Renal injury during hip fracture surgery: an exploratory study

Abstract

Background: The present observational study was undertaken to identify potential markers of poor outcome, such as renal failure and mortality, after hip fracture surgery. Methods: Forty-three patients, with a mean age of 78 years, were studied having undergone acute hip fracture surgery. Analysis included the urinary excretion of cortisol, albumin and sodium. The degree of fluid retention was evaluated based on the urinary excretion of metabolic end products. Fluid retention and the excretion of albumin and neutrophil gelatinase-associated lipocalin (NGAL) were measured repeatedly in a sub-group of 15 patients who also underwent haemodynamic monitoring. The perioperative change in serum creatinine and a 30-day mortality served as outcome measures. Results: Although serum creatinine increased by > 25% in 21% of the patients, only a high preoperative creatinine concentration correlated with a 30-day mortality. The subgroup analysis revealed that fluid retention was pronounced and remained essentially unchanged up to the first postoperative day. A rise in serum creatinine was always preceded by increased urinary excretion of NGAL that, in turn, was associated with preoperative fluid retention. The only perioperative event that correlated with a higher 30-day mortality was perioperative aggravation of albuminuria (67% vs 0%, P < 0.01), which became more common with advanced age and a low cardiac index. Conclusions: Two different mechanisms seem to affect the kidneys during hip fracture surgery. The first elevates the serum creatinine concentration while the second increases the albuminuria. Only the second mechanism had a bearing on mortality.

Volume kinetic analysis of fluid retention after induction of general anesthesia

“…3c). The theoretical importance of this process of is that patients with a low habitual intake of water might have their urine so much more concentrated during the surgery that the concentrating capacity of the kidneys is exceeded, which causes a postoperative rise in plasma creatinine [27][28][29]. Unfortunately, plasma creatinine was not measured after the surgery.…”

Renal water conservation determines the increase in body weight after surgery: A randomized, controlled trial

“…[19] In hip fracture surgery, a high preoperative FRI has been associated with a greater rise in NGAL[7] and a greater number of postoperative complications. [20] In acute geriatric care, an admission FRI of ≥4.0 was associated with a higher 30-day mortality.…”

“…[5678] To create this index, urine color was assessed immediately by holding a 10 ml tube of urine next to a color scale, which is available at www.hydrationcheck.com. The urine-specific gravity was measured by Multistix ® reagent strips inserted into a Clinitek Status ® Analyzer (Siemens Healthcare Diagnostics).…”

“…Consideration was given to the stress and inflammatory responses to the surgery and how strongly the kidneys excrete the retain fluid, which was analyzed in sampled urine. [5678] The hypothesis was that the increase in body weight correlates with the use of crystalloid fluid, high cortisol excretion, inflammation, and/or renal fluid retention.…”

Fluid Retention is Alleviated by Crystalloid but Not by Colloid Fluid after Induction of General Anesthesia: An Open-Labeled Clinical Trial

“…The kinetics of crystalloid fluid is fundamentally different when given to the preoperative patient with high urinary concentrations of waste products compared to another patient who has low concentrations. For example, renal fluid conservation prolongs the half-life [5] and greatly increases the plasma volume response [6] to crystalloids, and the urinary concentration of neutrophil gelatinase-associated lipocalin (NGAL) is more likely to increase [15]. An impact on postoperative health needs to be further elucidated, although fluid retention has already been shown to have a negative impact on outcome in elderly patients subjected to hip fracture repair surgery [1] and acute disease [7].…”