title: Efficacy of a single dose of dexmedetomidine for cough suppression during anesthetic emergence: a randomized controlled trial.
abstract: OBJECTIVE
  Maintenance of a remifentanil infusion during anesthetic emergence has been reported to decrease the incidence of coughing and thereby help to ensure a smooth emergence. It may, however, cause respiratory depression and possibly delay emergence. The purpose of this study was to investigate the effect of a single dose of dexmedetomidine combined with a low-dose remifentanil infusion on cough suppression during emergence from general anesthesia.
  
  
  METHODS
  American Society of Anesthesiologists physical status I-II adults undergoing elective thyroidectomy under sevoflurane anesthesia were recruited and randomly allocated to receive either dexmedetomidine 0.5 μg·kg(-1) iv (Group D, n = 70) or saline (Group S, n = 71), each combined with a low-dose remifentanil infusion ten minutes before the end of surgery. Coughing was assessed using a four-point scale. The respiratory rate (RR), heart rate (HR), and mean arterial pressure were also recorded.
  
  
  RESULTS
  The incidence of coughing was lower in Group D than in Group S (64% vs 91%, respectively; mean difference 27%; 95% confidence interval [CI] 13 to 41; P < 0.001). The median cough grade at extubation was also lower in Group D. Mean arterial pressure and HR were elevated in Group S during tracheal extubation but were similar to baseline values in Group D. There was no difference in RR between the two groups throughout the study. A small delay in extubation was observed in Group D (3 minutes longer than Group S; 95% CI 2 to 4; P < 0.001).
  
  
  CONCLUSIONS
  Compared with an infusion of low-dose remifentanil alone, the addition of a single dose (0.5 μg·kg(-1)) of dexmedetomidine during emergence from sevoflurane-remifentanil anesthesia was effective in attenuating coughing and hemodynamic changes and did not exacerbate respiratory depression after thyroid surgery. This trial was registered at Clinicaltrial.gov, identifier: NCT01774305.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Gangnam Severance Hospital, Yonsei University College of Medicine, 211 Eonju-ro, Gangnam-gu, Seoul, 135-720, Republic of Korea.
authors.forename: Jeong Soo
authors.initials: JS
authors.lastname: Lee
authors.forename: Seung Ho
authors.initials: SH
authors.lastname: Choi
authors.forename: Young Ran
authors.initials: YR
authors.lastname: Kang
authors.forename: Yunhee
authors.initials: Y
authors.lastname: Kim
authors.forename: Yon Hee
authors.initials: YH
authors.lastname: Shim
mesh_terms: D058647:Adrenergic alpha-2 Receptor Agonists / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D000328:Adult; D060666:Airway Extubation; D000762:Anesthesia Recovery Period; D000768:Anesthesia, General / Q000379:methods*; D062186:Arterial Pressure / Q000187:drug effects; D003371:Cough / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D020927:Dexmedetomidine / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D004311:Double-Blind Method; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D015994:Incidence; D008297:Male; D008738:Methyl Ethers / Q000008:administration & dosage; D008875:Middle Aged; D010880:Piperidines / Q000008:administration & dosage; D000077208:Remifentanil; D000077149:Sevoflurane; D013965:Thyroidectomy / Q000379:methods
chemical_list: D058647:Adrenergic alpha-2 Receptor Agonists; D008738:Methyl Ethers; D010880:Piperidines; D000077149:Sevoflurane; D020927:Dexmedetomidine; D000077208:Remifentanil