Gastrointestinal hemorrhage
Gastrointestinal hemorrhage (GI bleeding) is defined as "bleeding in any segment of the gastrointestinal tract from esophagus to rectum."[1] Template:TOC-right
Diagnosis
Upper gastrointestinal tract bleeding
Summary
The diagnosis of upper GI bleeding is assumed when hematemesis is documented. In the absence of hematemesis, an upper source for GI bleeding is likely in the presence of at least two factors among: black stool, age < 50 years, and blood urea nitrogen/creatinine ratio 30 or more.[2] In the absence of these findings, consider a nasogastric aspirate to determine the source of bleeding. If the aspirate is positive, an upper GI bleed is greater than 50%, but not high enough to be certain. If the aspirate is negative, the source of a GI bleed is likely lower. The accuracy of the aspirate is improved by using the Gastroccult test.[3]
Clinical predictors
Two clinical prediction rules, the Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Glasgow-Blatchford bleeding score and the Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Rockall score, can help identify patients at risk of complications.[4] A cohort of 325 patients reported that the odds ratios for the strongest predictors were: black stool, 16.6, age < 50 years, 8.4, and blood urea nitrogen/creatinine ratio 30 or more, 10.0.[2] Seven (5%) of 151 with none of these factors had an upper GI tract bleed, versus 63 (93%) of 68 with 2 or 3 factors. Ernst found similar results.[3]
Nasogastric aspirate
The nasogastric aspirate can help determine the location of bleeding and thus direct initial diagnostic and treatment plans. Witting found that nasogastric aspirate has sensitivity 42%, specificity 91%, negative predictive value 64%, positive predictive value 92% and overall accuracy of 66% in differentiating upper GI bleeding from bleeding distal to the ligament of Treitz.[5] Thus, in this study a positive aspirate is more helpful than a negative aspirate. In a smaller study, Cuellar found a sensitivity of 79% and specificity of 55%[6], somewhat opposite results from Witting. Cuellar also studied the appearance of the aspirate and the results are in the table.
| Finding | Sensitivity | Specificity | Positive predictive value (prevalence of 39%) |
Negative predictive value (prevalence of 39%) |
|---|---|---|---|---|
| Gastroccult | 95% | 82% | 77% | 96% |
| Physician assessment | 79% | 55% | 53% | 20% |
Determining whether blood is in gastric contents, either vomited or aspirated specimens, is surprisingly difficult. Slide tests are based on orthotolidine (Hematest reagent tablets and Bili-Labstix) or guaiac (Hemoccult and Gastroccult). Rosenthal found orthotolidine-based tests more sensitive than specific; the Hemoccult test's sensitivity reduced by the acidic environment; and the Gastroccult test be the most accurate.[7]
Holman used simulated gastric specimens and found the Hemoccult test to have significant problems with non-specificy and false-positive results, whereas the Gastroccult test was very accurate.[8] Holman found that by 120 seconds after the developer was applied, the Hemoccult test was positive on all control samples.[8]
Esophagogastroduodenoscopy
Esophagogastroduodenoscopy (EGD) can help determine the cause of the bleeding. Intravenous erythromycin prior to endoscopy can help clear the stomach of blood to improve the exam.[9]
Lower gastrointestinal tract bleeding
Prognosis
Upper gastrointestinal tract bleeding
For patients with nonvariceal upper gastrointestinal tract bleeding, the Blatchford score is a clinical prediction rule for predicting patients that will require blood transfusion, endoscopic or surgical management for bleeding control.[10]
The score is high risk if the patient has any of the following:
- Blood urea nitrogen ≥18.2 (mg/dL)
- Hemoglobin level
- for men <13 (g/dL)
- for women <12 (g/dL)
- Systolic blood pressure <109(mm Hg)
- Pulse rate ≥100 beats/min
- Melena
- Syncope
- Hepatic disease
- Heart failure
In a study in which 69.5% of the patients were had blood transfusion, endoscopic or surgical management, the accuracy fo the score is:
- sensitivity = 99.6%
- specificity = 25.0%
which yielded:
- positive predictive value = 75.2%
- negative predictive value = 96.4%
Lower gastrointestinal tract bleeding
References
- ↑ National Library of Medicine. Gastrointestinal Hemorrhage. Retrieved on 2007-11-09.
- ↑ 2.0 2.1 Witting MD, Magder L, Heins AE, Mattu A, Granja CA, Baumgarten M (2006). "ED predictors of upper gastrointestinal tract bleeding in patients without hematemesis". Am J Emerg Med 24 (3): 280–5. DOI:10.1016/j.ajem.2005.11.005. PMID 16635697. Research Blogging.
- ↑ 3.0 3.1 Ernst AA, Haynes ML, Nick TG, Weiss SJ (1999). "Usefulness of the blood urea nitrogen/creatinine ratio in gastrointestinal bleeding". Am J Emerg Med 17 (1): 70–2. PMID 9928705. [e]
- ↑ Stanley A, Ashley D, Dalton H, et al (December 2008). "Outpatient management of patients with low-risk upper-gastrointestinal haemorrhage: multicentre validation and prospective evaluation". Lancet. DOI:10.1016/S0140-6736(08)61769-9. PMID 19091393. Research Blogging.
- ↑ Witting MD, Magder L, Heins AE, Mattu A, Granja CA, Baumgarten M (2004). "Usefulness and validity of diagnostic nasogastric aspiration in patients without hematemesis". Ann Emerg Med 43 (4): 525–32. DOI:10.1016/S0196064403009417. PMID 15039700. Research Blogging.
- ↑ 6.0 6.1 Cuellar RE, Gavaler JS, Alexander JA, et al (1990). "Gastrointestinal tract hemorrhage. The value of a nasogastric aspirate". Arch. Intern. Med. 150 (7): 1381–4. PMID 2196022. [e]
summary of these results is available at the Evidence-Based On-Call database and through the Wayback Archive Cite error: Invalid
<ref>tag; name "pmid2196022" defined multiple times with different content - ↑ Rosenthal P, Thompson J, Singh M (1984). "Detection of occult blood in gastric juice". J. Clin. Gastroenterol. 6 (2): 119–21. PMID 6715849. [e]
- ↑ 8.0 8.1 Holman JS, Shwed JA (1992). "Influence of sucralfate on the detection of occult blood in simulated gastric fluid by two screening tests". Clin Pharm 11 (7): 625–7. PMID 1617913. [e]
- ↑ Winstead NS, Wilcox CM (2007). "Erythromycin prior to endoscopy for acute upper gastrointestinal haemorrhage: a cost-effectiveness analysis". Aliment. Pharmacol. Ther. 26 (10): 1371–7. DOI:10.1111/j.1365-2036.2007.03516.x. PMID 17848180. Research Blogging.
- ↑ Chen IC, Hung MS, Chiu TF, Chen JC, Hsiao CT (2007). "Risk scoring systems to predict need for clinical intervention for patients with nonvariceal upper gastrointestinal tract bleeding". The American journal of emergency medicine 25 (7): 774–9. DOI:10.1016/j.ajem.2006.12.024. PMID 17870480. Research Blogging.