Chills after surgery without a fever: what is normal and when to call
Chills after surgery without a fever are common, especially in the first day or two, when anesthesia, inflammation, pain, a cool room and blood loss can all make you shiver. Chills can also come just before a fever rises, so recheck your temperature. Call your surgeon for a reading above 100.4 °F (38 °C), shaking chills, or chills that start several days after surgery.
Is it normal to have chills after surgery?
Yes, in many cases. A StatPearls review of postoperative fever, published by the US National Library of Medicine, explains that shivering after surgery can come from anesthesia, cooling of the core, inflammation, pain or drug effects, and can range from a mild tremor to strong chills. Our main guide on why you feel cold after surgery covers the anesthesia side in detail.
Surgery itself sets off an inflammatory response. The same review notes that chemical messengers released by tissue injury can reset the body's temperature set point, which is why people can shiver while their temperature is normal or still rising. MedlinePlus adds that chills often come before a fever, as the body works to raise its temperature.
Why do I have chills after surgery but no fever?
Several ordinary causes can produce a chilled, shivery feeling without a raised temperature. They often overlap, and the timing is a useful clue.
| When | Common reasons for chills without fever | What usually helps |
|---|---|---|
| First hours | Anesthesia wearing off, a cool recovery room, IV fluids, pain | Warm blankets, pain control, telling the nurse you feel cold |
| Days 1 to 2 | Inflammation from the surgery itself, poor sleep, low food and fluid intake | Layers, rest, fluids as your team allows, checking temperature |
| Days 3 and later | Blood loss or anemia, less movement, a cool home; infection becomes more likely | Temperature checks, wound checks, calling your surgeon if chills persist |
Can anemia or blood loss cause chills after surgery?
It can add to them. MedlinePlus notes that anemia, a low level of red blood cells, can make you feel tired, cold and dizzy, and anemia is common after operations with significant blood loss. If you feel cold along with unusual tiredness, breathlessness on mild effort or a racing heart, mention it to your care team, since a simple blood test can check your levels.
Pain, missed meals and broken sleep also lower your tolerance for cold. These causes tend to improve steadily as you recover rather than come and go in waves.
What does it mean to have chills 3 days after surgery?
Timing changes the picture. The StatPearls review explains that fever in the first 48 to 72 hours is usually noninfectious, while fever starting after 96 hours (4 days) is increasingly likely to signal an infection, and fever that persists beyond days 4 to 5 may mean an infection is developing.
New chills several days after surgery deserve more attention than chills on day one, even if the thermometer still reads normal. MedlinePlus lists fever and chills among the signs of a surgical wound infection, along with redness, warmth, pain, pus or drainage and a bad smell, and notes that most wound infections appear within 30 days. Call your surgeon if chills start late or keep returning.
Early on, a mildly raised temperature is not always a sign of infection either. StatPearls notes that a low-grade temperature up to 101.5 °F (38.6 °C) in the first 48 to 72 hours after routine surgery typically reflects normal healing, while stressing that the type of surgery, age and health history change what counts as normal. Your own discharge instructions take priority: if they give a lower number to call about, use theirs.
What are rigors after surgery, and how are they different?
Rigors are intense, uncontrollable shaking chills, often with chattering teeth, that can last for minutes even under blankets. They usually signal that the body is driving its temperature up quickly. The StatPearls review lists chills and rigors as part of the fever response.
Mild shivering that settles with a blanket is common. Rigors are different: take them as a reason to check your temperature and contact your surgical team the same day, or seek urgent care if you feel very unwell.
How to stay comfortable and keep track at home
Comfort and monitoring go together, so you can spot a pattern early.
Use a reliable thermometer and write down the reading and time whenever you feel chilled.
Note when you last took any fever-reducing pain medicine, since it can lower a reading.
Keep the room comfortably warm, wear socks and a soft layer you can open for wound checks, and get up and move as your team advises.
Dress in light layers you can add or remove; MedlinePlus advises against heavy bundling when you have a fever.
Avoid heating pads, hot water bottles and heat packs on or near the incision. Skin near a surgical site can be numb, and a review in the journal Wounds found that people with reduced sensation after procedures such as abdominoplasty or breast reconstruction are at higher risk of burns.
When to call a clinician or emergency services
Call your surgeon or care team promptly for any of the first three signs. Call emergency services for the last.
A temperature above 100.4 °F (38 °C), or chills that keep returning.
Shaking chills or rigors, especially if they start 3 or more days after surgery.
Redness, warmth, pain, pus, drainage or a bad smell from the wound (MedlinePlus).
Fever, shivering or feeling very cold together with confusion, clammy or sweaty skin, extreme pain, a fast heart rate or shortness of breath; the CDC lists these as signs of sepsis, a medical emergency.
Key takeaways
Chills without fever are common in the first day or two after surgery and often come from anesthesia, inflammation, pain and a cool room.
Chills can come before a fever rises, so recheck your temperature.
New chills 3 or more days after surgery deserve a call to your surgeon, even with a normal reading.
Rigors (uncontrollable shaking) and any reading above 100.4 °F (38 °C) are reasons to contact your team.
Keep heat packs and heating pads away from the incision, where skin may be numb.
Frequently asked questions
Is it normal to have chills after surgery but no fever?
Often, yes, especially in the first day or two. Anesthesia, inflammation, pain, blood loss and a cool room can all cause chills with a normal temperature. If chills are new several days later or keep returning, call your surgeon.
How long do chills last after surgery?
Shivering from anesthesia usually settles soon after you wake up and warm up. Mild chilliness from low energy or blood loss can linger during recovery but should steadily improve. Chills that worsen or appear later need a call to your care team.
Can pain medicine cause chills after surgery?
Drug effects are one of the recognized causes of shivering after surgery. Some medicines can also lower a fever reading and hide a rising temperature. Do not stop or change any medicine on your own; talk to your prescriber or surgical team.
Why do I feel cold but my temperature is normal after surgery?
Your body's temperature set point can shift with inflammation, so you feel cold while your temperature is normal or still rising. Blood loss, tiredness and low food intake also make you feel colder. Recheck your temperature later and note the pattern.
Should I go to the ER for chills after surgery?
Go to emergency care if chills come with confusion, shortness of breath, a fast heart rate, clammy skin or severe pain, which can be signs of sepsis. For chills with a fever or wound changes, call your surgeon promptly.
From HEATJAC
We design low-profile thermal garments: a heat-reflective vest and a thermal harness with pockets for warmers or cold packs. If you have reduced sensation or a health condition, check with your clinician before adding heat.
Choosing gear? Before you buy: a checklist for any warming garment · Are heated vests safe?
Related reading
why you feel cold after surgery, and shivering after anesthesia
perioperative hypothermia and patient warming: the complete guide
Sources
Postoperative Fever (Azmat and Martingano), StatPearls, NCBI Bookshelf, US National Library of Medicine
Chills, MedlinePlus, US National Library of Medicine
Surgical wound infection: treatment, MedlinePlus, US National Library of Medicine
Anemia, MedlinePlus, US National Library of Medicine
About Sepsis, Centers for Disease Control and Prevention
Burns Sustained From Body Heating Devices: An Integrative Review (Kornhaber et al., Wounds, 2020), Wounds / HMP Global Learning Network
About HEATJAC. HEATJAC is a thermal architecture company founded by an anesthesiologist. We design patented garment systems that capture, conduct and broaden warmth across the body, and we publish this knowledge hub because the science of staying warm should be public. HEATJAC products are not medical devices and are not intended to diagnose, treat, cure or prevent any disease.