surgical infection and antibiotics Flashcards
What are the risk factors for wound infection
General factors Age Malnutrition Immunosuppression Malignancy Obesity
Local factors Type of surgery (Clean vs contaminated) Length of procedure Tissue ischaemia Foreign body insertion Residual local malignancy
Microbiological factors
Lack of antibiotic prophylaxis
Virulence of the organism
what are the types of surgical site infection
Superficial and deep
superficial - infection of skin and subcutaneous tissue (most common)
deep - deep tissues (muscle/fascial layers), including organ space SSIs
what are the indications for preoperative antibiotics
contaminated or dirty operations
placement of foreign materials
patients with high risk of infection, OR high risk of severe complications of infection
immunosuppressed patients
previous foreign body implants
heart valve disease
peripheral vascular disease
although it depends on local guidelines, what is the most common combination of antibiotics used for preoperative antibiotics
cefuroxime and metronodazole
how is the timing of preoperative antibiotics important
the highest tissue concentration is required at the moment of tissues contamination so the infusion is usually started at the time of the first incicion
what causes aerobic gangrene
clostridium perfringens
what is the treatment for aerobic gangrene
aggressive debridement
IV penicillin
metronidazole
what causes synergistic gangrene
aerobes and synergystic anaerobes infecting a woun
what are the important post operative checks
Review general observations, urine output, mobility, faeces?
Inspect wound for superficial infection/haematoma
Inspect cannula site for thrombophlebitis /infection
Examine chest to exclude infection, infarction or acute heart failure
Examine the legs for DVT
Consider other sources of infection
where are common locations for post-operative abscesses to be
alongside the organ of origin
pelvic
subphrenic
what are common features of a post-op abscess
swinging fever malaise anorexia tachycardia palpable mass
how do you diagnose a post op abscess
CT abdo/pelvis
how do you manage a post op abscess
IV empirical Abx
Radiologically guided drainage when possible
Surgical drainage is last line measure
