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Jaundice (hyperbilirubinemia) is seen in critically ill patients and can occur due to prehepatic, intrahepatic, or posthepatic causes.
Biliary obstruction and acalculous cholecystitis are two common surgical problems requiring urgent intervention.
For acalculous or calculous cholecystitis, cholecystectomy removes the inflamed and ischemic gallbladder and prevents recurrence and thus is preferred in those able to tolerate the procedure. A cholecystostomy tube is indicated for nonsurgical candidates.
Diarrhea commonly occurs in critical illness (up to 60% of those on enteral feeds) and may be related to infection, medications, malabsorption, composition of the enteral feeds, or gastrointestinal disease.
Clostridium difficile should be ruled out as the cause of diarrhea in the ICU or any patient with risk factors (particularly antibiotics or contact) as morbidity and mortality increase with delay in treatment.
Fulminant Clostridium difficile can present as an ileus or with diarrhea in a toxic patient, and is associated with high mortality and frequent need for surgical intervention.
Studies are ongoing to determine the optimal medical and surgical management of Clostridium difficile. Currently for severe cases enteral vancomycin plus intravenous metronidazole is suggested ± subtotal colectomy or ileostomy with colon lavage.
Bowel obstruction should be ruled out prior to managing as pseudoobstruction.
Commonest causes of adult small bowel obstruction are adhesions and hernia, whereas commonest causes of adult large bowel obstruction are colon cancer, sigmoid volvulus, and stricture from diverticulitis.
Pseudoobstruction (nonmechanical obstruction) is managed by resuscitation, removing or limiting precipitants, using nasogastric or rectal tubes to relieve overdistension, and occasional endoscopic decompression or use of neostigmine in appropriate patients.
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Jaundice is characterized by yellow discoloration of the skin, conjunctivae, and mucous membranes as a result of widespread tissue deposition of the pigmented metabolite bilirubin. It can present as an isolated abnormality, or associated with specific hepatic and/or pancreatic dysfunction, or associated with multisystem organ dysfunction.
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In the intensive care setting, jaundice may be an important sign of a condition that requires ICU admission, such as acute cholangitis, or a new development in an already admitted patient, such as one with septic shock. Patient history, laboratory evaluation, appropriate imaging investigations, and a thorough understanding of those conditions that place a patient at increased risk for the development of hyperbilirubinemia will help narrow the broad differential diagnosis of jaundice and identify those conditions that require specific therapy.
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METABOLISM AND MEASUREMENT OF BILIRUBIN
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Bilirubin is a hydrophobic and potentially toxic compound that is an end product of heme degradation (Fig. 104-1 depicts bilirubin metabolism and excretion).1 The majority of bilirubin (70%-80%) is derived from degradation of hemoglobin from senescent erythrocytes, with a minor component of this being premature destruction of newly formed erythrocytes. The remaining 20% to 30% is mostly formed from breakdown of hemoproteins, such as catalase and cytochrome (CYP family) oxidases, in hepatocytes.
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