STEMMING THE TIDE OF INFECTION. PRE-OPERATIVE ASSESSMENT, RINGFENCING AND THE CONTROL OF METHICILLIN RESISTANT STAPHLOCOCCUS AUREUS

Abstract

Background: MRSA is a major economic and health issue in Ireland and as such is of particular importance in the appropriate management of orthopaedic patients. Bone, joint and implant infection can lead to unfavourable outcomes with a long protracted in hospital stay inevitable. The cost for the patient, the hospital and society are substantial. Numerous protocols have been proposed internationally to aid in the management of MRSA infection in orthopaedic patients with pre assessment and ring fencing of patients shown to have a favourable impact.

Aims: To analyse the impact of a series of infection control measures on the infection and prevalance of MRSA in both elective and trauma orthopaedic patients.

Methods: We conducted a prospective study of our unit over three time points from 2005 to 2008. All elective and trauma orthopaedic surgery was based in Merlin Park Hospital up until December 2006. Since then all elective orthopaedic surgery has remained based in Merlin Park Hospital with all trauma surgery being moved to University Hospital Galway and all trauma patients based in an exclusively ring fenced orthopaedic ward. We recorded total rates of MRSA infection and colonisation in all orthopaedic patients over nine months of each year from 2005 to 2008, pre and post separation of trauma and elective services. Of note a pre admission screening protocol was implemented in March of 2006. We also prospectively recorded all MRSA data in patients treated through our ring fenced trauma ward from its opening date in November 2006.

Results: 12259 patients were reviewed between 2005 and 2008. The mean age of all admitted patients was 46 with th emean age of all MRSA positiv epatients being 71(p=0.000). There was no statistical difference for gender distribution between MRSA positive patients, but more women were positive than men.

The rates of MRSA infection for 2005, 2006 and 2007 were 0.49%, 0.28% and 0.24% respectively (binomial comparison, 2005 to 2006, p< 0.005 and 2005 to 2007, p< 0.005). Again when trauma and elective units were seperated there was a corrected rate of infection of 0.14% and 0.33% respectively. In 2005 there was 9 Superficial Incisional (SI), 8 Organ Space Infection(OSI) and 4 Deep Incisional (DI), 2006 had 7 SI, 4 OS and 4 DI and in 2007 there was 9 SI, 9 OS and 1 DI seen in the elective unit There was no Deep MRSA infection seen in the new ring fenced trauma unit. MRSA infection was found to cause a considerable increase in length of stay with normal orthopaedic patients staying a mean of 5 days whilst MRSA patients staying 23.4 days (p=0.000).

Conclusion: The separation of emergency and elective orthopaedic services coupled with effective preoperative screening has resulted in a reduction of MRSA infection and improved patient outcome.