20 Gastrointestinal Bleeding Siobhan A. Corbett Objectives 1. To outline the initial management of a patient with an acute GI hemorrhage. 2. To differentiate upper versus lower GI hemor- rhage. 3. To discuss the differences in evaluation and man- agement of the patient presenting with hemateme- sis, melena, hematochezia, and guaiac positive stool. 4. To discuss medical versus surgical management of the common causes of GI hemorrhage. Case History A 65-year-old man presents complaining of the passage of bright red blood and clots per rectum earlier that evening. This episode was pre- ceded by mild lower abdominal cramping. The patient denies any nausea, vomiting, or abdominal pain at this time, but he states that he feels “light-headed.” He reports one episode of rectal bleeding 2 months prior that was limited, and he did not seek medical advice at that time. His past medical history is significant for hypertension. The patient denies any past surgical history. He takes one baby aspirin per day and denies any allergies. He is a nonsmoker and uses only occasional alcohol. Review of Systems The patient denies change in bowel habits, has no history of divertic- ulosis, and reports no recent weight loss. 355 356 S.A. Corbett Physical Exam Temperature 99.0°F; blood pressure 90/45; heart rate 122; respiratory rate 25. The patient appears pale and anxious. Head, ears, eyes, nose, and throat exam is normal; his neck veins are flat. Lungs: Clear to ausculatation with equal breath sounds bilaterally. Heart: RR, sinus tachycardia, no murmurs. Abdomen: Active bowel sounds, soft, nontender; no masses or organomegaly. Rectal: Gross blood on digital exam, prostate is normal. Extremities: Skin is cool and clammy. His radial pulses are equal, but they are weak and thready. Initial Management Assess the Severity of Bleeding The first step in managing a patient with a gastrointestinal (GI) hem- orrhage is to assess the rate of bleeding and to estimate the blood loss (Table 20.1; Algorithm 20.1). Patients may present in a variety of ways. For example, they may have anemia from occult bleeding, but they otherwise may be asymptomatic. Alternatively, patients may exhibit gradual bleeding with black or tarry stools that commonly is referred to as melena. Black stools occur as the result of oxidation of heme by bacterial and digestive enzymes. A major bleeding episode is likely to have occurred if there is profuse vomiting of blood (hematemesis) or bright red blood per rectum (BRBPR or hematochezia), accompanied by supine hypotension or a postural blood pressure or pulse change. Other findings indicative of hypovolemia include a weak, thready pulse, moist, clammy skin, decreased skin temperature of the distal extremities, tachypnea, and mental status changes (confusion, agita- Table 20.1. Physical findings in hemorrhagic shock.a Class I Class II Class III Class IV Blood loss (mL) <750 750–1500 1500–2000 >2000 Blood loss UP to 15% 15%–30% 30%–40% >40% Pulse rate <100 >100 >120 >140 Blood pressure Normal Normal Decreased Decreased Pulse pressure (mmHg) Normal Decreased Decreased Decreased Respiratory rate 14–20 20–30 30–40 >35 Urine output (mL/h) >30 20–30 5–15 Negligible CNS/mental status Slightly Mildly Anxious, Confused, anxious anxious confused lethargic a Alcohol or drugs (e.g., beta-blockers) may alter physical signs. Source: Adapted from American College of Surgeons. Shock. In: Advanced Trauma Life Support Manual. Chicago: American College of Surgeons, 1997:87–107. Reprinted from Nathens AB, Maier RV. Shock and resuscitation. In: Norton JA, Bollinger RR, Chang AE, et al, eds. Surgery: Basic Science and Clinical Evidence. New York: Springer-Verlag, 2001, with permission. 20. Gastrointestinal Bleeding 357 Algorithm 20.1. Algorithm for initially manag- ing a patient presenting with GI bleeding. Hematemesis, Melena or Hematochezia Assess the severity of Bleeding Resuscitate and Stabilize the Patient Evaluate the Patient: History and Physical Determine the Bleeding Site Manage Specific Bleeding Problem tion, or obtundation). The overall approach to managing the patient is determined by the rate of bleeding, since this reflects the likeli- hood that the hemorrhage will stop spontaneously. Patients with a rapid rate of bleeding may require a laparotomy, so it is important to involve a surgeon early. Case Presentation: Assessment The history of BRBPR accompanied by clots indicates that this patient may have a significant GI bleed. The patient’s vital signs are indicative of hypovolemic shock. This diagnosis is supported by his physical findings. He appears pale and anxious. He has a weak, thready pulse, and cool, clammy skin. Taken together, this would indicate a class III/IV hemorrhage. Resuscitate and Stabilize the Patient Patients who have evidence of massive blood loss should be resusci- tated immediately. The airway is assessed to ensure that there is no obstruction, and oxygen administration is required for all patients. Obtunded patients, those who cannot protect their airway, and those with massive vomiting that presents an aspiration risk should be endo- tracheally intubated, and ventilator support should be provided for adequate respiration. Large-bore intravenous access (¥2) with 18-gauge or larger catheters should be placed. Central venous access with a Swan-Ganz introducer (8.5Fr) may be helpful for rapid infusion if peripheral access is inadequate, but it is hazardous to place it in a hypo- volemic patient with empty, flat neck veins. If a central line is required, 358 S.A. Corbett a femoral line is a reasonable alternative that can be replaced by upper extremity access once the patient is stabilized. At the time of the insertion of the intravenous catheters, blood should be sent for type and crossmatch, and six units of packed red blood cells should be made available. Additional laboratory evalua- tion should be performed to determine the complete blood count (CBC), chemistries [including electrolytes, blood urea nitrogen (BUN), creatinine, liver function tests], and a coagulation profile. It is important to note that, in the early stages of hemorrhage, the hemat- ocrit level may not reflect the extent of the blood loss. Normal saline and Ringer’s lactate are the fluids of choice used to resuscitate a patient suffering from class I or class II shock. The crys- talloid replacement should be in a quantity sufficient to replace plasma losses plus the interstitial loss and should be on the order of 3mL of crystalloid for each 1mL of estimated blood loss. In a young person, up to 3L of crystalloid may be given at the rate of 1L every 15 to 30 minutes until the clinical signs of shock have been corrected. Adequate resuscitation can be monitored by a slowing of the heart rate and a return of urine output. However, it is important to be cautious about overloading the intravascular compartment in those patients with cardiac or renal impairment. If the bleeding has ceased, crystalloid volume replacement usually will be adequate therapy for class I or class II hemorrhage, although patients with preexisting medical con- ditions may require earlier transfusion at this level. Patients present- ing with class III or class IV shock who are estimated to have lost more than 35% of their circulating blood volume are given type- specific blood in addition to crystalloid until crossmatched blood is available. (In the true emergency, O negative blood may be required.) Foley catheter placement to monitor urine output is essential in this instance. Patients with persistent hemodynamic instability or evidence of ongoing blood loss should be monitored closely and should be pre- pared for possible laparotomy. Remember: anticipate that unstable patients who have required multiple blood transfusions may become cold and develop dilutional coagulopathy that will increase the morbidity and mortality of an operative procedure. Under these circumstances, replacement of clot- ting factors with fresh frozen plasma is important, and it takes time for the transfusion services to make this component necessary. Therefore, think ahead. Cryoprecipitate may be required, but it should not be given unless factor VIII deficiency is demonstrated. Platelets should be administered if the platelet count is less than 50,000. Case Discussion: Resuscitation Immediate action is required to treat class III/IV hemorrhage. Make sure that the patient’s airway is secure and provide supplemental oxygen. Start 2 large-intravenous bore (IV) lines and begin resuscita- tion with a 500-mL to 1-L bolus of crystalloid solution. Send blood for type and crossmatch and additional laboratory values including CBC, chemistries, and coagulation profile. Six units of packed red blood cells 20. Gastrointestinal Bleeding 359 (pRBCs) should be available. Place a Foley catheter to monitor urine output. Reassess vital signs frequently. Evaluating the Patient History A brief, pertinent history from the patient regarding the degree of hematemesis, melena, or hematochezia contributes to an assessment of the degree of blood loss and the severity of the bleed. Inquiring about the duration of the symptoms also may help determine the rate of blood loss. As a rule, melanotic stools typically originate from the upper GI tract and maroon stools from the distal ileum or right colon, and bright red blood is indicative of bleeding from the left colon. The differential diagnoses for GI bleeding in the adult are listed in Table 20.2. Additional history should include associated symptoms that may indicate the source of the bleeding: 1. A history of nasopharyngeal lesions, trauma, or surgery should be obtained to exclude an oral or nasopharyngeal source for hematemesis. 2. A history of known ulcer disease, gastroesophageal reflux, prior epigastric pain relieved by antacids, or excessive use of aspirin, nonsteroidal antiinflammatory drugs (NSAIDs), or steroids may implicate the esophagus, stomach, or duodenum as the source. Alternatively, a known history of diverticular disease or angiodys- plasia may implicate a lower GI source.