inotropes used in shock

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

13. ?????
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

16.  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

18. 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

19.  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

20. 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).

21. 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

22. 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

23. 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

24. 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.

25. 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

26. 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.

27. 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.

28. 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

29. 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

31. conclusion
 Early recognition and management in initial
stages is very critical in treating shock
 Ultimate treatment of underlying cause
forms the cornerstone of management

32. That’s All
Thank You