When is intranasal ketamine appropriate for sedation, and what are the recommended dosing and monitoring guidelines?

Intranasal Ketamine for Procedural Sedation in Children

Intranasal ketamine is safe and effective for procedural sedation in pediatric patients, particularly for brief painful procedures like laceration repair, with recommended dosing of 4-7 mg/kg, though it has a slightly lower success rate (60-85%) compared to IV ketamine. 1, 2, 3, 4

Appropriate Clinical Indications

Intranasal (IN) ketamine is most appropriate for:

• Brief painful procedures requiring sedation and analgesia (laceration repair, minor wound care, fracture reduction) 2
• Pediatric patients aged 1-12 years who would benefit from needle-free sedation 3, 4, 5
• Severely needle-phobic children where IV access would cause significant distress 6
• Situations requiring anxiolysis and analgesia without the resource intensity of full procedural sedation 5

The 2004 ACEP guidelines provide Level A evidence that ketamine can be safely administered to children for procedural sedation and analgesia in the ED 1, 2. This applies primarily to IV/IM routes, but the dissociative properties and safety profile extend to the intranasal route 7.

Recommended Dosing

The optimal initial dose is 6 mg/kg intranasally, with an effective range of 4-7 mg/kg 3, 4, 5:

• Lower doses (3-5 mg/kg) maximize patient comfort but may have reduced efficacy 5
• 6 mg/kg achieved effective sedation in 60% of patients, with an additional 17% having suboptimal but adequate sedation 4
• Onset of sedation: 4-5 minutes on average 2
• Duration: Typically sufficient for brief procedures (15-30 minutes of effect) 8, 9

A moderate correlation exists between dose and onset time—higher doses produce faster sedation 3. The dose also correlates moderately with patient age, suggesting individualization within the 4-7 mg/kg range based on age and procedure complexity 3.

Efficacy Considerations

Success rates for IN ketamine range from 60-85%, which is lower than IV ketamine (approaching 100%) 2, 6, 4, 10:

• In the multicenter trial by Tsze et al., 18/30 (60%) achieved effective sedation, 5/30 (17%) had suboptimal but adequate sedation, and 7/30 (23%) had poor sedation with 3/30 (10%) requiring additional agents 4
• A systematic review found 148/175 (85%) of participants achieved adequate sedation across studies 10
• Treatment failure rate: approximately 8-10% require rescue with additional sedatives 4, 5

The lower success rate compared to IV ketamine must be weighed against the benefits of avoiding IV placement, particularly in needle-phobic children. Shared decision-making with parents is essential, explaining that IN ketamine offers a less invasive alternative with slightly reduced efficacy 6.

Safety Profile and Adverse Events

IN ketamine has an excellent safety profile with only minor adverse events reported 1, 2, 3, 4, 5, 10:

Common Minor Adverse Events:

• Nausea/vomiting: 7-10% (most common) 2, 5, 10
• Dizziness: 1% 5
• Drowsiness: 1% 5
• Recovery agitation: 6-7% 2

Serious Adverse Events:

• No serious adverse events were reported in pediatric IN ketamine studies 11, 8, 4, 5, 10
• No respiratory support or intubation required in any reviewed studies 5
• Laryngospasm risk: Rare but possible; occurs more with rapid IV administration 7, 12

The 2004 ACEP guidelines note that ketamine (IV/IM) has hypoxemia rates of only 1.6-7.3%, significantly lower than fentanyl/midazolam combinations (24%) 2. Ketamine maintains airway reflexes and spontaneous ventilation, distinguishing it from other sedatives 11, 8, 7.

Monitoring Requirements

Standard procedural sedation monitoring is required 1, 2, 7, 9:

• Continuous pulse oximetry and capnography (when available)
• Vital signs every 5-10 minutes during sedation
• Dedicated personnel for monitoring separate from the proceduralist
• Recovery monitoring until patient returns to baseline (typically 60-90 minutes total) 2
• Resuscitation equipment immediately available including oxygen, suction, bag-valve-mask, and airway adjuncts 1, 2, 9

The 2019 multidisciplinary consensus guideline emphasizes that dissociative sedation with ketamine maintains airway reflexes and effective spontaneous ventilation, though transient respiratory depression can occur 1-2 minutes after rapid IV administration 7. This is less relevant for IN administration due to slower absorption.

Contraindications and Precautions

Avoid IN ketamine in patients with 11, 8, 9:

• Ischemic heart disease, uncontrolled hypertension, or cerebrovascular disease (ketamine increases heart rate, blood pressure, and cardiac output via sympathetic stimulation) 11, 8
• Hepatic or renal insufficiency (ketamine is metabolized by liver, excreted by kidneys) 13
• Increased intracranial pressure concerns (though evidence is mixed)
• Age <1 year (limited safety data) 4

Emergence Reactions:

• 10-30% of adults experience emergence phenomena (hallucinations, agitation, vivid dreams) 11, 8
• Much less common in children 2
• Coadministration of midazolam (0.05-0.1 mg/kg) can reduce emergence reactions but may increase recovery agitation in children >10 years 2
• Minimize stimulation during recovery (sound, handling) to reduce emergence reactions 13

Practical Advantages Over IV Sedation

IN ketamine offers significant operational benefits 5:

• Reduced ED length of stay: 238 minutes vs. 332 minutes for IV procedural sedation (p<0.001) 5
• No IV access required: Eliminates needle stick distress and time for IV placement
• Less resource-intensive: Frees up staff and monitoring equipment 5
• High provider satisfaction: 100% of providers comfortable using it, median satisfaction 90/100 5
• High parental satisfaction: Median 88-92% rated as "excellent or good" 2

Key Clinical Pitfalls to Avoid

1. Underdosing: Using <4 mg/kg significantly reduces efficacy 3, 4
2. Inadequate monitoring: Despite maintained airway reflexes, standard sedation monitoring is mandatory 1, 2, 7
3. Failure to have rescue plan: 8-10% may require additional sedation; have IV access capability and alternative agents ready 4, 5
4. Stimulation during recovery: Increases emergence reactions; maintain quiet environment 13
5. Using in patients with cardiovascular contraindications: Sympathetic stimulation can be dangerous in specific populations 11, 8
6. Expecting 100% success rate: IN ketamine has 60-85% efficacy vs. near 100% for IV; set appropriate expectations with families 6, 4

Algorithm for Use

Step 1: Identify appropriate candidate

• Age 1-12 years
• Brief painful procedure (<30 minutes)
• No cardiovascular/hepatic/renal contraindications
• Needle-phobic or preference for non-IV approach

Step 2: Obtain informed consent

• Explain 60-85% success rate
• Discuss 8-10% may need additional sedation
• Review minor adverse events (nausea 7-10%)

Step 3: Prepare and monitor

• Standard procedural sedation setup
• Resuscitation equipment available
• Dedicated monitoring personnel

Step 4: Administer IN ketamine

• Dose: 6 mg/kg (range 4-7 mg/kg based on age/procedure)
• Onset: 4-5 minutes
• Minimize stimulation during induction

Step 5: Assess sedation adequacy at 5-10 minutes

• Adequate: Proceed with procedure
• Suboptimal but tolerable: Proceed with gentle approach
• Inadequate: Consider rescue with additional IN ketamine (1 mg/kg) or transition to IV sedation 2

Step 6: Recovery monitoring

• Quiet environment
• Monitor until baseline mental status
• Typical total time: 60-90 minutes 2