title: Emergence times and airway reactions in general laryngeal mask airway anesthesia: study protocol for a randomized controlled trial.
abstract: BACKGROUND
  The use of a laryngeal mask airway (LMA) in appropriate patients supports fast-track anesthesia with a lower incidence of postoperative airway-connected adverse events. Data on the most favorable anesthetic in this context, with the lowest rate of upper airway complications and fast emergence times, are controversial and limited. Desflurane seems to match these criteria best, but large randomized controlled trials (RCTs) with a standardized study protocol are lacking. Therefore, we aim to compare desflurane with other commonly used anesthetics, sevoflurane and propofol, in a sufficiently powered RCT. We hypothesize that desflurane is noninferior regarding the frequency of upper airway events and superior regarding the emergence times to sevoflurane and propofol.
  
  
  METHODS
  A total of 351 patients undergoing surgery with an LMA will be included in this prospective, randomized, double-blind controlled, multicenter clinical trial. The patients will be randomly assigned to the three treatment arms: desflurane (n = 117), sevoflurane (n = 117), and propofol (n = 117). The emergence time (time to state the date of birth) will be the primary endpoint of this study. The secondary endpoints include further emergence times, such as time to open eyes, to remove LMA, to respond to command and to state name. Additionally, we will determine the frequency of cough and laryngospasm, measured intraoperatively and at emergence. We will assess the postoperative recovery on the first postoperative day via the Postoperative Quality Recovery Scale.
  
  
  CONCLUSIONS
  Despite increasing importance of cost-effective and safe anesthesia application, we lack proof for the most advantageous anesthetic agent, when an LMA is used. There are only a few RCTs comparing desflurane to other commonly used anesthetics (sevoflurane, propofol and isoflurane) in patients with LMA. These RCTs were conducted with small sample sizes, huge interstudy variability, and some also showed strong biases. The present multicenter RCT will provide results from a large sample size with a standardized study protocol and minimized bias, which is feasible in the clinical routine. Furthermore, we will expand our knowledge regarding the most favorable recovery on the first postoperative day, which impacts patients' comfort after surgery.
  
  
  BACKGROUND
  EudraCT Identifier: 2014-003810-96, 5 September 2014 ClinicalTrials.gov: NCT02322502, December 2014.
authors.affiliation: Department of Anesthesiology, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany. astevanovic@ukaachen.de.
authors.forename: Ana
authors.initials: A
authors.lastname: Stevanovic
authors.affiliation: Department of Anesthesiology, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany. rrossaint@ukaachen.de.
authors.forename: Rolf
authors.initials: R
authors.lastname: Rossaint
authors.affiliation: Department of Medical Informatics, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany. AKeszei@mi.rwth-aachen.de.
authors.forename: András P
authors.initials: AP
authors.lastname: Keszei
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, Martha-Maria Hospital, Röntgenstraße 1, 06120, Halle (Saale), Germany. Harald.Fritz@martha-maria.de.
authors.forename: Harald
authors.initials: H
authors.lastname: Fritz
authors.affiliation: Department of Anesthesiology, University Hospital Ulm, Albert-Einstein-Allee 23, 89081, Ulm, Germany. gebhard.froeba@uni-ulm.de.
authors.forename: Gebhard
authors.initials: G
authors.lastname: Fröba
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, Klinikum am Steinenberg, Steinenbergstr. 31, 72764, Reutlingen, Germany. puehringer_f@klin-rt.de.
authors.forename: Friedrich
authors.initials: F
authors.lastname: Pühringer
authors.affiliation: Department of Anesthesiology, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany. mcoburn@ukaachen.de.
authors.forename: Mark
authors.initials: M
authors.lastname: Coburn
mesh_terms: D000762:Anesthesia Recovery Period; D000768:Anesthesia, General / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D000769:Anesthesia, Inhalation / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D018685:Anesthetics, Inhalation / Q000008:administration & dosage* / Q000009:adverse effects; D018686:Anesthetics, Intravenous / Q000008:administration & dosage* / Q000009:adverse effects; D002985:Clinical Protocols; D003243:Consciousness / Q000187:drug effects; D000077335:Desflurane; D004311:Double-Blind Method; D005858:Germany; D006801:Humans; D007530:Isoflurane / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D017214:Laryngeal Masks; D008738:Methyl Ethers / Q000008:administration & dosage* / Q000009:adverse effects; D011183:Postoperative Complications / Q000209:etiology; D015742:Propofol / Q000008:administration & dosage* / Q000009:adverse effects; D011446:Prospective Studies; D020127:Recovery of Function; D012107:Research Design; D012307:Risk Factors; D000077149:Sevoflurane; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D008738:Methyl Ethers; D000077149:Sevoflurane; D000077335:Desflurane; D007530:Isoflurane; D015742:Propofol