6. Severe Dengue in ICU

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Severe Dengue in Intensive Care

The ICU Rule

Obstetric patients

Asthmatic patients

Dengue patients

MUST ADMIT

Dr Tai Li Ling

Because they shouldn’t DIE !!!

The management of DHF/ DSS in the intensive care unit (ICU) follows the general principles of management of any critically ill patient in the ICU.

Intensive Care Management

Severe Dengue

• Severe plasma leakage that may lead to shock and/ or fluid accumulation with or without respiratory distress

• Severe bleeding

• Severe organ involvement

1. Recurrent or persistent shock

2. Requirement for respiratory support

(non-invasive and invasive ventilation)

3. Significant bleeding

4. Encephalopathy or encephalitis

Indications for Referral to Intensive Care:

“ The key to success is

frequent monitoring and changing strategies

depending on clinical and laboratory evaluations.”

RECOGNIZE AND TREAT

Experts from India

1st Indication :Dengue Shock Syndrome • Early recognition and treatment of shock is essential

• Early referral

• ALL Grade 3 and Grade 4 DHF should be referred to ICU

• Management of DSS is a medical emergency and requires prompt and adequate fluid replacement

• Early and effective replacement of plasma losses results in a favorable outcome

Oxygen therapy should be given to ALL

patients in shock

Main objectives of respiratory support

• support pulmonary gas exchange

• reduce the metabolic cost of breathing

Indications for respiratory support

( invasive and non-invasive)

Reduces work of breathing & O2 consumption Improves oxygen delivery to tissues and allows

redistribution of blood flow to vital organs.

In general, respiratory support should be considered EARLY in a patient’s course of illness.

The decision to initiate respiratory support should be based on clinical judgement that considers the entire clinical situation.

1. Respiratory Failure – poor gas exchange Time frame of plasma leakage

In late phase of plasma leakage, respiratory distress may be compounded by pleural effusion, ascites

acute pulmonary oedema in late phase of leakage or resorption phase

2. Metabolic acidosis – work of breathing In early phase of plasma leakage, metabolic

acidosis is secondary to tissue hypoperfusion. Appropriate management is fluid

resuscitation and mechanical ventilation

In patients with metabolic acidosis, respiratory support should be considered despite the preservation of relatively normal arterial blood pH.

When to Intubate?

When to Intubate

• General principles of management applies• 3 main indications in dengue-

-Respiratory distress and fatigue due to excessive lung or pleural fluid accumulation/overload,

-Moderate to severe metabolic acidosis (decompensated shock).

-Hypoxic or dengue encephalopathy

Respiratory Distress and Fatigue

Recognize the decompensated patients :When PaCO2 is higher than expected to compensate for the acidosis, the patient should be promptly intubated.

Formula to calculate the expected

PaCO2 = 1.5 x [HCO3-] + 8±2 mmHg

RECOGNIZE AND TREAT

Severe metabolic acidosis is a late sign !

Severe shock is the result of inadequately treated plasma leakage ± bleeding.

Prolonged shock leads to metabolic acidosis and multi-organ dysfunction.

Lactic acidosis in DSS

Lactate ( Normal < 2 mmol/l) : end product of anaerobic glycolysis

1. An increase in blood lactate levels in patients who are haemodynamically unstable is taken as evidence of impaired oxygen utilization by cells / circulatory shock (Tissue hypoxia)

2. Liver failure

3. Encephalopathy

In patients with encephalopathy and

GCS of < 9 , intubation is often required

to protect the airway.

Neurological impairment: possible causes

Hypoxic encephalopathy Shock Hyponatraemia Metabolic acidosis Hepatic encephalopathy Dengue encephalitis Intracerebral bleed

Other Considerations in ICU

The Question of Vasopresors

In dengue, hypotension is usually due to plasma leakage or internal bleeding.

Fluid resuscitation is crucial and should be initiated first.

However, vasopressor (e.g. dopamine, noradrenaline) may be considered when a mean arterial pressure is persistently < 60 mmHg despite ADEQUATE fluid resuscitation.

During induction for intubation if hypotensive whilst still undergoing vigorous fluid resus

Indications for haemodynamic support

Inotropic and vasopressor support NOT the first line.

The Question of Invasive Tubings

1. Central venous catheter (CVC) insertion

No studies on dengue patients with regards to invasive procedures and bleeding risks.

Volume resuscitation does not require a CVC if sufficient peripheral intravenous access can be obtained (e.g. 14- or 16-gauge intravenous catheters).

Peripheral intravenous catheterisation may be preferable because a greater flow rate can be achieved.

Guide on safety and risk of invasive procedures

In general, thrombocytopaenia and other bleeding diathesis are relative contraindications to CVC placement.

High femoral, low internal jugular, and subclavian venous punctures are difficult to compress and confer an increased risk of uncontrolled bleeding.

Incidence of bleeding in patients with coagulopathy varies (0-15.5%).

Central venous catheter (CVC) insertion

• When CVC is indicated it should be inserted by a skilled

operator, preferably under ultrasound guidance if

available. • Subclavian vein cannulation should be avoided as far as

possible.

• Intra-arterial cannulation is useful as it enables

continuous arterial pressure monitoring and repeated

arterial blood gas sampling.

It has a very low incidence of bleeding (1.8 – 2.6%)

• An arterial catheter should be inserted in DSS patients

who require intensive monitoring and frequent blood

taking for investigations.

2. Arterial catheter insertion

If a gastric tube is required, the nasogastric route should be avoided.

Consider orogastric tube as this is less traumatic.

3. Gastric tube

Intercostal drainage of pleural effusions should be avoided as it can lead to severe haemorrhage and sudden circulatory collapse.

Intercostal drainage for pleural effusion is not indicated to relieve respiratory distress.

Mechanical ventilation should be considered.

4. Pleural tap and chest drain

Watch out for confounders

• Co morbid conditions– Congestive cardiac failure, valvular heart disease– Thyrotoxicosis– ESRF

• Pregnancy• Medications – beta blockers, anticoagulants

Take Home Messages

1. The management of severe dengue is a medical emergency and the key to success is frequent monitoring and changing strategies

2. Recognize the severe cases.

3. Early referral and PROMPT TRANSFER to intensive care.

4. Attend to patient on arrival

5. In ICU – BE VIGILANT. Early recognition and treatment of shock improves outcome.

6. Consider early respiratory support.

7. Metabolic acidosis is a late sign, don’t wait till patient collapses.

8. Inotropic and vasopressor support is not the answer to shock, prompt and adequate fluid replacement is.

9. CVP monitoring is not indicated

10. Avoid invasive procedures e.g. chest drain, ascitic drainage as they are hazardous.

Take Home Messages

6. Severe Dengue in ICU

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