Chapter 37: Concepts of Care for Patients With Hematologic Problems

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Welcome to the deep dive.

If you've ever felt a bit lost trying to connect the dots between blood disorders and those big physiological concepts, well, you're in the right place.

Today, we're really digging into the hematologic system, kind of like the body's engine room, and we'll show you exactly how problems here mess with four absolutely vital concepts, perfusion, immunity, clotting, and gas exchange.

Yeah, absolutely.

And we've taken a pretty dense chapter on complex hematologic disorders and really tried to boil it down.

Our mission here is to cut through the noise,

leave you with the high yield stuff, the core pathophysiology, the assessment cues you just have to know, and the priority management strategies.

Think of it as the fast track to getting up to speed.

Okay, sounds good.

And we're kind of anchoring this whole discussion around two main examples, two exemplars.

First up is sickle cell disease, which is, I mean, just a textbook, albeit tragic example of messed up perfusion.

It really is.

Okay, so let's unpack that.

Let's start with the basic genetic problem.

Sickle cell disease stems from just a single genetic mutation, right?

It changes hemoglobin A, the normal stuff, into this abnormal hemoglobin S or HBS.

So what actually happens structurally when this HBS doesn't get enough oxygen?

Well, when oxygen levels dip, that HBS molecule folds

incorrectly.

It doesn't stay flexible and round like it should.

Instead, the whole red blood cell gets distorted into this stiff, fragile crescent or sickle shape.

And here's the real kicker.

These sickled cells, they're sticky, they clump up, and they block blood flow, especially in the small capillaries.

That's what we call a vaso -occlusive event, a VOE.

And blocking blood flow, that's never good, leads to tissue damage.

Exactly.

You get this horrible cascade, first hypoxia, then ischemia, lack of blood flow, and eventually, if it goes on long enough, infarction, actual tissue death.

Wow.

But it's not just the blockage, is it?

I remember reading these cells don't live as long either.

Not even close.

That's the other major problem driving the chronic illness side of SCD.

A normal red blood cell hangs around for about 120 days.

A sickled cell, maybe 10 to 20 days tops.

That's a huge difference.

It is.

And this constant destruction, this hemolysis, leads straight to chronic hemolytic anemia.

The body is always, always trying to catch up, making new cells, but it can't keep pace.

Okay, so the crises themselves, the painful ones, they're usually triggered by something specific, right?

Some kind of stressor.

Instead of just listing them all, is there like a unifying principle?

What makes the cells sickle?

Yeah, there is.

The common thread is anything that basically puts stress on the body's oxygen supply or its hydration levels.

Think of it like the Ds in the eyes, dehydration is a big one.

Deoxygenation is so high altitude, really strenuous exercise,

and infection.

Infection is huge because it causes fever, increases metabolic demand, basically creates systemic hypoxia.

So avoiding those is key for prevention.

Absolutely foundational, yeah.

So when a crisis does hit, we know intense pain is the hallmark symptom, right?

The tissue screaming for oxygen.

But what about the bigger picture, the systemic signs of damage from this chronic poor perfusion?

Right, because the body's been dealing with this for a long time.

Because of the chronic anemia, the heart is constantly working harder to compensate.

That puts patients at risk for high output heart failure.

Yeah.

So you might actually hear things like murmurs or an S3 heart sound on assessment.

Interesting.

And I think that's a great example of what we're talking about.

We're talking about the respiratory refill.

But when we talk about really critical complications, the lungs are a major area of concern.

You mean acute chest syndrome, ACS.

Exactly that, ACS.

It's life -threatening.

It's actually the most common cause of death in SED patients.

Wow.

And it can look like pneumonia at first, you know, cough, shortness of breath, maybe an infiltrate on the chest x -ray.

But often it's causing infarction, not necessarily just infection.

And it can get bad fast.

Very fast.

It can quickly spiral into respiratory failure and what we call M -O -D -S, multiple organ dysfunction syndrome, which is basically total system collapse from the sustained lack of oxygen to the tissues.

Devastating.

Okay.

Are there any unique visual things we should look for during an assessment?

Yeah, a couple.

Jaundice is pretty common.

All that rapid red blood cell breakdown releases a ton of bilirubin.

Right.

For patients with darker skin, you might not see it easily on the skin itself.

So check the roof of the mouth or look at the sclera, the whites of the eyes, right near the cornea.

That's where you'll spot that yellow tinge.

Good tip.

Also, be aware of priapism in male patients.

That's a painful prolonged erection caused by sickled cells trapping blood in the penis.

Needs urgent attention.

Okay.

And the labs confirm it, right?

Low hematocrit, but a high reticulocyte count because the body's trying so hard to make new cells.

Exactly.

And the definitive diagnosis comes from hemoglobin electrophoresis.

That test shows the percentage of HBS, which will be really high, like 80 to 100 % in SCD.

Got it.

So let's switch gears to managing this.

What are the absolute priorities?

Okay.

Priority one is managing that severe pain and priority two is stopping that domino effect into M -O -D -S.

Makes sense.

For the acute crisis pain, we're talking IV opioids,

usually morphine or hydromorphone, and importantly, scheduled doses, not PRN.

You need to stay ahead of this pain.

This usually goes on for at least 48 hours.

And you mentioned something important there about addiction concerns.

Yes.

And it's critical.

The level of pain in a VOE is driven by actual tissue ischemia.

It's severe organic pain.

Concerns about treating this level of suffering.

It's an ethical and physiological necessity.

Really important point.

Are there any meds that actually work on the underlying disease process long -term?

Yes, thankfully.

Hydroxyurea is a mainstay.

It works by stimulating the body to produce more fetal hemoglobin.

HBF binds oxygen much more tightly than HBS does, so it actually helps prevent the cells from sickling in the first place.

Okay.

Big action alert here, though.

Hydroxyurea is a teratogen.

It causes birth defects.

So any woman of childbearing potential taking it must be on strict, reliable contraception, both during treatment and for some time after stopping.

Crucial safety point.

Any newer drugs?

Yeah, there are newer options, too, like Endari, which is L -glutamine,

and Crozanolazumab.

Crozanolazumab is a monoclonal antibody, and it works by making the cells less sticky, reducing that adhesion that causes vaso -occlusion.

Okay, that's quite a list of interventions.

If we zoom out again, thinking about sickling causing poor perfusion, what's the one big principle to remember for crisis care, like the do's and don'ts?

The guiding principle is maximize blood flow and oxygen delivery.

Simple enough.

So number one, give oxygen.

Even if their pulse ox looks okay, supplemental O2 can help reduce further sickling.

Number two, hydrate like crazy.

Why hydrate so much?

Because often their blood is hypertonic, kind of thick and sticky from dehydration and the disease process itself.

So you hit them with hypotonic IV fluids initially, often at a pretty fast rate, like 200 millimiters per hour, to dilute the blood and improve flow.

Makes sense.

And then think about body position and environment.

Keep the room warm at least 72 degrees Fahrenheit or 22 Celsius cold, causes vasoconstruction, which is the last thing you want.

Keep their extremities extended, not bent.

And specifically,

avoid raising the knee catch on the bed.

That position can impede venous return from the legs, promoting stasis, and you guessed it, more sickling.

Got it.

Maximize flow and oxygen.

Okay, let's shift concepts slightly.

If SCD is about blood clogging, anemia is more about the delivery track, the RBC being missing or just not working right.

Exactly.

Anemia isn't really a disease itself, more a clinical signpost pointing to an underlying problem.

The general signs are what you'd expect from poor gas exchange, looking pale, feeling cool, heart racing, fatigue, getting breathless easily with activity.

But there are different types and we need to tell them apart.

Absolutely.

The most common type worldwide is iron deficiency anemia.

If you look at the cells, they're small microcytic.

Okay.

The really crucial thing here, especially in adults, is finding out why they're iron deficient.

You have to investigate.

Usually looking for abnormal GI bleeding.

Could be an ulcer, could be something more serious.

You can't just supplement iron without finding the cause.

Right.

Contrast that with vitamin B12 deficiency, sometimes called pernicious anemia.

The cells look different here.

Yeah, here the cells are large, macrocytic, or megaloblastic.

Pernicious anemia specifically is caused by a lack of intrinsic factor.

Ah, the stomach protein needed to absorb B12.

Exactly.

If the stomach lining is damaged, often by an autoimmune process, and can't make intrinsic factor, you simply can't absorb B12 from food.

So for true pernicious anemia, the treatment is lifelong B12 injections, bypassing the gut entirely.

And B12 is critical because it impacts more than just blood cells, right?

The nervous system.

That's the key differentiator.

Both B12 and folic acid deficiency cause macrocytic anemia,

but only B12 deficiency causes neurological problems.

What should we look for?

Well, you might see glossitis, that classic smooth, beefy red tongue, but pay close attention to neurological symptoms.

Peristhesias, which is numbness or tingling, usually in the hands and feet, and problems with balance or coordination.

Okay.

If you see those neural signs alongside the anemia,

you strongly suspect B12 deficiency.

Folic acid deficiency doesn't do that.

Good distinction.

And the last main type of anemia, a plastic.

A plastic anemia is kind of the worst case scenario in terms of production.

It's basically bone marrow failure.

Total failure.

Pretty much.

The marrow just stops producing enough of all blood cell types.

So you get pancidopenia, low red cells, anemia, low functional white cells, leukopenia, and low platelets, thrombocytopenia, often caused by exposure to toxins, certain drugs, radiation, or sometimes viruses.

Okay.

So we've covered perfusion and gas exchange issues.

Let's move to immunity with our next big exemplar, leukemia.

This is cancer, right?

A failure of cellular regulation involving white blood cells.

That's right.

Leukemia is essentially uncontrolled production of immature white blood cells, called blast cells, inside the bone marrow.

Immature cells.

Yeah, they're non -functional.

They proliferate so wildly that they just crowd out everything else.

They suppress the normal production of healthy red cells, platelets, and importantly, mature functional white blood cells.

So even if the total white count is high, the patient can't fight infection.

Exactly.

They might have a sky -high WBC count on paper, but those cells are useless blasts.

This leaves the patient profoundly immunocompromised, leading to a massive risk of infection.

Okay.

So infection risk is paramount.

What's the single most critical assessment finding we need to jump on in a patient with severe neutropenia, that low count of functional neutrophils?

This is a code red critical rescue moment.

In any patient known to be neutropenic, even a slight temperature elevation, just one degree Fahrenheit or half a degree Celsius above their baseline, needs to be reported immediately.

Just one degree?

Yes.

That fever might be the only sign you get that a life -threatening infection is brewing before they crash into full -blown sepsis.

Don't wait.

Report it.

Wow.

Okay.

So infection control measures must be incredibly strict then.

Absolutely meticulous.

We're focused on two things,

preventing autocontamination, where the patient's own gut or skin bacteria overgrow and cause infection and cross -contamination, which is infection from external sources like healthcare workers or the environment.

So strict hand washing, aseptic technique for everything.

Everything.

And simple things too, like environmental control.

No standing water allowed in the room.

That means no fresh flowers or plants in water.

Make sure denture cups are empty and cleaned regularly.

Places where pathogens like Pseudomonas love to grow.

Makes sense.

Now for some types of acute leukemia, the only potential cure is pretty intense.

Hematopoietic stem cell transplantation or HSCT.

Can you walk us through that?

Yeah.

It's a major undertaking.

It starts after the stem cells have been collected, either from the patient themselves earlier that's autologous or from a compatible donor, allogeneic.

Then the patient undergoes the conditioning regimen.

This involves very high doses of chemotherapy, sometimes with total body irradiation.

The goal is brutal, but necessary, to completely obliterate the patient's existing disease bone marrow,

making space for the new stem cells.

Wiping the slate clean.

Exactly.

Then comes day TDO, transplantation day.

The harvested stem cells are simply infused intravenously, much like a regular blood transfusion.

Simple infusion.

Anything special about the setup?

Yes.

Very important action alert here.

You must use standard IV tubing, the kind with a larger bore.

Do not use blood administration tubing.

Why not lead tubing?

Because the filter in standard blood tubing is designed for red blood cells and is too fine.

It will actually trap the precious stem cells, preventing them from getting into the patient's bloodstream and reaching the bone marrow.

You'd essentially filter out the cure.

Wow.

Okay.

Critical detail.

And after the infusion,

then it's just waiting.

Then it's the waiting game.

And it's a dangerous time.

We're waiting for engraftment.

That's when the new stem cells find their way to the bone marrow, settle in, and start producing healthy blood cells.

This usually takes about 14 to 21 days.

And during that time, the patient has basically no immune system.

Exactly.

They're incredibly vulnerable to infection.

And in allogeneic transplants, where donor cells are used, there's another huge risk.

Graft versus host disease, or GBHD.

What's that?

That's when the donor's immune cells, specifically T cells that came along with the stem cells,

recognize the patient's body tissues, commonly the skin, liver, and gut as foreign, and they attack.

It can range from mild rashes to severe, life -threatening organ damage.

A major complication.

Is there anything else specific to watch for related to the conditioning?

Yes.

Another serious complication, often linked to the high -dose chemo, is sinusoidal obstructive syndrome,

or SOS.

It used to be called veno -occlusive disease, BOD.

What happens in SOS?

It's basically damage and blockage of the tiny blood vessels, the sinusoids within the liver.

This leads to liver congestion, impaired function, and portal hypertension.

You'll see symptoms like jaundice, painful liver enlargement in the right upper quadrant, and a site's fluid buildup in the abdomen.

Usually happens within the first month post -transplant.

Okay, another serious one to monitor.

Let's shift gears again.

We've talked efficiency with anemia, now let's talk excess.

Polysothemia vera, or PV.

This is classified as a cancer too, right?

But of red blood cells.

And it ties into our concept of clotting.

That's right.

PV is one of the myeloproliferative neoplasms.

The hallmark is massive, uncontrolled overproduction, primarily of red blood cells,

but also usually white blood cells and platelets.

So hypercellularity across the board.

And what's the main consequence of having way too many cells in your blood?

The blood becomes incredibly thick, viscous.

We call it hyperviscosity.

That's sludge.

Pretty much.

And thick, sludgy blood doesn't flow well.

It leads to poor tissue profusion or stasis, and greatly increases the risk of clot formation thrombosis.

That's the major danger.

Heart attack, stroke, DVT, PE.

Okay.

How might a patient with PV look or feel?

They often have a very distinct appearance.

Their face and mucous membranes can look really dark red or flushed, almost purplish.

We call that plethora.

Plethora.

Got it.

And they frequently complain of intense itching or pruritus, especially after a warm bath or shower.

It's thought to be related to abnormal histamine release from the excess mass cells and poor skin profusion.

So how do you treat blood that's literally too thick?

Well, the most straightforward way is to remove some of it.

The cornerstone of management is therapeutic phlebotomy, just like donating blood.

But done regularly, maybe every few weeks or months, to physically reduce the red cell mass and lower the hematocrit.

Sometimes, aphoresis is used to remove just the red cells.

Makes sense.

Anything else?

Aggressive hydration is also key.

Aiming for at least three liters of fluid daily helps decrease that blood viscosity.

And often, patients will be on medications to prevent clots, like low -dose aspirin or sometimes stronger anticoagulants, depending on their risk profile.

Okay, so if they're prone to clotting, but might also be on anticoagulants, and the disease itself can affect platelet function,

safety must be a big focus.

Bleeding precautions.

Absolutely critical.

Even though they have high platelet counts, the platelets often don't function correctly, leading to a paradoxical risk of bleeding alongside the clotting risk.

So standard precautions?

Yes.

Patient education needs to hammer this home,

use an electric shaver, not a razor, use a sock -bristled toothbrush,

avoid constipation, and be incredibly careful about taking any over -the -counter meds that affect bleeding, especially NSAIDs like ibuprofen or naproxen, and definitely aspirin unless it's specifically prescribed by their hematologist.

Got it.

Okay, our final topic is something that touches almost all areas of hematology care.

Transfusion therapy.

Giving blood products.

This seems like an area where nursing responsibility is huge for safety.

It is absolutely paramount.

Errors in blood transfusion can be lethal, so the protocols are strict for a reason, designed to prevent mistakes, especially human error, which causes most severe reactions.

What are the absolute must -dos before you even hang the blood?

Okay, non -negotiables.

First, you need a valid provider's prescription and informed consent from the patient.

Second, and this is a huge Joint Commission National Patient Safety Goal, two RNs must verify the patient's identity and the compatibility of the blood product

immediately before starting the infusion.

Two RNs, what are they checking?

They're meticulously comparing the information on the blood bag label, the blood type, RH factor, unit number, expiration date against the patient's wristband, and the transfusion slip.

Name and medical record number must match exactly on all three.

No shortcuts.

Okay.

And what about the IV line itself?

Can you run blood with other fluids or meds?

Absolutely not.

Only one fluid is compatible with blood products.

Normal saline, 0 .9 % sodium chloride.

You can prime the tubing with it, and you can flush the line with it afterwards, but you can never add any medications to the blood bag or infuse any other IV solution through the same line while the blood is running.

It can cause the blood to clump or lyse.

Only normal saline.

Got it.

What about during the transfusion?

What's the nurse's role then?

Vigilance.

You, the nurse, must stay with the patient for the first 15 to 30 minutes of the threatening reactions, like an acute hemolytic reaction due to ABO incompatibility, typically happen within that first 15 minutes or the first 50 milliliter blood infused.

You need to be right there to recognize it and act immediately.

Okay.

Anything else for specific patient groups?

Older adults.

Yes.

Good point.

Older adults or anyone with heart failure or kidney problems are at high risk for fluid overload from the transfusion volume.

We call this PACO, transfusion associated circulatory overload.

Right.

To prevent it, you need to infuse the blood much more slowly for these patients, maybe over two to four hours per unit instead of faster, and monitor them closely for signs of overload like shortness of breath, crackles in the lungs, or JVD.

Makes sense.

Okay.

The worst case scenario, you're there for the first 15 minutes and suddenly the patient gets a fever, chills, complains of low back pain, maybe feels breathless or has this terrible sense of impending doom.

You suspect an acute hemolytic reaction.

What do you do?

What's the absolute first priority?

Stop either transfusion immediately.

That's number one.

Do not let another drop infuse.

Okay.

Stop the blood.

Then what?

Second step is critical.

Disconnect the blood tubing from the patient's IV hub.

Do not just flush the line with saline.

You don't want any more of that incompatible blood going in.

Remove the entire blood tuning setup.

Got it.

Remove the tubing.

Keep the five open.

Yes.

Keep the IV access patent by attaching a new IV tubing setup with fresh normal saline and running it, usually at a keep vein open rate, unless they need fluids for shock.

Then notify the provider in the blood bank immediately,

assess the patient rapidly, and likely initiate a rapid response or code depending on their condition.

Save the blood bag and tubing to send back to the blood bank for analysis.

Stop.

Disconnect.

New saline line.

Notify.

Okay.

Crucial sequence.

Absolutely life -saving.

Wow.

Okay.

That was definitely a deep dive into some complex hematology.

We hit the poor perfusion and tissue damage from sickle cell crises.

The vital importance of infection prevention for leukemia patients when their counts are low.

Right.

The clotting risks from thick blood in polycythemia vera.

And those non -negotiable safety steps for giving blood.

It covers a lot of ground.

It does.

And if we try to tie this all together, thinking about the bigger picture,

almost every disorder we talked about, from SED needing lifelong management to leukemia survivors needing long -term monitoring after HSCT, they're chronic complex conditions.

Sure.

They demand a huge amount of careful self -management from the patient long after they're discharged.

So maybe a final thought for you, the listener, is this.

How does really understanding this pathophysiology, these risks, these treatments, how does that detailed knowledge actually change your approach to educating patients for the long haul?

Helping them stick with complex plans and providing that ongoing support they need.

That's a great question to reflect on.

How do we translate this acute knowledge into long -term empowerment for our patients?

Excellent thought.

Well, we really hope this deep dive into the source material leaves you feeling more confident, well -informed, and ready to apply this critical knowledge when you need it most.

Thanks for joining us.