title: The Doppler renal resistive index for early detection of acute kidney injury after hip fracture.
abstract: BACKGROUND
  Postoperative acute kidney injury (AKI) is linked to an increase in morbidity and mortality, particularly in elderly populations. This study's aim was to assess the accuracy of the Doppler renal resistive index (RI) in detecting AKI at an early stage after hip fracture surgery.
  
  
  METHODS
  This prospective single-centre study included 48 patients suffering hip fractures requiring surgery and who presented risk factors for the development of AKI. The RI was calculated preoperatively and postoperatively in patients without pain and with haemodynamic and respiratory stability. The occurrence of AKI was determined by measurements of serum creatinine according to AKIN criteria.
  
  
  RESULTS
  Twenty-nine patients (60%) developed AKI during the first five postoperative days, without need for dialysis. The RI was increased in patients who developed postoperative AKI 0.68 (0.67-0.71) vs. 0.72 (0.7-0.73); P=0.014 for the preoperative index; and 0.6 (0.58-0.68) vs. 0.74 (0.71-0.76); P<0.0001 for the postoperative index. A postoperative index superior or equal to 0.706 is a marker for the early detection of AKI with a high sensitivity and a high specificity (76% and 89%, respectively).
  
  
  CONCLUSIONS
  The calculation of the RI during the perioperative periods of hip fracture surgery predicts early and effectively the postoperative occurrence of AKI, thus allowing treatment to be anticipated so as to improve patient prognosis.
authors.affiliation: Department of Anesthesiology and Intensive Care, Rangueil University Hospital, avenue Jean-Poulhès, 31059 Toulouse, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Marty
authors.affiliation: Department of Anesthesiology and Intensive Care, Rangueil University Hospital, avenue Jean-Poulhès, 31059 Toulouse, France.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Ferre
authors.affiliation: Department of Anesthesiology and Intensive Care, Rangueil University Hospital, avenue Jean-Poulhès, 31059 Toulouse, France.
authors.forename: François
authors.initials: F
authors.lastname: Labaste
authors.affiliation: Department of Anesthesiology and Intensive Care, Rangueil University Hospital, avenue Jean-Poulhès, 31059 Toulouse, France.
authors.forename: Loriane
authors.initials: L
authors.lastname: Jacques
authors.affiliation: Department of Anesthesiology and Intensive Care, Rangueil University Hospital, avenue Jean-Poulhès, 31059 Toulouse, France.
authors.forename: Aymeric
authors.initials: A
authors.lastname: Luzi
authors.affiliation: Department of Anesthesiology and Intensive Care, Rangueil University Hospital, avenue Jean-Poulhès, 31059 Toulouse, France.
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Conil
authors.affiliation: Department of Anesthesiology and Intensive Care, Rangueil University Hospital, avenue Jean-Poulhès, 31059 Toulouse, France.
authors.forename: Stein
authors.initials: S
authors.lastname: Silva
authors.affiliation: Department of Anesthesiology and Intensive Care, Rangueil University Hospital, avenue Jean-Poulhès, 31059 Toulouse, France. Electronic address: minville.v@chu-toulouse.fr.
authors.forename: Vincent
authors.initials: V
authors.lastname: Minville
mesh_terms: D058186:Acute Kidney Injury / Q000000981:diagnostic imaging* / Q000209:etiology* / Q000628:therapy; D000368:Aged; D000369:Aged, 80 and over; D003404:Creatinine / Q000097:blood; D042241:Early Diagnosis; D005260:Female; D006439:Hemodynamics; D006620:Hip Fractures / Q000150:complications* / Q000601:surgery*; D017052:Hospital Mortality; D006801:Humans; D007677:Kidney Function Tests; D008297:Male; D011182:Postoperative Care; D011183:Postoperative Complications / Q000000981:diagnostic imaging* / Q000628:therapy; D011379:Prognosis; D011446:Prospective Studies; D018608:Ultrasonography, Doppler / Q000379:methods*
chemical_list: D003404:Creatinine
keywords: Acute kidney injury; Elderly; Hip fracture; Renal resistive index