We reviewed renal function of 22 patients who had undergone total knee replacements using the enhanced recovery protocol (Caledonian technique) between August 2012 and November 2012 at a district general hospital in the west of Scotland. Pre-operative and post operative data were compared to determine if there was any change. We observed that 4 out of 22 (18%) of patients had a significant rise in creatinine, and 6 out of 22 (27%) had an abnormal eGFR. These findings were significant and were classed as (Acute Kidney Injury) AKI type 1, which should be treated actively.

Subsequently, we collected data in the same way for 22 patients who underwent total knee replacements without using the enhanced recovery protocol. In this group, only one (5%) had a significant rise in creatinine and 2 (9%) had an abnormal eGFR.

Significant difference is noted in the two groups.

We conclude that the enhanced recovery protocol has some adverse effect on a patient's renal function. Our hypothesis is that this is due to restriction of fluids after surgery but a larger study is needed to find the cause and ways to avoid this.