problem arose, a patent ductus arteriosus. This posed a threat as it increased the volume of blood that goes to the lungs for oxygenation and predisposing to a chronic problem: bronchopulmonary dysplasia. Oral medication given via tube to treat the problem. Then another problem set in: persistent pulmonary hypertension and renal insufficiency bordering renal failure, plus signs of systemic infection showing. I did some double volume blood exchange transfusion here besides giving respective medicines.

Baby’s persistent pulmonary hypertension responded to sildenafil. After the exchange transfusion, baby started urinating. Then the murmur disappeared. However, it took a some time to wean the baby off from the respirator because of one problem: baby developed bronchopulmonary dysplasia. I had to give cocktail of medications. Finally baby was weaned off from the respirator and was extubated but still dependent on oxygen support. There were even times when after extubation and when his BPD would exacerbate, it would require some hourly aerosolization to open up his distal airways.

When baby was almost two months, he was then discharged from the hospital, free from oxygen support, feeding well, and gaining weight daily. Due to big hospital bill, they asked if it is okay for them to sign a promisory note for their payment of my professional fee. Should I say no? I never proposed any condition at all. I just called the hospital to give my approval. They also partially paid their hospital bill.

One week from discharge, they followed up at the clinic. Few days after that, the hospital declared bankruptcy and closed. Then, my fear came true. They disappeared and never came back. They never at least had the courtesy to tell me that they can’t pay my professional fee. Nada! Boom! Ba-bye! I had their number. Sometimes I ask my secretary to remind them, but then they just say they will come to no avail. Then I recall how was I attending to that baby before, I had no car then. I would wait for a cab to visit the baby. Then during early mornings, I had to walk for about 10-15 minutes going to the main road to hail a cab to go back home. And then this is what I deserve.

The perks of a neonatologist. Other colleagues surely do have their own stories and could be worse than this.

 

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My Blue Baby

Gestational HypertensionHealth Insurance

via My Blue Baby.

 
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Posted by on May 19, 2012 in Uncategorized

 

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My Blue Baby

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 (Image credit:  http://www.lhm.org.uk/info/surgical-treatments-for-right-sided-single-ventricle-conditions-48.aspx)

On that day that I admitted three babies successively, there were two premature babies who immediately presented with respiratory distress (of course, it’s expected & understandable), and a full term. I thought that the full term baby was unremarkable until a few minutes after birth when he himself presented with respiratory distress. Initially, I thought it was because of fluid retention in his lungs that caused him to be breathing fast and appearing “bluish.” Fluid retention is usually a common disorder usually experienced by babies delivered via cesarean section (whose mothers did not undergo labor). To some extent, vaginally born babies may also experience transient tachypnea due for fluid retention especially if the labor was precipitous (shorted period than expected). Fluid retention usually resolves in six hours in most babies, but in few cases, may last up to 2-3 days. Babies presenting with such condition will not usually require antibiotic treatment, and will respond often to mere oxygen administration. I initially started the baby on oxygen inhalation.

On the sixth hour of life, the baby remained with fast respiratory rate (tachypnea). We did an x-ray and did a blood test for a marker of infection. Chest x-ray was suggestive of pneumonia whereas the infection marker was non-reactive. Initially, I did not agree with the x-ray findings because the baby has no risk factor of having an infection so I did not start antibiotics yet. The baby’s respiratory rate actually normalized few hours afterwards, but his oxygen saturation was always low, especially when active and crying. This patient’s status and presentation is not compatible with the classical pneumonia cases. Nevertheless I was forced to start antibiotics (at the back of my mind, it’s better act than be sorry if in the end the baby has also a concomitant infection). On the third day, baby remained comfortable, with normal respiratory rate, however, still bluish especially when the nasal cannula delivering the oxygen gets accidentally dislodged from his nostrils. We also noted that the heart beat was stronger in the right side than in the left (which is the normal location of the heart’s tip or apex, and thus stronger heart beat is supposedly appreciated louder from that side). I was considering now that this might be a heart problem. I requested for a repeat chest x-ray to confirm my suspicion of a dextrocardia. (Dextrocardia means that the heart apex is located in the right side, contrary to the normal).

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(Image credit: http://estudandoraras.blogspot.com/2009/05/dextrocardia.html)

Few hours earlier, the baby was evaluated by a cardiologist. A 2D Echocardiography was done and revealed a dreadful finding, it sealed the baby’s fate. The baby indeed has a dextrocardia, but on top of that are more serious findings: situs ambiguous, single atrium, single ventricle, large patent ductus arteriosus, and moderate pulmonary hypertension. This just means, his heart is like that of a fish. I was literally dumbfounded when the cardiologist told me his findings. I dont know how the mother can take it when I will talk to her but I am glad that the burden of telling the mother went to the cardiologist. He would be in a better position than I explaining the baby’s condtion. This would be too heartbreaking on the side of the mother, especially so that she plans to leave for the Middle East after one month to work. Question now is, will she wait for the baby to die before she leaves?

— UPDATE—

Few days after, yesterday to be exact, mother sent me an SMS that baby finally expired. May God bless his soul and take him to His kingdom.

 
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Posted by on May 19, 2012 in Congenital Heart Disease, neonates

 

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