Can lidocaine gel be used for nasogastric tube insertion?

Lidocaine Gel for Nasogastric Tube Insertion

Yes, lidocaine gel should be used for nasogastric tube insertion as it significantly reduces pain and discomfort associated with the procedure. Multiple high-quality studies demonstrate clinically meaningful pain reduction without increasing complications.

Evidence for Efficacy

The evidence strongly supports lidocaine use for NG tube insertion:

• A 2018 meta-analysis of 10 randomized controlled trials (734 patients) demonstrated that lidocaine application before NG tube insertion reduced pain scores by 26% on the visual analog scale (VAS), with a mean difference of -26.05 (95% CI: -28.21 to -23.89, p < 0.001) 1.

• Individual trials consistently show benefit: lidocaine gel reduced overall pain from 51 mm to 37 mm on a 100-mm VAS (p < 0.05), nasal pain from 48 mm to 33 mm (p < 0.05), and gagging sensation from 39 mm to 25 mm (p < 0.05) 2.

• Atomized 4% lidocaine combined with 2% lidocaine jelly reduced pain scores from 64.5 mm to 37.4 mm (mean difference 27.1 mm, 95% CI: 14.8-39.4), achieving both clinical and statistical significance 3.

Recommended Application Protocol

Apply 2% lidocaine gel intranasally 5 minutes before NG tube insertion 2, 4:

• Use 5 mL of 2% lidocaine gel as the standard dose 2, 4.
• For enhanced analgesia, consider combining with 10% lidocaine spray to the nostril and throat prior to gel application, which further reduces pain (23.6 mm vs 43.1 mm VAS, p = 0.005) and discomfort (30.0 mm vs 51.4 mm, p = 0.004) 5.
• Alternatively, atomized 4% lidocaine (1.5 mL) to the nasopharynx and oropharynx followed by 2% lidocaine jelly intranasally provides excellent pain control 3.

Safety Considerations

Lidocaine gel for NG tube insertion has an excellent safety profile with no increased risk of complications 1:

• No significant increase in nasal bleeding (OR = 0.62,95% CI: 0.11-3.41, p = 0.59) 1.
• No increase in vomiting (OR = 0.30,95% CI: 0.07-1.27, p = 0.10) 1.
• The dose used (typically 100 mg in 5 mL of 2% gel) is well below toxic thresholds 2, 4.

For adults, ensure topical lidocaine dose does not exceed 9 mg/kg lean body weight 6. This maximum is rarely required in practice for NG tube insertion 6.

For pediatric patients, use more conservative dosing 7:

• Maximum 5 mg/kg ideal body weight for procedures up to 2 hours 7.
• Maximum 4 mg/kg ideal body weight for children < 6 months, those who are underweight, or have hepatic disease 7.
• Use 1% or 2% lidocaine solutions in children weighing < 10 kg 7.
• Avoid lidocaine solutions > 4% concentration in children 7.

Important Caveats

One practical consideration: lidocaine gel may make tube insertion slightly more difficult 2:

• Physicians rated insertion difficulty higher with lidocaine (2.1 ± 0.9 vs 1.4 ± 0.7 on 5-point Likert scale, p < 0.05) 2.
• However, this did not affect success rates, number of attempts, or duration of intubation 2, 1, 5.
• The increased difficulty is offset by significantly improved patient comfort and satisfaction 2, 5.

Avoid lidocaine solutions containing vasoconstrictors (e.g., adrenaline/epinephrine) for airway topicalization in children due to risk of hypertensive crises and cardiac arrest 7.

Patient and Provider Satisfaction

Both patients and providers prefer lidocaine use 5:

• 93% of patients receiving lidocaine spray plus gel favored the same approach for future intubations, compared to 65% in the placebo group (p = 0.009) 5.
• Physician satisfaction was significantly higher with lidocaine use (p = 0.041) 5.