Acute kidney injury post-major orthopaedic surgery: A single-Centre case-control study

Area of Science:

• Nephrology
• Orthopedic Surgery
• Pharmacology

Background:

• Acute kidney injury (AKI) is a significant complication following major surgical procedures.
• Identifying modifiable risk factors for AKI is crucial for patient outcomes in orthopedic surgery.
• Previous studies have suggested various factors contributing to AKI, but specific medication associations require further investigation in this surgical cohort.

Purpose of the Study:

• To determine the risk factors associated with the development of acute kidney injury (AKI) in patients undergoing major orthopedic surgery.
• To investigate the specific role of perioperative medications, including diuretics, non-steroidal anti-inflammatory drugs (NSAIDs), and renin-angiotensin system inhibitors, in AKI pathogenesis.
• To quantify the association between identified risk factors and the incidence of AKI post-orthopedic surgery.

Main Methods:

• A retrospective audit of patients undergoing major orthopedic surgery at University Hospital Geelong from 2008 to 2014.
• Identification of AKI cases using RIFLE criteria, with 2:1 matching to controls based on age, sex, procedure, and chronic kidney disease stage.
• Conditional logistic regression analysis to assess associations between perioperative medications (gentamicin, diuretics, NSAIDs, ACE inhibitors/ARBs), comorbidities (cardiovascular disease, liver disease, hypertension, diabetes), sepsis, and obesity with AKI.

Main Results:

• 164 cases of AKI were identified in an elderly cohort (median age 73 years).
• Perioperative use of diuretics (OR 2.06) and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (OR 2.09) were associated with a twofold increased risk of AKI.
• A linear relationship was observed between the frequency of non-steroidal anti-inflammatory drug administration and the risk of postoperative AKI (OR 1.35).

Conclusions:

• Perioperative diuretics, non-steroidal anti-inflammatory drugs, and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers are significantly associated with postoperative acute kidney injury in major orthopedic surgery.
• These medication classes represent key modifiable risk factors that warrant careful consideration in the perioperative management of orthopedic patients.
• Further prospective studies are recommended to validate these findings and explore potential interventions to mitigate AKI risk.