Appropriateness of endotracheal tube size and insertion depth in children undergoing air medical transport

Objectives: Guidelines for pediatric endotracheal tube (ETT) size and inser tion depth are important in the helicopter EMS (HES) setting, where intubat ed patients are frequently transported by a non-physician flight crew provi ding protocol-based care in an environment noted for Limitations in clinica l airway assessment. The objectives of this study were to characterize, in a HEMS pediatric population, the frequency of compliance with guideline-rec ommended ETT size and insertion depth, and to test for association between guideline noncompliance and subsequent receiving hospital adjustment of ETT size or insertion depth. Design: This retrospective review analyzed 216 consecutive pediatric (age < 14) scene and interfacility HEMS transports, of patients intubated before o r during HEMS transport, by an urban two-helicopter HEMS service providing protocol-based care with a nurse/paramedic crew configuration. Patients wer e transported to one of three receiving academic pediatric referral centers . Pediatric Advanced Life Support(PALS) criteria for ETT size and insertion depth were used to assess guideline-appropriateness of pediatric ETTs. Rec eiving hospital records were reviewed to determine if post-transport ETT si ze or lipline adjustment were associated with guideline-appropriateness of size and lipline during HEMS transport. Univariate (chi-square and Fisher's exact) and multivariate (logistic regression) statistics were used to asse ss and control for the following covariates: intubator group (physician, fl ight crew, ground EMS), transport year, sex, age, transport type (scene ver sus interfacility), and receiving hospital. For all analyses, statistical s ignificance was set at the 0.05 level. Results: The initial ETT size was within 0.5 mm of guideline-recommended si zes in 178 (83.6%) of the 213 patients for whom this data were available. I nappropriate sized ETTs were nearly always (32 of 35, 91.4%) too small. Com pared to initial ETTs placed by ground EMS personnel, initial ETTs placed b y flight crew or physicians mere more likely to be appropriate as defined b y guidelines (P = .008 and .032, respectively). Receiving hospitals changed the ETT size in 18 (8.3% of 216) cases. Receiving hospital ETT size change was more likely with later transport year (P = .018) and less likely in pa tients over 2 years of age (P = .03); there was no significant association between receiving hospital ETT size change and intubator group (P > .22) or guideline-appropriateness of ETT size (P = 0.94). The initial ETT insertio n depth was within 1 cm of the guideline-recommended lipline in 86 (43.2%) of the 199 patients for whom this data were available. Inappropriate liplin es were almost always (109 of 113, 96.5%) too deep. Compared to initial ETT liplines determined by ground EMS personnel, initial liplines determined b y Right crew (P = .007), but not physician (P = .47) were more likely to be appropriate as defined by guidelines. Receiving hospitals changed the ETT insertion depth in 72 (33.3% of 216) cases. Receiving hospital lipline chan ge was more likely (P = .03) in patients older than 2 years of age, but was not associated with intubator group (P = .75) or lipline guideline-appropr iateness (P = .35). Conclusions: As judged by frequently used guidelines, pediatric ETTs are of ten too small and commonly inserted too deep. However, this retrospective s tudy, limited by lack of clinical correlation for ETT size and insertion de pth, failed to find an association between lack of ETT size or lipline guid eline compliance and subsequent ETT adjustment at receiving pediatric cente rs. This study's findings, which should be confirmed with prospective inves tigation, cast doubt upon the utility of pediatric ETT size/lipline guideli nes as strict clinical or quality assurance tools for use in pediatric airw ay management.