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  1. Inotropes & Vasopressors Dr.M.Elakiya
  2. Definitions Inotropes: Agents administered to increase myocardial contractility and therefore cardiac index Vasopressor Agents are administered to increase vascular tone and thereby elevate mean arterial pressure (MAP).
  3. Inotropes Vs. Vasopressors
  4. Inotropes • Drugs that affect the force of contraction of myocardial muscle • Positive or negative • Term “inotrope” generally used to describe positive effect
  5. Vasopressor • Drugs that stimulates smooth muscle contraction of the capillaries & arteries • Cause vasoconstriction & a consequent rise in blood pressure
  6. Main Goal Tissue perfusion & oxygenation
  7. Physiological Principles MAP = CO x SVR CO = HR x SV Preload Contractility Afterload ~ 1 r4
  8. Basic principles - Vasopressors MAP = CO x SVR CO = HR x SV Preload Contractility Afterload ~ 1 r4
  9. Basic principles - Inotropes MAP = CO x SVR CO = HR x SV Preload Contractility Afterload
  10. Use of inotropes & vasopressors
  11. Drug Classification • Catecholamines : Dopamine, Dobutamine, Adrenaline, Noradrenaline • Phosphodiesterase Inhibitors : Milrinone, Amrinone • Vasopressors : Vasopressin, Phenylephrine • Vasodilators : Nitroglycerine,Sodium Nitroprusside
  12. ????? A 10yrs old child presented to the ER with complaints of nausea,bilious vomiting,abdominal pain with altered sensorium He has history of recurrent bowel obstructions VITALS HR- 162/min RR-32/min T- 101 F BP-70/42 mmHg SPO2-95% in RA The child is in hypotensive shock. crystalloids had to be given at 20ml/kg But iv line couldn’t be secured,so INTRAOSSEOUS line inserted
  13.  After securing intraosseous line and after receiving 3 boluses of crystalloids at 20ml/kg the child remained hypotensive  WHAT IS THE NEXT STEP?  WHAT MEDICATION TO START?  WHAT DOSAGE?  The examination findings important in guiding the therapy are - Capillary refill time - tactile temperature of extremities - mental status - peripheral and central pulses
  14. Choice of inotropes  Cold shock with narrow pulse pressure with low MAP for age - Dopamine is started at 10mics/kg/min - if hypotension is profound and pt is unstable start adrenaline 0.3-0.5 mics/kg/min - if BP is still low Noradrenaline is preferred  cold normotensive shock (MAP normal/high) - Start dobutamine at 7.5-10 mics/kg/min -consider PDE Inhibitors for myocardial dysfunction or pulmonary hypertension
  15.  Warm shock with hypotension - first choice is Nor adrenaline 0.05- 0.5mics/kg/min - if refractory vasopressin or terlipressin can be used  Warm shock with normal BP - aggressive fluid therapy.usually inotropes not required - noradrenaline if diastolic BP excessively low - dobutamine in cases of metabolic acidosis and low ScVo2
  16. Dopamine Hemodynamic effects  Dose dependent - At low doses (0.5-3.0 μg/kg/min), dopamine acts predominantly on D1 receptors in the renal, mesenteric, cerebral and coronary beds resulting in selective vasodilation.  At intermediate doses (3-10 μg/kg/min), also stimulates β1 receptor and increases cardiac output (CO), predominantly by increasing stroke volume with variable effect on heart rate.  At higher dose (10-20 μg/kg/min), the predominant effect is to stimulate α1-adrenergic receptors and produce vasoconstriction with an increased systemic vascular resistance (SVR),and the sum of these effects is an increase in mean arterial pressure (MAP).
  17. DOPAMINE  Indication : Fluid refractory septic shock Cardiogenic shock with vasodilation(warm septic shock)  Side effects • tachycardia • Arryhthmias • Extravasation • Tachyphyllaxis  Reconstitution 1ml=40mg 6 X body weight in 50ml NS 5ml/hr will deliver 10 mics/kg/min 7.5ml/hr will deliver 15 mics/kg/min
  18. DOBUTAMINE  Hemodynamic effects: Improves cardiac output by improving stroke volume & decreasing afterload with minimal tachycardia.  Predominantly 1  Small effect at 2 It is a potent inotrope with weaker chronotropic activity  DOSE 1 ampule = 250mg/5ml 6 X BODY WT in 50ml NS
  19. Indications  Normotensive cardiogenic shock due to primary myocardial pathology Fluid refractory septic shock when the blood pressure is normal /high Cardiogenic shock due to severe hypoxia ischemia of any etiology
  20. Adrenaline  Adrenaline is a potent agonist for β1, β2 and α1 receptors present in cardiac and vascular smooth muscle. Hemodynamic effects:  0.05 – 0.3 mics/kg/min – inotropy, chronotropy  0.3- 1 mics/kg/min – pressor Low dose of adrenaline increases cardiac output because of β1 receptor mediated inotropic and chronotropic effects At higher doses α-receptor mediated vasoconstriction predominates which results increased SVR in addition to increased CO.
  21. indications  Cardiogenic shock with decompensated shock { Improves diastolic BP, resulting in better coronary perfusion & improved myocardial function }  Myocardial dysfunction after cardiac arrest  Anaphylactic shock  Fluid unresponsive dopamine refractory hypotensive septic shock  Severe shock of any etiology
  22. ADRENALINE INFUSION Preparation 1 ampoule 1ml (1:1000 = 1mg / ml) Rate: 1ml/hr = 1mcg/min (Document rate on Syringe Pump & in Patient’s Notes) Dose: 0.05 – 0.5mcg/kg/min (starting infusion rate 0.1 mcg/kg/min) Titrate accordingly to desired BP Calculations : 0.3 x body weight;dilute the required dose in NS(Eg: 10kg - 3ml in 47ml NS) Use single strength in ED, especially if infusion is through a peripheral line. Make sure BP cuff is not on the Arm of the peripheral line. Regularly inspect the site of insertion of the peripheral line.
  23. How to start and titrate • Start infusion @0.1-0.3 mcg/kg/min. • If BP improves but perfusion worsens add inodilators • Doses > 0.6 mics/kg/min are rarely useful as ensuing organ ischemia may lead to MODS Anaphylaxis a) IV Adrenaline 1:10 000 -Dilute 1mg (1ml) to 10 cc N/S -Dose: Give titrating bolus 1 ml up to 0.1ml/kg b) or if IV line not available, give deep IM Adrenaline 1:1000 -Dose: 0.01mg/kg (i.e: Body wt 50kg= 0.5mg = 0.5ml) Max 0.5mg c) IV Infusion if patient not response with boluses.
  24. Norepinephrine  Predominantly stimulates 1 receptors increases SBP &DBP  It has minimal chronotropic effects because of which it is a drug of choice in settings where heart rate stimulation is undesirable.  High doses of noradrenaline can be safely used to maintain cerebral perfusion pressure without significantly compromising the circulatory flow. Uses  Hypotension due to vasodilatation  Warm septic shock refractory to fluid and dopamine
  25. Side effects ↑ Afterload { not appropriate in cardiogenic shock} Worsens perfusion leading to multi organ failure DOSE 0.1-1 mics/kg/min (titrate based on assessment) PREPARATION 0.3 x body weight;dilute the required dose in 5%dextrose Rate: 1ml/hr = 1mcg/min
  26. conclusion  Early recognition and management in initial stages is very critical in treating shock  Ultimate treatment of underlying cause forms the cornerstone of management
  27. That’s All Thank You