Ultrasound to confirm gastric tube placement in prehospital management

BackgroundIn emergency medicine, the gastric tube (GT) has many purposes, however in prehospital settings, the only indication is gastric decompression. To date, there is lack of recommendation on the diagnostic methods to verify correct GT placement in prehospital. The aim of this study is to estimate diagnostic accuracy of ultrasound in confirming gastric tubes placement in a prehospital setting.MethodThis was a prospective multicentre study conducted in two French towns (Marseille and Grasse) over a one-year period from May 2010 to May 2011.ResultsOne hundred and thirty patients were included in the study with an M/F sex ratio of 77/53 and a mean age of 55.7 ± 19.8 years. The GT position was confirmed by ultrasound, with direct visualization in the gastric area in 116 of the 130 patients. In 14 cases, the ultrasound failed to visualize the tip of the GT; these results were due in 2 cases to gas interposition and in 12 cases the GT was shown by final X-ray to be located in the end of the oesophagus. Direct visualization by ultrasound thus has a sensitivity of 98.3% [94–99.5] and a specificity of 100% [75.7–100], a positive predictive value of 100% and a negative predictive value of 85.7%, Youden's index of 0.98. GT size affects ultrasound visualization; the larger the GT, the easier it is to see.ConclusionBedside ultrasound thus appears to constitute an effective and reliable diagnostic procedure for confirming correct gastric tube placement in prehospital settings.