Dopamine

In this lesson, we'll go over the medication dopamine and all of its effects, including indications, precautions and contraindications, and pediatric dosages.

Dopamine is a naturally occurring catecholamine – any of a class of aromatic amines that includes a number of neurotransmitters – that has direct alpha and beta adrenergic effects depending on the dose administered.

When the dose administered is greater than 5mcg/kg per minute in pediatric patients, dopamine will act directly on the beta 1 receptors, which causes an increase in both myocardial contractility and heart rate.

When the dose of dopamine administered is between 10 and 20mcg/kg per minute, the alpha receptors are typically stimulated. This causes an increase in systemic vascular resistance, also known as vasoconstriction.

Dopamine Indications

Now let's take a look at dopamine indications.

Dopamine can be quite effective in treating hypotension when there are signs and symptoms that the patient is in shock. A dopamine infusion can be titrated to treat shock associated with poor contractility or systemic vascular resistance that is unresponsive to fluid administration.

Dopamine Precautions and Contraindications

Dopamine has a few precautions and contraindications to be aware of.

Pediatric Dosage of Dopamine

Now let's look at the pediatric dosage of dopamine.

Dopamine should be administered via IV or IO access and the most common infusion rate is between 2 and 20mcg/kg per minute. However, make sure to titrate the dosage and drip rate to the patient's response.

A Word About Vascular Access for Pediatric Patients in Cardiac Arrest

As mentioned in the previous two Word sections, the priorities for drug delivery routes during pediatric advanced life support are, in order of preference:

1. Intravenous (IV)
2. Intraosseous (IO)
3. Endotracheal (ET)

In the previous two lessons, we covered IV and IO administration in pediatric patients. In this lesson, we'll dig a little deeper into administering medications via the endotracheal route.

Endotracheal (ET) Drug Delivery

The IV and IO routes are preferred over the endotracheal route when administering medications. However, lipid soluble medications can be administered via the ET route. These include atropine, epinephrine, naloxone, lidocaine, and vasopressin.

However, it's important to note that there are limited human studies about ET vasopressin administration as well as limited studies that can provide dosing guidelines for most medications administered via the ET route.

If you are considering the administration of medications to pediatric patients via the ET route while also performing CPR, keep these ideas in mind as you do:

1. Drug absorption from the tracheobronchial tree is unpredictable, which means that the concentrations and effects of the medication being administered will be unpredictable.
2. The optimal dose of most medications administered via the ET route is unknown.
   a. The administration of medications into the trachea results in lower blood concentrations of that medication than when the same dose is administered via the IV or IO routes.
   b. Animal studies suggest that the lower epinephrine concentrations achieved when medications are delivered via the ET route may produce transient but detrimental β-adrenergic-mediated vasodilation.
3. Recommended dosages of medications administered via the ET route are higher than for those administered by both the IV and IO routes.
   a. For instance, the recommended dose of epinephrine that is administered via the ET route is 10 times the dose of epinephrine administered via the IV and IO routes.
   b. While the typical dose of other medications delivered via the ET route is 2 to 3 times the dose that will need to be administered via the IV and IO routes.