Atropine

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

Atropine sulfate is a parasympatholytic drug that increases sinus or atrial pacemakers and enhances atrioventricular conduction. In general, atropine accelerates the heart rate by reducing the activity of the parasympathetic nervous system.

The parasympathetic nervous system is often described as the rest and digest part of the autonomic nervous system. Atropine works by blocking this action.

The autonomic nervous system is a control system that acts mostly unconsciously as it regulates bodily functions, such as the heart rate, respiratory rate, pupillary response, digestion, urination, and sexual arousal.

Atropine Indications

Now let's take a look at some indications for atropine.

First of all, atropine is recommended over epinephrine and is used for the treatment of bradycardia in pediatric patients when that bradycardia is due to:

• Excessive vagal tone
• Cholinergic drug toxicity, like organophosphates
• Complete atrioventricular blocks

Atropine Precautions and Contraindications

There are a couple of precautions and contraindications when it comes to administering atropine.

1. Be aware that the patient may experience tachycardia following the administration of atropine. However, atropine-induced tachycardia is generally well tolerated in most pediatric patients.
2. Atropine is not recommended, and has no therapeutic benefit, for pulseless rhythms such as asystole, pulseless electrical activity (PEA), V-tach, or VFib.

Pediatric Dosage of Atropine

Let's take a closer look at the pediatric dose of atropine.

Atropine, whether administered via IV or IO, will be delivered at .02mg/kg. You can deliver a second dose after five minutes one time if needed.

The minimum dose of atropine is 0.1mg. And the maximum single dose of atropine is 0.5mg.

Atropine can also be administered via an endotracheal (ET) tube if either IV or IO access is not an option. And the ET tube dose of atropine is .04 to .06mg/kg.

A Word About Vascular Access for Pediatric Patients in Cardiac Arrest

As mentioned in the previous Word section of the amiodarone lesson, 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 lesson, we covered IV administration in pediatric patients. In this lesson, we'll dig a little deeper into administering medications via the IO route.

Intraosseous (IO) Drug Delivery

If, for whatever reason, IV access is not available when treating a pediatric patient, medications and fluids can be safely and effectively delivered via the IO route. In fact, the intraosseous route is also useful as the initial route of vascular access, rather than merely the backup to IV, in cases of pediatric cardiac arrest.

Important points to note about IO access include the following:

• IO access can be established in pediatric patients in all age groups
• IO access can often be achieved quickly, as in 30 to 60 seconds
• The IO route is preferred over the endotracheal tube route
• Any medication or fluid that can be administered intravenously can also be administered via the intraosseous route

IO cannulation can provide access to a non-collapsible marrow venous plexus, which serves as a safe, reliable, and rapid route for the administration of resuscitation medications and fluids in pediatric patients.

The technique includes using a rigid needle, preferably one that has been specifically designed for IO use, or bone marrow needle. Although an IO needle with a stylet is preferred to prevent obstruction of the needle with the cortical bone during insertion, standard hypodermic needles, spinal needles, and butterfly needles can also be used effectively and inserted successfully.

Powered IO insertion devices are widely used in the U.S. and are commercially available and used by both military and civilian healthcare providers, such as the battery-powered EZ-IO, hand-powered Fast1, Fast Combat, and Fast Responder models.