Chapter 10: Principles of Drug Administration

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Welcome to the Deep Dive.

Today we're really digging into something fundamental,

the non -negotiable rules of pharmacology safety, specifically around drug administration.

That's right.

It's more than just knowing what the drug is.

It's about how you give it safely.

This is really the core of safe patient care, wouldn't you say?

Absolutely.

This systematic approach, these safety protocols,

they're essential across all Canadian health care settings.

We're talking enteral, parenteral, topical routes, the whole thing.

And it's all about sticking to what the regulatory bodies require.

Precisely.

It's the bedrock.

Okay.

So let's start with the basics, but maybe expanded basics.

We all know the five rights, but that's not the whole picture anymore, is it?

Not at all.

Modern practice, well, it demands more.

We're talking about the 10 key rights of medication administration.

10 now.

Okay.

So beyond right roach, drug,

dose,

time, route, patient.

What else?

We add right reason why is the patient actually getting this, then right documentation, which is crucial, right evaluation, and that includes the pre -assessment before giving the drug.

Also right patient education.

And the 10th one, you mentioned it's particularly powerful.

Yes.

The right to review.

It really emphasizes the patient's autonomy.

They have the final say, you know.

That's a critical point.

Okay.

Let's build on that foundation.

Let's talk about what happens before the medication even gets near the patient, the preparation phase.

What are these like administrative firewalls?

Well, first, obviously good hand hygiene.

Use the alcohol rub unless hands are visibly soiled, then soap and water.

Standard stuff.

Okay.

But the big one.

The triple check system.

This isn't optional.

It's mandatory.

You're checking the drug label against the MAR, the medication administration record, three separate times.

Three times.

Walk us through those checks specifically.

Where do errors get caught?

Okay.

First check, when you actually take the drug out of the dispenser or the drawer.

Got it.

Second check during preparation.

So maybe once just before you open the container and then again, right after opening it.

Okay.

Thorough.

And the third?

The third is the really critical one.

It happens right there at the patient's bedside, immediately before you administer it.

Right before it goes in.

And sometimes there's even another layer.

Yeah.

For high -risk meds, think insulin, Heparin the policy usually requires a two -nurse double check.

Adds that extra safety level.

And technology plays a role here too, right?

Barcodes and patient IDs.

Definitely.

Accreditation Canada requires using two patient identifiers.

That's usually name and birth date, or maybe name and an account number.

Not just asking their name.

Right.

And barcode scanning, you see it in figure 10 .4 in the text.

That really helps maximize safety.

It matches the nurse, the patient, and the medication electronically.

It sounds almost foolproof, but I guess there's a risk of just relying on the scanner beep.

That's a valid concern.

The text supports you.

It doesn't replace your clinical judgment.

You still must do that pre -administration assessment.

And that assessment isn't just general wellness.

It's very specific depending on the drug.

Exactly.

Before you give certain heart meds, say digitalis, you absolutely have to check the apical pulse for one full minute.

A full minute.

Yep.

Or for antihypertensives, you check blood pressure, heart rate first.

This gives you that essential baseline.

If the numbers aren't right, you hold the drug.

And one more check before we move on compatibility.

Oh, crucial.

You have to check if drugs can be given together.

Some things like antacids or certain cholesterol meds called bile acid sequestrants.

They interfere with absorption.

So you could give a drug perfectly, but if you give it with the wrong thing.

You've basically canceled it out.

Or worse, compatibility checks are vital.

Okay.

Let's move into the body.

Entral administration, mostly oral meds.

Seems straightforward.

Swallowing a pill.

But what are the hidden dangers here?

Well, the first big risk is aspiration.

Choking.

Right.

So patient positioning is key.

They need to be sitting up, if possible, or at least side -lying, not flat on their back.

Makes sense.

And taking it with water?

Yes.

Usually about 120 to 180 milliliters of fluid helps it dissolve and get absorbed properly.

Okay.

Now the really big rule for oral meds.

The do not crush list.

Why is this such a hard stop?

Because it's incredibly dangerous to crush certain types of pills.

We're talking about enteric -coated ones.

The ones designed to bypass the stomach acid.

Exactly.

Or sustained release, SR.

Extended release, ER types.

Croughing them destroys their whole purpose.

How so?

What happens?

Well, you might irritate the stomach lining if it's enteric -coated, but the really scary part is with SR or ER meds, you break that slow release mechanism, and the patient gets the entire dose meant to last maybe 12 or 24 hours all at once.

Instantaneously.

That can be toxic.

A massive overdose risk.

Wow.

Okay.

Definitely noted.

Do not crush, break, or chew those.

What about meds designed for quick absorption in the mouth?

You mean sublingual under the tongue or buccal in the cheek?

Yeah.

Those are great because they bypass the whole GI tract, get absorbed quickly through the mucous membranes.

What's the key instruction for the patient with those?

They must let it dissolve completely.

No chewing, no swallowing it whole, and no drinking fluids until it's fully dissolved.

And for buccal, alternate cheeks to avoid irritation.

Good tip.

What about kids giving meds to infants and children?

Liquids are usually best.

You use an oral syringe for accuracy, especially for small doses like less than 5 -millil.

And mixing it with food,

tempting to hide it.

Big no -no for essential foods like formula or milk.

The child might develop an aversion to that food later.

Okay.

Good point.

Any other warnings for kids?

Yes.

A critical one.

Never use honey to mask a taste for infants under one year old.

There's a risk of botulism.

Botulism, right.

Okay.

Lastly for this route, feeding tubes, NG tubes, gastrostomy tubes.

Very specific steps here.

Extremely specific.

Patient needs to be upright semi -fowlers or high -fowlers during the administration and for at least 30 minutes after.

Helps prevent aspiration.

And the process itself.

Meticulous.

Crush tablets one at a time, mix each with warm water, usually 15 -30 millil.

Individually?

Yes, individually.

Then you flush the tube with about 30 milliliters of warm water before the first drug.

Then you give the first diluted drug, flush again with about 10 milliliters of warm water.

Give the next diluted drug, flush again with 10 milliliters.

Between each drug, okay.

Between each drug.

And then a final flush of 30 millimills after the last one.

And remember compatibility,

some drugs like phenytoin or carbidopa levodopa just don't go well with tube feedings.

Yeah.

Flush well before and after those especially.

All right.

Now we're getting into parenteral routes, injections.

This feels like the risk level definitely goes up.

We're breaking the skin barrier.

It does.

Technique, site selection, safety, they're paramount here.

Let's start with needle safety.

Basic but absolutely critical.

The number one rule.

Never recap a used needle.

Ever.

Dispose of it immediately in a designated sharps container.

That's non -negotiable.

Detects everyone from needle stick injuries.

What about preparing the medication itself?

Vials versus ampoules.

Okay.

So vials often have a rubber stopper.

You need to inject air into the vial equal to the volume of drug you plan to withdraw.

This equalizes the pressure.

Right.

Makes it easier to draw up.

Ampoules are different.

They're glass, single use.

First, you tap the top to get all the liquid down.

Then you break the neck carefully away from you.

In drawing it up, there's a special needle involved.

Yes.

This is crucial.

You must use a filter needle to draw the medication out of a glass ampoule.

Wait, a filter needle?

To catch any tiny glass fragments that might have fallen in when you broke the ampoule, you absolutely don't want to inject glass particles into a patient.

Makes sense.

But you don't inject with the filter needle, right?

Correct.

You draw up with the filter needle, then you switch to a new, regular sterile needle for the actual injection.

Huge safety point.

Okay.

Filter needle for ampoules, then switch.

Got it.

Now, intramuscular.

IM injections.

Deep into the muscle, 90 -degree angle.

Sight selection is key here, and it's changed, hasn't it?

It really has.

The ventrogluteal site that's on the side of the hip is now the preferred and safest site for pretty much everyone, including adults and children.

Why is that the preferred one?

Because it's a deep muscle well away from major nerves like the sciatic nerve and large blood vessels.

The vastus lateralis, the thigh muscle, is still often used for infants and immunizations.

And the one we used to use a lot, the back pocket area.

The dorsogluteal site.

It's no longer recommended.

The risk of hitting the sciatic nerve is just too high.

That's a major practice update people need to know.

Huge update.

Okay.

Moving to subcutaneous or subcut,

under the skin, into the fatty tissue.

Right.

Usually smaller volumes, maybe 0 .5 to 1 mm max.

Angle is typically 45 or 90 degrees, depending on the patient's tissue and needle length.

Any special precautions, especially with drugs like heparin or lovinox?

Anticoagulants.

Yes.

Very important.

For heparin and low molecular weight heparins like anoxaparin, you do not aspirate, meaning you don't pull back the plunger to check for blood.

Okay.

No aspiration.

And you do not massage the site after injection.

Both actions increase the risk of causing bruising or a hematoma.

Got it.

No aspirate, no massage for those.

I think I've heard about an air bubble technique with some pre -filled syringes.

Yes.

The low molecular weight heparin pre -filled syringes often have a small airlock, maybe 0 .2 mlo.

You generally inject that air bubble last.

It helps seal the medication in and prevent leakage.

Interesting.

What about really irritating drugs?

Is there a way to stop them from leaking back up the needle track?

There is.

It's called the Z -Trac method.

You use this for meds known to irritate subcutaneous tissue like iron dextrin.

How does Z -Trac work?

You use your non -dominant hand to pull the skin and underlying tissue sideways, laterally, before you inject.

Then you give the IM injection, wait a few seconds, withdraw the needle, and then release the skin.

Ah, so the skin slides back over the injection site.

Exactly.

It creates a zigzag path sealing off the needle track and trapping the medication deep in the muscle, preventing it from leaking back out.

Clever.

And briefly, intradermal ID injections.

Those are very shallow, just under the epidermis.

Like for TB tests, the angle is really low, 5 to 15 degrees, almost parallel to the skin.

And the goal is to see?

A small bubble, or bleb, right under the skin, like a tiny mosquito bite.

That tells you you're in the right spot.

No aspiration needed here either.

Okay, final routes.

Intravenous, 4 for speed, and topical for more localized effects.

4V seems like the highest risk category.

Why is that?

It's the speed.

Once that drug hits the bloodstream via IV, its effect is almost immediate, and crucially, you can't get it back.

No recall button.

None.

So any error, wrong drug, wrong dose, wrong rate, the consequences are instant and potentially much more severe than other routes.

That's why infusion pumps are mandatory for kids, for instance, to control the rate precisely.

Makes sense.

What about IV push, or bolus, giving meds directly from a syringe into the IV line?

Requires extreme care with timing.

Most IV push meds are given slowly, over 1 to 5 minutes.

You absolutely need to use a watch or timer.

Slow push?

Any exceptions?

Adenosine is a big one.

It's used for certain heart rhythm issues and needs to be pushed super fast, like in 2 or 3 seconds, but that's unusual.

And are there drugs you never give IV push?

Oh, definitely.

Potassium chloride, KCL, is a major one.

It can cause cardiac arrest if pushed.

Also, certain potent drugs like dopamine or vancomycin are typically given as infusions, not direct pushes.

Always check the specific drug guidelines.

Always check.

Okay, what about adding meds via IV piggyback, IVPB, a smaller bag connected to the main line?

Right, often used for antibiotics.

Smart pumps are common now, adding another layer of safety.

And there's a technique called back priming.

Back priming, what's that?

It's where you use the fluid from the main IV bag, the primary infusion, to flush out the secondary tubing before hanging the next piggyback dose.

You lower the secondary bag and let the primary fluid run back up into it briefly.

It clears the old medication out of the secondary line without having to disconnect anything, which reduces the risk of contamination.

Clever, but sometimes you can't back prime.

Correct.

You wouldn't do it if the primary infusion contained something critical that can't be paused or messed with, like heparin or potent vasopressors.

Got it.

Okay, shifting to topical routes now.

Eyes first, but it's the trick with eye drops.

After putting the drop in the lower conjunctival sac, you need to apply gentle pressure with a finger on the patient's nasolacrimal duct, that little corner of the eye near the nose.

Why there?

For about 30 to 60 seconds.

It blocks the tear duct temporarily, preventing the medication from draining into the nasal passages and getting absorbed systemically.

Keeps the drug work mostly in the eye.

And wait a few minutes between different eye meds.

Smart and ear drops.

There's an age thing here, right?

Yes, a key difference.

For adults and kids over three years old, you pull the outer ear, the pinna, up and back to straighten the ear canal.

Up and back for older folks.

But for infants and children under three, you pull the pinna down and back.

Their ear canal anatomy is different.

Down and back for the little ones?

Good distinction.

And cold ear drops are bad.

Oh yeah, they can cause severe dizziness or vertigo.

If they're stored in the fridge, warm them gently first, maybe by rolling the bottle between your hands.

Okay.

Inhaled medications next.

If someone needs two different types, like a rescue inhaler and a steroid.

There's a specific order.

The bronchodyl always comes first.

Why first?

Because it opens up the airways.

Then when the patient uses the second inhaler, usually the corticosteroid, that anti -inflammatory medicine can get deeper into the lungs where it needs to work.

Makes perfect sense.

Open the doors first.

Anything else for inhaled steroids?

Yes.

Crucially, rinse the mouth with water after using a steroid inhaler.

Swish and spit.

Helps prevent oral thrush, a fungal infection.

And tracking doses is important.

Just shaking the canister isn't accurate.

Good point.

Lastly, transdermal patches.

Sticky patches on the skin.

Big warnings here.

The absolute number one rule.

Never cut a transdermal patch.

Why not?

Cutting it destroys the special membrane that controls the drug's release rate.

You risk releasing way too much medication all at once, potential overdose.

Okay, never cut.

What else?

Always remove the old patch before applying a new one.

Clean the skin.

Rotate application sites to avoid skin irritation.

And disposal.

Especially for strong pain patches like fentanyl.

Very important.

Fold the used patch in half, sticky sides together so the medication side is covered.

For potent drugs like fentanyl, disposal might need to be in a sharps container or per specific facility policy due to risk of diversion or accidental exposure.

Right.

And something like nitroglycerin ointment.

Not a patch, but topical.

Right.

That comes with special dose measuring paper.

You apply the measured amount onto the skin, usually securing it with tape.

The key is you do not rub or massage the ointment into the skin.

Why no rubbing?

It would increase the absorption rate unpredictably, which you don't want with nitroglycerin.

Wow.

Okay, that was a lot of detail, but incredibly important detail.

From the 10 rights to specific Z -Track techniques, each step is a safety measure.

It really is.

Mastering these things, the checks, the sites, the do not crush rule, knowing when not to massage, using a filter needle, it turns theoretical knowledge into precise, safe action.

It shows how complex just giving medication actually is when you do it right.

Absolutely.

That complexity is the standard for safe practice.

So if we boil this down for you, our listener, what's a final thought to connect all these dots?

Well, think about the evaluation piece we mentioned.

Consider the huge difference between giving, say, sublingual nitroglycerin for chest pain, where you need to assess the effect almost minute by minute.

Right.

It acts super fast.

Versus giving a long acting oral tablet that might take an hour or more to even start working, requiring a totally different monitoring schedule.

How does that drastically different timeline change your required clinical assessment and response?

That difference in onset and duration really dictates the vigilance needed,

something to definitely keep front of mind.

Exactly.

It highlights how the route and formulation fundamentally shape the safety net you need to provide.