title: A targeted remifentanil administration protocol based on the analgesia nociception index during vascular surgery.
abstract: BACKGROUND
  The intraoperative modulation of opioids continues to be based on clinical signs. This may result in adverse events such as sympathetic reactivity or opioid-induced hyperalgesia. Recently, the Analgesia/Nociception Index (ANI), a non-invasive 0-100 index derived from heart rate variability analysis, has been proposed for nociception assessment. However, the ability of the ANI to adequately guide intraoperative opioid administration has never been demonstrated. We designed a prospective study to evaluate the ability of the ANI to guide remifentanil administration in vascular surgery.
  
  
  METHODS
  One hundred and eighty adults presenting for elective surgery were included. All received total intravenous anaesthesia with propofol adjusted to entropy and remifentanil adjusted to the ANI. The primary endpoint was the number of patients without any episode of reactivity defined as a 20% increase in heart rate or arterial pressure or the occurrence of movement. Secondary endpoints included opioid use and maximal pain rate in the first postoperative day.
  
  
  RESULTS
  Anaesthesia was achieved without any episode of reactivity in 160 (89%) patients. Twenty-five episodes of reactivity occurred in 20 (11%) patients. The median remifentanil dose was 0.042 [0.040-0.044]μg.kg-1.min-1. At 24hours, the maximal NRS pain score was 2 [2,3]. One hundred and fifty-five patients (86%) did not receive any postoperative opioids, whereas 25 (14%) received a median dose of 5[5-10] mg of oxycodone.
  
  
  CONCLUSIONS
  This prospective study demonstrated that the ANI can be used to adequately guide intraoperative remifentanil administration during vascular surgery. Such guidance resulted in low remifentanil consumption, low postoperative pain rates and low opioid rescue analgesia.
authors.affiliation: CHU de Caen, avenue de la Côte-de-Nacre, CS 30001, 14000 Caen, France; EA 4650, université de Caen Basse-Normandie, esplanade de la Paix, CS 14032, 14000 Caen, France. Electronic address: daccache-g@chu-caen.fr.
authors.forename: Georges
authors.initials: G
authors.lastname: Daccache
authors.affiliation: CHU de Caen, avenue de la Côte-de-Nacre, CS 30001, 14000 Caen, France.
authors.forename: Edouard
authors.initials: E
authors.lastname: Caspersen
authors.affiliation: CHU de Caen, avenue de la Côte-de-Nacre, CS 30001, 14000 Caen, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Pegoix
authors.affiliation: CHU de Caen, avenue de la Côte-de-Nacre, CS 30001, 14000 Caen, France.
authors.forename: Kelly
authors.initials: K
authors.lastname: Monthé-Sagan
authors.affiliation: CHU de Caen, avenue de la Côte-de-Nacre, CS 30001, 14000 Caen, France; EA 4650, université de Caen Basse-Normandie, esplanade de la Paix, CS 14032, 14000 Caen, France.
authors.forename: Ludovic
authors.initials: L
authors.lastname: Berger
authors.affiliation: Hôpital Raymond-Poincaré, 92380 Garches, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Fletcher
authors.affiliation: CHU de Caen, avenue de la Côte-de-Nacre, CS 30001, 14000 Caen, France; EA 4650, université de Caen Basse-Normandie, esplanade de la Paix, CS 14032, 14000 Caen, France.
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Hanouz
mesh_terms: D000328:Adult; D000368:Aged; D000701:Analgesics, Opioid / Q000627:therapeutic use; D000771:Anesthesia, Intravenous / Q000379:methods*; D018686:Anesthetics, Intravenous / Q000008:administration & dosage*; D062186:Arterial Pressure / Q000187:drug effects; D017558:Elective Surgical Procedures; D023381:Endpoint Determination; D019277:Entropy; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007430:Intraoperative Care; D008297:Male; D008875:Middle Aged; D059225:Nociception; D010098:Oxycodone / Q000627:therapeutic use; D010147:Pain Measurement / Q000379:methods*; D010149:Postoperative Pain / Q000453:epidemiology / Q000517:prevention & control; D010880:Piperidines / Q000008:administration & dosage*; D015742:Propofol; D011446:Prospective Studies; D000077208:Remifentanil; D014656:Vascular Surgical Procedures / Q000379:methods*; D055815:Young Adult
chemical_list: D000701:Analgesics, Opioid; D018686:Anesthetics, Intravenous; D010880:Piperidines; D010098:Oxycodone; D000077208:Remifentanil; D015742:Propofol
keywords: Analgesia/nociception index; Remifentanil; Total intravenous anaesthesia; Vascular surgery