When writing your care plans or taking care of patient’s who’ve had surgery, you are going to be watching them like a hawk for any signs of potential complications. Some of those complications will be subtle, but thankfully the body is pretty adept at giving you clues. One of those clues you’ll see is fever. 

What are the causes of post-op fever AND, what are going to do about it?

Thankfully, the five most common causes of post-op fever can be remembered easily with the 5 Ws. Wind, water, walking, wound, wonder drug. Ok, now that we got that out of the way…what does all this mean? Wind and water? What does any of this have to do with surgery?

Wind = lungs

After surgery, patients are still groggy from the anesthesia and usually they’re in a fair amount of pain. Both of these things contribute to patients just not wanting to take full, deep breaths or get out of bed and move around. And what happens when patients don’t take full deep breaths or exercise those lungs? Atelectasis AND pneumonia. Yikes!

As you will learn in your Med/Surg course, getting out of bed after surgery is THE MOST IMPORTANT THING your patients can do. Even open-heart patients typically get OUT OF BED and sit in the chair the morning after their surgeries. If someone whose chest was cracked and forcibly held open with medieval looking instruments can get out of bed, your patient with the laparoscopic appendectomy can get out of bed (just saying….and I am guilty of this! I was the BIGGEST baby when I had my appy…I was a terrible patient, but this was pre-nursing, so I’m forgiven, right?)

Immobility, as you will learn, causes a lot of complications, including post-op respiratory compromise. If your patient has just a mild fever and mildly-decreased O2 saturation levels, take a listen to their lungs (don’t worry, you’ll learn how to do this)…if it sounds kind of “crackly” then it’s possible the patient has atelectasis (collapsed alveoli that make a little crackly sound when they expand open). Have your patient do a fair amount of deep breathing and it’s possible the atelectasis can clear, resolving your post-op fever. 

However, a fever could be a more ominous sign of a more serious complication…post-op pneumonia. If your patient has a fever, dropping O2 saturation levels and an elevated white count, it might be a good idea to ask the MD if she’d like a chest x-ray. Typically, these lung-related fevers occur within 48-hrs of surgery, so be watchful!

Water = UTI

Now, let’s say it’s been a few days and your patient develops a fever. Another common cause of post-op fever is a urinary tract infection due to the catheter used during surgery. Even if the catheter comes out right away, it is still possible that bacteria was introduced into the urethra during insertion. If your patient currently has a Foley catheter, try to see if it can be removed asap since the best prevention of a UTI is simply no Foley at all! Plus, getting the patient up out of bed to the commode is good for them in so many ways (immobility = bad things, remember?). And, if the catheter is in place, doing meticulous “catheter-care” at least twice a day is essential to keeping those bacteria from getting in where they don’t belong. 

Walking = DVT

Studies show a correlation between deep vein thrombosis and fever, so if your post-op patient develops an elevated temp, it’s prudent to consider if it could be a DVT. Has your patient been mobilizing? Where was his surgery (some surgeries put patients at higher risk than others), is he on DVT prophylaxis (such as heparin or lovenox), is he wearing his SCDs, is he getting up and walking around? If the answer to any of these questions is no, then it could be possible that the cause of the fever is a DVT and should be mentioned to the MD so she can evaluate the patient thoroughly. The reason we worry so much about DVT is that the clots can break free from the location of origin and travel to the lungs where they cause pulmonary embolism, a very urgent, life-threatening condition. Yet again, another reason to get those post-op patients out of bed!

Wound = wound

Finally, an easy one! Take a look at that surgical site. Fresh out of surgery it should be pinkish, maybe even red initially but without warmth or purulent drainage. The edges should be well approximated (no big gaps) and it shouldn’t be causing your patient an out-of-control amount of pain. Yes, surgery hurts. But if you barely touch the incision and they scream in pain, something’s not right. Note that the surgical dressing is typically ONLY removed by the surgeon, so when she comes by to see the patient and take down that first dressing, get in there so you can see it, too! If the dressing is getting saturated with blood or pus, (especially with the presence of fever) it’s a good idea to call the doc. 

Note that a post-pop wound infection can occur at any time, even up to a week after surgery (maybe even longer, depending on your patient’s ability to heal). 

Wonder drug = drugs that can cause a fever

Ok, this one is a bit of a stretch, but since it’s 5 Ws and not 4Ws and 1 D, then we have “wonder” drugs. Some anesthetic agents used during surgery can cause patients to develop a post-op fever, as can blood products and any medication the patient could be allergic to (antibiotics, we’re looking at you!) 

Note that your patient could have a reaction to ANY medication given during their hospitalization, so keep this in mind ESPECIALLY when giving a new drug for the first time. It is always a good practice to keep a close eye on your patient when first-ever doses are given. If they start to have a reaction to something, you can stop the infusion (if it’s being administered slowly) and let the MD know STAT. 

Get this on audio in podcast episode 87.


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