Cardiovascular System II

1. Cardiovascular System II

2. Objectives • Present the clinical features and emergency management of cardiovascular disorders, including: • Diagnose and treat rhythm disturbances. • Detect and treat cardiomyopathy. • Treat shock. • Create differential diagnosis and management plan for syncope.

3. Case Study 1: “Not Breathing” • 10-day-old boy brought to ED for not breathing and color change. • 3 weeks premature, discharged from hospital 3 days ago with apnea monitor • Decreased activity since discharge • Poor feeding today

4. Initial Assessment (1 of 2) PAT: • Abnormal appearance, abnormal breathing, abnormal circulation Vital signs: • HR 220, RR 14, BP 55/36, Wt 3.5 kg (birth weight 3.7 kg), O2 sat 88% on room air

5. Initial Assessment (2 of 2) A: Patent without evidence of obstruction B: Nonlabored but diminished respiratory rate C: Mottled, cool, distal cyanosis, tachycardic and weak pulse D: Weak cry, nonfocal exam E: Normothermic, no evidence of trauma, fontanel flat

6. Detailed Physical Exam • Head/Neck: No abnormalities • Heart: Tachycardia, no murmurs heard • Lungs: Decreased breath sounds • Abdomen: Liver 2 finger breadths below RCM • Neuro: Weak cry, lethargic, poor interaction, responsive to pain and contact • Extremities: Cyanotic, cool upper and lower extremities

7. Question What is your general impression of this patient?

8. General Impression • Cardiopulmonary failure • Lethargic but responsive, inadequate respirations and tachycardia; mottling with distal cyanosis What are your initial management priorities?

9. Management Priorities • ABCs • Open airway. • Give 100% O2 by BMV, or perform endotracheal intubation. • Check rhythm on cardiac monitor. • Obtain vascular access. • Obtain blood glucose prn. • Check rectal temperature.

10. Case Discussion (1 of 2) • Tachyarrhythmias: • Wide complex • Ventricular tachycardia • Supraventricular tachycardia (SVT) with aberrancy • Narrow complex • Sinus tachycardia • SVT

11. Case Discussion (2 of 2) • 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 who has signs and symptoms suggestive of infection • CXR, echocardiogram • Management: ABCs, stabilize

12. Background: Dysrhythmias • 3 basic types: • Fast pulse (tachyarrhythmia) • Slow pulse (bradyarrhythmia) • Absent pulse (pulseless) • Dysrhythmias may impair cardiac function, leading to cardiac arrest. • Occult dysrhythmias (e.g., prolonged QT syndrome, WPW syndrome)

13. Clinical Features: Your First Clue • Intermittent, paroxysmal presence of symptoms • Sudden onset of symptoms with little or no prodrome • Presentation of dysrhythmias can range from stable to cardiopulmonary arrest.

14. Distinguishing SVT from ST

15. Supraventricular Tachycardia

16. Diagnostic Studies • Radiology: • CXR important to look for signs of: • Structural congenital heart disease • Congestive heart failure (prolonged dysrhythmia) • Signs of infection (pneumonia) • Laboratory: • ALWAYS check blood glucose to exclude hypoglycemia in any child with abnormal mental status.

17. Differential Diagnosis: What Else? • Hypoglycemia • Sepsis • Hyperthyroidism • Volume depletion • Catastrophic illness: • CNS, GI, trauma (abuse) • Metabolic disease

18. Management: Dysrhythmias • ABCs • Get baseline ECG. • Obtain vascular access. • For SVT (see AHA algorithm): • Vagal maneuvers • Adenosine: 100 mcg/kg bolus, increase as necessary: 200 mcg/kg • Cardioversion for unstable SVT • Procainamide or amiodarone if QRS is wide • Digoxin to slow rate if cardioversion unsuccessful • Cardiology consultation

19. Tachycardia Management

20. The Bottom Line: Dysrhythmias • Management is driven by presence or absence of poor perfusion. • Sinus tachycardia is not an arrhythmia but its etiology must be determined. • Provide ventilation and oxygenation for all patients in cardiopulmonary arrest, as the primary etiology is often respiratory failure.

21. Other Considerations (1 of 2) • Interface with EMS/Transport: • Transport issues: Case such as this should be transported to pediatric referral center after stabilization. • ALS transport with monitoring and IV access • Treatment plan for possible en route for recurrence – including potential for cardioversion • Consult accepting pediatric cardiologist

22. Other Considerations (2 of 2) • Documentation: • Always try to get baseline 12-lead ECG before and after cardioversion. • Treatment record from prehospital and ED care • EMTALA compliance • Risk management: • Always check blood glucose. • Assure rapid triage of infants in distress. • Do not hesitate to cardiovert when child is unstable.

23. Reversible Non-Cardiac Causes of Dysrhythmias • Four H’s: • Hypoxemia • Hypovolemia • Hypothermia • Hyper/Hypokalemia and metabolic disorders • Four T’s: • Tamponade (cardiac) • Tension pneumothorax • Toxins/poisons/ drugs • Thromboembolism

24. Case Progression/Outcome • ECG reveals SVT. • Infant receives BMV ventilation. • Preparations are made to cardiovert as IV access is obtained. • Adenosine 100 mcg/kg IV push is given followed by NS bolus (flush). • ECG shows return of sinus rhythm. • BMV is discontinued as infant’s condition stabilized. 100% oxygen NRB mask is placed.

25. Case Study 2:“Unresponsive Episodes” • 2-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

26. Initial Assessment and Focused History PAT: • 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

27. Question What is your general impression of this patient?

28. General Impression • Stable • Patient with syncope • In no distress; normal exam • Concerning/ominous history What are your initial management priorities?

29. Case Discussion • Syncope in young children is a serious symptom. • Must attempt to exclude life-threatening causes • Differential diagnosis is critical: • Seizure • Cardiac • Breath-holding spell

30. Clinical Features: Your First Clue • Loss of consciousness • Lasted only a few minutes • Minimal or no postictal state • No stigmata of seizure: Urinary incontinence, bitten tongue, witnessed tonic-clonic activity

31. Diagnostic Studies • Radiology: • CXR offers little. • CT or MRI may be indicated if considering seizures. • Laboratory is often normal but may include: • Electrolytes • CBC with differential • Ca++, Mg++, PO4

32. T-wave alternans Markedly Prolonged QT Interval

33. 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.

34. What Else?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

35. Critical Concepts (1 of 2) • Consider cardiac arrhythmias in all patients presenting with brief, nonspecific changes in level of consciousness: • Fainting, syncope, seizures, breath-holding, apparent life-threatening events

36. Critical Concepts (2 of 2) • Family history may be positive for sudden, unexplained deaths prior to 55, fainting episodes, or unexplained accidents. • Episodes associated with exercise are particularly concerning. • Patient instructed not to exercise until cleared by a cardiologist.

37. Pulseless Arrest* VF/VT Not VF/VT Shock x 3 Vasopressor Vasopressor (Drug - Shock) CPR x 3 min Shock *CPR and seek reversible causes throughout Anti-arrhythmic

38. 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.

39. Case Outcome • This child is hospitalized. • Monitored and confirmed to be at risk for dangerous dysrhythmia • Discharged on medications shown to decrease her risk of VT/VF (e.g., ß blockers) • She is a candidate to receive an AICD when she gets older.

40. Case Study 3: “Chicken Pox” • 6-month-old with chicken pox lesions that began 3 days ago. Lesions are spreading. More scabs today. • Fever since yesterday, higher today. • Today, his skin appears to be red. • He is fussy and not feeding well.

41. Initial Assessment (1 of 2) PAT: • Normal/abnormal appearance, normal breathing, normal circulation Vital signs: • HR 160, RR 40, BP 79/56, T 39°C, Wt 8.1 kg, O2 sat 98% on room air

42. Initial Assessment (2 of 2) A: Patent without evidence of obstruction B: Normal C: Generalized red erythroderma, warm, tachycardic (febrile) D: Nonfocal exam, irritable E: Many impetiginous scabs, pustules and vesicles; some with surrounding cellulitis

43. Detailed Physical Exam • Head/Neck: No abnormalities except for skin • Heart: Tachycardic, no murmurs heard • Lungs: Clear breath sounds • Abdomen: Normal except for skin • Neuro: Alert, subdued, no meningismus • Skin: Many vesicles, scabs, pustules; some with surrounding cellulitis. Generalized warm erythroderma. Capillary refill 2 seconds.

44. Question What is your general impression of this patient?

45. General Impression • Compensated shock • Tachycardia and mild change in appearance (fussy) • Possible septic shock as varicella lesions with signs of secondary infection (Staph aureus, group A strep) • Erythroderma: Scarlet fever versus toxic shock What are your initial management priorities?

46. Management Priorities • Provide supplemental oxygen. • Obtain vascular access. • Determine rapid glucose. • Begin fluid resuscitation at 20 mL/kg – 160 mL NS. • CBC, blood culture, other optional labs • IV antibiotics • Repeated assessment for signs of shock

47. Shock • Inadequate tissue perfusion (delivery of oxygen and nutrients) to meet the metabolic demands of the body. • Hypovolemic • Cardiogenic • Distributive • Septic

48. Background: Shock • Compensated: • Vital organs continue to be perfused by compensatory mechanisms. • Blood pressure is normal. • Decompensated: • Compensatory mechanisms are overwhelmed and inadequate. • Hypotension, high mortality risk • Aggressive treatment of early shock: • Halts progression to decompensated shock

49. Clinical Features: Your First Clue • Apnea, tachypnea, respiratory distress • Skin: Pale, cool, delayed capillary refill. Warm shock will appear normal. • Lethargic, weak, orthostatic weakness • Tachycardia, hypotension • Specific types of shock: • Neurologic deficits (spinal cord injury) • Urticaria, allergen trigger, wheezing • Petechiae, erythroderma

50. Hypovolemic Shock • Fluid loss: • Diarrhea, vomiting, anorexia, diuresis • Hemorrhage • Resuscitation: • Fluid replacement • NS or LR 20 mL/kg bolus infusions, reassess, repeat as needed • Blood transfusion for excessive hemorrhage