Minor Postoperative Increases of Creatinine Are Associated with Higher Mortality and Longer Hospital Length of Stay in Surgical Patients

Abstract

Background Surgical patients frequently experience postoperative increases in creatinine levels. The authors hypothesized that even small increases in postoperative creatinine levels are associated with adverse outcomes. Methods The authors examined the association of postoperative changes from preoperative baseline creatinine with all-cause in-hospital mortality and hospital length of stay (HLOS) in a retrospective analysis of surgical patients at a single tertiary care center between January 2006 and June 2012. Results The data of 39,369 surgical patients (noncardiac surgery n = 37,345; cardiac surgery n = 2,024) were analyzed. Acute kidney injury (AKI)—by definition of the Kidney Disease: Improving Global Outcome group—was associated with a five-fold higher mortality (odds ratio [OR], 4.8; 95% CI, 4.1 to 5.7; P < 0.001) and a longer HLOS of 5 days (P < 0.001) after adjusting for age, sex, comorbidities, congestive heart failure, preoperative hemoglobin, preoperative creatinine, exposure to radiocontrast agent, type of surgery, and surgical AKI risk factors. Importantly, even minor creatinine increases (Δcreatinine 25 to 49% above baseline but < 0.3 mg/dl) not meeting AKI criteria were associated with a two-fold increased risk of death (OR, 1.7; 95% CI, 1.3 to 2.4; P < 0.001) and 2 days longer HLOS (P < 0.001). This was more pronounced in noncardiac surgery patients. Patients with minor creatinine increases had a five-fold risk of death (OR, 5.4; 95% CI, 1.5 to 20.3; P < 0.05) and a 3-day longer HLOS (P < 0.01) when undergoing noncardiac surgery. Conclusions Even minor postoperative increases in creatinine levels are associated with adverse outcomes. These results emphasize the importance to find effective therapeutic approaches to prevent or treat even mild forms of postoperative kidney dysfunction to improve surgical outcomes.

Acute kidney injury and mortality 1 year after major non-cardiac surgery

“…Postoperative AKI was defined according to the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 creatinine criteria 17 , namely a 1⋅5-fold increase in serum creatinine level from preoperative baseline or an absolute 26-μmol/l increase over a period of 48 h or less within the 7 days after surgery. Additionally, separate analyses were performed to examine postoperative outcomes in patients defined as having AKI stage 1 based purely on a 26-μmol/l increase without a rise in serum creatinine from baseline of at least 50 per cent; and in patients who experienced an increase in serum creatinine of 25 per cent or more from baseline, but less than 50 per cent, within 7 days after surgery, and did not otherwise achieve the KDIGO AKI definition by an absolute 26-μmol/l increase within 48 h. The latter group has been associated with adverse outcomes in previous studies 6 . Baseline serum creatinine was taken as the most recent value available between 7 and 365 days before the day of surgery 18 ; if none was available, the value closest to 7 days before surgery was used.…”

Pre-Stage Acute Kidney Injury Can Predict Mortality and Medical Costs in Hospitalized Patients

“…Recently, Liotta et al showed that small increases in serum creatinine (0–0.3 mg/dl) were significantly associated with long-term mortality, but not with short-term (1 month) mortality, in patients following cardiac surgery [24]. Kork et al revealed that minimal increases in serum creatinine (25–50% increase from baseline, value less than 0.3 mg/dl) resulted in increased in-hospital mortality and length of hospital stay in post-surgical patients [25]. Although these studies investigated the effect of small increases in serum creatinine on clinical outcomes, they are limited to specific patient populations, i.e., patients who underwent cardiac surgery or heart failure patients.…”

Acute kidney injury after open and endovascular elective repair for infrarenal abdominal aortic aneurysms

“…Postoperative AKI is generally a risk factor for mortality after different kinds of surgery. 15,16 Regarding abdominal aortic surgery, Wald et al 13 already highlighted the higher risk of mortality (after both EVAR and OAR) in the presence of AKI (OR, 11.3%). Nevertheless, we could not include early mortality in the multivariate analysis because of the small number of cases in both groups.…”