ColonoscopyNot the cure for Acute Lower GI Bleeding

Liz O’GormanSurgical InternCork University Hospital

• Acute – within 24 hours

• LGIB in Irish Healthcare System- Diverticular Bleed- Angiodysplasia

- IBD/Colitis- Neoplasia- Rectal Trauma- Iatrogenic

Aim of Colonoscopy is to diagnose and treat bleeding sources

I will discuss:

1. Limitations of colonoscopy

2. Risks of colonoscopy

3. Better alternative options

Why not perform Colonoscopy?

• Long standing debate

• Numerous studies tried to address this question

• No gold standard test for acute LGIB

AIM = treat and diagnose bleeding source

• 1 – need to identify source

• 2 – facilities to implement treatment

Limitations of Colonoscopy

1. Bowel Preparation

• Unique to endoscopic interventions

• Cleansing bowel of stool and blood imperative to diagnosis

• Unprepped- caecum in 55-70% Chaudry at al- reduced identification of bleeding sites Tada et al- increased risk of perforation Strate et al

• Diverticular bleeds- multiple subtle bleeding sites- active bleeding identified 21% Jensen et al, 2000- aggressive bowel prep

• Green at al, 2005- 62-64% endoscopic view rated poor to fair

2. Stigmata of Haemorrhage• Diagnostic interventions alone do not alter rebleeding and operative rates

• Variable reports of identification- 7.7% – 43 % Angtuaco et al, 2001; Schmuelewitz et al, 2003

• Bleeding intermittent- difficult to differentiate fresh blood from old blood and stool

• 20% haematochezia secondary to Upper GI bleed - Jensen et al, 1998; Laine et al 2010

3. Your Environment• Not all centres have same access to on call colonoscopy

• Trained personel- trained nursing staff- endoscopy suite / OT- anaesthetist if pt unstable

• Waiting for prep – increases likelihood of out of hours colonoscopy

• Strate et al, 2003- median time from admission to colonoscopy 17hours for LGIB

managed with urgent colonoscopy

Risks

1. Perforation

• Low: 0.3-1.3%

• Catastrophic with high mortality– patient already compromised

2. Volume Shifts

• Rapid bowel preps

• Haemodynamically compromised patients

• Renal compromise and electrolyte imbalances Goldman et al,1982

• Left ventricular dysfunction- exacerbation of symptoms and ECF volume overload

Alternatives

Angiography

• Diagnostic and therapeutic• Superselective embolisation

• Meta-analysis J GI Surg 2005 Khanna A et al- Diverticular Bleed 85% success

*if fails < 2 days- Non-diverticular Bleed 50% success

* if fails < 2 days

CT Angiography

• Triage prior to angiography (avoid risks associated with intervention)

• ALL patients with a suspected, known or previously treated AAA- ? Aortoenteric fistula

• Bleeding of 2cc/sec

Radionucleotide Scintigraphy

• Radiolabelled RBCs (99mTc)

• Identifies LGIB site in up to 78% of cases

• Bleeding of 0.2 cc/sec

• No intervention risks

Summary• Colonoscopy

- difficult to reach caecum without aggressive bowel prep- difficult to identify bleeding source even with bowel prep- prep associated electrolyte disturbances and volume shifts- risk of perforation- median time from admission 17hours ? acute

• Alternatives- CT / CT Angio / Radionucleotide Scans

BOTTOM LINE

•Colonoscopy diagnostically poor in acute LGIB

• You can not treat something you can not diagnose

•Acute lower GI bleeding usually stops without intervention

Thank You