Diarrhea in the ICU

Diagnosis and management of diarrhea in the intensive care unit

Related conditions

Diarrhea in the critical care setting

Hospital-acquired diarrhea

Nosocomial diarrhea

1. Description of the problem

What every clinician needs to know

Diarrhea is defined as more than 3 bowel movements per day and stool weight greater than 200-300 grams per day or volume greater than 250 mL per day.

Acute diarrhea is defined as a duration less than 4 weeks.
Chronic diarrhea is defined as a duration greater than 4 weeks.
Hospital-associated diarrhea is defined as diarrhea developing in a patient hospitalized for more than 3 days.
Identifying the cause of diarrhea is vital for appropriate treatment.

Epidemiology

Hospital-acquired diarrhea is quite common, with diarrhea reported occurring in the range of 40-90% in ICU patients. Certain patient populations are at highest risk, such as extensive burn patients.

Clostridium difficile is the leading cause of hospital-acquired diarrhea. Lack of previous colonization with Clostridium difficile is the highest risk for developing symptomatic infection.
Reported risk factors for diarrhea in the ICU include fever, hypothermia, malnutrition, hypoalbuminemia, cessation of oral feeding, and the presence of an infection site.

Pathophysiology

Diarrheal illnesses may be divided into categories by pathophysiologic mechanism, although some diseases may cause diarrhea by more than once mechanism:

Inflammatory diarrhea

May be a result of invasive infections.
Immune-mediated (i.e. inflammatory bowel disease, graft-versus-host disease).
May lead to bloody stools and stool with mucus/pus.

Secretory diarrhea

A result of mucosal secretion of electrolytes and fluid into intestinal lumen and may also be associated with decreased absorption.
Production of “secretagogues” by neuroendocrine tumors such as gastrin, vasoactive intestinal polypeptide.
Leads to watery and voluminous diarrhea.

Osmotic diarrhea

A result of an osmotically active agent in the intestinal tract that cannot be absorbed.
Common culprits: medications such as magnesium hydroxide/phosphate or sulfate; antacids containing magnesium; lactose in lactase-deficient individuals, sorbitol-containing products; enteral feeds.
Leads to watery and intermittent diarrhea.

Malabsorption

Reduction in mucosal surface area available for absorption (i.e. surgical resection or extensive mucosal ulceration), ileal resection leading to bile salt malabsorption, or lack of pancreatic enzymes.
Stool may appear oily, foul-smelling.

Motility

Gut hypermotility leading to decreased contact of solutes to mucosal surface.
Associated with vagotomy, hyperthyroidism, diabetic autonomic neuropathy.

Hospital-associated diarrhea (by categories)

Non-infectious causes

Enteral feeding

Osmotic

Malabsorption

Medications

Intestinal ischemia

Bacterial overgrowth

Fecal impaction

Endocrine disorder

Exacerbation of underlying disease such as inflammatory bowel disease
Infections

Clostridium difficile

Rotavirus

Norovirus

Salmonella

Cryptosporidium

Microorganisms not typically associated with diarrhea: Candida albicans, Klebsiella oxytoca, Staphylococcus aureus

Hospital-associated non-infectious diarrhea (in more detail)

Enteral feeding

Most common cause of ICU related diarrhea.

Enteral nutrition > 60% of energy target

Mode of feeding (continuous vs. gravity vs. intermittent) plays more of a factor than site of feeding (gastric vs. jejunal) for risk of diarrhea. Continuous feeding is associated with the least risk for diarrhea.

The composition of enteral feeds may also play a factor in causing diarrhea:

Carbohydrate load

Fat

High osmolarity (acquired lactose intolerance may contribute to this)

Bacterial contamination

Lack of non-absorbable fiber
Medications may lead to diarrhea

Antibiotics

Gastric acid suppressants (histamine-2 receptor antagonists and proton pump inhibitors)

Magnesium-containing oral medications

Sorbitol-containing compounds/products

Laxatives (inadvertent)

Oral hypoglycemic (metformin)

Anti-arrhythmics (quinidine)

Theophylline

Prokinetic agents (metoclopramide)
Steatorrhea

Associated with the following in the ICU: shock, sepsis, diabetes, cardiac arrest, hyperlactacidemia, mechanical ventilation and hemodialysis

Caused by pancreatic insufficiency from septic shock

Caused by bile salt malabsorption
Endocrine disorders

Adrenal insufficiency

Hyperthyroidism

Diabetes
Intestinal ischemia (colon, small intestine)

At-risk patients age >65 years

Etiology

Hypotension, shock (colon affected > small intestine)

Thromboembolic (colon, small intestine), hospital-associated infectious diarrhea

Hospital-associated infectious diarrhea

Clostridium difficile (a bacteria classified as an anaerobic gram-positive bacillus that produces spores and toxin)

Most common cause of health care associated diarrhea

Incidence of 2% in the hospitalized setting and 4% in the intensive care unit

Risk factors for developing Clostridium difficile infection

Exposure to antibiotics

Exposure to Clostridium difficile

Comorbid conditions (such as gastrointestinal surgery, Inflammatory bowel disease)

Medications that reduced gastric acid

Elderly (age >60 years)

Transmission: fecal-oral

Common source: person-person, contact with contaminated surface or item

Incubation/duration: unknown, possibly 7 days/requires treatment
Salmonella (a bacteria classified as a facultative intracellular gram-negative bacillus) (non-typhoid)

35% of cases in the United States occur in the health care setting.

Reportable to public health department

Risk factors for developing Salmonella infection

Age <20 years and >70 years

Immunocompromised (such as HIV, chemotherapy)

Aplastic anemia

Transmission: fecal-oral

Common source: classically contaminated food-poultry, eggs; person-person; contaminated equipment (i.e. endoscopes)

Incubation/duration: 12-72 hours/4-7 days
Rotavirus (a non-enveloped segmented double-stranded RNA virus)

Risk factors

Children between the ages of 2-3 years

Elderly

Transmission: fecal-oral

Common source: contact with infected individual

Incubation/duration: 2 days/3-8 days
Norovirus (a single-stranded RNA virus)

17-46% hospital-acquired in children

Risk factors

Lack of immunity to norovirus

Transmission: fecal-oral, emesis-oral

Common source: contact with infected individual

Incubation/duration: 12-48 hours/24-60 hours
Cryptosporidium (a parasite in the class Protozoa)

Risk factors

Immune suppression

Transmission: fecal-oral

Common source: contaminated water

Incubation/duration: 2-10 days /1-2 weeks (may be chronic in immune-suppressed patients)

Clinical features of non-infectious/noninflammatory diarrhea

Non-bloody
Absence of fever
Osmotic diarrhea: stool output predominately occurs with feeding
Malabsorptive diarrhea: increased stool fat, foul smelling

Clinical features of infectious or inflammatory diarrhea

Symptoms and signs of possible infection or inflammatory diarrhea

stool with blood or mucus

fever

severe abdominal pain

vomiting

toxic megacolon: fever and abdominal pain associated with abdominal distention and tenderness, see below for diagnostic testing

intestinal ischemia: potential symptoms: bloody diarrhea, abdominal pain

hemolytic uremic syndrome (occurs 5-10 days after onset of diarrhea): microangiopathic hemolytic anemia, thrombocytopenia, and renal failure
Clostridium difficile

potential symptoms: foul-smelling stool, watery diarrhea, abdominal cramps, fever, nausea

severe disease: abdominal pain, lack of diarrhea, fever
Salmonella

potential symptoms: fever, extra-intestinal symptoms (i.e. arthralgia, arthritis), sepsis
Rotavirus

potential symptoms: profuse watery diarrhea, vomiting
Norovirus

potential symptoms: fever, diarrhea, nausea, abdominal pain, vomiting
Cryptosporidium

potential symptoms: watery diarrhea, fever, abdominal pain, nausea and vomiting

chronic: bulky/foul-smelling stool, weight loss

3. Diagnosis

Establishing the diagnosis

Obtain a detailed history and physical exam to help focus evaluation.

duration of diarrhea
onset in relation to hospitalization
characteristics of diarrhea: Is it bloody, watery/voluminous, postprandial?
weight loss
travel history
dietary history
medications
sick contacts

General diagnostic tests

Stool studies
Serum electrolytes, albumin, and complete blood cell count and serum albumin
Blood cultures if febrile

Specific diagnostic tests

Acute diarrhea hospitalized for <3 days, admitted to the ICU (diagnostic tests to include community-acquired infections)

stool culture (Salmonella, Shigella, Campylobacter; may also include Aeromonas and Plesiomonas)
stool ova and parasites
stool Clostridium difficile
stool E. coli 0157 (if bloody)
stool Yersinia (if bloody)
serum: electrolytes, complete blood cell count
stool Rotavirus (if watery): reverse transcriptase PCR (most sensitive) or enzyme-linked immunoassays VP2/VP6

Acute diarrhea evaluation hospitalized for 3 days or more

similar to acute diarrhea evaluation <3 days hospitalization
routine stool cultures may be rejected due to low yield. exceptions: neutropenia <0.5 x 10⁶ cells/mL, HIV, extraintestinal manifestation (i.e. salmonella: erythema nodosum, polyarthritis, fever of undetermined origin), patient > 65 years with comorbidities and end-organ deterioration, possible hospital outbreak
bloody diarrhea with or without abdominal pain after shock or hypotension: to consider CT scan for ischemia evaluation

Chronic diarrhea hospitalized for less than 3 days, admitted to the ICU

stool ova and parasites
stool Clostridium difficile
serum electrolytes (to include magnesium, calcium, zinc), albumin
complete blood cell count
serum thyroid-stimulating hormone
celiac antibodies (tissue transglutaminase IgA, anti-endomysial antibody igA, serum IgA level)
stool electrolytes (sodium, potassium)

calculate stool osmotic gap (290 mOsm/kg – 2 x (sodium + potassium)

stool pH <6 indicates carbohydrate malabsorption
alpha-1 antitrypsin (A1A) level (stool and serum

calculate A1A clearance = [fecal A1A concentration x stool volume/24hrs]/A1A serum concentration

A1A clearance >50 mL/24 hours suggests protein-losing enteropathy.
colonoscopy if preliminary test unrevealing; to exclude inflammatory bowel disease; microscopic colitis; CMV in immune-suppressed
additional testing, see American Gastroenterological Association guidelines for diarrhea evaluation

Chronic diarrhea evaluation hospitalized for 3 days or more

evaluation similar to those hospitalized less than 3 days
to also consider serum AM cortisol to assess for adrenal insufficiency

General complications of diarrhea

Dehydration (manifested as tachycardia and/or hypotension)
Serum electrolyte imbalances
Metabolic acidosis
Malnutrition
Skin breakdown

General Management

avoidance of malnutrition
fluid resuscitation
electrolyte resuscitation (potassium, magnesium, zinc)
treating underlying source for diarrhea
anti-diarrheal in the absence of bloody diarrhea, abdominal pain and fever

Emergency Management

Emergent complications of diarrhea

Toxic megacolon is a surgical emergency due to the high risk of perforation.
Hemolytic uremic syndrome (complication of E. coli 0157)
Intestinal ischemia
Sepsis

Management

Toxic megacolon

NPO

NGT

fluid and electrolyte repletion

discontinue antimotility medications: i.e. narcotics, anti-diarrheals, anti-cholinergics.

surgery consultation

consideration for systemic antibiotics

Hemolytic uremic syndrome

volume expansion with isotonic saline or Ringer’s lactate

transfuse for symptomatic anemia

transfuse platelets if clinically significant bleeding or invasive procedure needed

close monitoring: urine output, weight, volume status, cardiovascular function, respiratory function, and early signs of CNS compromise

nephrology consultation; indication for dialysis the same as for acute renal failure; to consider plasmapheresis but unclear benefit

Intestinal ischemia

imaging (i.e. CT) to assess location (i.e. small intestine, colon)

follow abdominal exam for signs of worsening tenderness, peritoneal signs

follow labs for metabolic acidosis, rise in serum lactate

consultation: surgery to follow, may need gastroenterology to aid/verify diagnosis (i.e. flexible sigmoidoscopy)

Sepsis

see other chapters for general management of sepsis in the ICU

blood cultures

antibiotics, best if specific to organism suspected

aggressive volume repletion

may need vasopressors

Treatment and prevention

Empiric therapy with loperamide or diphenoxylate may help minimize volume loss. Adsorbents (bismuth subsalicylate [Pepto-Bismol], dioctahedral smectite, attapulgite [Kaopectate]), tincture of opium, and codeine can also be used in refractory cases. Antidiarrheal medications are not recommended in the setting of fever or bloody diarrhea. Absorbents should be avoided if oral antibiotics are given, since absorbents may interfere with antibiotic absorption.

Special considerations:

Noninfectious causes

Enteral feeding : if bolus or gravity feeding, consider changing to continuous, and if other causes have been excluded, consider changing enteral feed composition, rate, consider adding fiber

Intestinal ischemia: if related to hypotension may be able to be managed conservatively, consult surgery and gastroenterology services

Bacterial overgrowth: once diagnosed; treatment with antibiotics (i.e. rifaximin, metronidazole)
Infections

Clostridium difficile: 1) Vancomycin 125 mg PO or per enteral tube every 6 hours x 10 days or metronidazole 250 mg PO or per enteral tube every 6 hours x 10 days. 2) Severe cases (serum albumin <3 g/dl and WBC ≥ 15,000 cells/mm³ or abdominal tenderness): vancomycin 125 mg PO or per enteral tube is preferred over metronidazole and 250 mg PO or per enteral tube may be used if concern for ileus. In severe cases vancomycin may also be combined with metronidazole IV or PO/per enteral tube. 3) Severe and complicated cases (any of the following due to Clostridium difficile infection: admission to the ICU, hypotension, fever ≥38.5°C, ileus or significant abdominal distention, mental status changes, WBC ≥ 35,000 cells/mm³ or <2,000 cells/mm³, serum lactate ≥2.2 mmol/l, end organ failure (mechanical ventilation, renal failure, etc.): vancomycin 500 mg PO or per enteral tube, metronidazole 500 mg IV every 8 hours and vancomycin 500 mg per rectal tube four times a day. Surgery consultation also recommended. 4) Surgery should be considered if any of the following caused by Clostridium difficile infection: hypotension requiring vasopressor therapy, clinical signs of sepsis or organ dysfunction; mental status changes; WBC ≥50,000 cells/mm³, lactate ≥5 mmol/l; or complicated CDI with failure to improve on medical therapy after 5 days. 5) Recurrent Clostridium difficile (within 8 weeks)- with 3^rd episode consider Vancomycin pulsed regimen, if recurrence after pulsed regimen consider FMT. 6)Avoid antibiotics that lead to Clostridium difficile diarrhea. If antibiotics are absolutely necessary then consider switching to antibiotics associated with less risk (i.e. avoiding fluoroquinolones, ampicillin, clindamycin and cephalosporins). 7) Contact precautions. 8) Probiotics are not yet recommended to prevent Clostridium difficile infection in the ICU.

Norovirus : 1) General management of diarrhea. 2) Contact precautions. 3) Resistance to alcohol and environment may need to be cleaned with bleach. 4) Employees involved in cleaning may benefit by wearing a mask because heavily soiled surfaces may lead to aerosolization.

Salmonella : usually self-limited; antibiotic therapy recommended for moderate to severe disease, bacteremia, signs of extraintestinal disease, patients with sickle cell disease or prosthetic grafts, and immune-suppressed patients. Levofloxacin 500 mg once a day for 7-10 days or azithromycin 500 mg once a day for 7 days.

Cryptosporidium : usually self-limited in immune-competent individuals; may use nitazoxanide 500 mg PO twice a day for 3days; HIV patients: unclear benefit of nitazoxanide, need to improve CD4 count

Special considerations for nursing and allied health professionals.

N/A

“AGA Technical Review on the Evaluation and Management of Chronic Diarrhea”. Gastroenterology. vol. 116. 1999. pp. 1464-86. (An extensive review on the diagnostic evaluation of chronic diarrhea released by the American Gastroenterological Association.)

Bitzan, M. “Treatment options for HUS secondary to Escherichia coli O157:H7”. Kidney international Supplement. vol. 112. 2009. pp. S62-6. (Current management recommendations for hemolytic uremic syndrome due to Escherichia coli O157:H7.)

Bobo, LD. “Recognition and prevention of hospital-associated enteric infection in the intensive care unit”. Crit Care Med. vol. 38. 2010. pp. S324-34. (An excellent overview of infectious diarrhea in the intensive care unit.)

Blaser, A. “Diarrhoea in the critically ill”. Cur Opin Crit Care. vol. 21. 2015. pp. 142-153. (Review focused on the evaluation of diarrhea in the intensive care unit.)

Pawlowski, SW. “Diagnosis and treatment of acute or persistent diarrhea”. Gastroenterology. vol. 136. 2009. pp. 1874-86. (An excellent review of infectious causes of acute and chronic diarrhea.)

Riddle, D. ” infection in the intensive care unit”. Infectious Disease Clinics of North America. vol. 23. 2009. pp. 727-43. (A comprehensive review of the epidemiology, pathophysiology, diagnostic evaluation and management of Clostridium difficile infection in the intensive care setting.)

Suracicz, C. “Guidelines for Diagnosis. Treatment and Prevention of Infections”. Am J Gastroenterol. vol. 108. 2013. pp. 478-498. (Guidelines from the American College of Gastroenterology for evaluation and management of Clostridium difficile infection.)

Zilberberg, M. “Preventing Infection in the Intensive Care Unit”. Crit Care Clin. vol. 29. 2013. pp. 11-18. (Review of the methods and supporting evidence for preventing Clostridium difficile infection in the Intensive Care Unit.)

No sponsor or advertiser has participated in, approved or paid for the content provided by Decision Support in Medicine LLC. The Licensed Content is the property of and copyrighted by DSM.

Jump to Section

Critical Care Medicine