2. Fluid Management in Dengue Hemorrhagic Fever Dengue Expert Advisory Group

Dengue Virus Infection Asymptomatic Symptomatic – Undifferentiated Febrile Illness – Dengue Fever – Dengue Hemorrhagic Fever  Non Shock  Shock

Dengue Hemorrhagic Fever Febrile Phase Critical phase characterized by plasma leak Convalescent Phase

Dengue “Leak” Fever Plasma leak during critical phase is the hall mark Leading to 3rd space losses – peritoneal cavity – pleural cavity Variable in magnitude and exact timing

Pathogenesis of leak Infection with a virulent dengue virus Presence of antibodies that enhance dengue virus infection (ADE) Intense immune activation

Pathogenesis Rapidly elevated cytokines (TNF-a, IL-2, IL-6, IL-8, IL-10, IL-12, and IFN-g) Malfunction of vascular endothelial cells Plasma leakage from intra to extravascular space

Pathogenesis In severe DHF the loss of plasma is critical Patient becomes hypovolaemic Signs of circulatory compromise Progress to shock, organ failure, death

Pathogenesis Cytokine Storm Self limited Ends after 48 hours

Clinical Implications Extravascular fluid loss at variable rate that has to be matched ml for ml Lasting 48 hours Resorption of fluid during convalescent phase

Key Points Manage critical phase with appropriate volume – Don’t under transfuse – Don’t over transfuse Meticulous monitoring during critical phase to match rate of fluid infusion with rate of leak

Monitoring Parameters Clinical – Pulse Rate – Blood and Pulse Pressure – Capillary Refill Time – Urinary Output Lab – Hematocrit

Fluid Management Critical Phase

Amount of Fluid? Based on weight Adults – If less than 50kg use actual weight – If more take weight as 50 kg Paediatrics – Current OR Ideal body weight whichever is lower

Ideal Body Weight Weight for height using a growth chart Weight for age Formulae in emergency

Growth Charts

Formulae <1 year : Age (in Months)+ 9/2 1-7 years : (Age x 2)+ 8 APLS : (Age in years + 4) x 2

Fluid Quota M + 5% = Maintenance + 5% of body weight Over 48 hours if patient presents in the beginning of critical phase (without shock) Over 24 hours for patients coming in shock

M + 5% - Adults Maintenance – 1st 10 kg – 1000 mls – 2nd 10 kg – 500 mls – Remaining 30kgs – 600 mls – Sum = 2100 mls 5% deficit – 50 x 50 = 2500 mls Total = 4600 mls

Child 22 kg Maintenance – 1000 + 500 + 40 = 1540 mls 5% Deficit – 50 x 22 = 1100 mls Total 2640 mls

Types of Fluid Crystalloids – 0.9% Saline – 5%Dextrose 0.9% Saline – 5% Dextrose ½ saline

Monitoring – Critical Phase Vital parameters - hourly Fluid balance chart - assess three hourly HCT - six hourly

Fluid Management in Dengue Shock Syndrome

Compensated Body compensates for fluid loss Tachycardia Pulse Pressure narrows Prolonged CRT Fall in urine output to 0.5 mls/kg/hr

Decompensated Pulse pressure narrows further leading to unrecordable pulse and BP Urine output falls less than 0.5 mls/kg/hour

Fluid Resuscitation Crystalloids – N Saline Colloids – Dextran 40 in N. Saline – 6% Starch All boluses part of fluid quota

Indications for Colloid Failure of crystalloid boluses to normalize pulse /BP Development of shock – with fluid overload – amount of fluid exceeding M + 5% deficit 10 ml/kg over 1 hour

Colloids Dextran may sometimes interfere with grouping and cross matching 3 doses of Dextran 40 during a 24 hour 5 doses of 6% Starch during 24 hour Remain in circulation for much longer

Refractory Shock - ABCS Blood – packed cells – whole blood Bicarbonate Glucose Calcium

Monitoring During Shock 15 minute monitoring of vital signs HCT immediately before and after each fluid bolus and then at least two to four hourly

Key Points – Managing DHF Recognizing the start of critical phase of DHF Predicting the rate of leak which may vary from patient to patient and within the same patient Matching the rate of infusion to rate of leak Being cognizant of the end of critical phase

Key Points – Managing DSS Meticulous monitoring Switching appropriately from crystalloids to colloids Recognizing need for blood transfusion