Cardiac Case Based Emergencies

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Savithiri Ratnapalan, MBBS, M Ed, PhD© MRCP(UK), FRCP(C), FAAPHospital for Sick Children, University of Toronto, Canada

I do not have any relevant financial relationship with commercial interest to disclose.

Case Study 1: Crying non stop

• 10-month-old boy brought to ED for inconsolable crying

• He had a runny nose for 2 two days, no fever

• Decreased activity and crying since this morning

• Poor feeding today

Examination: Pale, breathing fast, crying

HR 280, RR 40/ min Wt 9KG , Cap. refill ~ 2 seconds, O2 98% RA

• Head/neck: No abnormalities• Heart: Tachycardia, no murmurs heard, all pulses felt• Lungs: Good air entry, child crying• Abdomen: Liver edge palpable RCM• Neuro: Crying, wants to be held by mom, Fontanelle level, pupils ERTL• Extremities: Cool upper and lower extremities

What exam information is missing?Temp 37.5 rectal

Monitor shows

Management Priorities: Rapid glucose 12 lead ECG, IV access…..

What is the diagnosis?

Supraventricular Tachycardia

Distinguishing SVT from ST

ST SVT

History Fever, sepsis, dehydration,

hemorrhage, hypovolemia,

precedes

Intermittent, paroxysmal

in onset

ECG ST rate is less than 2x normal

rate for age. Rate varies with

activity.

P waves present, normal

SVT rate at or greater

than 2x normal rate for

age. Minimal or no rate

change with activity.

P waves absent/abnormal

Management

• 100% oxygen NRB mask is placed

• Preparations are made to cardiovert as IV access is obtained

• Vagal maneuvers: Ice tried on face - no effect

• Adenosine 100 mcg/kg IV push is given followed by NS bolus (flush)

• ECG showed return of sinus rhythm

What to do if you cannot get an IV in the arm

• Pediatr Emerg Care. 2012 Jan;28(1):47-8• Adenosine from 0.05 to 0.25 mg/kg through IO in tibia followed by a saline flush• Three doses without resolution of the SVT

Pediatric Emerg Care 2017;33(1):47-8.

1. An intraosseous (IO) line in the patient's right tibia

2. Adenosine, 0.5 mg (0.1 mg/kg), diluted with N saline to a volume of 3 mL,

pushed rapidly through the IO line

3. Normal sinus rhythm was obtained seconds after the administration of the

adenosine

Sinus (ST):Rate: Infants <220/min

Children <180/min

Supraventricular (SVT):Rate: Infants ≥ 220/min

Children ≥ 180/min

Narrowcomplex

Good Perfusion:•CAB’s,O2

•Vagal maneuvers•Adenosine•Synchronized

cardioversion+sedation

Poor Perfusion:•CAB’s,O2

•Synchronized cardioversion

•± sedation

Too fast

TACHYARRHYTHMIAS (too fast)

Find the cause •Fever•Anxiety•Pain•Dehydration•Exercise

Case 2: 11-year-old with palpitations

• A 11-year-old girl was brought in with chest pain and palpitations. She had no fever or other symptoms and was not on any medication

• She looked okay but said she was scared. Pulse 180

• The nurse puts her on a cardiac monitor

ECG

Ventricular TachycardiaDrugs induced

Post cardiac surgery…

Wide

complex

Good Perfusion:•CAB’s,O2

•Rx – Adenosine•Amiodarone/Procainamide

•Synchronized Cardioversion•+ sedation

Poor Perfusion:•CAB’s,O2

•Synchronized Cardioversion

•± sedation

Too fastTACHYARRHYTHMIAS

Supraventricular Tachycardia1.Bundle branch block2. Atrio-Ventricular Reentry Tachycardia

AVRT with an Accessary pathway

Etiology of tachycardia in an ill-appearing child

Cardiac conditions

SVTVTTorsades de Pointes

( Rx Magnesium sulphate)

Hypertrophic cardiomyopathyMyocarditisCardiac tamponade

Non-cardiac conditions

HypoglycemiaHypovolemic shockSepsisAnaphylaxisTox exposureCatastrophic illness:

CNS, GI, trauma (abuse)Metabolic diseaseHyperthyroidism

Tachycardia• Clinical features can be varied:

• Palpitations in verbal children

• Shock in any age

• Generalized symptoms of malaise and weakness

• Diagnostic studies:

• Cardiac monitor, ECG, sepsis evaluation if young infant has signs and symptoms suggestive of infection

• CXR, echocardiogram

• Management: ABCs, stabilize

POSSIBLE REVERSIBLE CAUSES

H’s T’s

Hypoxia Toxins (overdose)

Hypovolemia Trauma (esp. non-accidental)

H+ (acidosis) Tension pneumothorax

Hypo/hyperkalemia Tamponade (cardiac)

Hypo/hyperglycemia Thrombus (MI)

Hypo/hyperthermia Thrombus (PE)

Management: Dysrhythmias

Narrow complex (SVT)

• Vagal maneuvers

• Adenosine: 100 mcg/kg bolus, increase as necessary: 200 mcg/kg

• Cardioversion unstable SVT

Wide complex

• Try adenosine

• Amiodarone or

• Procainamide

• Cardiology consultation

Feel for the pulse: If present and child stableget baseline ECG.

Obtain vascular access

ELECTRICAL THERAPY

Defibrillation• Ventricular Fibrillation or • Ventricular Tachycardia with NO PULSE ONLY

Synchronized cardioversion• Tachycardias WITH A PULSE ONLY• Unstable (poor perfusion) – immediately• Stable (good perfusion) – if meds don’t work

BEWARE ALL OTHER RHYTHMS ARE UNSHOCKABLE!

Pulseless electrical activity PEA / Asystole

•CAB’s•CPR•Rx – Epinephrine

Specific Tx:H’s & T’s

CARDIAC ARREST RHYTHMS

Ventricular fibrillationVentricular tachycardia

without a pulse

•CAB’S•CPR immediately•Defibrillate immediately•Rx – Epinephrine,

Amiodarone

Case 2: Unresponsive Episodes

• 3-year-old girl passed out eating cereal; awoke after 5 min.

• She was stiff with eyes rolled back ~ approx. 5 min.

• Minimal period of sleepiness, now awake and alert; no retractions; skin color is normal

Initial Assessment and Focused History

• Normal appearance, normal breathing, normal circulation

ABCDEs: Normal• Vital signs: HR 120; RR 24; BP 80/60; T 37.7 C Wt 12 kg; O2 sat 99%

Focused History:

• Three similar episodes; two associated with “temper tantrums”

• PMH and FH: Negative

Cause: Heart, Brain or Breath Holding?

• Loss of consciousness

• Lasted only a few minutes

• No postictal state

• No evidence of seizure activity: Urinary incontinence, bitten tongue, witnessed tonic-clonic activity

Diagnostic Studies

• ECG

• Laboratory • Glucose

• VBG, Electrolytes, Ca++, Mg++, PO4

• CBC with differential

Markedly Prolonged QT Interval

T-wave alternans

12 Lead ECG

Prolonged QT

• 10% present with seizures

• 15% of patients with prolonged QTc die during their first episode of arrhythmia

• 30% of these deaths occur during the first year of life

Case Progression

• This patient has prolonged QT syndrome

• She is at risk for fatal dysrhythmia (ventricular tachycardia or ventricular fibrillation)

• She needs to be admitted/transferred to a pediatric cardiology center for cardiology evaluation

Prolonged QTc Causes

• Drugs

• Antimicrobials (Erythromycin, Clarithro, Azithro, Levofloxacin, Ciproflox, Septra, Antifungals (Fluconazole)

• Antipsychotics (Amitriptyline, Desipramine, Imipramine, Sertraline)

• Sedatives (Chloral hydrate)

• Antihistamines: Terfenadine, astemazole

• Other: Cisapride, pentamidine, phenytoin, organophosphates, liquid protein diet, some herbal preparations

• Electrolyte Issues: Low K, Ca or Mg (Hypokalemia, Hypocalcemia, Hypomagnesemia)

• Congenital Long QT Syndromes: Jervell and Lange-Nielsen, Romano-Ward,…

• Others: Hypothermia, Cardiac ischemia, Increased ICP

Cardiac Causes of Syncope

• Hypertrophic cardiomyopathy• Syncope with exercise• At risk for sudden death; positive family history• Non-specific murmur; ECG can show non-specific findings• CXR is non-diagnostic• Echocardiogram is diagnostic

• Chronic cardiomyopathy• Chronic CHF

• Dysrhythmias

Cardiac Syncope

• Consider cardiac arrhythmias in children presenting with brief, nonspecific changes in level of consciousness:

• Fainting, syncope, seizures, breath-holding, apparent life-threatening events

• Family history: sudden, unexplained deaths prior to 55, faintingepisodes, deafness, epilepsy, drowning or unexplained accidents

• Episodes associated with exercise are particularly concerning • Patient instructed not to exercise until cleared by a cardiologist

The Bottom Line

• Always check the pulse first

• Dysrhythmias: Management dependent on the state of perfusion

• Sinus tachycardia is not an arrhythmia but check for the cause

• Provide ventilation and oxygenation for all patients in

cardiopulmonary arrest, as the primary etiology is often

respiratory failure