title: Causes of sore throat after intubation: a prospective observational study of multiple anesthesia variables.
abstract: BACKGROUND
  Sore throat is common after intubation for surgery. This observational study investigated cuff pressure and a large range of clinical covariates to explore the etiology of sore throat.
  
  
  METHODS
  Approximately 24 hours after surgery six questions relating to pain, upper airway symptoms and sore throat were delivered to patients who had undergone intubation. Sore throat was correlated with demographics, anesthesia variables and cuff pressure (measured for a subset of patients).
  
  
  RESULTS
  Sore throat was reported by 270/518 (52%) patients with VAS Score 45.9±25.1 (range 0-100). Sore throat patients were significantly younger, had a lower ASA status, were more frequently female, had shorter surgeries and lower nitrous oxide exposure, had a higher proportion of smaller tracheal tubes (7.5 mm internal diameter vs. 8 mm), had a higher incidence of nasogastric drainage, higher propofol doses and a higher usage of ketorolac. Decreasing age (odds ratio 0.976, 95% confidence intervals 0.961-0.992, P=0.003) and the presence of a nasogastric tube when the questionnaire was delivered (OR 1.83, 95% CI: 1.06-3.14, P=0.03) remained significant predictors of sore throat on multivariate analysis. Mean cuff pressure (measured for 160 patients) was 56.8±41.9 mmHg. Cuff pressure was similar amongst patients with and without sore throat (57±46 vs. 53±38 mmHg, P=0.58). There was no correlation between cuff pressure and severity of sore throat (r=0.004, P=0.37).
  
  
  CONCLUSIONS
  Only age and the presence of a nasogastric tube after surgery were significant predictors for sore throat. This result contradicts most other studies of cuff pressure where fewer covariates were measured.
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, Hadassah Hebrew University Medical Center, Jerusalem, Israel - levinp@netvision.net.il.
authors.forename: Phillip D
authors.initials: PD
authors.lastname: Levin
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, Hadassah Hebrew University Medical Center, Jerusalem, Israel.
authors.forename: Chrysostomou
authors.initials: C
authors.lastname: Chrysostomos
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, Hadassah Hebrew University Medical Center, Jerusalem, Israel.
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Ibarra
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, Hadassah Hebrew University Medical Center, Jerusalem, Israel.
authors.forename: Stephan
authors.initials: S
authors.lastname: Ledot
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, Hadassah Hebrew University Medical Center, Jerusalem, Israel.
authors.forename: Daigo
authors.initials: D
authors.lastname: Naito
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, Hadassah Hebrew University Medical Center, Jerusalem, Israel.
authors.forename: Charles
authors.initials: C
authors.lastname: Weissman
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, Hadassah Hebrew University Medical Center, Jerusalem, Israel.
authors.forename: Alexander
authors.initials: A
authors.lastname: Avidan
mesh_terms: D000758:Anesthesia; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal / Q000009:adverse effects* / Q000379:methods; D017214:Laryngeal Masks; D008297:Male; D008875:Middle Aged; D010612:Pharyngitis / Q000209:etiology*; D011446:Prospective Studies