Update on Perioperative Acute Kidney Injury

Alexander Zarbock, MD; Jay L. Koyner, MD; Eric A. J. Hoste, MD; John A. Kellum, MD

Disclosures

Anesth Analg. 2018;127(5):1236-1245. 

In This Article

Abstract and Introduction

Abstract

Acute kidney injury (AKI) in the perioperative period is a common complication and is associated with increased morbidity and mortality. A standard definition and staging system for AKI has been developed, incorporating a reduction of the urine output and/or an increase of serum creatinine. Novel biomarkers may detect kidney damage in the absence of a change in function and can also predict the development of AKI. Several specific considerations for AKI risk are important in surgical patients. The surgery, especially major and emergency procedures in critically ill patients, may cause AKI. In addition, certain comorbidities, such as chronic kidney disease and chronic heart failure, are important risk factors for AKI. Diuretics, contrast agents, and nephrotoxic drugs are commonly used in the perioperative period and may result in a significant amount of in-hospital AKI. Before and during surgery, anesthetists are supposed to optimize the patient, including preventing and treating a hypovolemia and correcting an anemia. Intraoperative episodes of hypotension have to be avoided because even short periods of hypotension are associated with an increased risk of AKI. During the intraoperative period, urine output might be reduced in the absence of kidney injury or the presence of kidney injury with or without fluid responsiveness. Therefore, fluids should be used carefully to avoid hypovolemia and hypervolemia. The Kidney Disease: Improving Global Outcomes guidelines suggest implementing preventive strategies in high-risk patients, which include optimization of hemodynamics, restoration of the circulating volume, institution of functional hemodynamic monitoring, and avoidance of nephrotoxic agents and hyperglycemia. Two recently published studies found that implementing this bundle in high-risk patients reduced the occurrence of AKI in the perioperative period. In addition, the application of remote ischemic preconditioning has been studied to potentially reduce the incidence of perioperative AKI. This review discusses the epidemiology and pathophysiology of surgery-associated AKI, highlights the importance of intraoperative oliguria, and emphasizes potential preventive strategies.

Introduction

Acute kidney injury (AKI) is an abrupt decline of the kidney function that occurs within a few hours or days. The term AKI appreciates that smaller declines in kidney function that do not result in overt organ failure are still of clinical relevance and are associated with increased morbidity and mortality.[1] AKI is a possible reversible syndrome that can develop in patients with and without comorbidities. Sepsis, major surgery, and various drugs are the leading causes of AKI.[1] Although AKI is a common complication in the perioperative period, it remains an underdiagnosed clinical condition. The consensus criteria that were developed recently have helped to attract more attention toward this serious clinical syndrome.[2] Based on the new definition, AKI is now being diagnosed more frequently over the last 2 decades. The new consensus definition is based exclusively on urine output and/or serum creatinine (SCr), thereby classifying different AKI severity stages (Table 1).[2] Since the advent of standard criteria for AKI culminating in the Kidney Disease: Improving Global Outcomes (KDIGO) criteria,[2] there has been an increased appreciation for AKI in terms of both its frequency and impact on survival. Furthermore, even mild changes in kidney function, as assessed by SCr, urine output, or both, seem to be associated with short- and long-term adverse outcomes. However, both functional markers have several limitations, including the inability to allow an early diagnosis. Thus, there is a need for an early identification of high-risk patients to immediately initiate preemptive treatment.

During the 2018 IARS meeting in Chicago, we had an Anesthesia & Analgesia-sponsored symposium dealing with the most important aspects of perioperative AKI, including epidemiology and pathophysiology of surgery-associated AKI (SA-AKI), importance of intraoperative oliguria, and potential preventive strategies. This review summarizes the talks and covers these aspects.

Comments

3090D553-9492-4563-8681-AD288FA52ACE

processing....