Indications and Contraindications for Nasogastric Intubation
A nasogastric tube is a flexible lumen passed through the nasopharynx into the stomach. Nurses encounter this procedure frequently in Nigerian clinical settings for various therapeutic and diagnostic goals.
- Decompression: Removal of gastric secretions and swallowed air in bowel obstruction or ileus.
- Enteral nutrition: Provision of nutrients when oral intake is impossible.
- Medication administration: Delivering drugs directly to the gastrointestinal tract.
- Gastric lavage: Washing out toxic substances after ingestion.
Absolute and relative contraindications must be evaluated carefully before insertion. Severe mid-face trauma or basilar skull fractures pose a high risk of intracranial tube placement. Esophageal strictures, severe coagulation disorders, and recent esophageal surgery also require extreme caution or alternative routes.
Pre-Procedure Preparation and Equipment
Preparing for nasogastric tube insertion minimizes patient distress and procedural complications. Gather all necessary items before approaching the bedside:
- Nasogastric tube: Appropriate size (typically 14-16 French for adults, smaller for children).
- Lubricant: Water-soluble jelly to ease passage and reduce mucosal friction.
- Tape and securement device: To anchor the tube firmly to the nose.
- Stethoscope and syringe: For placement verification checks.
- Glass of water with a straw: To help the patient swallow during insertion, if conscious.
- Emesis basin and tissues: For managing inevitable secretions or gagging.
Explain the procedure clearly to the patient or caregivers to gain cooperation. Position the conscious patient in a high Fowler's position, aligning the neck naturally to facilitate swallowing.
Step-by-Step Insertion Technique
Inserting a nasogastric tube requires steady hands, patience, and close monitoring of patient responses. Measure the correct insertion length from the tip of the nose, to the earlobe, and down to the xiphoid process, marking the spot with tape.
Lubricate the distal tip of the tube generously. Gently insert the tube through the nostril, aiming downward and backward toward the ear. If resistance is met, do not force it; withdraw slightly and try the other nostril. As the tube reaches the nasopharynx, ask the patient to swallow sips of water. Advance the tube with each swallow until the predetermined mark is reached. If the patient begins to cough, gasp, or turn cyanotic, immediately pull the tube back because it has likely entered the trachea.
Verifying Tube Placement
Confirms correct positioning before any fluid, medication, or food enters the stomach. Relying on a single method is unsafe; nurses use a combination of checks.
- Radiography: The gold standard. An abdominal X-ray provides definitive confirmation of gastric placement.
- Aspirate pH testing: Gastric fluid is typically acidic, with a pH of 5.5 or lower, whereas respiratory secretions are alkaline.
- Visual inspection of aspirate: Observing grassy green, tan, or clear fluid.
Auscultation (listening over the epigastric region while pushing air through the tube) is historically common but unreliable because air entering the intestine or pharynx can mimic a whoishing sound. Never use auscultation as the sole verification method.
Routine Maintenance and Daily Care
Maintaining a secure and clean nasogastric site prevents complications such as nasal necrosis, sinusitis, and accidental dislodgement.
- Secure the tube properly to the nose with hypoallergenic tape, ensuring it does not press tightly against the naris margin.
- Clean the nostril daily with warm water and mild soap to remove crusting secretions.
- Change the tape fixation regularly or whenever it becomes loose from skin oils or sweat.
- Provide frequent oral hygiene, including mouthwashes and lip balm, because patients with nasogastric tubes breathe through their mouths and develop dry mucous membranes quickly.
Administering Feedings and Medications
Delivering nutrition and medicines via a nasogastric tube requires strict adherence to infection control and safety protocols.
- Check residual volume: Aspirate gastric contents before feeding. High residuals indicate delayed gastric emptying.
- Elevate head of bed: Keep the patient at least 30 to 45 degrees elevated during feeding and for 30 minutes after to prevent aspiration.
- Flush the tube: Use sterile or clean water before and after medication administration or feedings to prevent clogging.
- Crush medications properly: Ensure tablets are thoroughly crushed and dissolved in water if formulation permits, administering drugs separately and flushing between each.
Troubleshooting Tube-Related Problems
Nurses frequently manage minor complications associated with indwelling nasogastric tubes.
- Clogged tubes: Often caused by crushed medications or thick formulas. Flush with warm water using a push-pause motion. Avoid using force or wire stylets which can puncture the tube.
- Nausea and vomiting: Usually indicate delayed gastric emptying or tube displacement into the duodenum. Check residual volumes and reposition if necessary.
- Tube displacement: If markings shift outward or the patient vomits the tube, verify placement again or remove it if accidental extubation occurred.
Removal of the Nasogastric Tube
Removing a nasogastric tube is a straightforward procedure performed when the patient's gastrointestinal function returns or enteral support is no longer needed.
- Explain the procedure to the patient and place a towel across their chest.
- Disconnect the tube from suction or feeding equipment and unsecure it from the nose.
- Instruct the patient to take a deep breath and hold it (this closes the glottis and prevents accidental aspiration).
- Pinch or fold the tube to prevent leakage of residual fluid during withdrawal.
- Withdraw the tube smoothly and quickly with a single motion.
- Provide facial tissues and mouth care, then document the procedure, amount, and character of final drainage.