Abstract
Introduction
Acute kidney injury is a recognised post-operative complication in primary joint replacement. Recently it has been demonstrated that antibiotic regimen can significantly impact on the proportion of patients who develop acute kidney impairment post-operatively. Within our unit an increased rate of acute kidney injury had been noted post-operatively over the last 5 years. This increase followed the introduction of a rapid recovery protocol for arthroplasty patients. Our aim was determine whether we could identify a causative factor or those who were at increased risk of post-operative renal impairment.
Methods
Data were collected for 413 patients initially retrospectively but continued prospectively. Univariable and multivariable analysis was performed to determine any causative factors. The primary increase was 150% increase in baseline creatinine, but as some authors recognise an increase in 125% this was also analysed.
Results
Within the 12 month period studied 23.3% of patients developed acute kidney injury, with an increase of 125% of their baseline creatinine. 8.23% of patients developed an increase of 150% in their creatinine levels.
Age, previous renal failure and the pre-operative use of an ACE inhibitor were found to be statistically higher in the renal failure group. The uni-variable analysis also demonstrated that patients who received a small volume of post-operative intravenous fluids had a lower rate of renal failure than those who received no fluids (10% vs. 23%; p = 0.04).
The multivariable regression analysis demonstrated that age was the only statistically significant positive predictive factor in developing renal failure. Antibiotic regimen had no effect.
Discussion
Renal impairment has significant impact on patient morbidity and post-operative management. It increases the length of stay, and may potentially require more invasive therapy. We have demonstrated that the identified risk factors are non-modifiable but that a gentamicin and teicoplanin regimen was not an implicated causative factor.
