Abstract
Preformed cuffed oral endotracheal tubes are widely used to intubate children undergoing oral surgery. To evaluate the efficacy and safety of oral Ring-Adair-Elwyn (RAE) Microcuff® pediatric endotracheal tubes, we retrospectively investigated the endotracheal tube exchange rate and associated complications in Japanese children younger than 2 years of age undergoing cheiloplasty or palatoplasty. The exchange rate was 3.5%, and although unplanned extubations occurred in 2 patients, no severe complications were observed. Our results suggest that oral RAE Microcuff® tubes are effective and safe for intubating Japanese children younger than 2 years of age, with a low tube exchange rate and minor complications.
Keywords: Pediatric anesthesia, Cuffed tracheal tube, Tube size, Oral surgery
Microcuff® pediatric endotracheal tubes (AVANOS, Alpharetta, GA) have a short, cylindrically shaped cuff comprising a micro thin polyurethane membrane that seals the airway at ultra-low pressure. The high-volume, low-pressure cuff is designed to minimize tracheal trauma in children and has been reported to prevent air leaks and channeling.1 Preformed oral Ring-Adair-Elwyn (RAE) Microcuff® tubes have been used for oral and facial surgery in Japan since 2015 (the Figure). Tube size is generally left to the discretion of the anesthesiologist in combination with the manufacturer's sizing recommendations as the common age formula is not applicable to patients <24 months of age. This retrospective study evaluated the efficacy and safety of Microcuff® oral RAE tubes in Japanese children <2 years of age undergoing oral surgery.
Preformed oral RAE Microcuff® endotracheal tube.
Patients 2 to 24 months of age who underwent cheiloplasty or palatoplasty under general anesthesia at Osaka University Dental Hospital between April 2016 and October 2017 were included. The patients' demographic information, tube sizes, tube exchange rates, and associated complications were reviewed.
Overall, 173 cases were included (the Table). Microcuff® tubes were deemed too large for premature and low birthweight children and were replaced with smaller or uncuffed oral RAE tubes in 6 cases (3.5%). Microcuff® tubes larger than recommended by the manufacturer were used in palatoplasty patients >18 months to prevent bleeding into the trachea. Although no severe complications were observed, 4 patients developed complications. These included unplanned extubations in two 11-month-old patients intubated using 3.5-mm Microcuff® tubes, which were thought to have resulted from extension of the head and neck during intraoral disinfection before palatoplasty. One patient experienced postoperative hoarseness. Kinking of the endotracheal tube nearest the proximal end-anesthesia circuit connector, attributed to the use of a Dingman mouth gag, was observed in 1 patient.
Patient Demographics and Study Data*
|
Total |
Age, mo |
|||
| 0–8 |
8–18 |
18–24 |
||
| Number of patients | 173 | 82 | 69 | 22 |
| Age, mo | 9.6 ± 6.3 | 3.5 ± 0.7 | 13.8 ± 2.7 | 19.1 ± 0.9 |
| Weight, kg | 7.5 ± 1.8 | 5.9 ± 0.8 | 8.7 ± 1.1 | 9.5 ± 1.1 |
| Height, cm | 67.1 ± 11.0 | 61.1 ± 2.7 | 73.0 ± 8.8 | 77.0 ± 2.3 |
| Sex, female/male | 87/86 | 41/41 | 34/35 | 12/10 |
| Operation time, min | 77 ± 30 | 66 ± 27 | 86 ± 27 | 92 ± 31 |
| Tube type and size, #ID | ||||
| Microcuff RAE #3.0 | 71 | 70 | 1 | 0 |
| Microcuff RAE #3.5 | 70 | 10 | 51 | 9 |
| Microcuff RAE #4.0 | 29 | 0 | 16 | 13 |
| Uncuffed RAE #3.0 | 2 | 2 | 0 | 0 |
| Uncuffed RAE #3.5 | 1 | 0 | 1 | 0 |
| Complications | 4 | 0 | 2 | 2 |
| Tube exchange | 6 | 2 | 3 | 1 |
Data are presented as mean ± SD or number of patients. ID, internal diameter of the endotracheal tube (mm); Microcuff RAE, Microcuff® pediatric oral RAE endotracheal tube; Uncuffed RAE, uncuffed pediatric oral RAE endotracheal tube.
At our institution, an average of 1.47 uncuffed tubes are utilized per patient <2 years of age when an age-based formula is used to size oral endotracheal tubes.2 Exchange rates for the Microcuff® tubes used in this study (3.5%) were almost equivalent to those for uncuffed tubes in previous reports (1.3–4%).3 Therefore, Microcuff® tubes could reduce exchanges due to improper sizing based on age alone. Although the manufacturer recommends a 3.5 Microcuff® tube for patients 18 to 24 months, a 4.0 tube was selected by Weiss et al.4 In our study, 4.0 Microcuff® tubes were used more often than 3.5 tubes. Smaller size is generally preferred when using preformed cuffed tubes compared with preformed uncuffed tubes, potentially resulting in a shorter insertion length. Consequently, as the position of the tube tip and cuff might be inappropriately high when using preformed cuffed tubes, we selected their sizes based on the insertion depth to prevent unplanned extubations caused by head and neck extension.5 These results suggest that the approach of Weiss et al4 is appropriate when considering the impact of head movement on endotracheal tube migration.
In conclusion, preformed oral RAE Microcuff® tubes are a safe and effective option for intubating Japanese children <2 years of age undergoing cheiloplasty or palatoplasty. However, clinicians should consider potential problems regarding tube sizing and proper positioning of the tube tip and cuff when using Microcuff® tubes.
This research was originally published in the Journal of the Japanese Dental Society of Anesthesiology. 2019;47(4):152–154.
REFERENCES
- 1.Dullenkopf A, Schmitz A, Gerber AC, Weiss M. Tracheal sealing characteristics of pediatric cuffed tracheal tubes. Paediatr Anaesth. 2004;14:825–830. doi: 10.1111/j.1460-9592.2004.01316.x. [DOI] [PubMed] [Google Scholar]
- 2.Hanamoto H, Maegawa H, Inoue M, Oyamaguchi A, Kudo C, Niwa H. Age-based prediction of uncuffed tracheal tube size in children to prevent inappropriately large tube selection: a retrospective analysis. BMC Anesthesiol. 2019;19:141. doi: 10.1186/s12871-019-0818-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Salgo B, Schmitz A, Henze G, et al. Evaluation of a new recommendation for improved cuffed tracheal tube size selection in infants and small children. Acta Anaesthesiol Scand. 2006;50:557–561. doi: 10.1111/j.1399-6576.2006.01003.x. [DOI] [PubMed] [Google Scholar]
- 4.Weiss M, Dullenkopf A, Fischer J, Keller C, Gerber A; European Paediatric Endotracheal Intubation Study Group. Prospective randomized controlled multi-centre trial of cuffed or uncuffed endotracheal tubes in small children. Br J Anaesth. 2009;103:867–873. doi: 10.1093/bja/aep290. [DOI] [PubMed] [Google Scholar]
- 5.Weiss M, Knirsch W, Kretschman O, et al. Tracheal tube-tip displacement in children during head-neck movement—a radiological assessment. Br J Anaesth. 2006;96:486–449. doi: 10.1093/bja/ael014. [DOI] [PubMed] [Google Scholar]