Table 1
Characteristics of patients in difficult intubation cases (n=217)

Characteristic	Value
Age (yr)	55.3±14.2
Sex (male/female)	130 (59.9) / 87 (40.1)
Height (cm)	164.1±8.7
Weight (kg)	64.7±12.1
Body mass index (kg/m2)	23.9±3.6
Rheumatic arthritis	5 (2.3)
Ankylosing spondylitis	6 (2.8)
Previous history of difficult airway	23 (10.6)
Previous history of airway or neck surgery	20 (9.2)
Type of surgery
Emergency	28 (12.9)
Elective	189 (87.1)
ASA classification
I	47 (21.7)
II	160 (73.7)
III	10 (4.6)

Values are presented as mean±SD or number (%).
ASA, American Society of Anesthesiologist physical status.