Pyrexia

Question 1

What is pyrexia?

Answer 1

Pyrexia (fever) refers to a raised body temperature, typically greater than 37.5°C.

Question 2

Is pyrexia common in surgical patients?

Answer 2

Yes, it can be a normal immediate post-operative response or a feature of a specific post-operative complication.

Question 3

What are the typical causes of pyrexia on post-operative days 1-2?

Answer 3

1. Respiratory source.
2. Body’s routine response to surgery.

Question 4

What are the typical causes of pyrexia on post-operative days 3-5?

Answer 4

1. Respiratory infection.
2. Urinary tract infection.

Question 5

What are the typical causes of pyrexia on post-operative days 5-7?

Answer 5

1. Surgical site infection.
2. Abscess or collection formation.

Question 6

What should be considered if pyrexia occurs on any post-operative day?

Answer 6

Infected intravenous (IV) lines or central lines.

Question 7

What is an important differential diagnosis for pyrexia in a patient with a bowel resection and anastomosis?

Answer 7

Anastomotic leak.

Question 8

Name three non-infectious causes of post-operative pyrexia.

Answer 8

1. Iatrogenic (e.g., drug-induced reaction or transfusion reaction).
2. Venous thromboembolism (e.g., PE or DVT).
3. Secondary to prosthetic implantation.

Question 9

What is Pyrexia of Unknown Origin (PUO)?

Answer 9

Recurrent fever (>38°C) persisting for >3 weeks without an obvious cause, despite >1 week of inpatient investigation.

Question 10

What are the common causes of PUO?

Answer 10

1. Infection of unknown source (30%).
2. Malignancy (e.g., lymphoma with B-symptoms, 30%).
3. Connective tissue diseases or vasculitis (30%).
4. Drug reactions.

Question 11

What should be the initial approach for a surgical patient presenting with pyrexia and appearing unwell?

Answer 11

Start with an A to E approach for resuscitation and stabilization.

Question 12

What symptoms should be specifically enquired about in a patient with post-operative pyrexia?

Answer 12

1. Urinary frequency, urgency, or dysuria.
2. Productive cough or dyspnoea.
3. Haemoptysis.
4. Chest or calf pain.
5. Wound or cannula line tenderness.

Question 13

What signs should you look for during the examination of a surgical patient with pyrexia?

Answer 13

1. Respiratory infection signs.
2. IV line infections.
3. Wound infections.
4. Calf tenderness.
5. Signs of specific post-operative complications (e.g., peritonism in an anastomotic leak).

Question 14

What is included in a septic screen for post-operative pyrexia?

Answer 14

1. Blood tests (FBC, CRP, U&E, LFTs, clotting).
2. Urine dipstick ± urine MCS.
3. Cultures (blood, urine, sputum, wound swab).
4. Imaging (plain film chest radiograph, cross-sectional imaging).

Question 15

What should be done if no infection source is identified through a septic screen?

Answer 15

Consider more detailed investigations and consult a senior or microbiologist.

Question 16

How should identified infections be treated in post-operative pyrexia?

Answer 16

Treat with empirical antibiotics based on local guidelines, pending sensitivity results from cultures.

Question 17

Should empirical antibiotics be started immediately if no infectious cause is identified?

Answer 17

Not always. First consider non-infectious causes and consult a senior colleague or microbiologist.

Question 18

What should you do if there is any suspicion of sepsis in a surgical patient with pyrexia?

Answer 18

Have a low threshold for suspicion and involve a senior colleague for early review.

Question 19

What are the key considerations when managing pyrexia in a surgical patient?

Answer 19

1. Use an A to E approach for all cases.
2. Consider the time since operation and procedure details to focus investigations.
3. Remember that not all cases of pyrexia are due to infection.