What is dengue investigation Management

1. Management Of Dengue

3. Dengue Virus
• The dengue viruses are the members of the genus flavivirus. These small
(50nm)viruses contain single stranded RNA.
• There are four virus serotypes, which are designated as DEN-1, DEN-2,
DEN-3 and DEN-4.
• Although all four serotypes are antigenicaly similar, they have envelop
proteins that have epitopes unique to the serotype

4. Vector
• Dengue is transmitted by the bite of female Aedes mosquito
• The eggs can survive one year without water. At low temperature,
however, it may take several weeks to emerge. Ae. aegypti has an average
adult survival of fifteen days.
• They breed in artificial containers of water.
• During the rainy season, when survival is longer, the risk of virus
transmission is greater. It is a day time feeder and can fly up to a limited
distance of 400 meters.
• To get one full blood meal the mosquito has to feed on several persons,
infecting all of them.

6. Clinical Features
Patients with dengue infection can be classified as follows :
• Asymptomatic
• Undifferentiated Fever
• Dengue without warning Signs
• Dengue with warning signs
• Severe Dengure

7. Dengue Fever
Febrile phase
• Sudden onset high grade fever, 2-7 days.
• Associated flushing, skin erythema, generalized body ache, myalgia, arthralgia, anorexia,
nausea, and vomiting, retrobulbar pain may be present.
• Minor haemorrhagic manifestations such as petichae and muscosal bleed might be present.
• Liver maybe enlarged 2-5 days (indicates risk for severe disease)
Critical phase
• Between 3-7 days of onset of fever
• Bleeding, shock
• Some children develop organ failure : severe hepatitis, encephalitis or myocarditis
Recovery phase
• Some experience generalized pruritus, rash(iles of white in a sea of red), bradycardia and
respiratory depression

8. Laboratory Investigation
• Blood reports
o Increaing packed cell volume
o Low platelet count
o Decreasing leukocyte (DD malaria typhoid/paratyphoid) count with increasing lymphocytes
o Decrease in total proteins and albumin
o SGOT & SGPT levels raised
o Severe cases – hyponatremia, acidosis, raised urea and creatinine levels might be seen.
• X ray : varying degrees of pleural effusion
• Ultrasonography : ascites and enlarged gall bladder.

9. Confirmatory tests
• Direct Methods :
– Isolation by culture
– Genome detection by PCR (First 5
days, expensive)
– NSI antigen detection (Preferably
for first 8 days, highly sensitive
in first 4 days – 100%)
– Antibody determination ( IgM in
day 5 in 80% and in 99% by day
10 and disappear in 2-3 months;
IgG rise later and remain
through out life)

10. Management

11. Criteria for hospitalisation
Indication for hospitalisation
Dengue with warning signs.
• Severe intense abdominal pain, clinical fluid accumulation
• Persistent vomiting, mucosal bleed
• Restlessness, lethargy, raise in HCT with rapid fall in platelet
count
Indication for ICU admission
Severe Dengue
• Shock
• Respiratory Distress
• Abdominal Bleeding
• Organ Failure eg. Neurological complication, liver or renal
dysfunction

12. 1. Undifferentiated fever
Signs & Symptoms: Non-specific symptoms and signs.
Treatment :
a. Paracetamol
b. Regular monitoring of BP and look for warning signs

13. 2. Dengue infection without warning signs
Signs & Symptoms: Fever, body aches, rashes or minor bleeds
Treatment :
a. Paracetamol
b. Regular monitoring of BP, look for warning signs along
with platelet counts and haematocrit.
c. Encourage child to drink plenty of fluids
Note : Avoid salicylates and other NSAIDs

14. 2. Dengue infection with warning signs
Warning signs :
(i) Abdominal pain or tenderness
(ii) Persistent Vomiting
(iii)Clinical fluid accumulation
(iv)Mucosal bleed
(v) Lethargy, restlessness
(vi)Liver enlargement >2cm
(vii)Laboratory features – rapid decrease of platelet count (≤
1,00,000) and increase in packed cell volume (≤ 20%).

15. Dengue fever with risk factors Hospitalise Ringer lactate (RL) 7ml/kg/hr
Assessment at one hr; vitals and haematocrit
No improvement
RL 10ml/kg/hr
Assessment at 2 hr
RL 15ml/kg/hr
Assessment at 3 hr
No improvement
Colloids 10ml/kg/hr No improvement Look for anaemia, acidosis and myocardial
dysfunction and treat accordingly
Improvement
RL 5 ml/kg/hr
Improvement
RL 3 ml/kg/hr
Continue IV fluids until stable for 24hr.
Discharge when stable for 24-48 hours

16. 2. Severe Dengue infection
Children presenting with the following:
(i) Severe plasma leakage leading to
a. Shock (Hypotension, tachycardia, narrow pulse
pressure ≤ 20 mmHg and signs of poor
perfusion – cold extremities)
b. Fluid accumulation with respiratory distress
(ii) Severe bleeding
(iii)Severe organ involvement
a. Liver : AST or ALT ≥ 1000 IU/L
b. CNS : Impaired consciousness
c. Heart and other organ involvement

17. Severe dengue fever Assessment of shock
Hypotension
DSS III
RL 10 – 20 ml/kg/hr
Unrecordable blood pressure
DSS IV
RL 20 ml/kg/hr bolus; upto 3 bolusesAssessment
Gradually decrease
ringer lactate
infusion
No improvementImproved
Haematocrit decreasedHaematocrit increased
Colloids 10ml/kg Blood transfusion
Assessment
Improved No improvement
Look for anaemia, acidosis and myocardial dysfunction and treat accordingly

18. End point of fluid administration
• Minimal urine output of 0.8 – 1 ml/kg/hr is a valuable end point
• Acceptable mean pressure
• Normalisation of pulse pressure
• Fall in haematocrit to approximately 20% of admission values

19. Approach for severe dengue
and refractory shock

20. Stabilise ABC, 6% hetastarch/gelatin 10-20 ml/kg as 2-3 boluses over 15-30 mins. Correct hypoglycaemia,
hypocalcaemia acidosis. Monitor haemodynamic. Vitals, clinical indices of perfusion, hourly urine output,
2-4 hourly HCT, transfuse fresh whole blood/PRBC if hypotension still persists.
Evaluate for unrecognised morbidities.
Consider PRBC, inotrope/pressor depending on SBP, Consider ECHO
Consider CVP with great care if expertise is availableCVP low/ HCT high
Consider inotrope/vasopressor depending on SBP
• Dopamine/ adrenaline (SBP low)
• Dobutamine (SBP normal/high)
Discontinue inotropes if tachycardia or shock worsens.
ECHO for LV/RV systolic and diastolic function assess filling
Check IAP. Controlled ascetic fluid drainage with
great caution if IAP elevated and shock refractory
Titrate crystalloids/ colloids
till CVP target
Respiratory distress
Consider ventilation/ nasal CPAP, infuse
fluids till CVP/HCT target. Consider
inotropes/vasopressor depending on SBP,
serial ECHO and clinical response

21. Haemodynamic
improved
Haemodynamics
unstable
Wean ventilation and
inotrope/pressor. Taper
fluids gradually.
Check IAP. Controlled ascetic fluid drainage with
great caution if IAP elevated and shock refractory

22. Management of bleeding
A. Petechial spots or mild mucosal bleeds but haemodynamically stable :
Supportive care, hydration and monitoring
B. Severe bleed and haemodynamic instability, excessive mucosal bleed:
Blood transfusion and monitoring
Note :
• There is little evidence for transfusion of fresh frozen plasma or platelet concentrate
for severe bleeding.
• When bleeding cannot be managed with fresh blood, consider possibility of DIC. In
such cases fresh frozen plasma or platelet rich plasma may be considered.

23. Monitoring
Heart rate, respiratory rate, blood pressure and pulse pressure
needs to be monitored
In unstable patients every 30mins till the patient is stable.
Haematocrit measured every Q 2-4th hourly in unstable patients
for the first 12hrs then Q 6-8th hourly
There after every 2-4 hours as long as the child is in the hospital.
In severely critical cases central venous pressure and urinary
output should be measured.

24. Other supportive therapies
• Correction of electrolytes and acidosis : hypoglycaemia,
metabolic acidosis, hyponatraemia and hypocalcaemia.
• Sedatives : Chloral hydrate maybe preferred
• Antibiotics : not indicated unless co-infections suspected
• Oxygen therapy : All children in shock should be given oxygen in
the highest concentration in the least invasive as possible

25. Criteria for discharge
• Return of appetite
• Clinical improvement
• Good urine output
• Stable haematocrit
• 2 days after recovery from shock
• No respiratory distress from pleural effusion and ascites.