2. Most rapidly spreading arthropod-borne viral
disease of the world
All-year round disease in the Philippines
high incidence during rainy months and is
more prevalent in urban areas
3. VIRUS
• Dengue virus (DEN)- small single stranded
RNA virus
• Has 4 distinct serotypes (DEN- 1 to 4)
• “Asian” genotypes of DEN-2 and DEN-3 are
frequently associated with severe disease
accompanying dengue infections
4. VECTOR
• Family of Flaviviridae
• 1) female Aedes aegypti mosquito
2) Aedes albopictus
• generally “daybiters” with 2 peaks of
biting time:
a) at dawn, just before sunrise
b) at dusk, just before sunset
5. VECTOR
• Resting habit:
1. Aedes aegypti - cool, dark corners
of the house
2. Aedes albopictus - outdoors in
clearing vegetations
• Flying habits:
- average light range is 50 meters
- farthest distance is only within 200-
400 meter radius from breeding
places
6. HOST
• incubation period of 4-10 days
• Primary infection:
• is thought to induce lifelong protective immunity
to the infecting serotype
• Individuals suffering an infection are protected
from clinical illness with a different serotype
within 2-3 months of the primary infection but
with no long-term cross-protective immunity
7. HOST
• virus enters via the skin while an infected
mosquito is taking a bloodmeal
• acute phase of illness- the virus is present in
the blood
• Defervescence- clearance of the virus from
the blood
8. HOST
• Humans- main amplifying host of the virus
• Dengue virus circulating in the blood of
viraemic humans is ingested by female
mosquitoes during feeding
• The virus then infects the mosquito mid-gut
and subsequently spreads systemically over a
period of 8-12 days (extrinsic incubation)
9. HOST
• the virus can be transmitted to other humans
during subsequent probing or feeding
11. 1. Increased capillary fragility
• Early febrile stage
• (+) tourniquet test
• Hemorrhagic tendencies of a patient
12. 2. Thrombocytopenia
• may be associated with alterations in
megakaryocytopoieses by the infection of
human haematopoietic cells and impaired
progenitor cell growth
• Which results in platelet dysfunction (platelet
activation and aggregation) and increased
destruction or consumption (peripheral
sequestration and consumption).
13. 3. Decreased blood coagulation factors
• Fibrinogen and factors II, V, VII, IX
• Prolonged CT-BT, PT, PTT
14. Incubation period of 4-10 days
3 phases of the disease
◦ FEBRILE
◦ CRITICAL
◦ RECOVERY PHASE
15.
16. Usually lasts 2–7 days
Sudden high-grade fever
facial flushing, skin erythema, generalized
body ache, myalgia, arthralgia, headache,
sore throat, injected pharynx, conjunctival
injection, anorexia, nausea and vomiting are
common
17. Mild hemorrhagic manifestations
- Petechiae
- Mucosal membrane bleeding
liver is often enlarged and tender after a few
days of fever
Earliest manifestation in CBC:
- Progressive increase in WBC
18. Marks the beginning of
the critical phase:
• Usually on day 3-7 of the
illness
• increase in capillary permeability in parallel with
increasing haematocrit levels
• temperature has dropped to less than 37.5- 38 C
and remains below this level
The period of clinically significant plasma
leakage usually lasts 24–48 hours
19. Progressive leukopenia followed by a rapid
decrease in platelet count usually precedes
plasma leakage
Without an increase in capillary
permeability improve Dengue without
warning signs
With increased capillary permeability
deteriorate (result of lost plasma volume)
Dengue with warning signs
20. Shock- occurs when a critical volume of
plasma is lost through leakage; further
deterioration
◦ Often preceded by warning signs
Warning Signs
Abdominal pain or tenderness
Persistent vomiting
Clinical signs of fluid accumulation
Mucosal bleeding
Lethargy; restlessness
Liver enlargement
Labs: ↑ in hematocrit and/or ↓ platelet
21. takes place in the following
48–72 hours after
critical phase
What happens in recovery phase?
◦ a gradual reabsorption of extravascular
compartment fluid
◦ General well-being improves
◦ appetite returns
◦ gastrointestinal symptoms abate
◦ haemodynamic status stabilizes
◦ diuresis ensues
22. Hermann’s rash- “isles of white in the sea of
red”
The haematocrit stabilizes or may be lower
due to the dilutional effect of reabsorbed
fluid
White blood cell count usually starts to rise
soon after defervescence while the recovery
of platelet count is typically later than that of
white blood cell count.
31. Probable dengue
◦ Lives in or travels to dengue-endemic area, with fever plus any of
the following:
Headache Nausea
Body malaise Vomiting
Myalgia Arthralgia
Retro-orbital pain Anorexia
Diarrhea Flushed skin
Rash (petechial, Hermann’s rash ) AND
CBC (leukopenia with or without thrombocypenia) and/or
dengue NS1 antigen test or dengue IgM antibody test
Confirmed: viral culture isolation and PCR
32. Lives in or travels to dengue-endemic area,
with fever lasting for 2-7days, plus any one
of the following:
Confirmed: viral culture isolation and PCR
Warning Signs
Abdominal pain or tenderness
Persistent vomiting
Clinical signs of fluid accumulation
Mucosal bleeding
Lethargy; restlessness
Liver enlargement
Labs: ↑ in hematocrit and/or ↓ platelet
33. Lives in or travels to a dengue-endemic area
with fever of 2-7 days, and any of the above
clinical manifestation for dengue
with/without warning signs plus any of the ff:
◦ Severe plasma leakage
Shock
Fluid accumulation with respiratory distress
◦ Severe bleeding
◦ Severe organ impairment
Liver: AST or ALT >/= 1000
CNS: e.g. seizure, impaired consciousness
Heart: e.g. myocarditis
Kidneys: e.g. renal failure
34. Step 1: Overall Assessment
◦ History
◦ Physical Examination
◦ Investigation
Step 2: Diagnosis, Assessment of Disease
Phase and Severity
Step 3: Management
◦ Group A
◦ Group B
◦ Group C
35. Treatment (by type of patient)
GROUP A- Patients who may be sent home
- Able to tolerate adequate volumes of oral
fluids
- Able to pass urine at least once every 6 hours
- Do not have any warning signs particularly
when fever subsides
36. What should be done?
◦ Adequate bed rest
◦ Adequate fluid intake
◦ Paracetamol
◦ Tepid sponging
◦ Look for mosquito breeding places and eliminate
them
What shoud be avoided?
◦ NSAIDs
◦ Antibiotics are unecessary
37. If any of the ff is observed, take immediately
to nearest hospital:
◦ Bleeding,vomiting, abdominal pain, drowsiness,
pale, cold and clammy hands and feet, difficulty in
breathing
38. Warning signs
Co-existing conditions that may make
dengue management more complicated such
as pregnancy, infancy, and old age, obesity,
diabetes mellitus, renal failure, chronic
hemolytic diseases, etc
Social circumstances such as living alone or
living far from health facility or without a
reliable means of transport
40. Dengue without warning signs
Monitor for the ff:
◦ Temperature pattern
◦ Volume of fluid intake and losses
◦ Urine output- volume and frequency
◦ Warning signs
◦ Hematocrit
◦ White blood cells
◦ Platelets
41. Dengue with warning signs
1. Obtain a reference hematocrit
1. Give only isotonic solutions
- Start with 5-7ml/kg/hour for 1-2 hours, then
- Reduce to 3-5ml/kg/hour for 2-4 hours, and then
- Reduce to 2-3 ml/kg/hour or less according to clinical
response
2. Reassess clinical status and repeat
hematocrit
42. Dengue with warning signs
4. If Hct remains the same or rises only minimally,
continue with the same rate (2-3 ml/kg/hour)
for another 2-4 hours
5. If there are worsening vital signs and rapidly
rising hematocrit, increase the rate to 5-10
ml/kg/hour for 1-2 hours
6. Reassess clinical status, repeat hematocrit and
review fluid infusion rates accordingly
43. Dengue with warning signs
7. Reduce intravenous fluids gradually when the
rate of plasma leakage decreases towards the
end of the critical phase.
- urine output and/or oral fluid is/are adequate
or
- hematocrit decreases below the baseline value
in stable patient
44. Dengue with warning signs
should be monitored by health care providers
until the period of risk is over
A detailed fluid balance should be maintained
Parameters that should be monitored include
vital signs and peripheral perfusion, urine
output, haematocrit, blood glucose, and
other organ functions
45. severe plasma leakage leading to dengue
shock and/or fluid accumulation with
respiratory distress
severe haemorrhages
severe organ impairment (hepatic damage,
renal impairment, cardiomyopathy,
encephalopathy or encephalitis)
46. Patients with Compensated Shock
1. Start IVF resuscitation with isotonic fluid at 5-10
ml/kg/hr over 1 hour. Reassess patient’s
condition and decide depending on the situation
2. If the patient’s condition improves, intravenous
fluids should be gradually reduced to:
- 5-7 ml/kg/hr for 1-2 hours, then
- to 3-5 ml/kg/hr for 2-4 hours, then
- to 2-3 ml/kg/hr and then
- to reduce further depending on the hemodynamic status of
the patient, which can be maintained for up to 24-48 hours
47. Patients with Compensated Shock
3. If the vital signs are still unstable, check
hematocrit after the first bolus:
- if Hct increases or still high (>50%) ,
repeat a 2nd bolus of crystalloid solution at
10ml/kg/hr for 1 hour . After this 2nd bolus,
of there is improvement, then reduce the
rate to 7-10ml/kg/hr for 1-2 hours, then
continue to reduce as above
48. Patients with Compensated Shock
if hct decreases compared to the intial
reference hematocrit, this indicates
bleeding and the need to cross match and
transfuse blood as soon as possible
49.
50. Patients with Hypotensive Shock
Patients with hypotensive shock should be
managed more vigorously
1. Initiate intravenous fluid resuscitation with
crystalloid or colloid solution (if available) at
20 ml/kg as a bolus given over 15 minutes to
bring the patient out of shock as quickly as
possible
51. Patients with Hypotensive Shock
2. If the patient’s condition improves, give a
crystalloid/colloid infusion of 10 ml/kg/hr for
one hour. Then continue with crystalloid
infusion and gradually reduce to 5–7ml/kg/hr
for 1–2 hours, then to 3–5 ml/kg/hr for 2–4
hours, and then to 2–3 ml/kg/hr or less,
which can be maintained for up to 24–48
hours
52. Patients with Hypotensive Shock
3. If vital signs are still unstable (i.e. shock
persists), review the haematocrit obtained
before the first bolus. If the haematocrit was
low (<40% in children and adult females, <45%
in adult males), this indicates bleeding and the
need to crossmatch and transfuse blood as
soon as possible
53. Patients with Hypotensive Shock
4. If the haematocrit was high compared to the
baseline value, change intravenous fluids to colloid
solutions at 10–20 ml/kg as a second bolus over
30 minutes to one hour. After the second bolus,
reassess the patient. If the condition improves,
reduce the rate to 7–10 ml/kg/hr for 1–2 hours,
then change back to crystalloid solution and reduce
the rate of infusion as mentioned above. If the
condition is still unstable, repeat the haematocrit
after the second bolus.
54. Patients with Hypotensive Shock
5. If the haematocrit decreases compared to
the previous value this indicates bleeding
and the need to cross-match and transfuse
blood as soon as possible
55. Patients with Hypotensive Shock
6. If the haematocrit increases compared to
the previous value or remains very high
(>50%), continue colloid solutions at 10–20
ml/kg as a third bolus over one hour. After
this dose, reduce the rate to 7–10 ml/kg/hr
for 1–2 hours, then change back to
crystalloid solution and reduce the rate of
infusion as mentioned above when the
patient’s condition improves
56. Patients with Hypotensive Shock
7. Further boluses of fluids may need to be
given during the next 24 hours. The rate
and volume of each bolus infusion should
be titrated to the clinical response. Patients
with severe dengue should be admitted to
the high-dependency or intensive care area
57.
58.
59. Mucosal bleeding
Profound thrombocytopenia- ensure strict
bedrest and protection from trauma to reduce
the risk of bleeding
No IM injections
If major bleeding occurs- usu from GIT or per
vagina in females; internal bleeding- may not
become apparent for many hours until the
first black stool is passed
60. Who are at risk for bleeding?
◦ prolonged or refractory shock
◦ hypotensive shock and renal or liver failure and or
severe metabolic acidosis
◦ given with NSAIDs
◦ existing peptic ulcer disease
◦ on anticoagulant therapy
◦ any form of trauma, including IM injections
61. How do you recognize severe bleeding?
◦ Persistent or severe/overt bleeding in the presence
of unstable hemodynamic status, regardless of the
hematocrit level
◦ A decrease in hematocrit after fluid resuscitation
together with unstable vital signs
◦ Refractory shock that fail to respond to consecutive
fluid resuscitation of 40-60ml/kg
62. ◦ Hypotensive shock with low/normal hematocrit
before fluid resuscitation
◦ Persistent or worsening met.acidosis +/- well
maintained SBP esp. in those with severe abdominal
tenderness and distention.
63. ACTION PLAN
Give 5–10ml/kg of fresh-packed red cells or
10–20 ml/kg of fresh whole blood at an
appropriate rate and observe the clinical
response. It is important that
A good clinical response includes improving
haemodynamic status and acid-base balance
64. ACTION PLAN
Consider repeating the blood transfusion if
there is further blood loss or no appropriate
rise in haematocrit after blood transfusion
Great care should be taken when inserting a
naso-gastric tube which may cause severe
haemorrhage and may block the airway. It
should be lubricated.
65. ACTION PLAN
Insertion of central venous catheters should
be done with ultra-sound guidance or by a
very experienced person.
66. Causes of fluid overload are
– excessive and/or too rapid intravenous
fluids
– incorrect use of hypotonic rather than
isotonic crystalloid solutions
– inappropriate use of large volumes of
intravenous fluids in patients with
unrecognized severe bleeding
67. – inappropriate transfusion of fresh-frozen
plasma, platelet concentrates and
cryoprecipitates
– continuation of intravenous fluids after
plasma leakage has resolved (24–48 hours
from defervescence);
– co-morbid conditions such as congenital or
ischaemic heart disease, chronic lung and
renal diseases.
68. Early clinical features of fluid overload are:
– respiratory distress, difficulty in breathing
– rapid breathing
– chest wall in-drawing
– wheezing (rather than crepitations)
– large pleural effusions
– tense ascites
– increased jugular venous pressure (JVP)
69. Late clinical features are:
– pulmonary oedema (cough with pink or
frothy sputum ± crepitations, cyanosis)
– irreversible shock (heart failure, often in
combination with ongoing hypovolaemia)
70. ACTION PLAN
Oxygen therapy should be given immediately
Stopping intravenous fluid therapy during the
recovery phase will allow fluid in the pleural and
peritoneal cavities to return to the intravascular
compartment
71. ACTION PLAN
If the patient has stable haemodynamic status and
is out of the critical phase (> 24–48 hours of
defervescence), stop intravenous fluids but
continue close monitoring. If necessary, give oral
or intravenous furosemide 0.1–0.5 mg/kg/dose
once or twice daily, or a continuous infusion of
furosemide 0.1 mg/kg/hour
Monitor serum potassium and correct the ensuing
hypokalaemia
72. ACTION PLAN
If the patient has stable haemodynamic status but
is still within the critical phase, reduce the
intravenous fluid accordingly. Avoid diuretics
during the plasma leakage phase because they may
lead to intravascular volume depletion
73. ACTION PLAN
Patients who remain in shock with low or normal
haematocrit levels but show signs of fluid overload
may have occult haemorrhage
Careful fresh whole blood transfusion should be
initiated as soon as possible
If the patient remains in shock and the haematocrit
is elevated, repeated small boluses of a colloid
solution may help
74. Based on 7 Parameters
1. mental status
2. heart rate
3. blood pressure
4. respiratory rate
5. capillary refill time
6. peripheral blood volume
7. extremities
75. All of the following conditions must be present:
Clinical
- No fever for 48 hours
- Improvement in clinical status
Labortory
- Increasing trend of the platelet count
- Stable hematocrit without IVF
