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13 Nursing Myths You Probably Fell For

Emergency (ER) Nursing Tips
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Not everything you learn on the job is factual, and there are many nursing myths that are still commonly believed and “passed on” today. While some myths are rooted in truth, other nursing myths don’t seem to have any evidence of substance to back them up. 

There is nothing more embarrassing than learning something, teaching that to others, and then realizing that it’s not actually accurate!

You might be aware of some of these, but there are other common nursing myths that you may not be aware of, so make sure you read all 13!

Nursing Myths -Featured Image

1. Hemolysis of blood

One common nursing myth is that “leaving blood tubes sit for too long can cause hemolysis of the blood”, which is not true.

When blood hemolyzes, the red blood cells “lyse” or split open. This lysis releases their intracellular contents and disrupts normal lab values.

Remember that intracellular potassium is much higher than extracellular potassium. This means that hemolysis will cause false elevations in potassium. It also can falsely elevate magnesium, phosphorus, liver enzymes, ammonia, and the anion gap. It can falsely lower RBCs, hematocrit, PTT, and more!

So obviously we don’t want the blood to hemolyze, and this common nursing myth assumes that by leaving the blood sit for too long at the bedside, this can cause or worsen this hemolysis.

Hemolysis actually occurs when there is damage to the red blood cells, usually when being drawn into the tube due to collection technique. True causes of hemolysis include:

  • Drawing from an IV with poor blood return
  • Drawing from an old IV
  • Having the tourniquet on for an excessive amount of time or excessive clenching of fists
  • Vigorous shaking or mixing of the tubes. Tubes should be gently turned 5-10 times to mix the anticoagulant.
  • Needle or catheter partially occluding the vein wall (you may feel vibration)
  • Tubes that aren’t filled completely

Blood drawn from IVs are much more likely to hemolyze, but finding a site with great blood return and large veins should help. That is one more reason why the AC is a great choice for the ER to place new IVs – they’re great for blood return!

As it turns out, while leaving blood sit too long shouldn’t cause hemolysis, leaving blood to sit too long CAN alter results, and this all depends on each type of tube and the actual lab test. But regardless – this doesn’t cause hemolysis.

Sometimes blood tubes are drawn and left at the bedside, mainly within the ED. However, these tubes need to be run within a certain amount of time. The following blood tubes for common blood tests can be kept at room temperature with accurate results for:

  • CBC: up to 24 hours
  • CMP: should be centrifuged within 2 hours for accurate glucose and potassium results
  • PT/PTT: up to 2 hours if on heparin, otherwise up to 4 hours
  • D-dimer: up to 8 hours

Nursing Myths - hemolysis

2. The MONA Nursing Myth

As nurses, we encounter those with chest pain all the time. In school we are taught the acronym MONA – Morphine, Oxygen, Nitroglycerin, and Aspirin. These are our “treatment” for those with chest pain when it is suspected to be cardiac.

While this isn’t completely wrong, its oversimplification, and sometimes these treatments can actually harm the patient!

The Nursing Myth: Oxygen

When a patient comes in with chest pain, we traditionally throw them on the monitor, apply oxygen, and anticipate to give nitro and aspirin once ordered.

Don’t fall into the trap of applying oxygen to every patient with chest pain, even if you suspect a true heart attack! First, check their pulse ox and apply oxygen only if their SPO2 is <94% (some sources even recommend 90%).

This is because too much oxygen can be bad for the patient. Hyperoxia has been shown to cause direct vasoconstriction of the coronary arteries.

If the patient is significantly short of breath or has CHF, it probably isn’t a bad idea to apply some oxygen, but just make sure it stays between the 94-99% range.

Will this kill the patient? Probably not – but no benefit has been found when applying oxygen to a normoxic patient, and it could potentially harm them. So only apply oxygen if absolutely necessary.


In addition to nitro, morphine can be given for chest pain and was traditionally taught as a mainstay of treatment. However – morphine given to patients with heart attacks has been shown to potentially cause harm!

In fact, patients with NSTEMI who were treated with morphine were found to have an overall increased chance of dying. Scientists aren’t really sure why – but they think it may interfere with the antiplatelet effect of Plavix, Brlinta, etc.

Can morphine still be given? Of course! But should probably be limited to those with severe pain after the other measures have already been implemented.

Nursing Myth - MONA

Related Content: Cardiac Lab Interpretation (Troponin, CK, CK-MB, and BNP)

3. The Bigger IV the Better

Nurses love to place large IV catheters, especially in the ED. And oftentimes an 18 gauge is great peripheral access to obtain in those with trauma or who may need large volumes of fluid or blood.

However, an 18g should not be the standard IV size that you place in every patient. Most fluids and medications can be given through 20g and even 22g. But what’s the harm of placing a 16 or an 18g just because you are confident that you can?

First off, it may be more difficult to place and lead to failure. Second, it will be more painful for the patient. Lastly and probably most importantly – bigger IV catheters have higher rates of mechanical phlebitis and thrombophlebitis.

Nursing Myth - Mechanical phlebitisInstead of placing the largest IV catheter that you are able to, you should instead place the size that you think will be needed for the anticipated therapy. As a general rule of thumb:

  • 18g: If suspecting large volumes of fluids may be needed (codes, hypotension, critical patients)
  • 20g: If you need IV access for boluses, maintenance fluid, IV pushes, CT angiography (in an AC line), or blood transfusion
  • 22g: If you need IV access for boluses, maintenance fluids, IV pushes, or other IV medications

You can never go wrong with a 20g, and true emergencies will benefit from an 18g.

Related Articles:

4. A Nurses Nose Knows CDIFF

Clostridium Difficile is a bacterial infection of the intestines which can cause severe diarrhea, hospitalization, severe inflammation of the colon, and even death in older at-risk patients.

If you have ever worked in the hospital – you have had experience with CDIFF. The profuse diarrhea, the putrid smell, the patients who just seem to get it over and over again. CDIFF can be very difficult to completely get rid of.

Nursing Myths - CDIFOne thing my preceptor on my first nursing unit taught me was that “CDIFF has that smell”. And while I agree that it often does have a smell, are nurse’s noses sensitive enough to tell regular diarrhea from CDIFF diarrhea?

There were previous studies that seemed to suggest that a nurse could tell the difference. However, when conducted in a blinded controlled laboratory setting, nurses were unable to tell the difference between CDIFF stool and regular diarrhea. They did not perform better than chance.

The nurse’s individual experience or confidence in detecting the smell played no impact on their results.

So what does this mean? Well – you May be able to smell CDIFF, but you should always notify the physician/APP and obtain a sample to send to the lab to be safe. If the patient has liquid diarrhea and no stool sample has been sent, don’t assume it isn’t CDIFF just because “it doesn’t smell like it”.

5. If a Patient Leaves Insurance Won’t Cover Their Visit

When I was a new nurse, I was taught that “If a patient leaves AMA – insurance may not cover their visit”. This was something I would pass onto my patients – not to try and manipulate them to stay, but instead to make sure they understood there might be financial consequences of leaving AMA.

What I didn’t know was that this just isn’t true. There is simply no basis for this claim. Leaving AMA does not impact insurance coverage.

Over half of medical residents and almost half of attending physicians commonly believed this myth, and nurses are no exception.

We should be intentional about explaining the consequences of leaving AMA. This includes the patient getting sicker or potentially dying as a result of refusing medical treatment. However, we should not mention insurance coverage since this is not true and can manipulate the patient into staying when that is against their wishes.

6. High Fevers Cause Seizures

Many nurses, especially those who work in the ED, have probably witnessed febrile seizures. These are common in children and often associated with high fevers.

Many nurses and medical professionals correlate high fevers with seizures. But what if I were to tell you that the high fever does not actually cause the seizure, or at least, not alone?

The true “trigger” of the seizures seems to a rapid rise in temperature, with high fevers lowering the seizure threshold. Yes, the higher the fever the more likely the seizure will occur, but the trigger seems to be the rapid rise in temperature instead of the fever itself.

Fevers can also lead to insensible water losses, dehydration, and hyponatremia, which all contribute to lowering the seizure threshold as well.

Often febrile seizures accompany viral infections and can even occur after certain vaccinations. The good thing is these febrile seizures are brief and usually have no long-lasting effects.

And speaking of fevers – you don’t always need to treat them! Sure – high fevers can be treated to alleviate symptoms and prevent dehydration. Treating high fevers >102 may even help prevent febrile seizures in young children.

But remember, there is some utility in not treating fevers, especially low-grade as this is a natural defense mechanism that your body uses to fight the infection. So if the patient can stay hydrated – an antipyretic is not always absolutely necessary.

7. Pseudoseizures are Faking It!

Speaking of seizures – sometimes patients have a “seizure” and.. well.. we don’t believe them. These are termed pseudoseizures – because they aren’t real seizures.

Now – not all seizures are the classic tonic-clonic Grand Mal seizure, but sometimes people really do have “fake seizures”. But does that mean they are faking it?

Nursing Myth -PseudoseizureMaybe not! Those with a significant history of psychological disorders, a history of trauma, and poor coping mechanisms can have what’s called “Psychogenic nonepileptic seizures”. These are often psychosomatic and the patient may not realize that they are indeed not true seizures.

Now, do some people actually fake it? Sure – they might do it for attention or to get out of a DUI (yeah… it happens).

But just because someone is having a “fake seizure” doesn’t mean that it’s fake for them. Although it may seem difficult at times – try to maintain compassion and understanding, even when it might seem like they’re wasting your time.

Related Content: 10 Nursing Hacks Every ER Nurse Should Know

8. Flu Shots Cause the Flu

While this one seems pretty basic – I’m a little dismayed by how many RNs that I know personally and professionally seem to perpetuate this nursing myth.

There is no possible way that the flu shot can cause the flu. Let me repeat that – there is NO possible way that the flu shot can cause the flu.

The IM Flu vaccinations contain inactivated virus or a viral protein, both of which cannot replicate or cause disease. It is physically impossible for them to cause influenza.

However, common side effects after the injection include local site reaction, body aches, low-grade fevers, nausea, and fatigue. These are short-lived and probably represent your immune system creating antibodies.

If you do actually get full-blown flu shortly after the vaccination, there are multiple explanations:

  • You were exposed before the shot
  • You were exposed before you created significant antibodies, which takes about 2 weeks from the date of vaccination
  • You were infected with a strain that the vaccination didn’t cover
  • You were infected with a strain that the vaccine did cover, but you still developed illness. This illness was likely less severe than it would have been without the vaccination.

While not nearly as common, a live-attenuated flu vaccination can be given, but this is intranasal and not via intramuscular injection. This technically can cause the flu, although unlikely to call full-blown illness.

The flu vaccination is always recommended for healthcare providers, as the flu kills between 12-60K people in the US per year (meanwhile COVID has claimed over 300K within the last 6 months… but it’s “just the flu” I guess).

Nursing Myth - Flu Vaccines

9. Vancomycin Broad-spectrum?

Vancomycin is a “heavy-hitter” antibiotic that we commonly give within the hospitals for MRSA infections. Because of this, it is commonly considered broad-spectrum. However, Vancomycin is actually pretty narrow-spectrum.

The term “broad-spectrum” indicates that the antibiotic has a wide range of bacteria that it can kill. This includes gram-positive organisms, gram-negative organisms, aerobes, and/or anaerobes.

Vancomycin works wonders for gram-positive organisms, but that’s really it. Yes, this includes MRSA, but it doesn’t really have any activity against gram-negative organisms. Because of this, it is actually a narrow-spectrum antibiotic. This is why you will usually see this ordered with another antibiotic at the same time. But why does this even matter?

In sepsis, it is important to give antibiotics STAT, and it’s recommended that you give the broad-spectrum antibiotic first. This ensures that antibiotics that are more likely to cover the bacteria are given in a timely manner.

Vancomycin can take a while to infuse (1-2 hours), and a broad-spectrum antibiotic like Zosyn or Cefepime should have been given first and infuses quickly (over about 30 minutes).

Related Content: 6 Steps for Sepsis Management

10. Toradol Works Better than Ibuprofen

Toradol is an IV or IM medication that we commonly give within the ED and inpatient settings. It’s an injection form of an NSAID, and due to this I tell my patients “it’s like IV ibuprofen”.

Since it is an NSAID, it does decrease inflammation, help with pain, as well as reduce fever. Toradol tends to work great for migraines, kidney pain, arthritic/orthopedic pain, etc.

Since given via IM injection or via IV, most people automatically assume it will work better than a pill. This isn’t poor logic either as many medications work better when given intravascularly as they essentially have 100% bioavailability and do not undergo the “first-pass effect” through the liver.

Interestingly enough, studies do not show that IV/IM Toradol is any more effective at reducing pain than PO ibuprofen.

There also appears to be a ceiling dose of Toradol for pain, which is about 10mg IV. This means that a 30mg IV Toradol injection is no more effective at alleviating pain than a 15mg injection.

Don’t forget that NSAIDs inhibit prostaglandin synthesis. These prostaglandins are important in protecting your stomach as well as maintaining perfusion to your kidneys. This is why too much NSAID, whether PO or IV, should be avoided in those with a history of PUD, upper GI bleed, or kidney disease.

Nursing Myth -Toradol better than ibuprofen

Related Content: Opioid Alternative Analgesics in the ER

11. Normal Saline Always Helps Hyponatremia

When a patient’s sodium level is low (<135 mEq/L), called hyponatremia – this is often due to dehydration. A simple treatment is to give them Normal Saline which usually does improve their sodium levels. And this is the most common cause of mild hyponatremia = dehydration.

But it’s not always that simple. Sodium is a complicated electrolyte that can be influenced by many different factors. To simplify the treatment of hyponatremia, it depends on fluid status:

  • Hypovolemic: Give Fluids (NS)
  • Hypervolemic: Restrict Fluids and give diuretic like lasix
  • Euvolemic: Do not give fluids and consider SIADH as a cause

Serum osmolality is often taken into account, and urine electrolytes/osmolarity can also help. It is not always this easy, and a nephrologist can help determine the cause and treatment.

In general, if you see mild decreases in sodium with elevations in renal function and a history that is consistent with decreased PO intake or possible dehydration – you won’t go wrong administering a 500-1000mL bolus followed by a slower maintenance rate and following the labwork.

Remember that sodium levels should always be corrected SLOWLY, with a goal correction of about 4-6mEq/day, and no more than 8 mEq/day. If corrected too quickly, this can cause irreversible brain damage called Osmotic Demyelination Syndrome.

Don’t forget that high glucose elevations will falsely lower the sodium level! You can use a calculator to make the correction here!

Related Content: Intravenous Fluids Breakdown

12. Respiratory Rate Isn’t Important

One of the 5 vital signs is the respiratory rate (don’t get me started on the 6th vital sign). For some reason, it has become commonplace to not count respirations and simply chart “16-18”.

Why is this done? Well first off, nurses and nurse’s aides are busy, and sitting and counting for 30-60 minutes just seems like a waste of time. This is reinforced when the patient appears well, is non-toxic appearing, and has nothing respiratory going on.

Honestly – I get it. When I was a floor nurse I did the same thing. But sometimes it is especially important to count respirations, even when you might not realize it.

When I was a new nurse on a Med-Surg floor, I had a patient who I took over at 11 pm. I knew something didn’t look right with her, but I wasn’t quite sure what. She had a flushed face and was breathing about 30 rpm, but she denied any symptoms and her vital signs were fine – at least the ones we actually checked.

Long story short – in the morning she was found to have been in severe metabolic acidosis secondary to renal failure, with a pH of 7.1. Her increased respiratory rate was actually respiratory compensation to try and breathe off some CO2 to compensate for her acidosis. So even though she had “nothing respiratory” going on, it was still an important vital sign that I should not have overlooked.

Please be mindful to count accurate respiratory rates on people who are breathing fast or have any type of respiratory complaint, especially with COVID.

Best practice is to count respirations for a full minute since respiration patterns tend to fairly irregular. However, any counting is better than none. You can count for 10 seconds and multiply by 6, count for 15 seconds and multiply by 4, count for 20 seconds and multiply by 3, or count for 30 seconds and multiply by 2. The longer you count, the more accurate the rate will be.

Nursing Myth - Respirations

Related Content: 5 Vital Sign Errors to Avoid

13. Don’t Let Concussions Sleep

After mild-to-moderate trauma to the head, many people develop concussions. This is a common presentation to the ED. There is a running myth that those with concussions should not be allowed to sleep as “they may never wake up”.

When my brother was in high school he was a baseball pitcher, and he got hit in the head and suffered a pretty significant head injury. I vividly remember trying to keep him awake in the backseat for fear of him “not waking back up”. Now, this might not be a great example because he did end up having a subdural hematoma… but regardless – keeping someone awake won’t really help them.

The worry is thought someone who falls asleep and actually has a brain bleed will die in their sleep if no one checks on them. Since they are sleeping, no one will recognize their decreased neurologic status.

While this could happen, it is unlikely to occur from a concussion. However – it is important that patients be evaluated by medical professionals and have a neurological exam and possibly a CT of the head.

Those who should get a CT of the head include:

  • Nursing Myth - ConcussionGlasgow Coma Scale <15 or any neuro deficit
  • Suspected skull fracture
  • >1 episode of vomiting or seizures
  • >65 years old or anticoagulant use
  • Amnesia
  • Dangerous mechanisms (like a pedestrian hit by a car)

If you are discharging a patient who had a CT of the head which did not show any bleed, there is no indication for them to “stay awake” or be checked on throughout the night, as you’ve essentially ruled out a head bleed.

Yes, delayed bleeds can occur but this is not likely to happen in those at low-risk with concussions. If they are cleared for discharge, they should be encouraged to rest as this will help them to heal.

Related Content: The Cranial Nerve Assessment for Nurses

And those are the 13 nursing myths that you probably fell for, or at least maybe you fell for one or two! Don’t let these nursing myths be perpetuated, as we should always strive for accurate and excellent education of nursing professionals!

Are there any other nursing myths I didn’t mention? Leave them below in the comments!



Geisinger Medical Lab Specimen Collection Manual and Test Catalog

Hemolysis: What is it and how to prevent it

How Long can we Store Blood Samples: A Systematic Review and Meta-Analysis (2017)

Morphine and Oxygen in Heart Attacks

Overview of the acute management of ST-elevation myocardial infarction (UTD)

Oxygen therapy in acute coronary syndrome: are the benefits worth the risk? (2013)

Air Versus Oxygen in ST-Segment-Elevation Myocardial Infarction (2015)


The Nose Knows Not: Poor Predictive Value of Stool Sample Odor for Detection of Clostridium difficile (2013)

AMA Insurance Coverage

Know Your Rights: Understanding Hospital Discharge Against Medical Advice

Financial Responsibility of Hospitalized Patients Who Left Against Medical Advice: Medical Urban Legend? (2012)

Febrile Seizures

Clinical features and evaluation of febrile seizures (UTD)

Febrile Seizures Fact Sheet


Psychogenic nonepileptic seizures (UTD)

Psychogenic nonepileptic seizure (Wikem)

Influenza Vaccine

Misconceptions about Seasonal Flu and Flu Vaccines (CDC).

Seasonal Flu Shot (CDC)

Seasonal influenza vaccination in adults (UTD)

Toradol vs Ibuprofen

Intramuscular ketorolac vs oral ibuprofen in emergency department patients with acute pain (1998)

Myth: Parenteral ketorolac provides more effective analgesia than oral ibuprofen (2007)


Overview of the treatment of hyponatremia in adults






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