Source: Meier et. al. Anesth Analg 2002; 94: 494-9.

Reviewer:  R. Prasad, MD

Summary:

• Chin lift (CL) and jaw thrust (JT) similarly effective
• Both improve glottic opening vs. unsupported airway
• Both further improved by addition of 10 cmH20 CPAP
• Each pt studied with unsupported airway x 2, and CL/JT with/without CPAP.
• POGO (percent of glottic opening) score: 100%, >50%, <50%, and 0%.
• 100% = all 4 larnygeal boundaries (anterior laryngeal commisure, vocal cords, posterior interarytenoid arch) visible
• POGO has better inter- and intrarater reliability than Cormack-Lehane grade of view
• Stridor Score: 1-nl, 2-stridor by stethoscope, 3-stridor audible, 4-no air mvmt
• Pooled data:

Methods:

• 40 ASA I-II 2-9yo for outpt GA in Basel, Switzerland
• 24 to evaluate CL, JT, CPAP on pharyngeal anatomy
• all 40 for video exam of larynx
• Midaz premed, halothane induction, IV, 1% ET halo
• std head position (110deg angle btwn table and line from lateral corner of eye to tragus)
• airway endoscopy mask used to allow nasal FOB exam while airway maintained; tip of scope placed at edge of soft palate
• all data collected with spont ventilation
• Sequence of studies (1min each)
• unsupported airway
• CL (1-handed)
• CL + CPAP (10cm H2O)
• unsupported
• JT (2-handed)
• JT + CPAP (10cm H2O)
• For each condition, recorded 1 min video, stridor score, HR, RR, and SpO2
• Videos analyzed in random order. Glottic opening by POGO score

• 2-9yo, 12.5-35kg
• HR, RR, SpO2 - no signif changes
• Stridor - POGO correlation: r=-0.37)
• POGO scores for unsupported were dif btwn 24 pts for ENT surgery and 16pts for other surgery
• CL, JT similarly effective in increasing POGO scores

• May have been better to randomize order of airway conditions
• Stridor data diff to interpret - some had adenotonsillary hypertrophy; this would be source of stridor, not glottic opening
• Why did they do 24 ENT pts, then 16 others, and group all data together?