title: The effects of water lubrication of tracheal tubes on post-intubation airway complications: study protocol for a randomized controlled trial.
abstract: Water is known to have lubricating properties, thus it is used for lubrication of tracheal tubes to reduce airway injuries caused by intubation. However, there is no definite evidence to substantiate the beneficial effects of lubricating tracheal tubes using water for attenuating airway injuries. Moreover, the lubrication pretreatment may cause contamination of the tube, leading to respiratory infections. Therefore, this trial aims to assess whether no pretreatment of tracheal tubes does not increase post-intubation airway complications as compared with water lubrication of tubes.
  
  
  
  This is a prospective, double-blind, single-center, parallel-arm, noninferiority, randomized controlled trial to be conducted in participants aged 20-80 years who are undergoing elective surgery under general anesthesia with orotracheal intubation. Participants are randomly assigned into one of two groups depending on whether intubation is performed using a tracheal tube lubricated with water (n = 150) or without any pretreatment (n = 150). The primary outcome is the incidence of sore throat at 0, 2, 4, and 24 h after surgery, which is analyzed with a noninferiority test. The secondary outcomes are the incidence and severity of postoperative hoarseness, oropharyngeal injuries, and respiratory infections.
  
  
  
  Because we hypothesized that lubricating tracheal tubes using water has no advantage in reducing airway injuries associated with intubation, we will compare the incidence of sore throat, which is the most common complaint after intubation, in a noninferiority manner. This is the first randomized controlled trial to investigate the possibly beneficial or harmful effects of lubricating tracheal tubes using water before intubation. We expect that this trial will provide useful evidence to formulate a protocol for preparing tracheal tubes before intubation.
  
  
  
  This trial is registered at ClinicalTrials.gov on 1 July 2015 ( NCT02492646 ).
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Republic of Korea.|Present Address: Department of Anesthesiology and Pain Medicine, Catholic University Hospital of Daegu, School of Medicine, Catholic University of Daegu, Daegu, Republic of Korea.
authors.forename: Eugene
authors.initials: E
authors.lastname: Kim
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Republic of Korea.
authors.forename: Seong Mi
authors.initials: SM
authors.lastname: Yang
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Republic of Korea.
authors.forename: So Jeong
authors.initials: SJ
authors.lastname: Yoon
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Republic of Korea.
authors.forename: Jae-Hyon
authors.initials: JH
authors.lastname: Bahk
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Republic of Korea. eongpa@empas.com.
authors.forename: Jeong-Hwa
authors.initials: JH
authors.lastname: Seo
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015505:Chest Tubes; D002985:Clinical Protocols; D004311:Double-Blind Method; D005260:Female; D006685:Hoarseness / Q000209:etiology; D006801:Humans; D007442:Intubation, Intratracheal / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods*; D054327:Lubricants / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D010612:Pharyngitis / Q000209:etiology; D011446:Prospective Studies; D012107:Research Design; D012141:Respiratory Tract Infections / Q000209:etiology; D012307:Risk Factors; D066106:Seoul; D013997:Time Factors; D016896:Treatment Outcome; D014867:Water / Q000008:administration & dosage*; D055815:Young Adult
chemical_list: D054327:Lubricants; D014867:Water
keywords: Airway management; Anesthesia; General; Intratracheal; Intubation; Lubrication; Water