Fever and night sweats after hip or knee replacement

If you feel feverish, chilled, or wake with damp clothing or bedding, check your temperature with a working digital thermometer. Record the number, time, measurement method, recent acetaminophen or anti-inflammatory medicine, and whether symptoms are improving or recurring. A sweat episode by itself is not proof of infection, and feeling warm is not the same as a measured fever.

Your discharge instructions should state when to call. Follow that threshold and contact pathway because protocols vary with the procedure, medical history, and time since surgery. If the instructions are unavailable, call the surgical team rather than waiting several days or choosing your own cutoff.

Surgery activates an inflammatory response as tissues heal. During the first days, that response can cause a temporary temperature rise even when there is no infection. A study of patients after total hip or knee arthroplasty found that postoperative fever occurs in both groups and emphasized interpreting it with the clinical picture. Review the total-joint-arthroplasty fever study.

That does not make every fever “normal.” Timing, height, recurrence, associated symptoms, and whether recovery is otherwise moving forward all matter. Fever that begins later, persists, repeatedly returns, or appears with a new localizing symptom deserves more attention than a single early reading in an otherwise improving patient.

Night sweats may mean the room or bedding is too warm, but sweating can also accompany fever, infection, pain, anxiety, low blood sugar, medication effects, or withdrawal from certain medicines. MedlinePlus lists fever, infection, medicines, warm temperatures, low blood sugar, and withdrawal among possible causes of excessive sweating. Review the MedlinePlus sweating overview.

Describe the episode precisely. Was the pillow slightly damp, or were clothes and sheets soaked? Did you have shaking chills, a measured temperature, confusion, palpitations, low blood sugar symptoms, worsening pain, or new wound changes? Repeated drenching sweats carry more information than a vague sense of being warm.

When deciding what evaluation is useful, clinicians consider how many days have passed since surgery, the highest measured temperature, whether there are repeated spikes, and whether symptoms point to a source. A large joint-replacement study found that higher temperatures, fever after postoperative day three, multiple fever spikes, and revision surgery were among the circumstances in which a diagnostic workup was more likely to be useful. Read the PubMed abstract.

This evidence guides clinicians; it is not a home rule for ignoring an early fever. A new wound problem, breathing symptom, urinary symptom, severe calf change, or rapidly worsening condition can require evaluation at any time.

Contact the surgical team promptly for increasing redness, spreading warmth, new or increasing drainage, wound opening, worsening swelling, escalating joint pain, or a sudden decline in walking or function—especially when any of these occur with fever, chills, or sweats. Do not remove a sealed dressing merely to inspect underneath unless your care instructions say to do so.

AAHKS advises watching for persistent joint pain with swelling, warmth, drainage, or redness, with or without fever, chills, or sweats. Review the AAHKS infection guidance. The JRH wound-management guide explains dressing and incision warning signs in more detail.

A fever after surgery may come from the respiratory tract, urinary tract, skin, gastrointestinal system, IV site, or another source unrelated to the implant. Report cough, worsening shortness of breath, chest pain with breathing, sore throat, burning urination, urgency, foul or cloudy urine together with symptoms, flank pain, vomiting, diarrhea, abdominal pain, or a new rash.

Urinary retention and catheter use can complicate early recovery, so reduced urination, bladder pressure, painful urination, or fever with urinary symptoms should be reported. The JRH urinary-retention guide reviews those warning signs. Do not assume every postoperative fever comes from the new joint.

Acetaminophen and anti-inflammatory medicines may temporarily lower a temperature, so tell the team what you took and when. Opioids, antidepressants, thyroid medicine, medicines used for nausea, and other drugs can affect sweating or temperature regulation. A medication list is more useful than guessing which one is responsible.

Do not stop a prescribed opioid abruptly or change the schedule without guidance. MedlinePlus notes that suddenly stopping morphine can cause symptoms including sweating, chills, restlessness, nausea, diarrhea, and a fast heartbeat. Review the MedlinePlus morphine information. Similar symptoms can also have more serious causes, so medication withdrawal should not be self-diagnosed.

Hawaiʻi weather, a warm bedroom, thick bedding, dehydration, poor intake, vomiting, or low blood sugar can contribute to sweating and weakness. Move to a comfortable room temperature, use light bedding, and follow the fluid and nutrition plan provided by the care team. If you have diabetes, follow the glucose-monitoring and sick-day plan.

Do not force large amounts of water, salt, or electrolyte products. That can be unsafe with heart or kidney disease, fluid restrictions, or abnormal sodium levels. If sweating occurs with confusion, fainting, inability to drink, repeated vomiting, very low urine output, or an abnormal glucose reading that does not respond to the prescribed plan, seek prompt medical advice.

Rest in a safe seated or lying position, check the temperature again only as directed, and gather the discharge paperwork and medication list. Note the incision appearance without disturbing the dressing, recent urine output, breathing symptoms, calf changes, and whether you can walk as expected. Keep someone nearby if you feel faint, weak, or confused.

Do not take leftover antibiotics, share another person’s medicine, or apply heat to a hot, red, swollen joint. Antibiotics can cause side effects, interact with other medicines, and make later testing harder to interpret. The correct treatment depends on the source.

Not every early temperature rise requires every possible test. A prospective study of early postoperative fever found that bedside assessment had the highest value and that routine cultures and chest imaging had little benefit in otherwise uncomplicated elective-surgery patients without a concerning source. Review the prospective study.

Symptom-guided care is not the same as “do nothing.” The team may recommend an examination, wound review, blood tests, urine testing, chest evaluation, imaging, joint aspiration, or another study based on the timing and symptom cluster. Call first unless the condition is clearly an emergency.

Use the postoperative number or same-day medical evaluation for a measured fever at or above the threshold in your discharge instructions; fever that persists or repeatedly returns; fever beginning after the first few postoperative days; shaking chills or drenching sweats; a worsening overall trend; or concern that medicine is masking the temperature.

Also call promptly when fever or sweats occur with increasing wound drainage, spreading redness, increasing joint warmth or swelling, worsening pain, new urinary symptoms, persistent cough, calf pain or one-sided swelling, repeated vomiting, inability to keep fluids or essential medicines down, or a new decline in walking or alertness.

Call 911 or seek emergency care for severe trouble breathing, chest pain, blue or gray lips, coughing blood, fainting, new confusion, inability to wake normally, signs of stroke, a rapidly spreading rash with breathing or facial swelling, or severe and rapidly worsening illness. A hot swollen calf with sudden shortness of breath or chest pain can signal a blood clot traveling to the lungs.

The JRH blood-clot prevention guide reviews clot warning signs. Do not drive yourself when faint, confused, severely short of breath, or otherwise unstable.

When calling, be ready to report:

Keep a thermometer, medication list, after-hours number, and local urgent-care or emergency plan ready before surgery. If you are recovering away from Oʻahu, know where you can receive laboratory testing, imaging, and emergency assessment without first boarding a flight.

Do not begin inter-island travel or a long drive with unresolved fever, shaking chills, drenching sweats, new wound drainage, worsening redness, breathing symptoms, significant calf changes, confusion, or rapidly worsening illness. Contact the surgical team and arrange care where you are.

A brief early temperature rise or isolated sweat episode can have a noninfectious explanation, but no single symptom can rule infection in or out. The safest approach is to measure rather than guess, record the pattern, check for localizing symptoms, and follow the discharge instructions.

If you are preparing for hip or knee replacement and want a recovery plan that accounts for medicines, diabetes, prior infection, travel, or home support, schedule an orthopedic consultation.

• Characteristics and risk factors of fever after total joint arthroplasty
• Routine workup of postoperative pyrexia following total joint arthroplasty
• Early postoperative fever and the routine fever work-up
• AAHKS: Infection and your joint replacement
• MedlinePlus: Sweating
• MedlinePlus: Morphine
• MedlinePlus: Fever