Hypertensive emergencies

1. BY Dr. BN RAVINDRA
Moderator: Dr. SHEETAL

2.  Occurrence: Infrequent
 Classification: Arbitrary
 Def. of Hypertension in children:
 SBP or DBP ≥ 95th percentile on 3 or more occassions
 Stage 1: SBP or DBP b/n 95th and 5mm above 99th
percentile
 Stage 2: SBP or DBP ≥ 99th percentile + 5 mm of Hg (
evaluation should be prompt and immediate
pharmacological therapy is advised)

3. Hypertensive Emergency
 Def:
 An acute severe life threatening elevation in BP with
evidence of potentially life threatening symptoms or
target organ damage
 Commonly involved: Brain, kidneys, eyes, heart
 BP SHOLD BE LOWERED IMMEDIATELY WITH
INTRAVENOUS ANTIHYPERTENSIVE AGENTS

4.  How do they manifest?
 Commonly as HYPERYTENSIVE ENCEPHALOPATHY
i.e., severe BP elevation with neurological symptoms
such as lethargy, coma and/or seizures
 Others : Cardiopulmonary manifestations (congestive
heart failure, pulmonary edema)
 AKI

5.  The absolute level of BP elevation is less important
than whether symptoms and/all target end organ
damage is present.
 Ex – child with chronic hypertension may have high BP
with no symptoms , whereas a child with acute rise in
BP may have symptoms with only moderately raised
BP

6. Hypertensive Urgency
 An acute severe elevation in BP WITHOUT
symptoms or target organ damage.
 The duration of hypertension : whether acute or
chronic is an important determinant of intervention.

7. Whenever a child presents to ED with acute severe
hypertension , first confirm , rapidly assess severity ,
exclude causes of severe hypertension for which
rapid decrease in BP will be harmful (ex – COA,head
trauma,intracranial mass lesion,sympathomemetric
drug overdose and severe pain) and prompt
initiation of antihypertensive therapy.

8. Preferably by using auscultation with careful attention to
cuff size and placement.
If manual BP measurement is not possible in emergency
situation automated BP readings can be substituted.

9.  Reliable method for obtaining frequent repeat BPs :
Intra arterial line , Oscillometric device

10. What Are The General Measures
We Should Take When Severe
Acute Hypertension Is Confirmed?
 Frequent BP and continuous cardiorespiratory
monitoring.
 Assessment of ABC and performance of ET intubation
in patients with depressed mental status , respiratory
failure or status epilepticus.
 Head Trauma(cervical spine immobilisation)
 Medications such as ketamine should be avoided
during rapid sequence.

11.  Two I.V. lines whenever possible (one for
antihypertensive medication and other for fluids)
 If seizures occur : lorazepam 0.05 – 0.1mg/kg until
seizures stop.

12. How Should We Manage Raised
BP?
 Hypertensive Emergency Goal: Lowering systolic BP in a
controlled fashion by no more than 25% of the overall planned
BP reduction over the first 8 hours of treatment.
 This is typically a BP between 95th and 99th percentiles for age ,
sex and height. But goal should be individualized for each patient
as determined by response to treatment.
 This goal can be accomplished by first administering 1-2
intravenous boluses of antihypertensive medications( ex –
labetalol 0.2 mg/kg/dose, hydralazine 0.2mg/kg/dose) followed
by continuous infusion of labetalol or nicardipine.
 Rapid lowering of BP by more than 25% of planned BP reduction
in the first 8 hours can cause irreversible target organ damage
such as permanent neurological sequelae, visual defects, MI and
renal insufficiency due to abnormalities of autoregulation
induced by chronic hypertension.

13.  The amount of time taken for further BP reduction
after initial 8 hours of therapy will depend upon
clinical setting and should be guided by an experienced
clinician such as paediatric nephrologist or intensivist.

14. Hypertensive Urgency Goal
 Immediate evaluation should be done
 When urgency arises from acute process with a rapid
change in mean arterial pressure (ex – PSGN),
intervention should occur promptly within hours and
treatment with I.V. anthypertensive medications is
appropriate.
 However in a setting of chronic condition (CKD), BP
can be lowered slowly and oral medications may be
used (ex – clonidine,isradipine)

15. Mode Of Administration
 Hypertensive emergencies : I.V.
 In general, start with lowest dose, adjust rate based
upon BP response.
 First Line I.V. Agents : Nicardipine and labetalol
(children and adolescents)
 Less frequent: Esmolol and phenoldapam
 Sodium nitroprusside : due to cyanide toxicity no
longer recommended as first line agent

16.  Children with volume overload may require diuretic
therapy.
 Ex – I.V. furosemide to maximize antihypertensive
effect but diuretics should never be used alone in such
patients.

17. DOSAGES
 Nicardipine: 0.5 – 1 mcg/kg/min, may be increased every
15-30 min, max 4-5 mcg/kg/min
 Labetalol :initial bolus 0.2-1 mg/kg, max. 40 mg followed by
an infusion of 0.25 – 3 mg/kg/hr
 Hydralazine: bolus dose of 0.2-0.6 mg/kg, max. 20mg, onset
of action is slower than nicardipine and labetolol but
duration is longer. A/E: Overshoot hypotension. Also useful
in preeclampsia.
 Phentolamine: Alpha adrenergic blocker, bolus of 0.1
mg/kg, max. 5 mg for treatment of sec. Htn caused by
excessive circulating catecholamines (eg:
Pheochromocytoma, cocaine or pseudoephedrine
overdose)

18.  Esmolol: Beta adrenergic blocker, 100-500 mcg/kg/min,
titrate every 10 min until desired effect or max. 1000
mcg/kg/min is reached. Rapid onset, short duration
 Fenoldopam: A peripheral dopamine receptor agonist.
Starting at 0.2 mcg/kg/min titrating every 15 min upto 0.8
mg/kg/min. Less potent than others and therefore not
routinely used as first line agent
 Enalaprilat: ACE inhibitor. Sometimes used in patients with
high renin states. A/E: prolonged hypotension and renal
insufficiency especially in neonates.
 Sodium nitroprusside: in selected patients. Eg: LVF.

19. ORAL AGENTS
 Clonidine: centrally acting alpha 2 adrenergic agonist. Reduces
BP by reducing cerebral sympathetic output. Rapid onset of
action with in 15-30 min. 0.05-0.1 mg/dose,repeated hourly upto
8 hours until desired BP is reached.
 Isradipine: Rapidly acting calcium channel bocker , reduces BP
with in one hour, peak effect in 2-3 hrs.0.05-0.1 mg/kg/dose. In
<2 yrs 0.03-0.05 mg/kg/dose
 Hydralazine: 0.25 mg/kg. onset 30 min to 2 hrs
 Minoxidil: Opens potassium channels in vascular smooth muscls,
causing potassium efflux that leads tohyperpolarisation and
relaxation. 0.1- 0.2 mg/kg/dose upto 1o mg/dose. Most potent
vasodilator and longest duration of action upto 8-12 hrs

20. On going hypertensive therapy
 Once control of severe HTN is achieved, diagnostic
evaluation and correction of any identifiable
underlying cause if possible.
 If IV infusion was used, gradually shift to oral drugs
 Of underlying cause cannot be corrected so that HTN
is abolished or if HTN persists, chronic therapy should
be continued

21. Specific Hypertensive emergencies
 Hypertensive encephalopathy : labetalol,nicardipine – continuous infusion
 Renal disease : children with acute kidney injury or underlying CKD and hypertensive
emergencies may require dialysis in addition to antihypertensive treatment depending on
degree of renal impairment. Drugs – labetalol, nicardipine, enalpril (very effective in view
of blockade of RAS , but renal insufficiency may be exacerbated). Since many patients with
renal disease and severe htn are overloaded with I.V. diuretics like furosemide 1-2mg/kg
initial bolus dose to a maximum of 40-80mg in patients with moderate renal insufficiency.
 Neonatal hypertension : nicardipine, labetalol(relatively contraindicated if BPD is
present),enalapril (avoided in neonates generally due to high renin state as it may cause
prolonged oliguria)
 COA : labetalol, esmolol,nicardipine
 Pre-eclampsia, eclampsia : delivery of the foetus prevents progression of maternal htn
and avids foetal complications, severe pre –eclampsia dictates pregnancy if pregnancy
>32wks, If<32 wks management at tertiary care. First line treatment – labetalol,
hydralazine is an alternative (risk of maternal hypotension), nicardipine.

22.  Cocaine or amphetamine overdose : lorazepam 1mg I.V.every 5 mins,
0.05mg/kg every 5 mins in children.
 Phentolamine: 0.1 mg/kg(max 5 mg)
 Patients with chest pain : sublingual nitroglycerine.
 Beta adrenergic blockers: contraindicated because they can cause unopposed
alpha adrenergic effects with exacerbation of HTN and MI.
 Phaeochromocytoma and paraganglioma: classic triad(headache, sweating,
tachycardia usually accompanied by HTN).Abdominal pain and back pain are
common. Primary treatment is surgical resection.Medical treatment is given
prior to surgical resection Ex- alpha adrenergic blockade with oral
phenoxybenzamine, doxazosin or prazosin as initial treatment. Addition of beta
blockade only after alpha blockade has been accomodated . Calcium channel
blockers or metyrosine can be used.

23. THANK
YOU FOR
PATIENCE