Surgical Site Infection Flashcards
Most common pathogens that cause SSI?
Gram pos - staph aureus
Coliforms:
Gram neg - e.coli
Proteus mirabilis
Definition of SSI?
An infection of the i) superficial or deep skin incision or of ii) an organ or iii) space, occurring up to 30 days post surgery ( if no implant left behind) or within 1 year of an implant was left in situ.
Diagnosis of SSI?
Only 1 of the following required:
i) Superficial wound infection
- pain, redness, tenderness, localised swelling or heat
- purulent effluent or exudate with organisms identified
- diagnosis of a superficial wound infection by a surgeon/attending physician
ii) Deep wound infection
- purulent erudite from a dep wound excision
- spontaneous dehiscence of a deep incisional wound OR a wound deliberately opened in the presence of pyrexia >38°C, localised pain or tenderness.
- evidence of abscess or infection (involving deep wound incisions found on direct examination of the wound, during reoperation, radiologically or histology.
- diagnosis of a deep incisional wound infection by absurgeon/attending physician
iii) Infection of an organ/space
- putulent exudate from a drain placed inside an organ or space
- organism isolated from the organ or space
- evidence of an abscess or infection (on direct examination of the wound)
- diagnosis of an organ or space wound infection by a surgeon/attending
Incidence of SSI?
2-6% in high income countries
Risk factors for SSI? [Patient factors]
Age
Chronic illness: DM, obesity, immunosuppression (alcohol, steroid suppression), anaemia
Social History: rural residence, smoking, poor nutritional status, length of preopstay
Imtrapartum & postpartum risk factors for SSI?
Intrapartum factors (12):
Frequent vaginal exams
Prolonged ROM
Pronged labour
Chorioamnionitis
Emergency LSCS
Prolonged sx
Poor surgical technique
Surgical drains
Not using antimicrobial antibiotics
PPH
Intrapartum pyrexia
P(PREMature)ROM
Postpartum factors (3):
-haematoma
-transfusion
-prolonged hospital stay
Organisms that cause Gynaecological SSIs?
E.coli/ gram neg bacilli
Enterococci
Group B haemolytic strep
Anaerobes
Recommendations to decrease risk of infection perioperatively?
- Reduce patient risk factors
- optimize chronic illnesses, e.g. adequate glycaemic control, good nutrition, optimise Hb status, avoid immunosuppression, stop smoking and weight optimization - Hair removal does not reduce risk, however of necessary use clippers as razors increase risk of SSI.
- Staph/MRSA nasal decolonisation in carriers (with an antiseptic) considered good practice
- Preoperative shower the day before or the day of surgery with soap - considered good practice as it decreases skin flora and colonization at the op site.
- Antibiotic prophylaxis:
Give within 60mins of skin incision
— decreases risk of SSI, endometritis and serious maternal infectious complication
–decreases complications by60-70%
— consider increased dose for morbidly obese women
– not recommended for clean, non-prosthetic, uncomplicated surgeries. - Skin prep decreases resident microflora and contamination of the surgical Site.
— Cochrane reviews show that Chlorhexidine in alcohol is superior to povidone iodine.
— a 30% decrease in SSI compared to pov-iodine.
– if alcohol based chlorhexidine is contraindicated, alcohol based pov-iodine is second line.
- allow the alcohol to dry for 3 mins
- allow chlorhex to dry 30s on abdomen - Shorter length of surgery
- consider readministering antibiotics if sx lasts >3hrs and EBL >1.5L
T/F. Prophylactic antibiotics are recommended for diagnostic laparoscopy, ovarian cystectomy and laparoscopic sterilization.
False. Prophylactic antibiotics are not recommended for clean, non-prosthetic, uncomplicated surgeries (such as those listed above)
What are the ideal prophylactic antibiotics for csections/hyste?
-Cefazolin 2g iv
OR
-Cefuroxime 1.5g + metro 500mg
*Co-amoxiclav 1.2g can be given for hyste (vag/abd) as an alternative
Penicllin Allergies?
Clindamycin 400mg iv + genta 5mg/kg
What is the prophylactic antibiotic for perineal sx?
Cefuroxime 1.5g iv + metro 500mg
Or
Co-amoxiclav 1.2g iv then oral 625mg tds x5/7
*Penicillin allergy?
- genta 5mg/kg + metro 500mg iv followed by oral Clindamycin 300-460mg po qid x 5/7
What is the prophylactic antibiotic for MRSA positive pts doing sx?
Teicoplanin 400mg iv + genta 5mg/kg
Does incidentally discovered bacterial vaginosis require treatment prior to surgery?
Yes, to minimise the risk of SSI.
Treat for 5-7 days prior to surgery, however BV is not a contraindication to sx and TX can be continued postop.
How many days postop do SSIs develop?
Day 4-7
Signs of endometritis?
Abd pain
Heavy lochia
Abnormal/purulent vaginal discharge
