Snapshot A 40-year-old man presents to the emergency room soon after arriving back from a vacation on a cruise ship. He reports feeling unwell and losing his appetite in the past few days. He has had several episodes of nausea and vomiting, but today had an episode of bloody diarrhea. He is otherwise healthy and is concerned about the amount of blood. He has also had subjective fevers. (Infectious colitis) Introduction Overview lower gastrointestinal bleed results from bleeding from the colon or rectum Epidemiology incidence very common epidemiology elderly patients with comorbid conditions risk factors diverticulosis angiodysplasia ischemic colitis neoplasm inflammatory bowel disease infection Salmonella Shigella hemorrhoids anal fissure Pathogenesis mechanism depends on the etiology Prognosis can be inconsequential or life-threatening Presentation Symptoms common symptoms rectal bleeding hematochezia bright red (originating from left side of colon) maroon blood (originating from right side of colon) has the potential to be fatal and cause massive hemorrhagic shock fecal occult blood test is positive a fever may indicate infectious etiology painless bleeding may indicate angiodysplasia or diverticular bleeding abdominal pain may indicate ischemic colitis Physical exam inspection dehydration Imaging Radionuclide scan indications often performed before angiography as it is not invasive and a negative result negates a need for further invasive procedures high sensitivity Angiography indications hemodynamically unstable patients if colonoscopy does not reveal a bleeding site in hemodynamically stable patients can also be therapeutic Studies Serum labs complete blood count serum electrolytes coagulation studies Invasive studies colonoscopy/anoscopy/sigmoidoscopy indication first-line for patients who are hemodynamically stable patients require bowel preparation can also be used therapeutically for hemostasis in patients > 40 years of age, must rule out malignancy with colonoscopy Differential Upper gastrointestinal bleed key distinguishing factor source of bleeding from stomach or small intestine may also present as bright red blood if there is rapid hemorrhage Treatment Medical resuscitation modalities large-bore intravenous access crystalloid fluid replacement blood transfusions if needed Surgical colonoscopy/anoscopy/sigmoidoscopy indication both diagnostic and therapeutic colonoscopy specifically for all patients over 40 to rule out malignancy modalities hemostasis via coagulation i.e., electrocoagulation clip placement angiography indication both diagnostic and therapeutic used when colonoscopy is unrevealing or contraindicated hemodynamically unstable patients modalities embolization vasopressin drip surgical exploration indication hemodynamically unstable patients refractory to resuscitation persistent or recurrent bleeding Complications Death Shock
QUESTIONS 1 of 4 1 2 3 4 Previous Next Lab Values Blood Hematologic Cerebrospinal Sweat, Urine, and BMI Blood, Plasma, Serum Reference Range ALT 8-20 U/L Amylase, serum 25-125 U/L AST 8-20 U/L Bilirubin, serum (adult) Total // Direct 0.1-1.0 mg/dL // 0.0-0.3 mg/dL Calcium, serum (Ca2+) 8.4-10.2 mg/dL Cholesterol, serum Rec: < 200 mg/dL Cortisol, serum 0800 h: 5-23 μg/dL //1600 h: 3-15 μg/dL 2000 h: ≤ 50% of 0800 h Creatine kinase, serum Male: 25-90 U/LFemale: 10-70 U/L Creatinine, serum 0.6-1.2 mg/dL Electrolytes, serum Sodium (Na+) 136-145 mEq/L Chloride (Cl-) 95-105 mEq/L Potassium (K+) 3.5-5.0 mEq/L Bicarbonate (HCO3-) 22-28 mEq/L Magnesium (Mg2+) 1.5-2.0 mEq/L Estriol, total, serum (in pregnancy) 24-28 wks // 32-36 wks 30-170 ng/mL // 60-280 ng/mL 28-32 wk // 36-40 wks 40-220 ng/mL // 80-350 ng/mL Ferritin, serum Male: 15-200 ng/mLFemale: 12-150 ng/mL Follicle-stimulating hormone, serum/plasma Male: 4-25 mIU/mL Female: premenopause: 4-30 mIU/mL midcycle peak: 10-90 mIU/mL postmenopause: 40-250 pH 7.35-7.45 PCO2 33-45 mmHg PO2 75-105 mmHg Glucose, serum Fasting: 70-110 mg/dL2-h postprandial:<120 mg/dL Growth hormone - arginine stimulation Fasting: <5 ng/mLProvocative stimuli: > 7ng/mL Immunoglobulins, serum IgA 76-390 mg/dL IgE 0-380 IU/mL IgG 650-1500 mg/dL IgM 40-345 mg/dL Iron 50-170 μg/dL Lactate dehydrogenase, serum 45-90 U/L Luteinizing hormone, serum/plasma Male: 6-23 mIU/mL Female: follicular phase: 5-30 mIU/mL midcycle: 75-150 mIU/mL postmenopause 30-200 mIU/mL Osmolality, serum 275-295 mOsmol/kd H2O Parathyroid hormone, serume, N-terminal 230-630 pg/mL Phosphatase (alkaline), serum (p-NPP at 30° C) 20-70 U/L Phosphorus (inorganic), serum 3.0-4.5 mg/dL Prolactin, serum (hPRL) < 20 ng/mL Proteins, serum Total (recumbent) 6.0-7.8 g/dL Albumin 3.5-5.5 g/dL Globulin 2.3-3.5 g/dL Thyroid-stimulating hormone, serum or plasma .5-5.0 μU/mL Thyroidal iodine (123I) uptake 8%-30% of administered dose/24h Thyroxine (T4), serum 5-12 μg/dL Triglycerides, serum 35-160 mg/dL Triiodothyronine (T3), serum (RIA) 115-190 ng/dL Triiodothyronine (T3) resin uptake 25%-35% Urea nitrogen, serum 7-18 mg/dL Uric acid, serum 3.0-8.2 mg/dL Hematologic Reference Range Bleeding time 2-7 minutes Erythrocyte count Male: 4.3-5.9 million/mm3Female: 3.5-5.5 million mm3 Erythrocyte sedimentation rate (Westergren) Male: 0-15 mm/hFemale: 0-20 mm/h Hematocrit Male: 41%-53%Female: 36%-46% Hemoglobin A1c ≤ 6 % Hemoglobin, blood Male: 13.5-17.5 g/dLFemale: 12.0-16.0 g/dL Hemoglobin, plasma 1-4 mg/dL Leukocyte count and differential Leukocyte count 4,500-11,000/mm3 Segmented neutrophils 54%-62% Bands 3%-5% Eosinophils 1%-3% Basophils 0%-0.75% Lymphocytes 25%-33% Monocytes 3%-7% Mean corpuscular hemoglobin 25.4-34.6 pg/cell Mean corpuscular hemoglobin concentration 31%-36% Hb/cell Mean corpuscular volume 80-100 μm3 Partial thromboplastin time (activated) 25-40 seconds Platelet count 150,000-400,000/mm3 Prothrombin time 11-15 seconds Reticulocyte count 0.5%-1.5% of red cells Thrombin time < 2 seconds deviation from control Volume Plasma Male: 25-43 mL/kgFemale: 28-45 mL/kg Red cell Male: 20-36 mL/kgFemale: 19-31 mL/kg Cerebrospinal Fluid Reference Range Cell count 0-5/mm3 Chloride 118-132 mEq/L Gamma globulin 3%-12% total proteins Glucose 40-70 mg/dL Pressure 70-180 mm H2O Proteins, total < 40 mg/dL Sweat Reference Range Chloride 0-35 mmol/L Urine Calcium 100-300 mg/24 h Chloride Varies with intake Creatinine clearance Male: 97-137 mL/minFemale: 88-128 mL/min Estriol, total (in pregnancy) 30 wks 6-18 mg/24 h 35 wks 9-28 mg/24 h 40 wks 13-42 mg/24 h 17-Hydroxycorticosteroids Male: 3.0-10.0 mg/24 hFemale: 2.0-8.0 mg/24 h 17-Ketosteroids, total Male: 8-20 mg/24 hFemale: 6-15 mg/24 h Osmolality 50-1400 mOsmol/kg H2O Oxalate 8-40 μg/mL Potassium Varies with diet Proteins, total < 150 mg/24 h Sodium Varies with diet Uric acid Varies with diet Body Mass Index (BMI) Adult: 19-25 kg/m2 Calculator ( ) xy AC 7 8 9 ÷ 4 5 6 × 1 2 3 - 0 . = + Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK You have 100% on this question. Just skip this one for now. Take This Question Anyway (M3.GI.2) A 71-year-old woman is brought to the emergency department following a syncopal episode. Earlier in the day, the patient had multiple bowel movements that filled the toilet bowl with copious amounts of bright red blood. Minutes later, she felt dizzy and lightheaded and collapsed into her daughter's arms. The patient has a medical history of diabetes mellitus and hypertension. Her temperature is 99.0°F (37.2°C), blood pressure is 155/94 mmHg, pulse is 82/min, respirations are 15/min, and oxygen saturation is 99% on room air. The patient's exam is notable for fecal occult blood positivity on rectal exam; however, the patient is no longer having bloody bowel movements. The patient's lungs are clear to auscultation and her abdomen is soft and nontender. Labs are ordered as seen below.Hemoglobin: 7.1 g/dLHematocrit: 25%Leukocyte count: 5,300/mm^3 with normal differentialPlatelet count: 182,500/mm^3Two large bore IV's are placed and the patient is given normal saline. What is the best next step in management? Review Topic QID: 102631 Type & Select Correct Answer 1 Colonoscopy 0% (0/2) 2 CT abdomen 0% (0/2) 3 Fresh frozen plasma 0% (0/2) 4 Packed red blood cells 0% (0/2) 5 Type and screen 100% (2/2) M2 Select Answer to see Preferred Response SUBMIT RESPONSE 5 You have 100% on this question. Just skip this one for now. Take This Question Anyway (M2.GI.80) A 72-year-old male with a past medical history significant for aortic stenosis and hypertension presents to the emergency department complaining of weakness for the past 3 weeks. He states that, apart from feeling weaker, he also has noted lightheadedness, pallor, and blood-streaked stools. The patient's vital signs are stable, and he is in no acute distress. Laboratory workup reveals that the patient is anemic. Fecal occult blood test is positive for bleeding. EGD was performed and did not reveal upper GI bleeding. Suspecting a lower GI bleed, a colonoscopy is performed after prepping the patient, and it is unremarkable. What would be an appropriate next step for localizing a lower GI bleed in this patient? Review Topic QID: 106153 Type & Select Correct Answer 1 Nasogastric tube lavage 0% (0/2) 2 Technetium-99 labelled erythrocyte scintigraphy 100% (2/2) 3 Ultrasound of the abdomen 0% (0/2) 4 CT of the abdomen 0% (0/2) 5 Flexible sigmoidoscopy 0% (0/2) M2 Select Answer to see Preferred Response SUBMIT RESPONSE 2