inotropic support , dopamine , and other inotropes in children

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Dr Kondekar Santosh venketraman is a MD pediatrician at seth GS medical college and
KEM HOSPITAL MUMBAI INDIA

Department of Pediatrics: KEM Hospital: home page

Dear Pediatricians and resident doctors,

Receptor pharmacology

Agent	Alpha1	Alpha2	Beta1	Beta2	Dopamine
Dobutamine	+	+	++++	++	0
Dopamine	++/+++	?	++++	++	++++
Epinephrine	++++	++++	++++	+++	0
Norepinephrine	+++	+++	+++	+/++	0

Dopamine drip

[6 ><>

It can also be calculated as: Amount of dopamine to be added to 100 ml of IV fluid = 6 multiplied by wt and desired dopamine rate in ug/kg/min; divided by IV fluid rate in ml/hr

Precautions: Before starting dopamine drip; elliminate low volume states by giving two pushes of 20cc/kg of RL/ NS Presence of good urine output justifies good renal perfusion and rules out need for dopamine. Pulse may go weak on dopamine due to its vasoconstrictor action if it were started on low volume. Always start with 5ug/kg/min then go higher as reqd within 30 min. It should be avoided or used judiciously in cases of pulmonary edema, as it increases PVR.

CALCULATIONS ARE SAME FOR DOBUTAMINE, FOR Ad; USE 0.6 INSTEAD OF 6

Agents	Site of Action	Dose mcg/kg/min	Effects
Dopamine	Dopaminergic Beta alfa>beta	0.5-4 4-10 11-20	Renal vasodilator Inotrope Peripheral vasoconstrictor Increased PVR Dysrhythmias
Dobutamine	Beta1 & Beta2	1-20	Inotrope Vasodilatation Beta2 Decreases PVR weak Alfa activity Tachycardia & Extrasystoles
Isoproterenol	Beta1& Beta2	0.05-2.0	Inotrope Vasodilatation Decreases PVR MVO2 Dysrhythmia
Epinephrine	Beta > Alfa	0.05-2.0	Inotrope Tachycardia Decreased Renal Flow MVO2 Dysrhythmia
Norepinephrine	alfa > Beta	0.05-2.0	Profound constrictor Inotrope MVO2 SVR
sodium Nitroprusside	Vasodilator: Arterial greater than Venous	0.5-10	Rapid onset;short dur.n Incrreases ICP V/Q mismatch Cyanide toxicity
Nitroglycerin	Vasodilator: Venous greater than Arterial	1-20	Decreased PVR Increases ICP
PGE2	Complex	0.05-0.2	Vasodilation Open Ductus Arteriosus
Amrinone	PDE3 Inhibitor	1-20	Inotrope Chronotrope Vasodilatation

A simple calculation for Dopamine drip--

To keep rate upto 5 mcg/kg/min add 9 small tuberculin units of dopamine per kg body weight for 12 hr drip.

if you need double rate,double the amt of dopamine i.e. for 10mcg/kg/min add 18 OTU/kg/12 hr drip

now as far as iv fluids are considered:


can be modified as below:


(after first month of life)


2.5 kg = 10 ml/hr = 10 udps/min


5kg = 20ml/hr = 20udps/min


7kg = 30 ml/hr = 30 udps/min


10kg = 40 ml/hr = 40 udps/min


15 kg = 50ml/hr = 50 udps/min


20 kg = 60 ml/hr = 60 udps/min



in between for each Kg add 2 microdrops extra/minute


Thanks to 1ml/hr = 1 udropper minute,


as one macrodrop = 16 microdrops;

1ml= 60 microdrops # 60seconds = 1 minute

For Dopamine drip=
0.0015 × wt. × Rate × duration = ml of Dopamine (for 1ml of Dopamine = 40mg) to be added to the syringe pump.

Weight = in Kg

Rate = µg/kg/min of Dopamine

Duration = in hours




For Dobutamine drip =
0.0048 × rate × duration × wt. = ml of Dobutamine (for 1ml = 12.5 mg of Dobutamine) to be added to the syringe pump.

Weight = in Kg

Rate = µg/kg/min of Dopamine

Duration = in hours

http://www.aic.cuhk.edu.hk/web8/inotropes.htm