Inhaled nitric oxide prevents NSAID-induced renal impairment in pseudo-normovolaemic piglets

OBJECTIVE: Inhaled nitric oxide (iNO) is commonly used as a treatment of pulmonary hypertension. Its action is purported to be specific to the lung, but extrapulmonary effects have been reported. The objective of this study was to evaluate if iNO could compensate the renal impairment induced by ketoprofen, a conventional non-steroidal anti-inflammatory drug (NSAID), during general anaesthesia. METHODS: Under pseudo-normovolaemic condition, thirty piglets were randomly assigned into 5 equal groups and equipped for renal and systemic parameters measurements. A first experiment was carried out to validate methods and reproduce the renal effects of iNO (40 ppm) in comparison with a placebo (100% oxygen). In a second experiment, iNO was inhaled for 120 minutes right after NSAID treatment (ketoprofen 2 mg×kg(-1) IV, and 40 ppm iNO; group KiNO) and its effects were compared to ketoprofen alone (2 mg×kg(-1) IV; group K) and placebo (saline; group C). RESULTS: In this model, iNO increased significantly renal blood flow measured by ultrasonic (RBF(UL): +53.2±17.2%; p = 0.008) and by PAH clearance (RBF(PAH):+78.6±37.6%; p = 0.004) methods, glomerular filtration rate (GFR: +72.6±32.5%; p = 0.006) and urinary output (UO: +47.4±24.2%; p = 0.01). In the second experiment, no significant temporal variation was noted for renal parameters in groups KiNO and C, whereas a significant and constant decrease was observed in the group K for RBF(UL) (max -19.0±7.1%), GFR (max -26.6±10.4%) and UO (max -30.3±10.5%). CLINICAL SIGNIFICANCE: Our experiments show that iNO, released from its transport forms after its inhalation, can improve renal safety of NSAIDs. This result is promising regarding the use of NSAIDs in critical conditions, but needs to receive clinical confirmation.