What is the initial management for a patient presenting with diarrhea?

Initial Triage and Management of Acute Diarrhea

The initial management of diarrhea centers on rapid assessment of hydration status and immediate rehydration with oral rehydration solution (ORS) for mild-to-moderate dehydration, reserving intravenous fluids only for severe dehydration, shock, or altered mental status. 1

Immediate Assessment: Determine Hydration Status

Assess dehydration severity using these specific clinical signs:

• Mild dehydration (3-5% fluid deficit): Slightly dry mucous membranes, increased thirst, slightly decreased urine output 1

• Moderate dehydration (6-9% fluid deficit): Sunken eyes, decreased skin turgor (skin pinch retracts slowly), dry mucous membranes, lethargy 1

• Severe dehydration (≥10% fluid deficit): Severe lethargy or altered consciousness, prolonged skin tenting (>2 seconds), cool and poorly perfused extremities, decreased capillary refill, rapid deep breathing (acidosis), weak or absent pulse 1

Note: Rapid deep breathing, prolonged skin retraction, and decreased perfusion are more reliable predictors of dehydration than sunken fontanelle or absent tears 1

Rehydration Protocol Based on Severity

Mild Dehydration (3-5% deficit)

• Administer 50 mL/kg of reduced osmolarity ORS over 2-4 hours 1, 2
• Start with small volumes (one teaspoon) using a syringe or dropper, gradually increasing as tolerated 1
• Reassess hydration status after 2-4 hours 1

Moderate Dehydration (6-9% deficit)

• Administer 100 mL/kg of ORS over 2-4 hours 1, 2
• Use same gradual administration technique as mild dehydration 1
• Consider nasogastric ORS if patient cannot tolerate oral intake but has normal mental status 1

Severe Dehydration (≥10% deficit)

• This is a medical emergency requiring immediate IV rehydration 1
• Administer 20 mL/kg boluses of lactated Ringer's or normal saline until pulse, perfusion, and mental status normalize 1
• May require two IV lines or alternate access (venous cutdown, femoral vein, intraosseous) 1
• Once mental status normalizes, switch to ORS for remaining deficit 1

No Dehydration

• Skip rehydration phase and proceed directly to maintenance therapy 1

Replace Ongoing Losses

During both rehydration and maintenance phases:

• Administer 10 mL/kg of ORS for each watery stool 1, 2
• Administer 2 mL/kg of ORS for each vomiting episode 1, 2

Nutrition Management

• Continue breastfeeding throughout the illness without interruption 1, 2
• Resume age-appropriate normal diet immediately after rehydration is complete 1, 2
• Do not withhold food or use diluted formulas 1

Medication Decisions

Antimotility Agents

• Loperamide is absolutely contraindicated in all children <18 years of age 1, 2, 3
• In adults, loperamide may be used for watery diarrhea ONLY 1
• Avoid loperamide at any age if fever present, bloody diarrhea, or suspected inflammatory diarrhea (risk of toxic megacolon) 1

Antiemetics

• Ondansetron may be given to children >4 years old to facilitate oral rehydration if vomiting is severe 1, 2

Antibiotics

• Do NOT give empiric antibiotics for acute watery diarrhea without recent international travel 1
• Exception: immunocompromised patients or ill-appearing young infants 1

When to Order Diagnostic Testing

Laboratory workup and stool cultures are NOT needed for routine acute watery diarrhea. 1, 4

Order diagnostic tests ONLY when:

• Severe dehydration present 4
• Bloody stools (dysentery) 1, 4
• Persistent fever 4
• Immunosuppression or immunosuppressive therapy 1, 4
• Suspected nosocomial infection or outbreak 4
• Symptoms persist >14 days 1

Measure serum electrolytes only when clinical signs suggest abnormal sodium or potassium concentrations 1

Red Flags Requiring Urgent Referral

Refer immediately to gastroenterology or emergency department if:

• Unable to tolerate oral fluids despite attempts 2
• Signs of worsening dehydration 2
• Bloody diarrhea develops 2, 5
• Significant fever increase 2
• Weight loss with chronic symptoms 5
• Palpable abdominal mass 5
• Clinical or laboratory signs of anemia 5

Common Pitfalls to Avoid

• Do not use apple juice, Gatorade, or commercial soft drinks for rehydration—these lack appropriate sodium content and osmolarity 1
• Do not give antimotility drugs to children under any circumstances 1, 2
• Do not routinely order stool cultures for uncomplicated watery diarrhea 1
• Do not prescribe empiric antibiotics for typical acute watery diarrhea 1