Evaluation of the C-MAC Miller Video Laryngoscope Sizes 0 and 1 During Tracheal Intubation of Infants Less Than 10 kg

Abstract

Study Objective Video laryngoscopy has primarily been developed to assist in difficult airways. Using video laryngoscopy in pediatric airway management is an up-and-coming topic. The aim of the presented study was to compare the intubation conditions obtained when using the C-MAC video laryngoscope with Miller blades sizes 0 and 1 for standard direct laryngoscopy and indirect laryngoscopy in children weighing less than 10 kg. Design This was a prospective study. Setting The study was performed in a university hospital. Patients Following ethical approval, 86 infants weighing less than 10 kg and undergoing surgery under general anesthesia were studied prospectively. Intervention Indirect and direct laryngoscopy either with C-MAC Miller blade size 0 or size 1. Measurements First, direct laryngoscopy was performed, and the best obtained view was graded without looking at the video monitor. A second investigator blinded to the view obtained under direct laryngoscopy graded the laryngeal view on the video monitor. Time to intubation, intubation conditions, and intubation attempts were recorded. Results In infants less than 10 kg, intubation conditions were excellent. There were no significant differences between the use of Miller blade 0 or 1 in reference to Cormack-Lehane grade, time to intubation, time to best view, or intubation attempts. Comparing direct and indirect intubation conditions using either Miller blade 0 or 1 revealed that the use of indirect laryngoscopy provided a significantly better view (P < 0.05) of the vocal cords. In 3 infants weighing more than 8 kg, the Miller blade 0 was described as too short and narrow for intubation. Conclusions Both devices allowed for an excellent visualization of the vocal cords.

Comparative efficacy of C‐MAC® Miller videolaryngoscope versus McGrath® MAC size “1” videolaryngoscope in neonates and infants undergoing surgical procedures under general anesthesia: A prospective randomized controlled trial

“…We used size “1” blade of both the study devices as McGrath VL is available in only one infant size blade for use in neonates and infants. A previous study by Raimann et al had also demonstrated that both C‐MAC Miller size 0 or 1 blades resulted in excellent intubation conditions in infants <10 kg with similar glottic views, intubation times, and intubation attempts 20 . The difference in blade height of C‐MAC Miller 0 and 1 blade is only 0.9 mm (11.5 mm vs. 12.4 mm) while the difference in blade length is 20.5 mm (63 mm vs. 83.5 mm).…”

“…Several devices and intubation techniques have been described to improve the intubation times and success. The first attempt success and intubation times have been variably reported due to heterogeneity of VL devices as nonstandard blades have a high rate of technical difficulty 8,9,11,20 . VLs with blades similar to conventional DL blades like McGrath MAC and C‐MAC Miller are potentially easier to use as compared to nonstandard blades due to greater familiarity 10 .…”

“…4,19 The optimal laryngeal views can be obtained in children <2 years of age during DL with Miller size-1 blade either by directly lifting the epiglottis or placing the laryngoscope tip into the vallecula. 16 We 20 The difference in blade height of C-MAC Miller 0 and 1 blade is only 0.9 mm (11.5 mm vs. 12.4 mm) while the difference in blade length is 20.5 mm (63 mm vs. 83.5 mm). McGrath MAC size 1 is longer (blade length of 95 mm) and blade height (10 mm) is 2.4 mm less than C-MAC Miller size 1.…”

“…The first attempt success and intubation times have been variably reported due to heterogeneity of VL devices as nonstandard blades have a high rate of technical difficulty. 8,9,11,20 VLs with blades similar to conventional DL blades like McGrath MAC and C-MAC Miller are potentially easier to use as compared to nonstandard blades due to greater familiarity. 10 McGrath MAC and C-MAC VLs used in our study achieved high first attempt success in a reasonable timeframe with minimal hypoxemia, unlike previous studies evaluating airway management in neonates and infants.…”

“…and Elattar et al21 ) and DL using C-MAC Miller blade (Raimann et al20 and Elattar et al20 ) in children. McGrath VL provided better laryngeal views (CL grade I; 95% vs. 74%, p = .013) than DL in children aged 1-10 years in a study by Kim et al22 In our study, C-MAC resulted in 100% POGO score in 80% cases, compared to only 41% patients with McGrath MAC without any optimal external laryngeal manipulation (p = .039).…”