M.Rao St Richard’s Hospital, Chichester West Sussex. Does decolonisation of MRSA decrease the risk Of Surgical Site Infection in THA & TKA ? M.Rao St Richard’s Hospital, Chichester West Sussex.

Introduction Risk of developing SSI in trauma patients colonised with MRSA is 2.5 times greater than that of non-colonised patients. Shukla et al; J Bone Joint Surg Br -2009 Few studies to assess for incidence of SSI in MRSA carriers in elective orthopaedic surgery following decolonisation. Hacek et al- Clin Orthop Relat Res-2008. Rao et al-Clin Orthop Rel Research-2008. Decolonisation not confirmed prior to surgical intervention

Objectives Study to determine the risk of SSI in elective primary hip and knee replacements who had successful preoperative decolonisation and confirmed eradication of MRSA carrier status.

Patients and Methods Retrospective analysis of consecutive elective THA’S & TKA’s done between January 2008 and October 2012. List of patients generated using OPCS codes (Audit Dept.) for Primary THA & Primary TKR (cemented/uncemented/Hybrid). Microbiology data (sema helix). Infection Control data from Infection control Nurse specialists. (HES data)

MRSA decolonisation Protocol Standardised decolonisation protocol for MRSA+ve patients Mupirocin (2%) nasal ointment 3 times a day for 5 days. Daily bathing with chlorhexidine 4% / Surgical scrub for 5 days. Chlorhexidine 4% surgical shampoo for hair on days 1 & 3. Repeat full MRSA screens (3 sets of – ve swabs before surgery) Negative swabs ranged from 3-5 prior to surgery All patients in the study group had negative swabs (most within 3 weeks prior to surgery)

Detailed medical records of MRSA colonised patients assessed. Methods Detailed medical records of MRSA colonised patients assessed. Site of colonisation. Risk factors for colonisation. Co-morbidities. Eradication of colonisation status prior to surgery. Prophylactic antibiotics used in the peri-operative period.

(WHO guidelines for safe surgery-2009) Methods Development of SSI in the subsequent year after surgery MRSA negative patients cohort served as the control group. Only patients identified to have “ deep SSI” as defined by WHO classification were included in the study. (WHO guidelines for safe surgery-2009)

Results Over all Colonisation rate -1.3% Total No of Patients – 6613 MRSA positive - 83 Mean Age (MRSA positive) - 76 yrs M:F ratio 1:1.2 Sites of Colonisation Nasal-31 Multiple sites – 52 Patients Over all Colonisation rate -1.3%

Additional Risk Factors & Medical Co-Morbidities 3 patients were in the “high risk” category for MRSA colonisation. Previously colonised with MRSA - History of leg cellulitis and ulcers. Medical Co-morbidities Diabetes-15 patients Rheumatoid Arthritis(on steroids/methotrexate)- 7 patients. Stage 3 CKD-1 patient – Immunocompamised.

Perioperative Antibiotic prophylaxis 60% patients received Teicoplanin for antibiotic prophylaxis.

Results January 2008- October 2012 3347 THR’s 3266 TKR’s 6613 screened 79 positive 4 excluded 3347 THR’s 3266 TKR’s 6613 screened 83 MRSA + ve 5 deep SSI 6530 MRSA - ve

Results – MRSA Positive Patients Age Gender Procedure Site of colonisation Prophylactic Antibiotic Infection type 79 F TKR Multiple Flucl/Gent MRSA 80 M Teicoplanin MSSA 78 THR 84 5 of 79 patients had deep SSI 4 deep MRSA and 1 deep MSSA. 3 out of 5 patients who developed SSI had Teicoplanin. Overall infection rate of 6.32%

Analysis of Total Hip Replacements Previous MRSA colonisation Total THRs Deep sepsis THR Infection (%) Chi square value P- value Positive 38 2 5.26% 4.858 .0275 Negative 3307 39 1.17% .

Analysis of Total Knee Replacements Previous MRSA colonisation Total TKR Deep sepsis TKR Infection (%) Chi square value P- value Positive 41 3 7.31% 9.904 .0016 Negative 3223 42 1.3%

Literature In Elective Orthopaedic Surgery Rao N et al.- CORR -2008 Kim D et al.- JBJS (Am.)- 2010 ‘’ Identified implementation of universal screening & selective decolonisation of MRSA carriers leads to a reduction in post op SSI ’’. (These studies did not confirm eradication prior to surgery) Murphy et al.(Glasgow Royal Infirmary)-JBJS(Br.)-2011 Identified a 6.7% risk of SSI in elective orthopaedic surgery following confirmed decolonisation/eradication [ 1st study of this nature in literature] Cefuroxime was used as perioperative antibiotic prophylaxis (Queried if use of vancomycin/teicoplanin would make a difference)

Do we completely eradicate MRSA using current decolonisation protocols ???? Probably Not ! Valde’s C et al; Incidence of bacteraemia associated with tracheal intubation.- Anaesthesia-2008 Possible explanation- High rates of SSI in these patients is caused by bacteraemia ⟹ trauma to mucosa of URT during intubation ⟹ seeding of prosthetic implants ⟹ these areas not decolonised without use of oral chlorhexidine sprays.

Conclusions There is a significantly increased risk of SSI in MRSA colonised patients (6.32%) undergoing elective hip and knee replacements, despite confirmed eradication/decolonisation. Also, should infection develop, MRSA is the more often the causative organism. Patients should be made aware of this higher risk of infection and the serious consequences of developing MRSA SSI.

Conclusion Best way to treat MRSA is to avoid it! there's no app for MRSA eradication Thank You