The nurse has just inserted a nasogastric (NG) feeding tube into a patient.What should the nurse do to definitely ascertain that the tube is in the stomach or in the intestine?

A) Test the pH of the contents.
B) Use a carbon dioxide sensor.
C) Lower the head of the bed to 15 degrees.
D) Obtain an order for a chest radiograph.

The most reliable method of feeding tube verification is a chest radiograph (chest x-ray).Gastric and intestinal pH measurements have been shown to differentiate tube placement,with the stomach having a lower pH than the intestines.This helps to ensure that the tube is beyond the pylorus,theoretically reducing the risk for aspiration.This method is helpful before and after radiological confirmation.Carbon dioxide sensors are helpful in determining tube placement between the stomach and the lung.A small plastic piece with an embedded yellow sensor is attached to the end of the feeding tube;the sensor changes color when carbon dioxide is present.Investigators have shown that this reduces the incidence of inadvertent pulmonary placement.This method is helpful before and after radiological confirmation.Elevation of the head of the bed to a minimum of 30 degrees is a simple method used to keep the risk for aspiration at a minimum.The nurse is instrumental in achieving this goal.This method does not ascertain placement but may be useful in preventing aspiration.