Management of colonic diverticular bleeding: A narrative review with literature search of current evidence and therapeutic strategies

Table 3 Transfusion strategy: Evidence base and guideline recommendations

Domain	Study/threshold	Key finding/recommendation
Hb threshold	7 g/dL (restrictive)	Standard recommendation for hemodynamically stable LGIB
	8 g/dL	Reasonable in significant cardiovascular disease
	Before Hb < 7 if hypotensive	Dilutional drop post-resuscitation underestimates deficit; transfuse early
UGIB RCT evidence	Villanueva et al[21] (n = 921)	Restrictive: Improved 6-week survival, lower rebleeding vs liberal
	Meta-analysis 5 RCTs (n = 1965)	Restrictive: RR mortality 0.65 (0.44-0.97); Rebleeding RR 0.58 (0.40-0.84)
	Teutsch et al[24] meta-analysis (7 RCTs)	Restrictive did not increase in-hospital or 30-day mortality
LGIB data	United Kingdom audit post hoc analysis	No significant difference in rebleeding or mortality between strategies; post hoc, underpowered
Guidelines	AABB 2023 International Guidelines[27]	Restrictive strategy recommended across clinical settings
	ACG, ESGE, BSG	Hb 7 g/dL stable patients; 8 g/dL in CVD; early transfusion if hemodynamically unstable

Evidence for lower gastrointestinal bleeding is largely extrapolated from upper gastrointestinal bleeding trials; dedicated lower gastrointestinal bleeding transfusion randomized controlled trials are needed. Hb: Hemoglobin; UGIB: Upper gastrointestinal bleeding; RCT: Randomized controlled trial; LGIB: Lower gastrointestinal bleeding; AABB: American Association of Blood Banks; ACG: American College of Gastroenterology; ESGE: European Society of Gastrointestinal Endoscopy; BSG: British Society of Gastroenterology; CVD: Cardiovascular disease; RR: Relative risk.