What is the Forrest classification of bleeding peptic ulcers?

Forrest Classification of Bleeding Peptic Ulcers

The Forrest classification is an endoscopic scoring system that categorizes bleeding peptic ulcers based on their appearance and predicts the risk of rebleeding, need for intervention, and mortality. 1

Classification Categories

• Forrest I: Active bleeding

  • Forrest Ia: Spurting arterial bleeding (highest risk of rebleeding) 1, 2
  • Forrest Ib: Oozing bleeding (lower risk of rebleeding compared to IIa and IIb) 1, 2

• Forrest II: Signs of recent bleeding

  • Forrest IIa: Non-bleeding visible vessel 1, 2
  • Forrest IIb: Adherent clot 1
  • Forrest IIc: Flat pigmented spot/hematin on ulcer base 2

• Forrest III: Clean ulcer base with no signs of bleeding (lowest risk) 3, 2

Clinical Significance and Risk Stratification

• High Risk: Forrest Ia (spurting) has the highest rebleeding rate at approximately 59% 2
• Increased Risk: Forrest Ib-IIc have similar odds ratios for rebleeding 2
• Low Risk: Forrest III ulcers rarely rebleed and may not require hospitalization 3

Management Implications

• Forrest Ia, Ib, and IIa: Endoscopic hemostasis is strongly recommended 1
• Forrest IIb (adherent clot):
  • WSES advocates non-aggressive clot irrigation rather than mechanical dislodgment 1
  • Asia-Pacific Working Group recommends vigorous target irrigation for at least 5 minutes 1
  • Individual endoscopist judgment is important based on expertise 1
• Forrest IIc and III: Lower risk of rebleeding, may not require endoscopic intervention 2

Treatment Considerations

• Dual modality endoscopic hemostasis is preferred over single modality for high-risk lesions 1

  • Mechanical therapy combined with epinephrine injection significantly reduces rebleeding (OR 0.19,95% CI 0.07-0.52) and need for surgery (OR 0.10,95% CI 0.01-0.50) 1
  • Epinephrine with thermal therapy reduces rebleeding (OR 0.30,95% CI 0.10-0.91) 1

• Doppler probe assessment can improve risk stratification beyond the Forrest classification 1

  • Forrest Ia, IIa, and IIb lesions have higher Doppler flow compared to Forrest Ib 1

Important Clinical Considerations

• The Forrest classification is more reliable for predicting rebleeding in gastric ulcers than duodenal ulcers 2
• While useful for predicting rebleeding risk, the classification has limited value in predicting mortality 2
• Some experts have proposed simplifying the classification into three risk categories: high risk (Ia), increased risk (Ib-IIc), and low risk (III) 2
• Endoscopy should be performed as early as possible to properly classify and plan treatment 4

Post-Endoscopic Management

• After successful endoscopic hemostasis, high-dose PPI as continuous infusion for the first 72 hours is recommended 1
• PPI therapy should be continued for 6-8 weeks following endoscopic treatment 1