Endocrine/​Hematology/​Gastrointestinal/​Renal/​Integumentary Study Guide for the CCRN

Gastrointestinal

The gastrointestinal system is responsible for numerous bodily functions, including digestion, metabolism, and nutrient absorption. Disruption of this system can cause severe organ dysfunction and a range of complications due to the physical damage done. Review these common gastrointestinal conditions and understand the critical elements for treatment and nursing care.

Abdominal Compartment Syndrome

Patients with abdominal trauma complicated by shock are at risk for compartment syndrome. Compartment syndrome occurs when the pressures in the abdomen become so great that the organs inside are compressed, causing decreased perfusion and ischemia. Trauma to the abdomen may involve the bowels, external burns, hemorrhage, and excessive edema or ascites. Intra-abdominal pressure greater than \(20\,\text{mmHg}\) is diagnostic for abdominal compartment syndrome. Pressures are most commonly measured in the bladder by inserting a Foley catheter or, alternatively, an NG tube with a pressure transducer. Other indicators include an increased CVP, increased ICP, decreased CO, and decreased GFR. Imaging, such as abdominal ultrasound or CT, may also be utilized.

Patients with compartment syndrome should be treated carefully. Decompression must occur slowly to prevent reperfusion syndrome and cardiac arrest. The most effective treatment is a decompressive laparotomy where the surgeon will open the abdominal wall to release pressure. In many cases, patients will have an open belly, meaning the incision remains open for several days following surgery to prevent recurrence of compartment syndrome. This allows the wound to close slowly and reduce intra-abdominal pressures while healing.

Acute Abdominal Trauma

Patients with acute abdominal trauma must be monitored closely for a variety of concerns. Numerous organs are housed in the abdomen. Acute abdominal trauma may be due to blunt force or penetrating event. In particular, nurses should monitor for signs of injury in the spleen, liver, kidneys, and bowel.

Splenic Injuries

Splenic injuries most often occur in blunt trauma to the abdomen. The spleen is an extremely vascular organ and is not protected by the ribs, making it vulnerable in the abdomen. Patients often complain of left upper quadrant abdominal pain. Two signs, the Kehr sign and Cullen sign, are indicators of intra-abdominal bleeding, which may be seen with injuries such as splenic rupture. Severe injury may have signs of internal bleeding, such as dizziness, pallor, tachycardia, and hypotension.

• The Kehr sign is noted when the patient has radiating pain in the left shoulder.

• The Cullen sign is signified by bruising around the umbilicus.

Grades of Injury

Splenic injuries are identified by grades of injury. There are five grades:

• Grade 1 injury indicates a small, less than 1 cm, tear in the splenic capsule or a hematoma around the spleen.

• Grades 2 and 3 involve lacerations of the spleen itself, with Grade 2 being a tear smaller than 3 cm and Grade 3 being a tear greater than 3 cm.

• Grade 4 is when the laceration extends deep enough to damage the major splenic blood vessels, but any bleeding is contained within the spleen.

• Grade 5 injury represents massive bleeding that is not contained and freely enters the peritoneal cavity due to either a shattered spleen (rupture) or vascular injury that causes total devascularization.

Treatment

Treatment of splenic injuries is usually supportive. Most patients will be placed on strict bed rest, possibly receive blood transfusions, and have restricted activity orders for several weeks. If tears do not heal on their own, they may need surgical repair or embolization to prevent bleeding. Splenectomy is reserved for the most severe (Grade 5) injuries.

Hepatic Injuries

The liver, while slightly more protected than the spleen, is also prone to injury when abdominal trauma occurs. Complications from hepatic injury are the leading cause of death in those with abdominal trauma. Initial injury may not always be identified as symptoms may be nonspecific. Although, the most common symptom is RUQ abdominal pain and tenderness. Trauma can lead to pooling of blood within the liver, referred to as a hepatic hematoma. This increased pressure and volume of blood have a high risk of rupture and causing internal bleeding. Hepatic hematomas may not rupture until six weeks after injury, making close observation critical even after initial stability.

Diagnosis

To determine if a patient has a liver injury, liver enzymes should be monitored. These include alanine transaminase (ALT) and aspartate transaminase (AST). Elevated liver transaminase levels are concerning for injury. Most commonly, an abdominal CT scan can indicate the presence and severity of injury. Liver ultrasound and MRI may be used as well. A chest X-ray may also show an elevation of the right hemidiaphragm, indicating liver trauma. Liver injuries are then graded from Grade 1 to Grade 6, based on the severity of injury:

• Grade 1 injuries involve just tears in the capsule, less than 1 cm, and/or less than 10% surface area liver hematoma.

• Grades 2 and 3 injuries involve lacerations of the parenchyma, Grade 2 being less than 3 cm tear and/or 10% to 50% surface area liver hematoma. Grade 3 is characterized as a tear greater than 3 cm and/or greater than 50% surface area hematoma. In Grade 3, you can also see active bleeding that is contained within the liver.

• Grades 4 and 5 injuries involve destruction of the liver lobes due to burst injury. Grade 4 injuries involve 25% to 75% destruction, whereas Grade 5 injuries involve greater than 75% destruction. Internal bleeding is also seen in these severe injuries.

• The final grade and most severe injury, Grade 6, is indicated by complete avulsion, or total detachment, of the liver from the surrounding structures. This results in massive hemorrhage and has a very high mortality rate.

Treatment

Treatment of liver injury depends on the patient’s status and the severity of the injury. Being a highly vascular organ, hemorrhage is a common complication, and some blood vessels may require ligation to stop the bleeding. Some patients with a small hematoma or injury may just need monitoring and supportive care. Patients should be adequately hydrated and fluid deficits should be treated with IV fluids and blood products as indicated. If patients are unstable or actively bleeding, an exploratory laparotomy may be required to assess the extent of damage, and surgical repair of any lacerations may be necessary.

Kidney and bowel injuries will be discussed later in this guide.

Acute GI Hemorrhage

Gastric ulcers are the primary cause of acute GI hemorrhage. Other causes include esophageal varices, inflammation, infection, abnormal blood vessels, hemorrhoids, tears, and cancerous or benign tumors. Hemorrhages, though, may occur in both the upper and lower GI tracts. Symptoms of hemorrhage include abdominal pain, abdominal distension, melena, black/tarry stools, coffee-ground emesis, tachycardia, and hypotension.

Treatment

Treatment focuses on stopping the source of the bleeding. Esophagogastroduodenoscopy may be performed to identify sources of bleeding in the upper GI tract and a colonoscopy in the lower GI tract. . During these procedures, cauterization or placement of metal clips may be performed if active lesions are found.

In patients with esophageal varices, or enlarged veins in the esophagus, band ligation can be used to prevent and treat bleeding varices. Ruptured esophageal varices are a medical emergency with a high mortality rate. Once ruptured, endoscopic treatment becomes more difficult and may result in the need for additional interventions such as balloon tamponade (such as a Blakemore or Minnesota tube) or a Transjugular Intrahepatic Portosystemic Shunt (TIPS) procedure. Medications can also help manage varices: octreotide reduces portal hypertension and is used acutely to control bleeding, while non-selective beta blockers (e.g., propranolol, nadolol) are used long term to prevent bleeding.

In the event of tumors or failed endoscopic intervention, surgery may be required to identify and remove the source of bleeding or repair damaged tissue. In some cases, a partial or total resection of the small or large intestine may be necessary if severely damaged or bleeding cannot be controlled. Patients should have supportive fluid and blood replacement as needed and be assessed for the need for medications such as corticosteroids, antibiotics, antacids, and proton pump inhibitors (pantoprazole). Long-term therapy should focus on the prevention of future GI bleeds.

Bowel Infarction/Obstruction/Perforation

Bowel infarction occurs when blood flow is restricted to the bowel due to damaged or blocked arteries. A common type of bowel infarction is known as mesenteric ischemia, which primarily affects the small intestine. Mesenteric ischemia can be acute due to a blood clot or chronic due to progressive buildup and compression of the internal artery. Bowel obstruction occurs when material, usually stool, becomes lodged somewhere along the intestine and is unable to pass. This may be due to paralytic ileus, constipation, or bowel constriction. Adhesions may cause bowel obstruction as narrowed areas of bowel can cause increased difficulty in passing stool. Adhesions can occur following abdominal trauma, surgery, or previous bowel exploration. Bowel obstruction becomes an emergency if the bowel then perforates due to infarction and ischemia.

Diagnosis and Treatment

These conditions can be diagnosed through abdominal CT, X-rays, ultrasound, MRI, and procedures such as endoscopy or even exploratory surgery.

Acute mesenteric ischemia requires immediate surgery to remove the blood clot and any damaged tissues, whereas chronic ischemia can be treated with the use of minimally invasive angioplasty or medications such as vasodilators to improve blood flow if the primary problem is vessel constrictions and not blockage. Bowel infarction can quickly lead to sepsis and shock. If not treated, it may result in death.

Treatment for bowel obstruction involves NPO status, abdominal decompression, IV fluids, and monitoring for the passage of the obstruction. In the event of a bowel infarct, surgical resection is required to remove the affected bowel. In critically ill patients, bowel obstruction may occur due to decreased peristalsis and medication administration. Prevention of obstruction is key, and patients should be on a variety of bowel prep therapies to prevent this from occurring.

Gastroesophageal Reflux

Gastroesophageal reflux (GERD) is not often considered a critical care condition. However, complications of GERD can become very critical to the patient. GERD is a lower esophageal sphincter issue that occurs when the sphincter opens and allows stomach contents to regurgitate. Chronic damage to the esophagus may cause Barrett’s esophagus, making patients more prone to esophageal adenocarcinoma.

Diagnosis and Treatment

Patients with GERD often complain of heartburn, dysphagia, belching, sore throat, chest pain, and hoarseness. Ambulatory esophageal reflux monitoring and/or endoscopy may be used to diagnose this condition. Proton pump inhibitors are used to reduce gastric acid secretion that may cause reflux. Patients should be educated on common triggers of GERD, including caffeine, alcohol, chocolate, and acidic foods. Scheduling food intake should also be taken into consideration, making sure that the last snacks and meals are approximately two to three hours prior to lying down to sleep.

GI Surgeries

Several procedures may be performed on and around the GI system. The most common of the GI surgeries in critical care are outlined below.

Abdominal Organ Resection

Abdominal organ resections are surgical procedures where removal of part or all of an abdominal organ is required due to some medical pathology. The organs that can be involved in an abdominal organ resection include the intestines, stomach, esophagus, liver, pancreas, spleen, and adrenal glands/kidneys. Note: The kidneys may be part of either abdominal or genitourinary resection.

Abdominal organ resection may be required due to organ injury/death, tumor growth, or infection. Resections can be performed either laparoscopically or via open abdominal incision. Nurses should monitor patients closely for complications from the procedure, including bleeding, compartment syndrome, electrolyte imbalance, and infection.

Whipple Procedure

A Whipple procedure is a surgical procedure performed to remove the head of the pancreas, the duodenum, the gallbladder, and the bile duct. It is also known as a pancreaticoduodenectomy. It is most commonly recommended in the event of pancreatic cancer. It can also be performed to treat tumors located in the duodenum or bile duct, treat chronic persistent pancreatitis (may additionally require complete pancreatectomy), and address trauma to the associated organs.

The Whipple procedure can be performed via open abdominal, laparoscopic, or robotic surgery. It is a prolonged surgery lasting a minimum of four hours and up to 12 hours. Complications of the procedure include bleeding, infection, poor stomach emptying, pancreatic fistula, bowel obstruction, enzyme leakage, sepsis, and diabetes.

Esophagectomy

Esophagectomy and esophagogastrectomy are procedures indicated in the event of esophageal or gastric cancer. In the esophagectomy procedure, part or all of the esophagus is removed. The distal portion of the stomach is then reconstructed to replace this portion of the esophagus. In the esophagogastrectomy procedure, lymph nodes and the upper stomach have to be removed in addition to the esophagus. Feeding tubes are used initially to allow for healing and for the patient to regain the ability to swallow, with a gradual transition to liquids, then small, frequent meals.

Bariatric Surgery

Bariatric surgery is another type of GI surgery that is becoming increasingly common. This procedure is reserved for patients who are morbidly obese looking for assistance in losing weight. The procedure may be completed both with open incisions and laparoscopic techniques. There are several styles of bariatric surgery, including banding, sleeve gastrectomy, Roux-en-Y (staples and band), and gastric ballooning.

When caring for patients post-bariatric surgery, careful monitoring and precautions must be taken to prevent complications. Respiratory complications are common after this type of surgery, not necessarily due to the surgery itself, but because obesity and its associated comorbidities make surgery and anesthesia a higher risk overall, with atelectasis being the most common type of respiratory complication. General surgical complications like bleeding, thrombosis, and infection can occur, but bariatric procedures also have their own specific risks described below.

Stomach rupture is when the staple line does not heal correctly, resulting in a hole and leakage of stomach contents into the abdominal cavity. This can happen due to technical issues, poor healing factors, and high intra-abdominal pressure. Avoid manipulating or irrigating NG tubes placed surgically, and encourage dietary compliance to help prevent this. Diet orders typically start with an NPO status and then transition to liquids, soft foods, and eventually a regular bariatric diet. A bariatric diet focuses on slowly eating smaller meals containing high protein, low sugar, and low fat. These diet restrictions are also important to avoid dumping syndrome, which occurs when food moves too quickly from the stomach to the small intestine, causing symptoms such as nausea, vomiting, abdominal pain, bloating, diarrhea, dizziness, and tachycardia.

Hepatic Failure/Coma

The liver is an important organ in the abdomen. Several hepatic complications can cause serious illness in patients.

Portal Hypertension

Portal hypertension is a condition that occurs when there is scarring or damage to the liver, most commonly from cirrhosis, that prevents normal blood flow. This increased pressure forces blood to reroute through collateral veins, especially in the GI tract, leading to esophageal varices and portal hypertensive gastropathy. Portal hypertension is most often caused by liver disease or cirrhosis but can also occur in certain vascular or hematologic disorders.

Diagnosis and Treatment

Diagnosis of portal hypertension is made after a variety of lab tests, abdominal ultrasound, CT, or invasive hemodynamic measurement of the hepatic venous pressure gradient. A value greater than 5 mmHg is consistent with portal hypertension. Patients will need upper endoscopy on a routine basis for esophageal varices screening and band ligation or potential TIPS for treatment (see GI bleeding section). Nonselective beta-blockers, such as propranolol, are used to reduce portal pressure and prevent bleeding from esophageal varices. Nurses should monitor patients closely for status changes, especially with known esophageal varices, as rupture of these becomes immediately life-threatening and can result in death.

Cirrhosis

Cirrhosis is a chronic liver disease caused by long-term liver injury. It is classified by fibrotic and structural changes that reduce liver function and filtration. There are two types of cirrhosis, compensated and decompensated. In compensated cirrhosis, the patient’s symptoms are often nonspecific and can include abdominal discomfort or subtle lab abnormalities. Decompensated cirrhosis is the advanced, symptomatic stage where the liver fails. Some specific signs seen are palmar erythema and spider angiomata. This causes complications such as:

• ascites—fluid accumulation in the abdomen due to portal hypertension and sodium/water retention

• esophageal varices—dilated veins in the esophagus caused by portal hypertension

• hepatic encephalopathy—brain dysfunction, such as confusion or tremors, from toxins like ammonia build up

• jaundice—yellowing of skin and eyes caused by bilirubin buildup due to impaired liver metabolism and excretion

• coagulopathy—easy bruising and bleeding from reduced production of clotting factors

Three types of decompensated cirrhosis include alcoholic, post-necrotic, and biliary.

Diagnosis

Patients with cirrhosis may present with thrombocytopenia and prolonged PT/INR. Other lab values are decreased albumin levels andincreased ammonia levels, bilirubin, and AST/ALT. Hyponatremia is frequently seen due to serum dilution with ascites. Radiologic imaging may show enlarging and hardening of the liver.

Treatment

Treatment of cirrhosis involves correcting electrolyte imbalances and restricting sodium and fluids. Potassium-sparing diuretics may be used to reduce ascites and edema. Paracentesis can be used to relieve ascites by inserting a catheter into the peritoneum to remove accumulated fluid. Intravenous albumin supports blood volume and is often used with paracentesis to prevent circulatory complications. Patients should be educated to weigh themselves daily and report weight gain to their provider, as well as avoid NSAID medications due to decreased renal perfusion. Ultimately, though, for curative outcomes, a liver transplant is required.

Fulminant Hepatitis

Fulminant hepatitis, also referred to as acute liver failure, can occur spontaneously in previously healthy patients without liver disease or cirrhosis. This condition causes severe liver injury that then causes widespread organ dysfunction. The most common cause of fulminant hepatitis is viral hepatitis, specifically hepatitis B and acetaminophen overdose. Other causes include exposure to toxins, illicit drug/mushroom exposure, and viruses. Patients may have underlying genetic conditions, such as Wilson’s disease, that may also contribute to this condition.

Patients may present to the emergency department with jaundice, headache, agitation, disorientation, drowsiness, confusion, tremors, and seizures. Patients with fulminant hepatitis should be monitored for changes in level of consciousness, respiratory distress, cardiovascular instability, infection, and renal failure. Coagulopathy and hypoglycemia may also occur. Cerebral edema is a common complication resulting from hepatic encephalitis. Medications can be given depending on the cause. For example, antivirals for hepatitis or acetylcysteine for acetaminophen overdose. However, patients will require liver transplants to cure this condition. For those for whom a liver transplant is not performed, mortality exceeds 80%.

Drug-Induced Liver Injury

Many drugs are metabolized by the liver. Chronic use, misuse, or poor reaction to these medications can cause significant liver damage. Some prescription medications that can cause hepatic failure include broad-spectrum antibiotics, antifungal medications, anticonvulsants, statins, and chemotherapy agents. Over-the-counter medications that most commonly cause hepatic damage include acetaminophen (overdose) and herbal supplements.

Patients can be asymptomatic or present with symptoms of drug-induced liver injury, including fatigue, weakness, abdominal pain, nausea/vomiting, dark urine, jaundice, and mental status changes (encephalitis). Symptoms can develop rapidly or over time. Patients may experience elevated hepatic enzyme levels (ALT and AST) and electrolyte imbalance. Diagnosis is typically made with the clinical history and lab values. Diagnosis can be supported with liver biopsy and radiographic imaging as well.

The primary treatment for drug-induced hepatic failure starts by stopping the offending medication/drug. Supportive measures should be used to treat the patient’s other symptoms. These can include fluid resuscitation, medication antidotes or reversal agents, and frequent neurologic checks. If damage is severe and the recovery margin is slim, a liver transplant may be required. Patients should understand that treatment and resolution of injury may take several months or may become a chronic issue depending on the level of damage and potential for recovery.

Liver Lab Values

Liver function tests play an important role in the interpretation of diseases/conditions involving the liver. Remember to review normal values and important indications regarding elevated or decreased levels of the following:

• bilirubin (direct, indirect, total, and urine)
• total protein (albumin, globulin, and albumin/globulin (A/G) ratio)
• AST/ALT/ ALP
• serum ammonia
• lipids
• clotting factors

Malnutrition and Malabsorption

Malabsorption is often a precursor to malnutrition. Malabsorption occurs when the gastrointestinal tract is unable to process and absorb the nutrients needed. This may occur in the event of intestinal trauma, infection, anesthesia, radiation, or multiorgan failure. Patients at increased risk for malabsorption include those with GI disorders or surgery, those with liver or biliary disease, the elderly, and ICU patients who are intubated with prolonged NPO times or those on vasopressor medications that restrict blood flow to the intestines. Patients with malabsorption and malnutrition are at increased risk for musculoskeletal problems, infection, respiratory failure, heart concerns, and delayed healing.

Symptoms and Treatment

Signs of malabsorption and malnutrition include bloating, abdominal cramping, diarrhea, muscle wasting, weight loss, fatigue, amenorrhea, steatorrhea, vitamin deficiencies, and electrolyte imbalances. Common labs drawn in the event of suspected malabsorption include complete blood count, electrolytes, ferritin, vitamin B12, albumin, and protein. Treatment involves addressing the underlying cause if possible. Nutritional support includes oral supplementation when possible, enteral feeding (tube feeding), or TPN (total parenteral nutrition) through the venous system, which may need to be implemented depending on the severity of nutrient imbalances. Patients in the ICU with NPO status should have their diets advanced as quickly and safely as possible to prevent malabsorption and malnutrition.

Pancreatitis

Pancreatitis may be acute or chronic. Chronic pancreatitis can be caused by chronic alcohol abuse, smoking, or even a genetic condition that can have acute flares. Acute pancreatitis often occurs due to chronic alcoholism or cholelithiasis. In occasional cases, pancreatitis has no determinate cause. Tetracycline, thiazides, acetaminophen, and oral contraceptives have also been known to cause acute pancreatitis at times.

Symptoms and Diagnosis

Symptoms of acute pancreatitis include acute midepigastric to left upper quadrant abdominal pain, nausea, vomiting, and abdominal distension. Abdominal pain may be worse after eating and better when sitting up or leaning forward. Acute shock, respiratory distress syndrome, and multiorgan distress may develop. Patients with acute pancreatitis will have serum lipase levels greater than three times the normal level and an elevated amylase. CT, MRCP, and endoscopic or abdominal ultrasounds may be used to assist in diagnosis.

Treatment

Treatment of pancreatitis is supportive. IV fluids, analgesics, antiemetics, and antibiotics may be used to treat fluid deficits, pain, nausea/vomiting, and any concern for infection or secondary necrosis. Strict NPO status with supplemental TPN may provide the patient with nutrients. Endoscopic retrograde cholangiopancreatography (ERCP) can be used to remove gallstones or open narrowings of the bile ducts. Surgical removal of the gallbladder and biliary duct may be indicated if pancreatitis is recurrent due to concerns with these structures. Prevention of pancreatitis is recommended. Patients should be instructed on smoking cessation and decreased alcohol consumption. Patients should be educated on having small and frequent meals, limiting fat intake, increasing fresh fruits and vegetables, and avoiding alcohol and fried foods. Pancreatic enzymes are primarily used in chronic pancreatitis when the pancreas can no longer produce enzymes that are crucial for digestion. These enzymes should be taken with every meal and snack.

Gastrointestinal Drains

Drains are commonly used to help remove fluid or blood when invasive procedures are performed within the abdomen. Review the common types of drains and the reasons for their placement.

• simple drains—allow passive drainage of fluid (e.g., Penrose)

• closed suction drains—fluid removed by suction and deposited into a closed collection device (e.g., Jackson-Pratt® or Hemovac®)

• multi-lumen drains—double or triple lumen devices that work by allowing venting of air in one lumen while the drainage is forced out of the larger lumen

• percutaneous drainage catheter—inserted through the skin under imaging; usually continuous drainage; may need to be irrigated

Monitor the site for erythema and edema. Insertion sites may need wound care and/or dressing changes. Ensure drains stay patent and sealed. Empty drains frequently, document output, and report any abnormalities to the physician.