The feasibility of determining the position of an endotracheal tube in neonates by using bedside ultrasonography compared with chest radiographs

Abstract

Background. Neonates in our neonatal intensive care unit (NICU) receive a large amount of radiation with X-rays (XRs) being done daily, even more often with reintubation, repositioning of endotracheal tubes (ETTs) and confirmation thereof, which has been our NICU policy for many years.
Objective. To investigate the feasibility of determining the position of ETTs in neonates by using bedside ultrasonography (BUS), and to compare the results with those obtained from chest XR (CXR) findings.
Methods. A prospective, cross-sectional study was done on intubated neonates in the NICU at Universitas Academic Hospital, Bloemfontein, to determine the position of ETTs by using BUS.
Results. Thirty intubated patients included in this study had a median age of 13.5 days and a median weight of 1.6 kg. Ninety-three per cent of ETT placements were considered optimal when visualised by BUS, while 73.3% were considered to be placed optimally when CXR was viewed. When CXR and BUS findings were compared regarding optimal placing, the agreement was poor (κ=0.10; 95% confidence interval –0.2 - 0.4). In four patients, the distance from the aortic arch to the tip of the ETT was outside the expected range of 1.5 - 2.2 cm: in two patients it was <1.5 cm (6.7%) and in the other two >2.25 cm (6.7%). BUS measurements were done mainly in extended head (53.3%) or neutral (36.7%) position.
Conclusion. Although poor agreement between CXR and BUS findings was obtained, possibly because of handling of patients with secondary shifting of ETTs, BUS was found not to be comparable with CXR, but an alternative feasible method to determine the optimal position of ETTs in the trachea in neonates when using other reference points, with the added advantage of no radiation exposure.