Diagnostic Accuracy of Capnography in Nasogastric Tube Placement

This study evaluates whether capnography — measuring carbon dioxide levels in exhaled breath — can accurately confirm that a nasogastric (NG) tube has been correctly placed in the stomach rather than accidentally in the lung. NG tubes are commonly inserted in hospital patients for feeding, medication delivery, and stomach decompression. Misplacement into the respiratory tract is a known but serious complication, and current standard confirmation methods (X-ray) are not always immediately available. Eligible participants are adults aged 18 or older admitted to hospitals (including general wards, ICUs, and rehabilitation units) who require NG tube insertion during the study period. Patients who are receiving emergency life-saving procedures at the time of recruitment are excluded. During tube insertion, capnography readings are recorded and compared against standard X-ray confirmation to assess accuracy. Misplaced NG tubes can cause fatal complications when feeds are inadvertently administered into the lung. If capnography proves reliable as a bedside confirmation method, it could replace or supplement X-ray in many settings — providing faster, cheaper, and radiation-free verification of tube placement and improving patient safety across hospitals worldwide.