Postoperative fever can be caused by various physiological and infectious etiologies. Physiological fever occurring in the first 48 hours is a normal inflammatory response to tissue injury from surgery. Common causes of fever include atelectasis and pneumonia within the first 48 hours, and wound, urine, or intra-abdominal infections between days 3-7. Deep vein thrombosis is also a potential cause after days 5-7. A thorough evaluation including physical exam, lab tests, and imaging is needed to identify the source and guide appropriate treatment.

1. Postoperative Fever
Ahikam DJ

2. Objectives
• Definition
• Causes
• Physiological fever
• 7 W’s
• Take home

3. Defintion
Elevation of body temperature to greater than
38.3C (100.4F) following a major surgical
procedure

4. Causes
Day 0-2
• Physiological
• Atelectasis
• Blood transfusion
• Thrombophlebitis
Days 3-5
• Wound infection
• Catheter
associated
infection
• Intra-abdominal
collection
• Pneumonia
Days 5-7
• DVT
• Anastamotic leak
Days >7
• Intra-abdominal
collection
• DVT
• Septicemia

5. Physiological fever
• Seen in first 48 hrs
• An inflammatory response to the cytokines
released from tissue injury
• Act centrally and raise the thermoregulatory
set point for body temperature.
• Prevalence??

6. ‘Wind’
• Atelectasis (<48hr) and Pneumonia (>48hr)
• Cause: poor inspiratory effort, failure to clear
secretions
• Signs and symptoms: Decreased breath
sounds, crackles, tachypnea, dyspnea, cough,
hypoxemia, dependant infiltrates on chest x-
ray
• Rx: Incentive spirometry, chest physiotherapy,
early mobilization, bronchodilators.

7. ‘Water’
• Symptoms: fever, suprapubic/flank pain, renal
anger tenderness, urinary urgency
• Risk factors: longer duration of
catheterisation, unsterile placement, female
sex, older age, diabetic, history of previous UTI
• Urinalysis and urine culture with sensitivity
• Causative organism: E. Coli, Enterococcus,

8. ‘Wound’
• SSI: Infections that occur at or near the
surgical incision within 30 days of surgery or
with 90 days if prosthetic materials have been
implanted
• Erythema, warmth, tenderness, purulent
drainage from incision
• Superifical, Deep, Organ/space infection
• Organisms: Streptococcus, staph,
enterococcus

9. ‘Walking’
• DVT: Immobilisation
• Risk factors: abdomino-pelvic surgery,
orthopedic surgery, major trauma, spinal cord
injury, cancer, obese.
• Fever, calf tenderness
• Complication: Pulmonary embolism
• Prevention: Early mobilization, TEDS on,
Anticoagulation.

10. ‘Wonder drugs’
• Antimicrobials and heparin : one-third of
drug-related fever.
• Malignant hyperthermia: In genetically
susceptible induviduals to volatile anasthetics
• Discontinue the offending agent

11. ‘Withdrawal’
• Alcohol withdrawal
• Acute treatment is with high-dose
benzodiazepine: Diazepam or lorazepam

12. ‘Wonky glands’
• Addisonian crisis:
– Hypotension, hyponatremia, hyperkalemia,
hypoglycemia, unexplained fever
– Rx: Bolus of dexamethasone 4mg iv or
hydrocortisone 100mg iv
• Thyrotoxicosis
– Tachycardia, altered mental status,
hyper/hypotension, hyperthermia.
– Propranolol 1mg IV bolus, Propylthiouracil 200mg
oral

13. Reference
• Evaluating postoperative fever Kristopher R. Maday, MS, PA-C; John B.
Hurt, MS, PA-C; Paul Harrelson, MSPAS, PA-C; John Porterfield, MD
Copyright © 2016 American Academy of Physician Assistants