How to manage hypotension in a patient with dengue fever?

Management of Hypotension in Dengue Fever

For dengue shock syndrome with hypotension, immediately administer 20 mL/kg of isotonic crystalloid (Ringer's lactate or 0.9% normal saline) as a rapid bolus over 5-10 minutes, with immediate reassessment after each bolus and readiness to repeat up to 40-60 mL/kg in the first hour before escalating to vasopressors. 1

Initial Fluid Resuscitation Protocol

Crystalloid resuscitation is first-line therapy and achieves near 100% survival when properly administered in dengue shock syndrome. 1

• Administer the initial 20 mL/kg bolus over 5-10 minutes using isotonic crystalloid (Ringer's lactate or 0.9% normal saline) 1, 2
• Reassess immediately after each bolus for signs of improvement: decreased tachycardia, decreased tachypnea, improved capillary refill, warming of extremities, improved mental status, and adequate urine output 1, 2
• If shock persists after the initial bolus, repeat crystalloid boluses up to a total of 40-60 mL/kg in the first hour 1, 2
• Delaying fluid resuscitation in established dengue shock syndrome significantly increases mortality, as cardiovascular collapse may rapidly follow once hypotension occurs 1

When to Escalate to Colloids

• Consider switching to colloid solutions (albumin, gelafundin, or dextran) if shock persists despite adequate crystalloid resuscitation or if pulse pressure is <10 mmHg 1, 3
• Moderate-quality evidence shows colloids achieve faster resolution of shock (RR 1.09,95% CI 1.00-1.19) and reduce total volume needed (mean 31.7 mL/kg versus 40.63 mL/kg for crystalloids) 1
• However, clinical outcomes (mortality) are similar between crystalloids and colloids when properly administered 1

Vasopressor Therapy for Refractory Shock

If shock persists despite 40-60 mL/kg of crystalloid in the first hour, switch strategy from aggressive fluid administration to inotropic support rather than continuing fluid boluses. 1, 2

• For cold shock (poor perfusion, cold extremities) with hypotension: titrate epinephrine as first-line vasopressor 1, 2
• For warm shock (bounding pulses, warm extremities) with hypotension: titrate norepinephrine as first-line vasopressor 4, 1, 2
• Target mean arterial pressure appropriate for age and maintain ScvO2 >70% 1
• Begin peripheral inotropic support immediately if central venous access is not readily available, as delays in vasopressor therapy are associated with major increases in mortality 1

Critical Monitoring Parameters During Resuscitation

• Watch for signs of adequate tissue perfusion: normal capillary refill time (<2 seconds), absence of skin mottling, warm and dry extremities, well-felt peripheral pulses, return to baseline mental status, and adequate urine output (>0.5 mL/kg/hour in adults) 1, 2
• Monitor hematocrit closely: rising hematocrit indicates ongoing plasma leakage and need for continued resuscitation, while falling hematocrit suggests successful plasma expansion 1, 2
• Stop fluid resuscitation immediately if signs of fluid overload develop: hepatomegaly, pulmonary rales, or respiratory distress 1, 5

Critical Pitfalls to Avoid

• Do NOT give routine bolus IV fluids to patients with dengue fever who are NOT in shock - this increases fluid overload and respiratory complications without improving outcomes 1, 6
• Do NOT continue aggressive fluid resuscitation once signs of fluid overload appear - switch to inotropic support instead 1, 2
• Do NOT use restrictive fluid strategies in established dengue shock syndrome - moderate-quality evidence shows no survival benefit from colloid restriction, and aggressive fluid management achieves near 100% survival 1
• Do NOT delay vasopressor initiation if shock persists despite adequate fluid resuscitation - delays are associated with major increases in mortality 1
• Blood pressure alone is not a reliable endpoint in children, as hypotension is a late finding 1

Special Considerations

• Myocardial dysfunction may contribute to persistent hypotension in some patients despite adequate hydration - consider echocardiography if hypotension persists despite appropriate fluid resuscitation 7
• In resource-rich settings with persistent shock, consider invasive monitoring (central venous pressure, arterial line) to guide therapy 1
• After initial shock reversal, judicious fluid removal may be necessary during the recovery phase - evidence shows that aggressive shock management followed by fluid removal decreased pediatric ICU mortality from 16.6% to 6.3% 1
• Consider continuous renal replacement therapy (CRRT) if fluid overload >10% develops, as outcomes are better when CRRT is initiated early 1

Supportive Care

• Use acetaminophen only for pain and fever management - never use aspirin or NSAIDs due to increased bleeding risk 1, 3, 2
• Blood transfusion may be necessary for significant bleeding - target hemoglobin >10 g/dL if ScvO2 <70% 1, 2
• Maintain adequate oxygenation and consider higher packed cell volume targets to ensure adequate tissue perfusion during shock 8