When assessing the pH of secretions from a client’s NG tube, what pH range should the nurse expect to confirm correct tube placement?

When assessing the pH of secretions from a client’s NG tube to confirm correct tube placement, a pH of around 4.0 is expected. This lower pH indicates the presence of gastric contents, which are typically acidic due to gastric acid secretion (primarily hydrochloric acid).

The rationale behind expecting a pH around 4.0 is based on the physiological environment of the stomach. Gastric juices usually have a pH ranging from 1.5 to 3.5, but the secretions that can be aspirated through an NG tube will often have a pH closer to 4 due to dilution and the presence of other substances. A pH that is higher than this range (like 5.0, 6.0, or 7.0) could indicate the presence of contents from the intestines or tracheobronchial secretions, which are less acidic, or suggests that the tube may not be correctly placed in the stomach. Therefore, a pH of 4.0 serves as a reliable indicator for confirming that the NG tube is correctly positioned in the stomach.