What is the optimal timing for endoscopy in cases of poisoning?

Optimal Timing of Endoscopy in Poisoning Cases

Endoscopy should be performed within 24 hours of presentation for most poisoning cases, with high-risk patients requiring urgent endoscopy within 12 hours of admission. 1

Risk Stratification for Timing of Endoscopy

The timing of endoscopy in poisoning cases depends on the type of poison, patient symptoms, and risk assessment:

For Gastrointestinal Bleeding Due to Poisoning:

• Very low-risk patients: May be suitable for outpatient management with delayed endoscopy 1
• Low-risk patients: Require hospital admission and endoscopy within 24 hours of presentation 1
• High-risk patients: Need immediate resuscitation and urgent endoscopy within 12 hours of admission 1

For Corrosive Substance Ingestion:

• Symptomatic patients: Early endoscopy (<12 hours after ingestion) is recommended to grade injury and determine if surgical intervention is needed 2
• Asymptomatic adults: May be discharged without endoscopy if clinical examination is normal and they can eat and drink normally 2
• Children with corrosive ingestion: More caution is needed; endoscopy is recommended for symptomatic children 3

Specific Timing Recommendations by Poison Type

Caustic/Corrosive Ingestions:

• Timing: Endoscopy should be performed within 12 hours after ingestion to assess mucosal damage 2
• Rationale: Mucosal injury begins within minutes following corrosive intake, and early endoscopy helps in assessing the degree of injury 4
• Caution: Delayed endoscopy (>24 hours) may increase risk of perforation during the procedure 4, 2

Variceal Bleeding (in cases of poisoning affecting liver):

• Timing: Endoscopy should be performed as soon as possible, ideally within 12 hours after presentation 1
• Evidence: A prospective observational study showed that early endoscopy (≤12 hours) was associated with lower 6-week rebleeding rate (18.9% vs. 38.9%) and mortality (27% vs. 52.8%) compared to delayed endoscopy 1

Non-variceal Upper GI Bleeding:

• Timing: Endoscopy within 24 hours of presentation for both low and high-risk patients 1
• High-risk patients: Consider more urgent endoscopy (within 12 hours), although evidence is limited 1
• Benefit: Early endoscopy allows for safe discharge of low-risk patients, potentially improves outcomes for high-risk patients, and reduces resource use 1

Special Considerations

Hemodynamic Stability:

• Patients should be hemodynamically stabilized before endoscopy, but this should not significantly delay the procedure 1
• For unstable patients, very early endoscopy (≤6 hours) may increase mortality risk, whereas endoscopy between 6-24 hours may reduce mortality compared to later timing 1

Coagulopathy:

• Coagulopathy should be assessed and treated as necessary, but endoscopy should not be delayed 1
• The degree of coagulopathy should be objectively assessed before therapeutic decisions are made 1

Resource Availability:

• Availability of endoscopy resources is an important consideration, especially during off-hours 1
• Patients hospitalized during off-hours are less likely to undergo endoscopy within 24 hours and may have higher mortality rates unless formal out-of-hours endoscopy services are available 1

Pitfalls and Caveats

• Delayed diagnosis: Postponing endoscopy beyond 24 hours may lead to missed opportunities for early intervention and increased morbidity 1
• Premature endoscopy: Performing endoscopy before adequate resuscitation in hemodynamically unstable patients may increase procedural risks 1
• Corrosive injuries: Endoscopy should not be delayed beyond 12-24 hours in corrosive ingestions as the risk of perforation increases with time 2
• Children with poisoning: Lower threshold for endoscopy is recommended as symptoms may not correlate with injury severity 3, 5

By following these timing recommendations for endoscopy in poisoning cases, clinicians can optimize patient outcomes by balancing the need for timely diagnosis and intervention with appropriate patient stabilization and resource utilization.