title: Observational study of Mallampati changes after prone spinal surgery.
abstract: OBJECTIVE
  To evaluate airway changes in patients undergoing surgery in the prone position.
  
  
  METHODS
  Single-arm observational study.
  
  
  METHODS
  Patients between 18 to 65 years old, scheduled for prone spinal surgery; 74 patients were enrolled and 54 patients were analyzed.
  
  
  METHODS
  The initial airway examination was graded according to the Samsoon and Young modification of the Mallampati classification (MMP). Airway photographs were obtained in a standardized manner and were repeated 20 minutes after extubation. The photographs were then randomized.
  
  
  METHODS
  Subjects' age, gender, race, weight, duration of surgery, amount of crystalloid fluid given, and estimated blood loss were recorded. Three senior anesthesiologists who were blinded to the origin of the photographs analyzed and graded the airways.
  
  
  RESULTS
  All statistical tests showed significance between pre-MMP and post-MMP scores (P<0.001). There was no difference between pre and post interobserver MMP scores. The MMPs of 12 patients (22%) did not change and MMP scores were changed in 42 patients (78%): 30 (71%) patients by one class, 10 (24%) patients by two classes, and two patients (5%) by three classes. There was no correlation between patients whose MMP was changed and length of surgery or crystalloid administered.
  
  
  CONCLUSIONS
  Modified Mallampati scores increased in the majority of patients after spinal surgery in the prone position.
authors.affiliation: Department of Anesthesiology, University of Vermont, Fletcher Allen Health Care, Burlington, VT 05401, USA.
authors.forename: Elrond Yi Lang
authors.initials: EY
authors.lastname: Teo
authors.affiliation: Department of Anesthesiology, University of Vermont, Fletcher Allen Health Care, Burlington, VT 05401, USA.
authors.forename: Brendan S
authors.initials: BS
authors.lastname: Kelley
authors.affiliation: Department of Anesthesiology, University of Vermont, Fletcher Allen Health Care, Burlington, VT 05401, USA. Electronic address: ian.black@vtmednet.org.
authors.forename: Ian H
authors.initials: IH
authors.lastname: Black
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000077324:Crystalloid Solutions; D005260:Female; D006801:Humans; D007552:Isotonic Solutions / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D061646:Operative Time; D016684:Prone Position; D013131:Spine / Q000601:surgery*; D055815:Young Adult
chemical_list: D000077324:Crystalloid Solutions; D007552:Isotonic Solutions
keywords: Mallampati airway; Patient positioning; Spinal surgery