When I was a student I remember hearing medical terms all the time that would make me think, “I should probably know what that means, but I’m too embarrassed to ask.” You’d think that would go away after more than ten years at the bedside, but it doesn’t…there is ALWAYS going to be something you don’t know. 

And while it’s perfectly normal to feel hesitant when it comes to broadcasting your lack of knowledge, I want you to know it is 100% always okay to ask questions. If you are EVER in doubt about an assessment finding, a medication, a procedure, or anything going on with your patient, it is up to you to set your pride aside and ASK. And if it’s something that’s not urgent, simply make note of it and look it up later. This is a great way to grow your clinical knowledge and boost your confidence. 

Now let’s dive into some common medical terms that students (and even experienced nurses) often feel a little unsure about.

Drill this information in by listening to episode 236 of the Straight A Nursing podcast wherever you get your podcasts or straight from the website here.

This vs. That

Objective vs. subjective – An easy way to remember this is that objective means something that can be observed, while subjective means something the “subject” experiences. This is exactly what we’re talking about when we refer to “signs and symptoms.” Objective data are the signs and subjective data are the symptoms. So, when someone says “signs and symptoms” you’ll know this means both information obtained from assessing the patient and information obtained by asking the patient about their experience.

Sensitivity vs. specificity – These are both measures of a test’s accuracy. Sensitivity is the test’s ability to correctly determine a positive result in individuals with the disease. You may also hear this referred to as the “true positive rate.” A highly sensitive test will therefore have very few false negative results. In other words, if the test is negative, you can believe it’s negative.

A false negative result is when the test is negative, but the individual actually does have the disease. The risk with a false negative is the patient not getting appropriate treatment in a timely manner. 

An easy way to remember sensitivity is with the mnemonic SnNout: When a highly sensitive test (Sn) is negative (N), this helps us rule out the disease (out).

An example of a high sensitivity test is the D-dimer used to rule out the presence of a DVT. When used in patients with low or moderate probability for a blood clot, a negative D-dimer is not likely to be a false negative. In other words, we can believe the negative result because the test is very sensitive…a negative D-dimer likely means this individual does not have a blood clot. 

Specificity refers to the test’s ability to correctly identify a negative result, so you may hear it referred to as the “true negative rate.” Tests that are highly specific will have very few false positive results. In other words, if the test is positive, you can believe it.

A false positive result is when the individual does not have the disease, but the test says they do. The risk here is individuals receiving treatment they do not need. 

An easy way to remember specificity is with the mnemonic SpPin: When a highly specific test (Sp) is positive (P), this helps us diagnose or rule in the disease (in).

An example of a test with high specificity is the nitrate dipstick test that is used to identify UTI. If the test is positive, the individual very likely has a UTI and antibiotics may be ordered.

Idiopathic vs. iatrogenic – An idiopathic disease is one without an identifiable cause. Examples are idiopathic pulmonary fibrosis and idiopathic thrombocytopenia purpura (ITP). 

Iatrogenic refers to conditions that are a result of medical treatment such as ventilator-acquired  pneumonia or leukemia secondary to radiation or chemotherapy.

Ischemia vs. infarction vs. necrosis – You’ll hear these terms used a lot when discussing stroke, acute coronary syndrome and myocardial infarction though it’s important to note that any tissue can be affected. 

Ischemia refers to tissue that has inadequate blood supply (and therefore inadequate oxygen). This is what is happening in angina pectoris. 

Infarction refers to an area of tissue that has no blood supply at all and the tissue dies as a result. The “infarcted area” is the area of dead tissue. 

Necrosis is simply another term for dead tissue.

Inflammation vs. infectionInflammation is a protective mechanism in the body that occurs in response to injury, irritant or infection. The classic signs of inflammation are pain, reduced mobility, redness, swelling and heat.

Infection is the presence of an invading pathogen such as a virus or bacteria. Infection can cause inflammation, but inflammation does not cause infection. However, it is important to note that chronic inflammation can contribute to a wide range of chronic conditions such as heart disease. 

Urinalysis vs. urine culture – A urinalysis is a general test that looks at the physical, chemical and microscopical characteristics of the urine. This includes color, clarity, odor, specific gravity and pH. It also detects the presence of multiple elements such as protein, WBCs, RBCs, casts, glucose, and leukocyte esterase. 

A urinalysis is often used as the first step in determining if the patient has a UTI. If certain elements are present (such as WBCs or leukocyte esterase), this indicates UTI is likely and the urine is then cultured. 

The urine culture & sensitivity (C&S) looks at the specifics of the pathogen that is causing the UTI. With this test, we can learn what pathogens are causing the infection and which antibiotics it is susceptible to. A urinalysis will result quickly, while a urine culture & sensitivity will take at least 24 hours.

Hypoxia vs. hypoxemia – These terms are often used interchangeably though they actually mean two different things. Hypoxia refers to a low oxygen level in the tissues and is measured via pulse oximetry (SpO2 < 90%). Hypoxemia is a low oxygen level in arterial blood and is measured via an arterial blood gas analysis (PaO2 < 80mmHg). What gets many people mixed up is these conditions are different AND do not always occur simultaneously. A patient can have hypoxemia without hypoxia if the body has had time and the ability to utilize compensatory mechanisms. Conversely, the patient can have hypoxia (low level in the tissues) without hypoxemia (low level in the blood) if the cells aren’t able to utilize oxygen effectively. This concept is slightly more advanced, so feel free to dive into more details about oxygenation here.

Arrhythmia vs. dysrhythmia vs. aberrancy – The good news here is that arrhythmia and dysrhythmia refer to the same thing…an abnormal or irregular heart beat. Examples are atrial fibrillation, bradycardia and ventricular tachycardia.

Aberrancy is an abnormality in the electrical conduction through the ventricles resulting in a wider-than-normal QRS. Think of it as the electrical signal taking the side streets instead of the freeway. It still gets where it intended, it just took a longer route. In many cases, because of the wide QRS, aberrancy looks like a ventricular rhythm so careful identification is absolutely vital.

Crystalloid vs. colloid – When your patient is hemodynamically unstable or volume depleted, you’ll hear these terms used to describe the type of fluids they’ll receive. Crystalloids refer to fluids that have small molecules and provide immediate volume to the vascular space. These fluids can shift easily into the interstitial space, especially when the vasculature is permeable, such as in sepsis. Examples of crystalloids are 0.9% sodium chloride (“normal saline”) and Lactated Ringers. 

Colloids, on the other hand, have larger molecules and increase oncotic pressure to pull fluid into the vascular space. Commonly used colloids are dextran, FFP, and albumin. If you see that your patient has furosemide and albumin ordered, make sure you read the administration orders carefully. The MD most likely wants the albumin given first, which will pull excess fluid into the intravascular space. This is followed by administration of the diuretic, which then removes the excess fluid from the body.

Suction vs. water seal – A chest tube may be ordered to wall suction or water seal. What does this mean? Suction means the chest tube draining system is connected to the wall suction regulator which provides continuous suction to the device (the amount of suction is regulated at the device). 

A chest tube ordered to be set to “water seal” simply means it is not attached to wall suction at all. Instead, the water in the water chamber acts as a “seal” to prevent air from entering the pleural space when the patient inhales. Your orders will specify how the MD wants the chest tube drainage system set up.

Rales vs crackles vs rhonchi– You will hear the terms rales and crackles a lot, and guess what? They’re actually the same thing! Fine crackles (or rales) are often a result of atelectasis and coarse crackles are commonly associated with conditions such as aspiration and pulmonary edema. 

You may hear the lung sounds described as “wet” especially if the patient has pulmonary edema or ARDS, as in “I’m concerned about Mr. Reynolds. His lungs sounds are wet and his urine output has decreased.”

Rhonchi are low-pitched breath sounds that are often compared to a snoring sound. Rhonchi can be heard on both inspiration and expiration, and are most likely to be heard in the large airways. A common cause of rhonchi is airway obstruction due to the thick mucus that is present in cystic fibrosis.

General medical terms that you might not (yet) know

In this section I’ll briefly describe some common medical language you’re likely to hear in the clinical setting. Understanding what others are discussing plays a huge role in boosting your confidence and your ability to put the pieces together when assessing your patient and anticipating their needs.

Refractory – When someone says the patient’s condition is “refractory” what they mean is it is not improving despite treatment. For example, “refractive hypoxia” means the SpO2 continues to be low even though we’ve applied oxygen. “Refractive hypotension” means the patient remains hypotensive even after we’ve given fluids or vasopressors (common in septic shock).

Residuals – If someone asks you about the patient’s “residuals” they’re referring to the amount of tube feeding in their stomach. Yes, this involves pulling back on the NGT to measure how much formula is sitting in the stomach. If the residuals are above a certain amount, this indicates the patient has impaired or slow gastric motility. The patient may have feedings held and receive a medication such as metoclopramide.

White out – This term is used to describe an especially ominous chest x-ray which shows a lot of white where you would expect to see black. The white color is often cloud-like in appearance but can appear opaque. It occurs in multiple cases such as pleural effusion and acute respiratory distress syndrome (ARDS). 

The gap – When someone on the health care team refers to “the gap” they’re not talking about going shopping. They’re referring to the anion gap which is a diagnostic calculation commonly used in diabetic ketoacidosis. When the gap is “closed,” and other measurements are within normal range (pH, bicarbonate and blood glucose), the DKA is considered to be resolved.

Titrate – This is a term used to describe lowering and increasing a medication dose based on the patient’s response to that medication. This is commonly done in the ICU with medications such as norepinephrine, which is titrated to maintain an ordered blood pressure range.

Let’s talk medical slang!

Nurses and other health care workers use a lot of medical slang. Here are some common terms you’ll hear in the clinical setting. 

A rainbow – This refers to a range of blood samples that involve using tubes of various colors. Typically this means you’re drawing a vial for CBC, a vial for coagulation studies (often just called “coags”) and another vial for chemistries. Where I work this means I’m grabbing a red tube, a blue tube and a green tube (a beautiful rainbow!).

Blunt – Usually this will refer to the needle that’s used to draw up medication into a syringe. It’s “blunt” and doesn’t have a sharp end for injection.

End cap – This refers to a sterile cap that is placed on a disconnected IV line. It is also sometimes used to refer to the needleless connector that is attached to the peripheral IV. The context in how it is used should help you understand which type of “end cap” is being discussed.

Dead ender – This is a type of end-cap that does not have an opening in it. When you first set up your arterial line pressure monitoring system, the cap that is in place has an opening in it. You want to replace that with a “dead ender” or a cap that truly closes off the system.

Christmas tree – The little adapter piece that connects to your oxygen valve at the wall is called a “Christmas tree.” This is due to its shape and the fact that it is often green. The real name for this device is a nut and nipple adaptor so you may hear it called that as well!

PureWick – These handy external urinary collection devices are becoming more commonplace, but in case you’ve never heard of it, you can learn all about them here. The short version is that it’s a way to minimize skin breakdown and the use of indwelling catheters in female patients. It kind of looks like a blue hot dog on a stick, tbh. 

Chux – A “chux” pad is an absorbent pad utilized to wick moisture away from patients who are incontinent while also keeping the linens clean. The word “chux” refers to an older brand that’s no longer available…but the name stuck around!

Snowing the patient – This refers to the practice of giving the patient enough medication to render them unconscious. We try to avoid doing this because of the detrimental effects of polypharmacy and immobility, especially in ventilated patients. If you’re interested in learning more about this topic, check out this bonus episode Decreasing ICU Delirium with Kali Dayton.

Going on a road trip – If one of the nurses says they’re “going on a road trip” there is a chance they’re packing their car for a much-needed getaway. However, there’s a much bigger chance they’re taking their critically ill patient to some kind of procedure or test. 

So there you have it, some common medical terms, phrases and slang that often leave students and new nurses feeling a little bit lost. Are there other slang terms or medical terminology that you hear used frequently but don’t want to ask about? I won’t judge you!


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