Chapter 14: Nutritional Support & Parenteral Therapy

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Here is a scenario that I have to admit keeps me up at night.

Picture this.

You have a patient in the ICU.

They've survived the initial trauma, maybe it was a car accident, maybe a massive surgery.

The bleeding has stopped, the vitals are, you know, they're stabilizing on the monitor and everyone kind of takes a deep breath, but it's day five and they haven't eaten.

And on the surface, that sounds manageable.

We tend to think, oh, they have reserves, they have body fat, they can run on empty for a bit.

Exactly.

We think of the human body like a bear in hibernation or something, but looking at the research on nutritional support, specifically chapter 14 of our pharmacology text, we realize that reserves is a really dangerous myth in a hospital setting.

It is.

Because after a few days, the body doesn't just burn fat, it starts cannibalizing itself.

It's a metabolic switch.

And once that switch flips, you aren't just dealing with hunger, you're dealing with organ dysfunction, immune system collapse, and a body that literally cannot heal the wounds you just spent hours stitching up.

That is exactly what we are unpacking today.

We are the Last Minute Lecture team.

And this isn't just a deep dive into how to feed a patient.

This is a deep dive into the physiology of survival.

We're tackling chapter 14, nutritional support.

We are going to cover the tubes, the complex chemistry of the fluids, and the incredibly high stakes management of torrential nutrition feeding through the veins.

This is the fuel that keeps the engine running.

If this system fails, the antibiotics, the surgeries, the fancy interventions,

none of them matter.

Not at all.

So here's our roadmap.

We're going to walk through the chapter exactly as it's written.

We start with the physiology, why the body crashes without fuel.

Then we move to enteral nutrition, getting food into the gut.

Then we'll tackle the pharmacy side of things, how to administer medications through those tubes without, you know, causing a total disaster.

And finally, we'll explore parental nutrition, which is a whole different beast with some of the highest risks in nursing care.

So buckle up.

Let's get into section one, the physiology and necessity of nutritional support.

To understand why this chapter is in a pharmacology book, we have to kind of redefine how we view nutrients.

Right.

In this context, we aren't talking about culinary enjoyment.

Nutrients are the bioactive substances that nourish the body.

They provide energy, promote growth, and regulate body processes.

So it's the baseline requirement for existence.

And the text makes a really stark point right at the beginning.

Inadequate intake leads to malnutrition.

Now in a healthy person,

malnutrition is, you know, a slow process, but in a hospitalized patient, it accelerates.

Let's drill down into that.

The text talks about a critical window.

How long can a person actually survive without nutrients?

Well, it depends on weight, genetics, and illness severity.

But here's the real differentiator, stress.

When you're healthy and you skip meals, your body adapts.

It sort of slows down to preserve energy.

But when you're critically ill, trauma, burns, sepsis, your body enters a hypermetabolic state.

So instead of slowing down, the engine actually revs up.

Exactly.

The body is just screaming for resources to repair tissue and fight infection.

And if you don't provide that fuel from the outside, the body starts breaking down its own protein stores to find it.

And we aren't just talking about burning a little belly fat here.

No, we are talking about catabolism.

The body breaks down muscle tissue.

And remember, the heart is a muscle.

The diaphragm, which you need to breathe, is a muscle.

And critically, visceral proteins are broken down.

These are the building blocks of your immune system.

That connects to the statistic in the text that really stood out to me.

It says malnutrition leads to a poor immune response.

There isn't just some vague correlation.

It's a supply chain failure.

Precisely.

You cannot build white blood cells or antibodies if you've cannibalized the amino acids required to make them.

That is why the text highlights a very specific time frame for trauma or burn patients.

24 to 48 hours.

Right.

For those high -stress patients, nutrition needs to start within 24 to 48 hours of admission.

If you wait longer,

that catabolic spiral becomes very, very difficult to reverse.

So early nutrition isn't just about keeping them full.

It's about stopping that self -destruction.

Yes.

The text lists some benefits of early enteral nutrition specifically.

Yes.

Enteral meaning using the gut.

And the benefits are profound.

First, it restores intestinal motility.

It keeps the gut moving.

Use it or lose it.

Literally.

If the gut just sits idle, the mucosal barrier, that's the lining of the intestines, starts to atrophy.

When that barrier breaks down, bacteria from the gut can leak into the bloodstream.

Which causes sepsis.

Exactly.

So early feeding reduces the movement of bacteria, preventing infection.

It also improves wound healing and ultimately it shortens the hospital stay.

Okay, so we know we need to feed them.

But how much?

The text gives us some math.

It does.

Let's look at fluids first.

The typical requirement is 30 to 35 millidol per kilogram per day.

Okay, so for a 70 -kilogram adult, that's roughly 2 .1 to 2 .5 liters of water.

Correct.

You have to maintain that hydration volume.

Now for calories, a healthy person needs about 2 ,000 calories a day.

But going back to that hypermetabolic concept, a critically ill patient needs about 50 % more.

Wow.

So we're looking at 3 ,000 calories a day?

Roughly, yes.

Because they are basically running a marathon while lying in bed.

As a nurse, you know, we're the first line of defense in spotting this.

What are the red flags the text gives us?

When do I look at a patient and say, okay, we need to intervene here?

There are some very clear parameters.

If a patient has had a 10 % weight loss within the past 3 to 6 months, that's a major, major warning sign.

Okay.

Or if they've had little or no nutrition for more than five days.

Five days seems to be the magic number for the danger zone.

It is.

At that point, you absolutely must consider supplementation.

Now,

the first choice is always oral feeding.

The old -fashioned way.

If the GI tract works and the patient can swallow, use it.

But we see a lot of patients with anorexia.

And we should clarify, in the text, this doesn't necessarily mean anorexia nervosa, the psychiatric condition.

Right.

That's a key distinction.

It refers to the physiological lack of appetite.

Stress, illness, pain, anxiety, medications, they all just kill your appetite.

So if they can swallow but just won't eat enough,

what do we do then?

We bridge the gap.

We use commercial puddings, high -calorie bars,

and nutritional drinks.

We slide these in between meals to boost the caloric intake without overwhelming them with massive plates of food.

Okay, that makes sense.

But what if they can't swallow?

What if they had a stroke or they're intubated but their stomach is still working?

That brings us to section two.

Entral nutrition.

The gut route.

This is the bread and butter of nutritional support, pun intended.

Entral nutrition, or EN, is the delivery of nutrients or fluid via a tube directly into the GI tract.

But, and this is the golden rule you absolutely must memorize, it requires a functional, accessible GI tract.

If the gut works, use it.

Always.

Because, as we mentioned, using the gut maintains that intestinal barrier and prevents bacteria from migrating into the blood.

But accessing the gut isn't one size fits all.

We have a diagram in the text, figure 14 .1, that looks a bit like a subway map of the digestive system.

How do we choose which route to take?

It really comes down to two variables, duration and aspiration risk.

Let's start with duration.

Short term versus long term.

Short term is defined as less than four weeks.

For this, we use the natural entry point, the nose.

We have the nasogastric tube, the NG tube, which goes from the nose down the esophagus and parks itself in the stomach.

That's the standard approach.

But what if the patient has a weak stomach or maybe severe reflux?

That brings us to the second variable, aspiration risk.

If the patient has a weak gag reflux, or if their stomach isn't emptying well, there's a risk that the food will come back up the esophagus and spill into the lungs.

Which is catastrophic.

Aspiration pneumonia.

Exactly.

To prevent that, we bypass the stomach.

We use a nasojoidinal or a nasojunal tube.

These go through the nose, pass through the stomach and end up in the small intestine.

Why does that help?

What's the mechanism?

It's because of the pyloric sphincter.

That's the muscle valve between the stomach and the small intestine.

Once the tube and the food are past that gate, it acts as a barrier.

It is much, much harder for food to reflux back up from the intestine into the lungs.

So intestine feeding is safer for aspiration risk, but probably harder to place.

A bit, yes.

Now what if the patient needs this for months?

Or permanently?

We can't leave a tube in their nose forever.

No, absolutely not.

It causes tissue necrosis and it's incredibly uncomfortable.

For long -term nutrition, we go directly through the abdominal wall.

We have the gastrostomy tube, often called a PEG tube, which goes straight into the stomach.

PEG stands for percutaneous endoscopic gastrostomy, right?

Yes.

Percutaneous means through the skin.

Endoscopic is how they guide it visually.

And gastrostomy means an opening into the stomach.

And what if they have that aspiration risk but need long -term feeding?

What's the solution then?

Then we use a jejunostomy tube or a G -tube.

Same concept.

Through the skin, but it lands directly in the jejunum of the small intestine.

Let's talk about the hardware for a second.

The text mentions these tubes are made of silicone or urethane.

They're flexible, but they have an Achilles heel.

They clog.

They clog so easily.

These tubes are narrow.

If you put thick, blenderized food down them, or, and this is the big one, if you don't crush medications properly, you create a blockage.

And a blocked tube isn't just an annoyance, is it?

Oh, it's a crisis.

You might have to pull the tube and reinsert a new one, which is traumatic for the patient.

It's expensive.

And it carries its own set of insertion risks.

There's also the risk of dislodgement.

Yes.

A patient coughing violently, vomiting, or even a confused patient pulling up the tube can move it out of place.

And if an NG tube moves from the stomach up to the esophagus or, God forbid, into the trachea, and you start the feeding pump.

You are drowning the patient in formula.

So verification is literally life or death.

How do we know the tube is where it's supposed to be?

The text is very, very clear on this.

The gold standard is an X -ray.

When that tube is first placed, you do not use it until a radiologist confirms the tip is in the right spot, period.

What about the ongoing checks?

I remember learning in school about listening for the whoosh of air.

Yeah, the text mentions those methods, injecting air and listening for gurgles or checking the pH of the aspirated fluid.

But it explicitly notes their limitations.

They are not foolproof.

So really, rely on the X -ray initially and then check the external markings on the tube daily to make sure the length hasn't changed.

Exactly.

If the tube was at the 50 centimeter mark yesterday and today it's at 30 centimeters, it has moved.

You stop everything.

OK, the tube is in.

It's patent.

Now, what are we actually feeding them at section three?

Entral solutions and delivery methods.

This is where the science gets really specific.

Not all formula is just, you know, medical milk.

Table 14 .1 breaks it down into four distinct categories.

Let's walk through them.

First up is polymeric.

Think of polymeric as a complete meal replacement.

It's milk based or blenderized whole foods.

It contains complex proteins, carbohydrates and fats.

Who is this for?

This is for the patient with a fully functional GI tract.

Their body can still do the work of digestion, breaking down those complex proteins and absorbing them.

It's also isotonic, which means it matches the body's fluid balance.

OK, next on the list is modular.

Modular formulas are individual components.

So imagine you have a patient who is getting enough calories, but their wounds aren't healing.

So they need extra protein.

You would add a protein module.

It allows you to tailor the nutrition kind of like a cart nutrition.

Exactly.

Then we get to the sci fi stuff, semi elemental or elemental.

These are pre digested formulas.

The nutrients are hydrolyzed, meaning they are chemically broken down into their smallest components, amino acids and simple sugars.

Why would we need that for patients whose gut is partially broken?

Maybe they have a partial bowel obstruction, short bowel syndrome or malabsorption issues like Crohn's.

Their gut can't do the heavy lifting of digestion.

So we do it for them in the lab.

And finally, specialty formulas.

These are disease specific.

These are fascinating.

They adjust the macronutrients based on the organ failure.

For example, a diabetes formula helps with glycemic control.

It'll be lower in carbs, higher in fiber.

A weenal formula for kidney failure has low sodium, low potassium and fluid restrictions.

And the respiratory formula.

That one always confuses people.

It's all about carbon dioxide.

When your body metabolizes carbohydrates, it produces CO2 as a byproduct.

If you have a patient with COPD or lung failure, they cannot exhale that CO2 efficiently.

They're retaining CO2.

Right.

So we give them a formula that is higher in fat and lower in carbohydrates.

Fat metabolism produces less CO2, so it actually reduces the workload on the lungs.

That is brilliant.

OK, so we have the formula.

How do we get it into the patient?

There are four different delivery methods.

First is continuous.

This uses an infusion pump running 24 hours a day at a very slow rate.

Who gets this?

The critically ill or anyone we're feeding into the small intestine.

You have to remember, the small intestine is a flow pipe, not a storage tank.

It can't handle big bursts of food.

It needs a trickle.

Then there is intermittent.

This mimics a meal schedule.

Every three to six hours, you give 300 to 400 millimiters over about 30 to 60 minutes.

You can use a pump or just gravity hanging the bag on a pole.

It's cheaper and gives the patient breaks from being hooked up.

Exactly.

Then we have the bullis method.

The food bomb, as I like to call it.

Essentially, you take a large syringe and push 250 to 400 milliliter directly into the tube in about 15 minutes.

It's very, very fast.

But I sense a but coming.

But it is hard on the system.

Dumping that much volume that quickly can cause nausea, vomiting, cramping and severe diarrhea.

We typically reserve bullis feeding for ambulatory patients, people who are healthy enough to walk around and have a strong stomach.

Finally, SoClic.

SoClic is a hybrid.

It's continuous feeding, but only for part of the day, usually eight to 16 hours and often at night.

This is great for rehabilitation, right?

Yes.

It frees the patient up during the day to go to physical therapy or sit in a chair without being tethered to a pole.

OK, we are feeding them, but things can go wrong.

Section four, enteral complications in nursing safety.

The text calls out the big three.

Dehydration, aspiration, pneumonitis and diarrhea.

Let's start with dehydration.

This seems counterintuitive.

I mean, we are pumping liquid into them all day.

How do they get dehydrated?

It's the chemistry of the formula.

Many of these formulas are high protein or hyperosmolar.

They have a lot of solutes packed in.

So osmosis kicks in.

Yes.

The high concentration in the gut draws water out of the body cells and into the intestine to try and balance things out.

If you aren't giving enough free water along with the formula, the patient cells literally dry out.

That is a crucial nuance.

Just because it's liquid doesn't mean it's hydrating.

Correct.

The recommendation is usually 30 to 35 millimiters of water per kilogram per day to maintain that balance.

Next is the monster aspiration pneumonitis.

We touched on this, but let's go deeper.

This is the most life threatening complication.

It's not just choking.

If formula enters the lungs, the pH in the bacteria causes severe inflammatory reaction.

It causes tissue necrosis, lung death and pneumonia.

So how do we prevent it?

The text introduces a caring intervention regarding positioning.

Gravity is your best safety tool.

You must keep the head of the bed, the H .O .B.

elevated 30 to 45 degrees during feeding.

No feeding while flat.

Never.

And if you're doing intermittent feeding, you keep them sitting up for 30 to 60 minutes after the meal to ensure the stomach has time to empty.

Then there is the concept of checking residuals.

This is a classic nursing ritual.

It is before you start a feeding or every four hours during a continuous feed, you attach a syringe to the tube and you pull back.

You're measuring how much fluid is just sitting in the stomach.

You're checking if the stomach is actually doing its job and emptying.

Exactly.

If you pull back 500 milliglutes of fluid, the stomach isn't emptying.

If you keep pumping more food in, it has nowhere to go but up, which leads to aspiration.

What's the cutoff?

The general rule, though, you always, always follow your hospital's policy is if the residual is greater than 150 millilay, you hold the feeding.

You wait an hour, recheck.

If it's still high, you call the provider.

The third complication is diarrhea.

Incredibly common.

It can be caused by the formula running too fast, bacterial contamination of the bag

or antibiotics wiping out good gut flora.

Or the meds we put in the tube.

Yes.

Liquid medications often contain sorbitol as a sweetener.

Sorbitol is a laxative.

So if a patient is getting multiple liquid meds, they are getting a massive dose of laxative without anyone realizing it.

How do we manage it?

We can slow the infusion rate.

We can dilute the formula or we can switch to a formula that has fiber to help bulk up the stool.

Before we leave safety, we have to talk about the Joint Commission warning on misconnections.

This is nightmare fuel.

Hospitals are full of tubes, forby lines, feeding tubes, tratch cuffs.

There have been tragic cases where a nurse accidentally connected a feeding tube to a tracheostomy tube, pumping food directly into the lungs or to an IV line.

Pumping formula directly into a vein, which is instantly fatal.

The warning is simple.

Trace the line.

Do not just grab a port and plug it in.

Trace the tube from the patient's body all the way back to the connection point to be 100 percent sure what you are holding.

Trace the line.

It's a mantra.

OK, let's move to section five.

Entral medications.

Because our patients are sick, they need drugs.

And if they have a tube, that's usually how they get them.

But you cannot just crush everything and shove it down.

That is a recipe for failure.

The hazards listed are occluded tubes, reduced drug effect or even toxicity.

Step one is preparation.

You must verify if the drug is crushable.

You consult a pharmacist or the hospital's do not crush list.

What are the absolute do not crush categories?

Timed release or extended release capsules.

If you crush a pill that is designed to release slowly over 24 hours, you destroy that mechanism.

The patient absorbs the entire dose in five minutes.

That's an overdose.

A massive one.

Also, enteric coated pills.

They are coated to protect the stomach lining or to survive stomach acid.

Crushing them destroys that protection.

And sublingual.

Those are meant to dissolve under the tongue and enter the capillaries directly.

If you put them in the stomach, the acid destroys them completely.

What about bulk forming laxatives?

We mentioned these earlier.

Psyllium.

Metamucil.

Never put these in a feeding tube.

They absorb water and they expand in a glass.

That's fine.

In a tiny tube, they turn into concrete.

You will never get that tube open again.

So liquid forms are obviously preferred.

But if you have to crush a safe med, what is the process?

The text outlines a very specific ritual.

First, prepare each medication separately.

Do not mix crushed pills together in one cup.

Why not?

The cocktail approach seems like it would save time.

It's dangerous chemistry.

You're mixing binders, fillers and active ingredients that were never meant to touch.

They can react, form crystals or clump together into a clog.

So separate cups.

Then dissolve the crushed med in about 15 milliliters of warm water.

And then the administration sequence.

Flush, med, flush.

Exactly.

Flush the tube with 15 milliliters of water.

This clears the line of any residual formula.

OK.

Step two, administer the dissolved medication.

And step three, flush again with 15 milliliters of water.

This pushes the med into the stomach and clears the line for the next thing.

And if you have a second med, you repeat the entire process.

Flush, med B, flush.

You need that water buffer between everything.

And the cardinal sin.

What's the one thing you never do?

Never mix medications directly into the feeding bag.

Why?

Because of physical incompatibilities.

The medications can react with the proteins in the formula.

It can curdle the formula into a thick cheese like substance that blocks the tube instantly.

Gross and dangerous.

There is also a note about specific drugs like phenytoin, which is Dilantin.

Yes, phenytoin is an anti -seizure medication.

It has a high affinity for proteins.

If you give it while the formula is running, the drug literally binds to the formula proteins and the patient absorbs almost none of it.

So their seizure risk goes way up.

Right.

For these drugs, you have to stop the feeding for 30 minutes.

Flush, give them a flush, wait another 30 minutes and then restart the feeding.

You need a clean window for absorption that covers the gut.

But what if the gut is completely non -functional?

What if there is a total blockage, sphere pancreatitis or short bowel syndrome?

That is where we leave the enteral world and move to section six.

Parental nutrition,

the vein route, also known as TPN for total parental nutrition or hyperalimentation.

Parental means alongside or outside the enteron, which is the gut.

We are injecting nutrients directly into the bloodstream.

This sounds exponentially more complicated.

It is.

We are bypassing the body's natural filters, the stomach lining, the liver.

We are putting a complex chemical soup straight into circulation.

What is in the solution?

It's a custom mix.

Amino acids for protein,

carbohydrates in the form of dextrose, electrolytes, vitamins and trace elements.

And often we add lipid emulsions, which are fats, to provide essential fatty acids and concentrated calories.

The text highlights the caloric sources specifically.

Dextrose provides about 60 to 70 percent of the energy needs.

The lipids provide the remaining 30 percent.

But here's the catch.

The text warns about high glucose.

This is the critical concept you have to grasp.

The dextrose concentration in PN is incredibly high.

It makes the solution hypertonic.

What does that mean for the veins?

A hypertonic solution is much more concentrated than blood.

If you inject it into a small peripheral vein like in your hand, it sucks water out of the vein walls.

It causes immediate irritation, inflammation and phlebitis.

It can ruin the vein.

So you can't run TPN through a regular five.

No, you need a central line.

You need a central venous catheter.

Where does that go?

It's inserted into a large vessel like the subclavian or internal jugular vein.

And the tip is threaded all the way down until it sits in the superior vanacava right above the heart.

Why the vanacava specifically?

Because of the blood flow.

The volume of blood rushing through the vanacava is massive.

It instantly dilutes that hypertonic sugar solution, protecting the vessel walls from damage.

The text distinguishes between a central line and a PICC line.

A PICC line, peripherally inserted central catheter, starts in the arm, in the periphery, but it's very long.

It threads all the way of the arm and ends in the vanacava.

So it acts like a central line.

When do we use which?

PICC lines are great for intermediate term weeks to a few months.

But for long term TPN, or if the arm veins aren't usable, we place a central line directly into the chest.

Now, feeding through vein comes with some terrifying risks.

Section seven, complications of parenteral nutrition.

Table 14 .2 lists these, and they are intense.

We can categorize them into three buckets, mechanical, infection and metabolic.

Let's start with mechanical things that happen during insertion, pneumothorax.

This is a collapsed lung.

When the doctor is inserting the needle into the subclavian vein, which is right under the collarbone, the apex of the lung is millimeters away.

A slip at the hand.

And you puncture the lung.

Air escapes into the chest cavity.

The patient will complain of sudden sharp chest pain and shortness of breath.

You'll hear decreased breath sounds on that side.

Then there's the air embolism.

This feels like something out of a spy movie, but it's a very real risk.

It is.

The venous system in the chest is under negative pressure.

It's actively sucking blood toward the heart.

If you open the catheter to change the tubing and you don't clamp it, the vein sucks air in.

Exactly.

And that air bubble travels to the heart.

It acts like a vapor lock.

The heart pumps, but it's just churning foam.

Blood stops moving.

It is fatal.

It's not treated instantly.

The text gives us a specific prevention technique.

The Valsalva maneuver.

This is crucial nursing knowledge.

When you are changing the tubing or the cap, you ask the patient to turn their head away to keep the site clean and perform the Valsalva maneuver.

Take a deep breath, hold it and bear down like they're having a bowel movement.

Why?

Because bearing down increases the pressure inside the chest, the inter thoracic pressure.

It makes the pressure inside the vein higher than the air pressure outside.

So air gets pushed out instead of being sucked in.

Exactly.

Physics saves lives.

Next complication category,

infection.

This is the most common serious complication.

Remember, the PN solution is full of dextrose.

It is warm sugar water.

It's a bacteria heaven.

It is the perfect culture medium.

If bacteria get into that line, they multiply instantly.

This can lead to rapid sepsis.

So the nursing action is strictly sterile.

Strict aseptic technique during all dressing changes and tubing changes.

You change the tubing every 24 hours.

You change the dressing every 48 hours or per your policy.

And you watch their temperature like a hawk.

Finally, metabolic risks.

We are messing with their blood sugar on a massive scale here.

Hyperglycemia is very common.

We are infusing high dose sugar directly into the blood.

Pancreas might not be able to produce enough insulin to keep up.

So we monitor blood glucose every four to six hours, even if the patient isn't diabetic.

And we usually start the infusion slowly, like 40 to 60 milliliters per hour to let the pancreas catch up.

But the opposite can happen, too, right?

Hypoglycemia.

Yes.

This is a rebound effect.

If the patient has been on TPN for days, their pancreas is working over time, just pumping out insulin.

If the TPN bag runs empty and you stop the infusion abruptly, the sugar supply cuts off, but the insulin is still high.

And their blood sugar crashes.

Hypoglycemic shock.

So what is the safety tip?

The text has a specific instruction for when the new bag is late from pharmacy.

You keep a bag of 10 percent dextrose D10 in the room or on the unit.

If the PN runs out and the new bag isn't ready, you hang the D10 immediately.

It acts as a bridge.

Right.

It provides enough sugar to prevent that rebound hypoglycemia until the TPN arrives.

You never, ever just turn it off and walk away.

That is a pro tip that belongs on every nursing cheat sheet.

D10 is your safety net.

Let's bring this all together with Section 8.

Clinical judgment and nursing process.

The text walks us through a case study.

Let's apply what we've learned.

We have a 50 year old female patient.

She's had complex GI surgery.

She has been NPO, nothing by mouth for five days.

So she's in that critical window.

Exactly.

She has a central line and an order for parenteral nutrition.

The nurse starts the shift.

What's the assessment?

First, baseline weight and vital signs.

We need to know where we are starting from.

Then lab monitoring.

The nurse checks the morning labs.

Her potassium is 3 .2 Meql.

That is hypoglycemia, low potassium.

Normal is 3 .5 to 5 .0.

So priority action number one.

The nurse looks at the TPN bag label.

Because TPN is custom mixed, right?

Correct.

The pharmacist mixes it based on the daily labs.

If the patient has low potassium, the provider should have ordered extra potassium in today's bag.

The nurse has to verify that the solution matches the patient's needs.

And if the bag says no potassium and her level is 3 .2, do you hang it?

No, you call the pharmacy and you call the provider.

You don't hang the wrong fuel.

Next, the nurse inspects the insertion site.

Looking for erythema, which is redness, any drainage or swelling.

Signs of that infection we are so worried about.

And interventions.

The text lists some practical handling rules.

Refrigerate PN solution until use.

It's organic material.

It can spoil.

But you take it out an hour before hanging to let it warm to room temperature so it doesn't cause V -ing spasm.

And the rule about no additives.

Never draw blood from the TPN line and never add meds to the TPN bag on the unit.

The risk of contamination and incompatibility is just too high.

You dedicate that line to nutrition only.

Finally, the case study mentions patient teaching.

The nurse instructs the patient on the Valsalvo maneuver.

This turns the patient into a partner in safety.

If I am changing your tubing, I need you to hold your breath and bear down.

Explaining why helps with compliance.

And telling them what to watch for.

If you feel sudden chest pain or shortness of breath, you tell me immediately.

It creates a safety loop.

The nurse is vigilant and the patient is empowered.

This has been a massive deep dive.

We have covered the entire spectrum of keeping a patient fueled.

Let's head to the outro.

It really is a journey.

We started with the invisible threat of cellular starvation.

That metabolic switch that turns the body against itself.

We moved to the enteral route, navigating the anatomy of the nose, stomach and intestine to find the safest path for food.

We broke down the chemistry of formulas and the danger of crushing meds.

Flush, med, flush.

I'm never going to forget that.

And we finished with a high wire act of parenteral nutrition, central lines, hypertonic sugar solutions and the constant vigilance against air embolisms and sepsis.

It really highlights that feeding in a hospital isn't just a basic care task.

It is complex pharmacology and physiology.

It is life support.

Before we go, I want to leave you with one final thought from the text that really stuck with me.

It says,

respect the patient's beliefs about refusing PN.

It is a profound point to end on.

Artificial nutrition is a medical treatment.

It involves invasive tubes, risks and burdens.

It's not just serving dinner.

And sometimes at the end of life or in a chronic illness, a patient or a family might decide that the burden of the tube or the line outweighs the benefit.

It brings us back to the ethical core of nursing.

We have all this technology, all these formulas and all this knowledge.

But ultimately, we treat the person, not just the metabolic process.

Respecting their choice to decline is just as important as knowing how to hang the bag.

Well said.

Thank you for sticking with us through this deep dive into Chapter 14.

We know pharmacology is tough, but you are tougher.

Keep studying, keep questioning and remember to trace your lines.

This has been the last minute lecture team.

Thanks for listening.

We'll catch you in the next deep dive.

Goodbye.