Diclofenac does not decrease renal blood flow or glomerular filtration in elderly patients undergoing orthopedic surgery

Nonsteroidal antiinflammatory drugs (NSAIDs) have become increasingly popul ar in the treatment of perioperative pain. Due to concerns that cyclooxygen ase inhibition may adversely affect renal function, these drugs are often n ot used in geriatric surgical patients. However, the perioperative effect o f NSAIDs on renal blood flow (RBF) and glomerular filtration rate (GFR) has not been assessed. Therefore, using a prospective, controlled, double-blin ded study design, we evaluated the effect of diclofenac on RBF and GFR in 2 0 patients (>65 pr) undergoing open reduction and internal fixation of the femur. All patients were normovolemic before the study. A standardized gene ral anesthetic was administered. On induction of anesthesia, patients in th e diclofenac group received an TV bolus of diclofenac (0.7 mg/kg) followed by a constant infusion (0.15 mg.kg(-1).h(-1)) until the end of surgery. Ln the saline group, an equal volume of saline was administered. During four t ime periods (equilibration, anesthesia, surgical, recovery), GFR and effect ive renal plasma flow (ERPF) were measured by inulin and paraaminohippurate clearance, respectively. After the induction of anesthesia and throughout the surgical period, ERPF and GFR were significantly decreased compared wit h preoperative baseline values. However, no difference was demonstrated bet ween the groups. These results suggest that, in geriatric surgical patients , the adjuvant administration of NSAIDs does not adversely affect renal fun ction. Implications: As determined by inulin and paraaminohippurate clearan ce, the intraoperative administration of diclofenac does not decrease glome rular filtration rate or effective renal plasma flow in normovolemic geriat ric patients. Therefore, diclofenac map be administered during the perioper ative period.