At our district general hospital in the southwest of England, around 694 total knee replacements (TKR) are performed annually. Since spring 2013 we have been using an enhanced recovery protocol for all TKR patients, yet we have neither assessed compliance with the protocol nor whether its implementation has made a discernible and measurable difference to the delivery of care in this patient population. Enhanced recovery after surgery (ERAS) protocols are multi-modal care pathways designed to aid recovery. They are based on best evidence and promote a multi-disciplinary approach which standardises care and encompasses nutrition, analgesia and early mobilisation throughout the pre, intra and postoperative phases of an inpatient stay. ERAS has been found to reduce length of stay (LOS), readmission rates and analgesic requirements following surgery.^{1, 2, 3} Additionally, they have been shown to improve range of knee movement following TKR and improve mobility, patient satisfaction whilst reducing mortality and morbidity.^{4, 5, 6} With these benefits in mind, we sought to investigate how well our trauma and orthopaedic department was complying with a local ERAS protocol and whether we could replicate the benefits seen within the literature.

Following approval from our local audit office in September 2015 we generated a patient list of elective TKR patients under the same surgeon before and after the implementation of the ERAS protocol. Using discharge summaries and patient notes we extracted data for 39 patients operated on prior to the ERAS implementation between January 2011 and December 2012 and 27 patients following its introduction between January 2014 and September 2015. Data collected included length of stay, time to discharge from inpatient physiotherapy and use of analgesia and antiemetics. Alongside this we audited the compliance with all facets of the local ERAS protocol.

There was no statistically significant difference between the 2 groups in terms of demographics or pre-operative morbidity. Overall compliance with the ERAS protocol was good but there was some variability, especially with intraoperative medication and type of anaesthesia which was likely due to individual patient factors. Compliance with postoperative analgesia was especially good with 93% of patients receiving all 4 suggested analgesics within the ERAS group. Length of stay (LOS) was significantly reduced by 0.5 days per patient (p value < 0.4).

Overall compliance with the ERAS protocol was good but there was some variability, especially with intraoperative medication and type of anaesthesia, which was likely due to individual patient factors. Compliance with postoperative analgesia was especially good with 93% of patients receiving all suggested analgesics within the ERAS group. In terms of LOS, we found a statistically significant difference between the pre-ERAS and ERAS group of 0.5 days per patient. Within the context of our DGH, a 0.5 day reduction in LOS translates to around 350 bed days per year and a potential saving of GBP 105,000 (EUR 132,000) making this a clinically significant finding.