Risk factors for difficult administration of anesthesia:
(1) obstructive sleep apnea
(2) atlanto-axial subluxation
(3) heart disease (cardiomyopathy, septal hypertrophy with outflow obstruction, infiltration of a coronary artery with ischemia, mitral or tricuspid valve incompetence)
(4) chronic sinonasal infections with excessive upper respiratory secretions
(5) infiltration of soft tissues with enlargement of tongue, adenoids and/or tonsils
(6) short and immobile neck
(7) limited range of motion in cervical spine and temporomandibular joint
(8) tracheal narrowing
(9) tracheal collapse on neck flexion
(10) short-trunk dwarfism
(11) kyphoscoliosis and/or lumbar lordosis
(12) obstructive lung disease with reduced gas diffusion
Children with Hurler's syndrome and coarse facial features present the greatest difficulty.
