Postoperative Fever

Question 1

What pathological processes might you consider in a pt developing a mild fever immediately post-op?

Answer 1

Usually benign:
Transfusion reaction
Medication reaction
Infection prior to surgery
Trauma

Question 2

What pathological processes might you consider in a pt developing a high fever immediately post-op?

Answer 2

Malignant hyperthermia (very rare)

Question 3

What pathological processes might you consider in a pt developing a fever acutely (in the first week)?

Answer 3

Surgical site infection
IV site infection with bacteraemia
UTI
HAP/aspiration pneumonia

Question 4

What pathological processes might you consider in a pt developing a fever sub-acutely (after the first week)?

Answer 4

Surgical site infection
IV site infection with bacteraemia
DVT
Drug reactions (e.g. Abx, phenytoin)
Other nosocomial infections (esp if in ICU)

Question 5

What pathological processes might you consider in a pt developing a fever in the delayed period (after a month)?

Answer 5

Surgical site infection

Viruses and transfusion (e.g. CMV)

Question 6

What details are important to elicit when taking a history from a pt with a post-op fever?

Answer 6

Symptoms of fever (e.g. sweats, rigors)
Pain (duration, exacerbation with movement or restriction, analgesic requirements)
Respiratory symptoms for pneumonia, PE (SOB, cough, sputum production, pleuritic chest pain)
UTI symptoms (urinary catheter-in-situ, dysuria, frequecy)
Pain in calves (DVT)
Peripheral IV sites

Question 7

What are the localising signs for central line-associated bloodstream infections?

Answer 7

Usually none

Question 8

If bacteruria is detected, what treatment should be commenced?

Answer 8

Generally not required unless symptomatic

Question 9

Risk factors for surgical wound infection

Answer 9

Host factors
Surgical factors
Prophylaxis (Abx choice, timing)

Question 10

List 8 host factors contributing to increased risk of surgical site infection

Answer 10

Age
DM
Obesity
Steroids
Smoking
Malnutrition
Infection at another site
Skin carriage of Staph aureus

Question 11

List 8 surgical factors contributing to increased risk of surgical site infection

Answer 11

Surgical technique (skill of operating with causing minimal tissue damage)
Type of surgery
Wound class
Operation duration
Hair removal
Skin prep used
Hypothermia
Theatre traffic

Question 12

What % of Staph aureus infections are MRSA? Are these mostly hospital or community strains?

Answer 12

15-20%

Hospital strains on the decline, community strains increasing

Question 13

When does HAP occur?

Answer 13

> 48 hours post-admission (increased risk in ventilated pts)

Question 14

When does VAP occur?

Answer 14

> 48 hours post-intubation

Question 15

What are the most common organisms responsible for HAP?

Answer 15

E. coli
Klebsiella
Enterobacter
Pseudomonas
Staph aureus (including MRSA)

Question 16

When are most resistant organisms likely to be causing the pneumonia and why?

Answer 16

In VAP, ICU pts due to longer hospital stay, previous Abx, immunosuppression, poor mobilisation

Question 17

What is the Abx of choice for HAP?

Answer 17

Requires knowledge of likely bacteria in particular hospital or ICU in recent months, including resistance patterns
In this hospital: ceftriaxone on wards, piperacillin/tazobactan +/- azithromycin for VAP

Question 18

Increased risk of HAP with PPI and H2 blockers

Answer 18

Growth of bacteria (not killed by the acid)

Suppression of coughing to clear lungs and pharynx