A. E. Siletz1, J. Grotts2, C. E. Lewis1, A. Tillou1, H. Cryer1, A. Cheaito1 1University Of California – Los Angeles,Department Of Surgery, David Geffen School Of Medicine At UCLA,Los Angeles, CA, USA 2University Of California – Los Angeles,UCLA Department Of Medicine Statistics Core, David Geffen School Of Medicine At UCLA,Los Angeles, CA, USA
Introduction: AKI requiring renal replacement therapy (RRT) represents the most severe form of post-traumatic AKI, and has been associated with poor outcomes. Incidence and clinical impact vary by study due to variations in study population and definitions. The objective of this study was to determine the correlation between initiating dialysis and clinical outcomes in trauma patients using a national dataset.
Methods: All patients in the National Trauma Database from 2013-2014 with a diagnosis of AKI based on ICD9 code during admission for trauma were reviewed. Patients were excluded if they had no signs of life on arrival, were under age 18, or had pre-existing end-stage renal disease. A propensity score based on ISS, penetrating injury, age, and gender was used to match patients with AKI requiring dialysis with those with AKI who did not need dialysis. A multivariate logistic regression model using dialysis, ISS, injury type, age, and gender as covariates was also constructed.
Results: Among adult patients surviving to admission for trauma without pre-existing end-stage renal disease, the incidence of AKI was 1.07% and the incidence of AKI requiring dialysis was 0.02%. 17668 trauma patients with AKI, of which 282 received dialysis, were compared. Older age, male gender, black/African American race and Medicare and Medicaid coverage were significantly associated with dialysis (p<0.02). Penetrating injury was more likely to be associated with dialysis than blunt injury (OR 3, 95% CI 2.3-4, p<0.001) and dialysis patients had higher median ISS scores (26.5, IQR 18-35.2 vs. 17, IQR 9-29, p <0.001). When patients were matched using a propensity score based on ISS, penetrating injury, and age, dialysis patients were found to have higher complication rates including unplanned intubation (OR 3, 95% CI 1.6-5.6, p <0.001), unplanned return to the operating room (OR 7.3, 95% CI 3.8-14, p <0.001), acute lung injury/acute respiratory distress syndrome (OR 4.7, 95% CI 3-7.3, p <0.001), pulmonary embolism (OR 3.1, 95% CI 1.3-7.2, p =0.013), severe sepsis (OR 11.3, 95% CI 6.4-19.9, p <0.001), myocardial infarction (OR 4, 95% CI 1.5-10.7, p =0.009), and death (OR 3.8, 95% CI 2.7-5.2, p <0.001). Median hospital stay (27 vs. 8 days, p <0.001), ICU stay (19 v. 5 days, p < 0.001), and number of ventilator days (16 vs 5 days (p < 0.001) were significantly higher for dialysis patients. In a multivariate logistic regression model, initiating dialysis was significantly associated with development of acute respiratory distress syndrome (OR 4.8, 95% CI 3.1-7.6, p < 0.001), severe sepsis (OR 12.2, 95% CI 7.0-22.2, p < 0.001), and mortality (OR 4.0, 95% CI 2.9-5.6, p<0.001).
Conclusion:
AKI requiring dialysis after trauma is rare. Risk factors include high ISS and penetrating injury. The need for dialysis after AKI during admission for trauma is associated with increased complications, length of hospital stay, and mortality.