Intraoperative oliguria does not predict postoperative acute kidney injury in major abdominal surgery: a cohort analysis

Abstract

Background: Acute kidney injury (AKI) is a common complication in patients undergoing major abdominal surgery and is associated with considerable morbidity and mortality. Several studies investigating the association between intraoperative urine output and postoperative AKI have shown conflicting results. Here, we investigated the association of intraoperative oliguria with postoperative AKI in a cohort of patients submitted to elective major abdominal surgery. Methods: This was a single-center retrospective analysis of adult patients who underwent elective major abdominal surgery from January 2016 to December 2018. AKI was defined according to the serum creatinine criteria of the KDIGO classification. Intraoperative oliguria was defined as urine output of less than 0.5 mL/kg/h. Risk factors were evaluated using multivariate logistic regression analysis. Results: A total of 165 patients were analyzed. In the first 48 h after surgery the incidence of AKI was 19.4%. Postoperative AKI was associated with hospital mortality (p=0.011). Twenty percent of patients developed intraoperative oliguria. There was no association between preexisting comorbidities and development of intraoperative oliguria. There was no correlation between the type of anesthesia used and occurrence of intraoperative oliguria, but longer anesthesia time was associated with intraoperative oliguria (p=0.007). Higher baseline SCr (p=0.001), need of vasoactive drugs (p=0.007), and NSAIDs use (p=0.022) were associated with development of intraoperative oliguria. Intraoperative oliguria was not associated with development of postoperative AKI (p=0.772), prolonged hospital stays (p=0.176) or in-hospital mortality (p=0.820). Conclusion: In this cohort of patients we demonstrated that intraoperative oliguria does not predict postoperative AKI in major abdominal surgery.

Preoperative Concentrated Urine Increases the Incidence of Plasma Creatinine Elevation After Major Surgery

“…The background is probably multifactorial. Factors that are statistically associated with increasing plasma creatinine include arterial hypotension (4)(5)(6), restrictive fluid therapy (3,7) and a high body mass index (8), while opinions differ regarding the role of intraoperative oliguria (9,10).…”

Incidence and Associations of Acute Kidney Injury after General Thoracic Surgery: A System Review and Meta-Analysis

“…The perioperative period is when special pathophysiological conditions challenge the diagnosis of AKI, such as muscle injury, volume overload or hypovolemia, and the release of aldosterone and vasopressin from stress [45,46], which may well have an impact on the measurements of creatinine levels and oliguria [35,36,47,48]. Doctors and researchers have striven to find a "troponin-equivalent" marker for the precise identification of patients with AKI at an early stage, such as cystatin C, kidney injury molecule-1, or neutrophil gelatinaseassociated lipocalin [49][50][51].…”

Urine biochemistry assessment in the sequential evaluation of renal function: Time to think outside the box

“…Therefore, a low CrU does not imply reduced creatinine excretion in patients with high UO. Conversely, prolonged oliguria is common in postoperative patients and not always followed by increases in sCr ( 27 , 28 ). This is explained by a preserved mass of creatinine excreted per unit of time which means a great ability to concentrate creatinine in a lower urine volume.…”