2. Blood pressure
It is the product of cardiac output and peripheral vascular resistance so
when the CO or peripheral vascular resistance increases BP also rises.
3. Old definition of HTN
- Borderline: 90-95 percentile
- Mild: 5-9 mmHg above 95 percentile
- Moderate: 10-15 mmHg above 95 percentile
- Severe: More than 15 mmHg above 95 percentile or vital organ
damage
5. Prevalence of hypertension
in children
In infants and young children HTN is uncommon with a prevalence of <1% but when it
is present it often indicates underlying disease process (secondary HTN).
6. Types of hypertension
There are two types of hypertension on the basis of etiology:
1- primary HTN or essential HTN: when no identifiable cause for HTN is found. It is more
commonly observed in school age children and adolescents. Also isolated systolic HTN is
consistent with primary HTN. These patients are mostly obese and a have a strong family
history of HTN.
2- Secondary HTN: when HTN is the result of an underlying disease. It is severe and
symptomatic HTN that is more commonly seen in infants and younger children.
7. Ambulatory BP monitoring
• It is usually used to measure 24hr period it measures BP after around every 20-30 seconds during
usual daily activities and sleep. Also, this type of monitoring is used to differentiate between
white coat HTN and masked HTN. Also, it evaluates the hypotensive episodes when the patient is
taking anti hypertensive therapy.
• White coat HTN: when the infant is afraid in the hospital so the BP increases due to increased HR.
• Masked HTN: when the infant has high ambulatory BP but normal office BP
• But ambulatory BP measurements have some limitations as it can not be performed in patients
that are too young and in the children with developmental delay.
8. BP measurements in
children
The 2017 AAP guidelines suggest that children 3 years or older should have their BP
measured during normal preventive visits unless the child has risk factors eg ; the child
has CKD, DM etc. then the BP should be measured at every healthcare encounter.
Children less than 3years should have BP checked if they have history of prematurity,
congenital heart disease, organ transplantation, Diabetes and cancer etc.
Proper method of measuring the BP: auscultation and a BP cuff of the proper size that
suits the child arm.
elevated readings of the BP should be confirmed on repeated visits to confirm that
the child is hypertensive.
It should be measured in a child with sitting position after a period of quite for 5 min
and the BP should be checked at three different times.
Attention should to be paid to the size of cuff to avoid over diagnosis because a too
short cuff increases the BP readings.
BP should be obtained in all 4 extremities to detect coarctation of aorta.
9. Etiology and age
HTN in premature infants: renal artery thrombosis and umbilical artery
catheterization.
HTN in early childhood: renal disease, COA, endocrine diseases and medications.
In older school going children and adolescents: primary HTN has become more
common.
10. Causes of acute HTN
Renal: HUS, AKI, hypervolemia, pyelonephritis, renal trauma etc.
Drugs: cocaine, tacrolimus, cyclosporine, lead, Vit D intoxication, corticosteroids etc.
Central and autonomic nervous system: burns, stevens-johnson syndrome, increased
intracranial pressure, encephalitis etc.
Causes of chronic HTN
renal: chronic GN, polycystic kidney disease, recurrent pyelonephritis, obstructive
kidney disease and renal tumors etc.
Vascular: COA, renal artery lesions, renal vein thrombosis and vasculitis.
Endocrine: hyperthyroidism, hypercalcemia, primary hyperaldosteronism and cushing
syndrome, mineralocorticoid excess etc.
CNS: intracranial mass, hemorrhage, Quadriplegia, sleep disorder breathing etc.
11. Clinical manifestations
primary HTN:
Usually asymptomatic
And BP mildly elevated on routine exam
Child may be obese.
Secondary HTN:
Ranging from mild to severe, Clinical manifestations may show:
When the HTN is substantial
Underlying disease process
Headache
Dizziness
Epistaxis
Visual changes
And seizures may occur
12. Approach to the patient
Like other diseases the key to approach HTN in children is careful history taking and
PE.
The history should include: the neonatal history, family history, growth parameters,
drug history.
The PE shows the following signs:
General appearance: Growth retardation, edema, pale mucous membrane
Skin: rashes
Eyes: proptosis, extraocular muscle palsy
Head and neck: webbed neck and goiter
Cardiovascular: absence of femoral pulses, murmurs
Pulmonary signs: pulmonary edema
Abdomen: jaundice
CNS: muscle weakness, neurological deficits
Genetalia: ambiguous
Skeletal: short metacarpals
13. Unless the Hx and PE suggest another cause, the children with confirmed HTN should
be evaluated for the presence of renal dx so,
Electrolytes
BUN, Cr
U/A
CBC
Renal ultrasounds should be performed.
Evaluation for comorbidities:
Fasting lipid panels and fasting glucose should be checked.
Evaluation for target organ damage:
Echocardiogram and retinal exam.
Additional testing:
ABPM, Renovascular imaging, Ct angiography, plasma and urine catecholamines.
Diagnosis
14. prevention
Primary HTN can be prevented by:
Controlling obesity
Increasing physical activities in schools and communities
Lowering sodium intake
Increasing potassium, ca and mg containing food
15. Treatment
If the HTN is confirmed in a child and HTN is asymptomatic and mild evidence of end organ
damage then the mainstay of therapy is lifestyle modification with dietary changes and
regular exercise.
In obesity related HTN, weight loss is the primary therapy. The hypertensive children should
eat fresh vegetables, fruits, fibers etc.
Regular physical activity for atleast 30-60min on most days, and reducing sedentary
activities to less than 2 hours.
Indications for pharmacological therapy:
Persistent HTN despite non pharmacological measures
DM type 1 and 2
Symptomatic HTN
Hypertensive target organ damage
Secondary HTN
16. Anti hypertensive drugs
When indicated the anti hypertensive drugs should be started with single drug and
lowest dose then dose can be increased till the goal BP is achieved.
When the maximum dose of a drug is reached or side effects are observed then 2nd
drug is added from a different class.
Acceptable drugs for children are: ACEs, ARBs, Ca channel blockers, diuretics and
vasodilators.
The goal of drugs is to maintain the BP below 95th percentile except for patients with
CKD, diabetes and end organ damage when the BP should be less than 90th percentile.
ACEs can be used for HTN with Diabetes and microalbuminemia and proteinuric renal
dx.
B-blockers and Ca channel blockers can be used for HTN with migraine.
