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Hypertension in Children (Hypertensive Emergency)
Dr. R Ramesh KumarMD, DNB, FPCC, DM (Ped Crit Care), MNAMSAssistant ProfessorPediatric Critical Care UnitsDepartment of pediatricsJIPMER, Puducherry 605 006
Overview
• Case based discussion
• Work-up
• Initial management and algorithm
Pre-hospital h/o
S y m p t o m a t I c1 2 3 4 5 6 m o n t h s
Developmentally normalImmunized for ageFirst episode of major illnessNo family h/o of similar illness
Abdominal pain - 6monthsPeri-umbilical & left upper regionColicky, intermittent. Constipation
Head ache - 6monthsFrontal region, throbbing naturealternate with pain abdomenrelieved with medication
Worsening symptoms 2monthsBlurring of visionPoor appetite and loss of weight(5kgs)Polyuria and Polydipsia
Admitted for 18days144 / 96 mmHg
Ref to Higher Centre
Pediatric Emergency:
AppearanceNormal / Abnormal
Work of breathingNormal / Increased / decreased
Skin circulationNormal / Abnormal
Stable : Non-Life threatening
Primary Assessment (ABCDE): Assessment Pentagon
Airway:Open & stable
Breathing:RR 26/minEfforts: NormalAir entry: NormalAuscultation: NoneSpO2 (room air) :100%
Circulation:HR : 100/minCFT : 2 SecBP : 140/104 mmHg (116)Central pulse: GoodPeripheral pulse: GoodSkin temp: CoolRhythm: Regular
Disability:GCS 15/15Pupils –3mm RLActivity: Normal & symmetricalBlood sugar : 156mg/dl
Exposure: Temp: 37 CColour: NormalSurface finding: - - -
Pediatric emergency:
Final physiological impression
Stable
Respiratory Distress
Respiratory Failure
Compensated Shock
Hypotensive Shock
Cardiopulmonary failure
Primary brain/systemic dysfunction
Triage classification
Level 1 (resuscitation)
Level 2 (emergent)
Level 3 (urgent)
Level 4 (less urgent)
Level 5 (non-urgent)
Immediate concern
• Is it hypertension ? { definition }
• Is it hypertensive crisis ? { classify }
• End organ damage ? { asses the severity }
• Immediate goal of the Rx ? { target of therapy }
Investigations ? { underlying cause }
Immediate concern : Is it hypertension ? { definition }
Task Force on High Blood Pressure in Children and Adolescents(The fourth report). Pediatrics 2004.
• systolic blood pressure (SBP) and/or diastolic blood pressure(DBP) ≥ 95th percentile for age, height, and sex on repeatedmeasurement.
based on severity-
• stage I
between the 95th and 99th percentile plus 5mmHg.
• stage II
blood pressure >99th percentile plus 5mmHg.
Immediate concern : Is it hypertension ? { definition }
ESH/ESC guidelines 2007. J Hypertens 2009.
• term prehypertension has been changed to ‘high-normal’.
• ≥ 90th to ≤ 95th
• ≥ 120/80 even if below 90th percentile in adolescents.
• patient age =10yrs, height = 140cms, sex=male.
MABP = 101 mmHg
Immediate concern : Is it hypertensive crisis ? { classify }
• hypertensive emergencies
• hypertensive urgencies
• they exceed stage II hypertension in severity.
• require prompt pharmacologic intervention .
• however, they differ based upon clinical presentation.▫ with symptomatic end-organ dysfunction --> emergencies
▫ without symptomatic end-organ dysfunction -- > urgencies
• whether both definitions are absolutely necessary ? ? ?▫ both diagnoses require emergent therapy.
- Pediatr Nephrol 2009 - Pediatr Drugs 2011
hypertensive crises
Immediate concern : Is it hypertensive crisis ? { classify }
CNS :
GCS 15/15
Pupil –3 mm RL
Tone – N
DTR- N
Plantar : flexor
Meningeal signs: -ve
No focal deficits
Funds- papilloedema
with hypertensive
retinopathy (Grade - IV)
CVS:
S1 S2
apex at 5th ICS -MCL
soft systolic murmur present in
left parasternal area (AA)
RS :
NVBS
No added sound
P/A:
No tenderness, lump, bruit
Soft , BS+
Wt: 23kgs L- 140cms
hypertensive emergencies
Immediate concern: End organ damage? { asses the severity }
• the presentation depends on▫ underlying medical conditions▫ baseline systemic BP▫ rate of rise and degree of BP elevation▫ effects on end organs
• common Sequelae of End-Organ Damage▫ Encephalopathy▫ Acute left ventricular failure▫ Myocardial infarction & Unstable angina▫ Pulmonary edema▫ Eclampsia▫ Stroke & Head trauma▫ Life-threatening bleeding▫ Aortic dissection
Immediate concern: End organ damage? { asses the severity }
• on physical exam: findings of accelerated hypertension(papilledema, CCF, pulmonary edema)
• usually only seen in hypertensive emergencies.- Pediatr Nephrol 2009
• retinopathy : pattern of lesion related to the onset.- Clin Pediatr (Phila) 2009
• recent significant increases in BP▫ focal arteriolar narrowing & retinal hemorrhages
▫ Microaneurysms & cotton-wool spots
• long-standing systemic HTN▫ generalized arteriolar narrowing & arteriovenous nicking
-N Engl J Med 2004
Grade 1Generalised arteriolar constriction - seen as `silver wiring` and Vascular tortuosities.Grade 2+ irregularly located, tight constrictions - `AV nicking` or `AV Nipping`Grade 3+ with cotton wool spots and flame-haemorrhagesGrade 4+ with swelling of the optic disk (papillodema)
only 8.6% had evidence of retinopathy diagnosed with an ophthalmoscope
Immediate concern : End organ damage?{ asses the severity }
• strongest link between HTN and retinal changes with theirrelationship with stroke risk.
• retinal blood flow shares embryologic, anatomic, andphysiologic attributes with the cerebral circulation.
• left ventricular hypertrophy (LVH)
• correlation is lower when casual BP measurements are used.
• occurs more frequently in Hispanic and African American.
• eight percent experienced CCF with pulmonary edema.
- Pediatrics 2004 - J Pediatr 2008
Immediate concern : End organ damage?{ asses the severity }
• evidence of renal damage
• the degree of proteinuria can be correlated with the severity.
• Clinically, elevated sr creatinine and BUN levels
▫ segmental glomerular fibrinoid necrosis.
▫ prominent fibrinoid necrosis of afferent and efferent arterioles.-Arch Pathol Lab Med 2007
Immediate concern : Immediate goal of the Rx ? { target of therapy }
• Task Force on High Blood Pressure in Children andAdolescents (The fourth report). Pediatrics 2004.
• controlled antihypertensive therapy
• gradual BP decrease of ≤ 25% within the first 8 hours.
• deliberate and gradual lowering of over the next 40 hours.
• 25% first 8–12 h, 25% next 8–12 h, final 50% 24 h after that.- AIIMS protocal -Pediatr Nephrol (2009)
• MABP should be lowered no > 25% within the first hour.
Immediate concern : Immediate goal of the Rx ? { target of therapy }
• Task Force on High Blood Pressure in Children andAdolescents (The fourth report). Pediatrics 2004.
• controlled antihypertensive therapy
• Final targets
• BP ≤ 90th percentile for sex, age, and height
if end-organ damage or underlying co-morbidities such diabetes.
• All other should have their BP decreased to ≤ 95th percentile.
Immediate concern : Immediate goal of the Rx ? { target of therapy }
• autoregulation of cerebral blood flow
• autoregulation of renal blood flow
Initial management
• i.v NTG 0.25 to 0.35 µg /kg /min
target MABP 1st 8hours not < 75mmHgat 48hours 93mmHg
85
90
95
100
105
110
115
1 2 3 4 5 6 7 8 9
MA
BP
mm
Hg
Time in hour
• Proparanlol 3.8 mg /kg/ day ÷2doses
• Prazocin 277 µg /kg / day ÷4 doses
• Phenoxybenzamine 4.7 mg /kg/day ÷ 3doses
Resistant Arterial Hypertension
• defined as BP above the target range set by current guidelines despite the concurrent use of ≥ 3 antihypertensive drugs of different classes, including a diuretic, at their maximum or highest tolerated doses.
• primary aldosteronism, pheochromocytoma & Cushing's syn.• acromegaly, hyper or hypothyroidism, hyperparathyroidism and
mineralocorticoid hypertension (e.g. apparent mineralocorticoid excess, Liddle's syndrome).
• first step in evaluation is to exclude other secondary causes, particularly renal disorders.
Endocrine hypertension
- European Journal of Internal Medicine 2011
Causes of Hypertension
Mechanism of Hypertensive crisis
Investigations – Initial
• Complete blood count
• Basic metabolic panel including magnesium and phosphate
• Serum uric acid
• Fasting lipid profile
• Fasting blood glucose
• Urine analysis/culture
• Urine electrolytes, creatinine, protein
• Chest X-ray
• EKG and echocardiogram
• Renal ultrasound with doppler
Investigations ?
For end-organ damage For underlying cause
- Fundus- Neuroimaging - Carotid doppler- CXR- 12 lead ECG- ECHO- USG abdomen- Urine R/E & C/S- Hemogram
- Angiography - Nuclear scan- Hormonal study- Lipid profile
Initial investigations
• SERFTSr.Na 144, K- 4.5, Urea- 19, Cr-0.4
• Hemogram Hb-9.7, TLC-9400 (56,44,5,2),platelets- 7.85lakhs, PS-normal
• USG abdomen• Urine analysis - normal
• CXR (CT ratio 53%)
• ECG
• ECHOMild LVH and mild LV dysfunction (EF 42%)
• CPK-MB- 69U/L• CT Chest -angio
Biochemical Diagnosis of Pheochromocytoma
• Epinephrine 4.16 (<8.66)
1.69 µg / g creat (1-15)
• Nor epinephrine 147.58 (5-50)
414.57 µg / g creat (20-73)
• Dpamine 1363.84(51-474)
3831µg / g creat (164-749)
• VMA- random -HPLC 62.55 µg / g creat (1.5-5.1)
(72hours before: tea, coffee, banana, vanilla, chocolate )
Catecholamine Producing Tumors
Neural Crest
Sympathoadrenal Progenitor Cell(Neuroblasts)
Chromaffin Cell Sympathetic Ganglion Cell
Intra-adrenal Extra-adrenalPheochromocytoma
Ganglioneuroma
Neuroblastoma
Catecholamine synthesis and metabolism & Tumor Secretion
• Large Pheo: more metabolites
(metabolized within tumor before release)
• Small Pheo: more catecholamines
• Sporadic Pheo: Norepi > Epi
• Familial Pheo: Epi > Norepi
• Malignant Pheo: Dopamine, HVA
• Paraganglioma: Norepi
• Cheodectoma, glomus jugulare: Norepi
• Gangioneuroma: Norepi
• Neuroblastoma: Dopamine, HVA
{ left side }
Size cut-off - ≥ 8cms ≤
{ right side }
Urine catecholamines in paediatrics
Do I need to do 24 h collection or is a single, spot sample good enough?
• a 24 h collection on an infant or young child is difficult.
• diurnal variation in metabolite excretion.(well documented in the setting of phaeochromocytoma)
• negative spot samples are also negative on 24 h collections.
Clinical bottom line
• Untimed (random or spot), urine collection methods are as effective as 24 h collections and far more practical.
- Arch Dis Child Educ Pract Ed (2011)
Patient – random – urine sample – HPLC - positive
Urine catecholamines in paediatrics
Can I use the test to rule out phaeochromocytoma?
• higher index of suspicion is warranted.
• triad of hypertension, sweating and tremors.
• in practice, it is almost never the cause of isolated HTN.
• sensitivity of 86% and specificity of 88%.
Clinical bottom line
• Without strong clinical suspicion, urine catecholamine testing does not provide useful diagnostic information.
- Arch Dis Child Educ Pract Ed (2011)
Biochemical Diagnosis : Which Test Is Best?
• Sensitivitiesplasma free metanephrines 99% [95% CI,96%-100%]
urinary fractionated metanephrines 97% [95% CI, 92%-99%]
• Specificityurinary vanillylmandelic acid 95% [95% CI, 93%-97%]
urinary total metanephrines 93% [95% CI, 89%-97%]
plasma free metanephrines 89% [95% CI, 87%-92%]
urinary catecholamines 88% [95% CI, 85%-91%]
plasma catecholamines 81% [95% CI, 78%-84%]
urinary fractionated metanephrines 69% [95% CI, 64%-72%]
• Combinatin tests did not improve the diagnostic yield.Clinical bottom linePlasma free metanephrines provide the best test for excluding or confirming pheo
Should be the test of first choice for diagnosis of the tumor. -JAMA. 2002
Phaeochromocytoma in children - Review
• thought to be responsible for ,1% of childhood hypertension.
• benign - 0.11 & malignant - 0.02 per million.
Functioning
PhaeochromocytomasExtraadrenal sympathetic
paragangliomas
Non-functioning
Parasympatheticparagangliomas
of head and neck
-Arch Dis Child (2008)
Phaeochromocytoma in children - Review
• more common in older children.
• male preponderance in childhood. (female reproductive yr).
• overall equal sex incidence.
rule of 10
• 10% extra-adrenal (closer to 15%)
• 10% occur in children
• 10% familial (59% - 70%)
• 10% bilateral or multiple (more if familial)
• 10% recur (12% more if extra-adrenal)
• 10% malignant
• 10% discovered incidentally
Plan for definitive producer: Step -1 Localisation of tumour
• Successful management depends on- high-quality imaging to accurately localize the tumor and stage
the extent of disease.
• The choice of imaging modality depends on - the level of suspicion determined by biochemical evidence,
- previous history of a phaeochromocytoma
- inherited predisposition
• Ultrasound - initial investigation in those who are symptomatic.
• abdominal MRI or CT scan
• whole-body metaiodobenzylguanidine (MIBG)
Plan for definitive producer: Step -1 Localisation of tumour
• spiral CT: - high sensitivity (93% and 100% for adrenal gland and 90% for
extra-adrenal disease- Lesions 0.5 cm or larger can routinely be detected- iodinated contrast is related to hypertensive crises
• MRI- sensitivity 90% for extra-adrenal disease- absence of fat in pheochromocytomas (ct. benign adenomas)- superior to CT in the assessment of the relationship between the
tumor and the surrounding vessels.
• they lack specificity.
-Hematol Oncol Clin N Am (2007)
Plan for definitive producer: Step -1 Localisation of tumour
• 123 (131) -I-MIBG scintigraphy
- may lack sensitivity (80–90%), but high specificity (98%).- it is a physiologic and not anatomic study.- False negative scan
- Labetalol, reserpine, TCAs, phenothiazines (stop 4-6 wk prior)
• 111-Indium-penotreotide (somatostatin receptors)• 18F-fluorodeoxyglucose (FDG) & 6-[18F]-fluorodopamine
• Benign vs malignant (invasion of adjacent organs or metastatic disease)
• no single investigation can reliably predict malignancy before surgery.
Plan for definitive producer: Step -2 pharmacologic blockade
• manipulation of tumor can cause massive outpouring catech- hypertensive crisis, stroke,
- arrhythmias, myocardial infarction
• Before the introduction of adrenergic blockade- surgical mortality rates ranged from 24% to 50%.
• Extended release prazosin (4 times/day)- provides round the clock control of blood pressure.
- very effective in controlling paroxysms and adequate α blockade.
-HK Ganesh et al ,Indian J Pediatr 2009
• Kocak et al found that prazosin given in 3-4 divided doses- much more effective in BP control than a single daily dose.
- Int Surg 2002Normal targeted BP or development of orthostatic hypotension
Plan for definitive producer: Step -2 pharmacologic blockade
Target 90th centile
Achieved 90-95th centile
Phenoxy
Pr
az
os
in
Prazosin
Phenoxy
Ph
en
ox
y
Propranolol
liberal salt and fluid intake
Plan for definitive producer: Step -3 Pre-operative plan
• BP control 90-95th centile
• Pre-anasethetic order
• N.P.O & i.v fluid (100%)
• Stop phenoxybenzamine dose
• Shift to O.T at 6am
• Anticipated complication
• intraoperative hypertension --- hypotension
• postoperative ventilation & hypotension
• electrolyte abnormality
Plan for definitive producer: Step -4 operative & post-op
• 14 huors in O.T ( bilateral adrenalectomy)-inherited pheochromocytoma, cortical-sparing adrenalectomy
• triple-lumen IJV, intra-arterial line.
• GA & epidural (induced with thiopentone ---- fentanyl,lignocaine, vecur)
• After clamping of adrenal vessel hydrocortisone was given.
• 4 liter of fluid (colloid , crystalloids )
• Dopamine, NE, epi, dobutamine
• Shifted to PICU at 8 pm
• P-SIMV for 6hours--- spont 2hours– extubated---n-CPAP
In O.T
Plan for definitive producer: Step -4 post-op
• Sedo-analgesia (midazolam, fentanyl).
• Ceftriaxone, amikacine – 5days.
• N.P.O for 7days
• MABP 90-95th centile
• Vasoactive therapy gradually trapped off over 48hours.
• Electrolytes and RBS - Sr.Na:140----147---144---137---142---137-----131----137
- Sr.K: 4.8----3.2----4.7----3.6----3.4-----3.5-----3.4-----4.7
- RBS:107----132---85----131---151----118----125---120
• Hydrocortisone 100mg/m2/d-48hrs - tapered to 20mg/m2/day.
Proposed algorithm for the management of hypertensive crisis
Medication
Follow-up plan
• lifelong steroid hormone replacement therapy.- risk of acute adrenal insufficiency(25% to 33%).
-Hematol Oncol Clin N Am (2007)
• 1st urinary catecholamines after 1 – 2 w.
• initial - 6-monthly measurement of BP and urinary catecholamines.
• if a second or recurrent phaeochromocytoma is identified- investigation is as for the initial presentation.
- ture recurrence 12%.
• annual follow-up for life-long.
r e c a p • Contrary to traditional teaching
an identifiable germline mutation in up to 59% - 70%.
• Endocrine hypertensionprimary aldosteronism, pheochromocytoma & Cushing's syndrome.
to exclude other secondary causes, particularly renal disorders.
• Random urine collection are as effective as 24 h sample.British Society of Paediatric Endocrinology and Diabetes
raised 24 h urinary metanephrines and catecholamines on twooccasions.
• Preoperative preparation is essentialpharmacologic blockade of catecholamine
thank you