• At low doses (0.5–2.5 μg/kg/min) it increases renal and mesenteric blood flow by stimulating dopamine receptors. The ↑ renal blood
flow results in ↑ GFR and ↑ renal sodium excretion
• Doses between 2.5 and 10 μg/kg/min stimulate B1 receptors causing ↑ myocardial contractility, stroke volume and cardiac output
• Doses > 10 μg/kg/min stimulate a receptors causing ↑ SVR, ↓ renal blood flow and ↑ potential for arrhythmias
The distinction between dopamine’s predominant dopaminergic and a effects at low doses and B effects at higher doses is not helpful in clinical practice due to marked inter-individual variation.
Uses:
Septic shock
Low cardiac output
Contraindications
Attempt to increase urine output in patients inadequately fluid
resuscitated
Phaeochromocytoma
Tachyarrhythmias or VF
Administration
• Larger doses: 2.5–10μg/kg/min to increase cardiac contractility
• Doses >10 μg/kg/min stimulate a-receptors and may cause renal vasoconstriction
200 mg made up to 50 ml glucose 5% or sodium chloride 0.9% (4000 μg/ml)
Dosage chart (ml/h)
Weight
(kg)
|
Dose
(ug/kg/min)
| ||||
2.5
|
5.0
|
7.5
|
10
|
15
|
|
50
|
1.9
|
3.8
|
5.6
|
7.5
|
11.3
|
60
|
2.3
|
4.5
|
6.8
|
9.0
|
13.5
|
70
|
2.6
|
5.3
|
7.9
|
10.5
|
15.8
|
80
|
3.0
|
6.0
|
9.0
|
12.0
|
18.0
|
90
|
3.4
|
6.8
|
10.1
|
13.5
|
20.3
|
100
|
3.8
|
7.5
|
11.3
|
15
|
22.5
|
110
|
4.1
|
8.3
|
12.4
|
16.5
|
24.8
|
Give via a central vein via accurate infusion pump Reduce dosage if urine output decreases or there is increasing tachycardia or development of new arrhythmias
How not to use dopamine:
Do not use a peripheral vein (risk of extravasation)
So-called ‘renal dose’ dopamine for renal protection (0.5–2.5 μg/ kg/min) is no longer recommended (Crit Care Med 2008; 36: 296–327)
Do not connect to CVP lumen used for monitoring pressure (surge of drug during flushing of line)
Incompatible with alkaline solutions,e.g.sodium bicarbonate, furosemide, phenytoin and enoximone
Discard solution if cloudy, discoloured, or >24 h old
Adverse effects:
Ectopic beats
Tachycardia
Angina
Gut ischaemia
Vasoconstriction
Cautions:
MAOI (reduce dose by one-tenth of usual dose)
Peripheral vascular disease (monitor any changes in colour or temperature of the skin of the extremities)
If extravasation of dopamine occurs – phentolamine 10 mg in 15 ml sodium chloride 0.9% should be infiltrated into the ischaemic area with a 23-G needle
Organ failure:
May accumulate in septic shock because of ↓ hepatic function
How not to use dopamine:
Do not use a peripheral vein (risk of extravasation)
So-called ‘renal dose’ dopamine for renal protection (0.5–2.5 μg/ kg/min) is no longer recommended (Crit Care Med 2008; 36: 296–327)
Do not connect to CVP lumen used for monitoring pressure (surge of drug during flushing of line)
Incompatible with alkaline solutions,e.g.sodium bicarbonate, furosemide, phenytoin and enoximone
Discard solution if cloudy, discoloured, or >24 h old
Adverse effects:
Ectopic beats
Tachycardia
Angina
Gut ischaemia
Vasoconstriction
Cautions:
MAOI (reduce dose by one-tenth of usual dose)
Peripheral vascular disease (monitor any changes in colour or temperature of the skin of the extremities)
If extravasation of dopamine occurs – phentolamine 10 mg in 15 ml sodium chloride 0.9% should be infiltrated into the ischaemic area with a 23-G needle
Organ failure:
May accumulate in septic shock because of ↓ hepatic function
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