Click here to view next page of this article

 

Hypertension in Children

The most common causes of hypertension in the neonatal period are drugs, such as aminophylline, such as sodium bicarb, we do a lot of things to neonates in the neonatal intensive care unit that can iatrogenically cause hypertension. So in a neonate hypertension, high blood pressure, children you will see things that a baby can be born with, such as hydronephrosis, or infantile or what is called autosomal recessive polycystic kidney disease, something that happens around the birth such as renal vein thrombosis or artery thrombosis, such as - tumor is a little early here - or things that we do; such as putting in lines in the umbilical artery or veins and causing thrombosis and embolization. So thatís what you would think of in a neonate. Of course there is a whole long list of other causes, but to differentiate between the older children and the neonate, in older children the most common cause of hypertension in older children is renal parenchymal diseases.

Older children or young adults, or really the teenagers, the first thing you think of is drugs. Any sort. Illicit or prescribed, such as the pill - the contraceptive pill - or drugs, all the different drugs that are smoked or sniffed or injected cause hypertension. So that would be your first thought in a teenage child, teenage person, with an abrupt onset of hypertension. And thatís how it makes a little bit more sense to think of hypertension by ages. There is, of course, all these other causes; endocrine causes which I wonít even go into, but are very important as causes of hypertension.

Clinical presentation is also different at different age groups, and that in infancy the most important presentation is congestive heart failure. A lot of times baby goes home from the NICU or from the nursery and comes back after a day or two with congestive heart failure. During eating they become cyanotic and sweaty and on exam they are found to be very hypertensive. That is their presentation. Not headaches, blurry vision, etc. So in the neonatal period, it will be more congestive heart failure; not eating well, respiratory distress. Older children can start complaining of headaches, but also it will be more anorexia and other things. Plus, if the cause of it is something renal, as is the more common cause in this age group, you will find polydipsia polyuria, pallor which is already a manifestation of renal failure, and growth retardation.

And indeed, the diagnosis for hypertension is not only for the diagnosis but is also to determine end organ damage. That is again, cardiomegaly and the funduscopic exam and the effect on the kidney. So itís not just for diagnosis of the hypertension, but also what has happened to end organs that are affected by hypertension. For diagnosis of hypertension, according to your suspicions by the findings, presentations and findings, youíll do certain things. Such as renin levels, aldosterone and renin levels.

VMSA scan I already mentioned previously, is a scan that shows if there is or is not renal scarring, parenchymal scarring. Arteriography is very invasive and we donít do as many arteriographies as we used to. We have less invasive tests for renal artery stenosis. And a biopsy is very rarely indicated in hypertension. But if the workup leads to the suspicion of some glomerulonephritis, that would be indicated.

The treatments I just want to mention the possibilities that you have, or the drugs that you have available for hypertensive emergencies. We have the sodium nitroprusside now in the ICU setting, with a drip, and we have labetalol IV and we have nifedipine sublingual. These are all emergency medications for hypertension that is malignant or acute. For more chronic treatment, it depends on the cause. If you are treating a patient with acute renal failure with fluid overload.