Bài giảng dành cho sinh viên y khoa, bác sĩ đa khoa, sau đại học. ĐH Y Dược TP Hồ Chí Minh. Definition Etiology Pathophysiology Clinical manifestation Diagnosis Management Prevention
CARDIOGENIC SHOCK Vu Minh Phuc MD PhD 04-2012 CONTENTS 04/14/20 Definition Etiology Pathophysiology Clinical manifestation Diagnosis Management Prevention DEFINITION Cardiogenic shock is a condition of inadequate tissue perfusion resulting from myocardial dysfunction The clinical definition of cardiogenic shock is decreased cardiac output and evidence of tissue hypoxia in the presence of adequate intravascular 04/14/20 ETIOLOGY (1) (2) (3) (4) (5) Congenital heart disease Myocarditis (virus, bacteria, sepsis, noninfectious inflammation) Poisoning or drug toxicity Myocardial injury (trauma, cardiac surgery) Cardiomyopathy – – inherited abnormality: DCM, HCM, RCM, NCCM acquired abnormality of pumping function • Myocardial ischemia or infarction • Secondary to valvular heart diseases (6) Acute valvular heart diseases: AR, MR, AS, prosthetic valve thrombosis (7) Arrhythmia (8) Obstruction: tamponade, contrictive pericarditis, myxoma (9) End stage of other kinds of shock 04/14/20 PATHOPHYSIOLOGY Preload variable Circulation volume CARDIOGENIC SHOCK Contractility decreased Afterload increased Cardiac output (CO) = Stroke Volume (SV) × Heart Rate (HR) cathecholamine 04/14/20 PATHOPHYSIOLOGY COMPENSATORY AND PATHOLOGIC MECHANISMS SVR (due to cathecholamine) → redirect blood flow from peripheral and splanchnic to the heart and brain HR and SVR → LV work & myocardial oxygen consumption SVR → SV when pumping function of the heart is poor 4 venous tone → CVP (right atrial) and pulmonary capillary pressure (left atrial) (5) Renal perfusion → activation of renin-angiotensin-aldosterol → renal fluid retention (4) + (5) Pulmonary edema 04/14/20 PATHOPHYSIOLOGY COMPENSATORY AND PATHOLOGIC MECHANISMS SV A B normal ventricular contractility A’ C C’ poor ventricular function SVR The relationship between stroke volume (SV) and systemic vascular resistance (RSV) 04/14/20 CLINICAL MANIFESTATIONS Findings consistent with cardiogenic shock Primary Assessment Findings A B C Assessment of Cardiovascular Function Assessment of End-Organ Funtion D 04/14/20E • Tachypnea • Increased respiratory effort (retractions, nasal flaring) resulting from pulmonary edema Tachycardia Normal or low BP with a narrow pulse pressure Weak or absent peripheral pulses Delayed capillary refill with cool extremities Signs of congestive heart failure (eg, pulmonary edema, hepatomegaly, jugular venous distention) • Cyanosis, low SpO2 (caused by cyanotic CHD or pulmonary edema) • Cold, pale, diaphoretic skin • Changes in mental status • Oliguria • • • • • • Changes in mental status • Variable temperature DIAGNOSIS Positive Diagnosis : presence of signs & symptoms of – – Shock and Heart failure Differential Diagnosis with other kinds of shock – Hypovolemic shock • Clinical picture of dehydration, bleeding or hemorrhage • Quiet tachypnea – Septic shock • Focal infection, hyper or hypothermia • Systemic Inflammation Reaction Syndrome (SIRS) 04/14/20 DIAGNOSIS Diagnosis of causes History, examination suggest Diagnostic tests Congenital heart disease ECG, CXR, Echocardiography Myocarditis (virus, bacteria, sepsis, noninfectious inflammation) Echocardigraphy, biopsy, Mac-Elisa, blood culture, immunologic tests Cardiomyopathy (DCM, HCM, RCM, NCCM), valvular diseases Echocardigraphy Myocardial ischemia or infarction ECG, Echo, cardiac isoenzymes, cardiac cath/angio, Arrhythmia ECG Tamponade, contrictive pericarditis, myxoma Echocardigraphy 04/14/20 10 DIAGNOSIS Assessment of End-Organ Function and complications – Hypoxemia and acidosis : Ionogram, arterial blood gas (ABG), central venous oxygen saturation, plasma lactate, hemoglobinemia – Kidney : urinary analysis, renal function – Liver : liver function, coagulation test, blood glucose – Heart : cardiac isoenzymes, ECG, echocardiogram 04/14/20 11 MANAGEMENT Main objectives To improve the effectiveness of cardiac function and overall cardiac output by increasing the efficiency of ventricular emptying To minimize interventions or host responses that increase metabolic demand Treatment Airway support To exclude the cause of cardiogenic shock Treatment of shock Treatment of complications 12 04/14/20 MANAGEMENT AIRWAY SUPPORT Monitoring of hypoxemia – – Continuously follow up SpO2 Central lines: CVP, arterial line, PA line (± ) → ABG, central venous oxygen saturation, PA pressure Airway support – – High flow oxygen is indicated NCPAP or BiPAP or ventilator : pulmonary edema 04/14/20 13 MANAGEMENT EXCLUDE THE CAUSES OF CARDIOGENIC SHOCK At the same time of treatment of shock – – – – – – CHD: specific procedures (BAS, balloon pulmonary valvar dilation, PGE1, ) Viral myocarditis : gamma globulin Bacterial myocarditis, sepsis : antibiotics Myocarditis in rheumatic diseases: corticosteroids Myocardial ischemia or infarction, poisoning or drug toxicity: specific treatments Treatment of other kinds of shocks Before treatment of shock Antiarrhythmia drugs (arrhythmia), pericardiocentesis (tamponade) After treatment of shock Cardiac surgery (CHD, valvular heart disease) 04/14/20 14 04/14/20 15 04/14/20 16 MANAGEMENT Preload variable TREATMENT OF SHOCK Fluid administration? Contractility decreased Inotropic agents? Afterload increased Reduce afterload? 04/14/20 17 MANAGEMENT TREATMENT OF SHOCK Fluid administration ∗ WHEN? • • • Presence of dehydration Presence of risk factors of inadequate preload: poor intake, fever, vomitting, diarrhea Low CVP, ventricle’s volume on echocardiogram ∗ HOW? and WHAT? • • • Cautiously and slowly give 5-10 mL/kg isotonic crystalloid infusion over 10-20 minutes Frequently assess respiratory function during fluid therapy → respiratory distress, pulmonary edema? NCPAP, BiPAP, ventilator are ready 18 04/14/20 MANAGEMENT TREATMENT OF SHOCK Inotropic agents DRUGS CLASS INOTROPE CHRONOTROPE LISITROPE SVR Dopamine Inotrope Vasoconstrictor ++ + (high dose) − (high dose) Dobutamine β1 > β2 > α Inotrope ++ + (high dose) − (high dose) Epinephrine β1 = β2 > α Inotrope Vasoconstrictor ++ + − (high dose) Norepinephrine β1 > α > β2 Vasoconstrictor + + − Milrinone (PD3 inhibitor) Inodilators + − + Nitroglycerin Nitroprusside Vasodilators − − − Vasopressin Vasoconstrictor − − − 04/14/20 venous tone 19 MANAGEMENT TREATMENT OF SHOCK Inotropic agents * WHAT KINDS? - Normal systolic BP = 90 + 2n (n = age) mmHg - Hypotension systolic BP < 70 + 2n ( < 90) mmHg - Fatal hypotension systoilc BP < 60 + 2n (< 70) mmHg Fatal hypotension → MOD → irreversible shock → die Inotrope agents has strong vasoconstriction (High dose Dopamine or Epinephrine or Norepinephrine) Hypotension Inotrope agents can SVR (Dobutamine or Milrinone + Dopamine –renal dose) Normal BP : Vasodilators (Nitroglycerin or Nitroprusside) 20 04/14/20 MANAGEMENT TREATMENT OF SHOCK Inotropic agents * WHAT KINDS? RV failure - preload is very important for RV’s compliance and contractility - volume infusion until systolic BP > 70 + 2n (>90) mmHg, CVP > 10 cm H20 - afterload # pulmonary arterial resistance - Milrinone, Dobutamine are preferred 21 04/14/20 MANAGEMENT TREATMENT OF SHOCK Inotropic agents * HOW TO USE? Fatal hypotension Inotrope agent has strong vasoconstriction - Epinephrine or - Norepinephrine Hypotension Inotrope agents can SVR - gradually then off Epi or Norepi - and Dobutamine or Milrinone - High dose Dopamine or (gradually the dose if no response) - and Dopamine-renal dose (gradually to renal dose) Stable hemodynamics Don’t change the drugs’ dose for ≥ 24 hours Stable hemodynamics Gradually drugs’ dose then off 22 MANAGEMENT TREATMENT OF COMPLICATIONS Adjust electrolyte and acid-base balance Acute renal failure Digestive hemorrhagia due to stress DIC Acute pulmonary edema associated with cardiogenic shock • Give diuresis even patient in shock • Morphine and Nitroglycerin are contraindicated 23 04/14/20 Thanks for your attention 04/14/20 24 ... or - Norepinephrine Hypotension Inotrope agents can SVR - gradually then off Epi or Norepi - and Dobutamine or Milrinone - High dose Dopamine or (gradually the dose if no response) - and... of – – Shock and Heart failure Differential Diagnosis with other kinds of shock – Hypovolemic shock • Clinical picture of dehydration, bleeding or hemorrhage • Quiet tachypnea – Septic shock •... 19 MANAGEMENT TREATMENT OF SHOCK Inotropic agents * WHAT KINDS? - Normal systolic BP = 90 + 2n (n = age) mmHg - Hypotension systolic BP < 70 + 2n ( < 90) mmHg - Fatal hypotension systoilc BP