Yes, both air and pH can be assessed during the evaluation of a nasogastric (NG) tube placement, but they serve different purposes and are measured in different ways.
-
pH Measurement: To confirm the correct placement of an NG tube, the aspirate fluid obtained from the stomach can be tested for pH. Normal gastric pH is typically less than 5.5 (though it may be less acidic in some cases). A pH test is a common method used to ascertain whether the tube is in the stomach rather than in the lungs or esophagus.
-
Air: The presence of air can be assessed by gently injecting air through the tube while listening with a stethoscope over the stomach. If you hear a "whoosh" sound, it suggests that the tube is in the stomach. However, this method is less reliable than pH testing and is not commonly used alone to confirm placement due to the potential for false positives.
In practice, the measurement of pH is favored and is a more reliable and validated method to confirm NG tube placement compared to air injection. Therefore, it is generally recommended to utilize pH measurement alongside clinical judgment when confirming NG tube placement.