Nasogastric Tube Insertion: Indications and Procedure
Primary Indications
NGT insertion is indicated for gastric decompression in high-risk intubation scenarios, enteral nutrition when oral intake is inadequate with preserved gut function, and nutritional support in critically ill ventilated patients. 1
Specific Clinical Scenarios:
- Gastric decompression before rapid sequence intubation in patients with high aspiration risk, particularly when gastric fluid volume exceeds 1.5 mL/kg or solid gastric contents are present 1
- Short-term enteral nutrition (less than 4 weeks) for patients unable to meet caloric requirements over 5-7 days, or within 24-48 hours for severely malnourished patients 1
- Neurologic impairment including stroke with dysphagia, motor neuron disease, multiple sclerosis, or Parkinson's disease 1
- Head and neck pathology including cancer, maxillofacial trauma, or radiation stomatitis 1
- Unconscious or mechanically ventilated patients requiring nutritional support 1
Absolute Contraindications
Do not insert an NGT in the following situations:
- Mechanical GI obstruction (unless specifically for decompression purposes) 1
- Active peritonitis 1
- Uncorrectable coagulopathy 1
- Bowel ischemia 1
Relative Contraindications
Proceed with extreme caution or consider alternative routes:
- Abnormal nasal anatomy 1
- Recent facial trauma or oronasal surgery 1
- Recent GI bleeding from peptic ulcer with visible vessel or esophageal varices (delay 72 hours) 1
- Hemodynamic instability 1
- Severe respiratory compromise 1
Pre-Insertion Assessment
Laboratory Testing:
- Check INR for all patients before insertion 1
- Measure activated PTT only in patients receiving IV unfractionated heparin 1
- Platelet count and hematocrit are not routinely required 1
Clinical Assessment:
- Use point-of-care ultrasound to assess gastric distention or full stomach status 1
- Explain the procedure and obtain consent 1
Insertion Technique
Equipment Selection:
Select an 8-12 French tube for adults; use 8 French specifically in stroke patients to minimize pressure sores. 1
Step-by-Step Procedure:
- Position the patient with head flexed forward during insertion 1
- Lubricate the tube thoroughly before insertion 1
- Insert through the nostril with the patient taking sips of water to assist passage 1
- Advance the tube to appropriate depth - note that the commonly used nose-earlobe-xiphoid method is too short and newer, safer measurement methods should be used 2
Difficult Insertion Strategies:
- Apply generous lubrication 3
- Consider chilling the tube 3
- Use two fingers in the mouth to guide passage 3
- Employ direct visualization if needed 3
- For complex cases, use image-guided placement with fluoroscopy or ultrasound 1
- Consider endoscopic guidance in particularly difficult situations 1
Position Verification - CRITICAL SAFETY STEP
Radiographic confirmation is mandatory before initiating any feeding or medication administration. 1
Why This Matters:
- Bedside auscultation is unreliable and dangerous with only 79% sensitivity and 61% specificity 1
- Tubes can enter the lung, pleural cavity, or coil in the esophagus if position is not radiographically confirmed, which can be life-threatening 1
- Every patient must undergo radiography to confirm proper gastric position 1
Alternative Verification Methods (Not for Initial Placement):
- Aspiration of gastric contents with pH measurement (aspirate should be pH <5.5) for subsequent position checks 1
Post-Insertion Management
Immediate Care:
- Secure the tube properly - dislodgement occurs in 40-80% of NGT tubes without proper securement 1
- Consider nasal bridles for high-risk patients (reduces dislodgement from 36% to 10% compared to adhesive tape) 1
- For patients at high risk of skin breakdown, use low-adherent film as a contact layer with tape securing to the film rather than directly to skin 1
Ongoing Maintenance:
- Flush the tube with 40 mL of water after each medication administration or feeding 1
- Change dressing regularly and inspect insertion site for irritation 1
- Monitor for signs of infection at the insertion site 1
Feeding Initiation:
- Begin feeding immediately after radiographic confirmation of proper placement 1
- Start at full-strength formula without dilution in patients with recent adequate nutritional intake 1
- Use 30 mL/kg/day of standard 1 kcal/mL feed as a reasonable starting point 1
- Position patient at 30° or greater during feeding and maintain for 30 minutes after bolus feeds 1
Major Complications and Prevention
Life-Threatening Complications:
- Aspiration pneumonia - especially in patients with impaired swallowing (40-78% of stroke patients have dysphagia) 1
- Airway compromise from nasal bleeding with blood clot aspiration in patients unable to protect their airway 4
- Intracranial placement in patients with severe facial or skull injuries 3
- Esophageal perforation 3
Common Complications:
- Dislodgement (40-80% without proper securement) 1
- Tube occlusion requiring replacement 1
- Sinusitis with prolonged use beyond 3-4 weeks 1
- Nasal mucosal bleeding 4
Special Considerations
Duration of Use:
NGT is appropriate for short-term use (less than 4 weeks); consider percutaneous endoscopic gastrostomy (PEG) for longer-term needs. 1
- In mechanically ventilated stroke patients requiring prolonged nutrition (>14 days), early PEG within 1 week is preferred over NGT due to lower rates of ventilator-associated pneumonia 1
Stroke Patients:
- NGT does not necessarily impair swallowing therapy, which should start as early as possible 1
- Early NGT feeding may substantially decrease risk of death compared to delayed feeding 1
- Assess for dysphagia before oral intake 1
Patient Education Before Discharge:
Patients and caregivers must demonstrate competency in: