The Royal Marsden Hospital Manual of Clinical Nursing Procedures - Lisa Dougherty [273]
4 Mark the distance to which the tube is to be passed by measuring the distance on the tube from the patient’s earlobe to the bridge of the nose plus the distance from the earlobe to the bottom of the xiphisternum.
To indicate the length of tube required for entry into the stomach. E
5 Wash hands with bactericidal soap and water or bactericidal alcohol handrub, and assemble the equipment required.
Hands must be cleansed before and after patient contact to minimize cross-infection (Fraise and Bradley 2009, E).
Procedure
6 Check the nostrils are patent by asking the patient to sniff with one nostril closed. Repeat with the other nostril.
To identify any obstructions liable to prevent intubation. E
7 Lubricate about 15–20 cm of the tube with a thin coat of lubricating jelly that has been placed on a topical swab.
To reduce the friction between the mucous membranes and the tube. E
8 Insert the proximal end of the tube into the clearer nostril and slide it backwards and inwards along the floor of the nose to the nasopharynx. If an obstruction is felt, withdraw the tube and try again in a slightly different direction or use the other nostril.
To facilitate the passage of the tube by following the natural anatomy of the nose. E
9 As the tube passes down into the nasopharynx, ask the patient to start swallowing and sipping water, enabling the tube to pass into the oesophagus.
To focus the patient’s attention on something other than the tube. The swallowing action closes the glottis and the cricopharyngeal sphincter opens, enabling the tube to pass into the oesophagus (Groher 1997, R5).
10 Advance the tube through the pharynx as the patient swallows until the tape-marked tube reaches the point of entry into the external nares. If the patient shows signs of distress, for example gasping or cyanosis, remove the tube immediately.
Distress may indicate that the tube is in the bronchus. However, absence of distress is insufficient for detecting a misplaced tube (NPSA 2005, C).
11 Secure the tube to the nostril with adherent dressing tape, for example Elastoplast, or an adhesive nasogastric stabilization/securing device. If this is contraindicated, a hypoallergenic tape should be used. An adhesive patch (if available) will secure the tube to the cheek.
To hold the tube in place. To ensure patient comfort. E
Postprocedure
12 Check the position of the tube to confirm that it is in the stomach by using the following methods.
To confirm placement of radiopaque nasogastric tube. X-ray of radiopaque tubes is the most accurate confirmation of position and is the method of choice in patients with altered anatomy, those who are aspirating or are unconscious with no gag reflex (NPSA 2005, C).
Either
Take an X-ray of chest and upper abdomen.
Or
Aspirate 0.5–1 mL of stomach contents and test pH on indicator strips (NPSA 2005, C; Rollins 1997). When aspirating fluid for pH testing, wait at least 1 hour after a feed or medication has been administered (either orally or via the tube). Before aspirating, flush the tube with 20 mL of air to clear other substances (Metheny et al. 1993). A pH level of 5.5 is unlikely to be pulmonary aspirates and it is considered appropriate to proceed to feed through the tube (Metheny and Meert 2004, NPSA 2005). Indicator strips should have gradations of 0.5 or paper with a range of 0–6 or 1–11 to distinguish between gastric acid and bronchial secretions (NPSA 2005, C). To prove an accurate test result because the feed or medication may raise the pH of the stomach. Wait at least 1 hour before aspirating to enable the feed or medication to be absorbed, otherwise an inaccurate test will be obtained (NPSA 2005, C).
If a pH of 6.0 or above is obtained or there is doubt over the result in the range of pH 5–6 then feeding must not commence. The nasogastric tube may need to be repositioned or checked with an X-ray. There is an increased risk of the nasogastric tube being incorrectly placed (NPSA 2005, C).
13 The following methods must