1 Fluid and electrolyte therapy Dr Ed Simmonds Consultant Paediatrics UHCW

2 Case 1 Four year old weighing 15 Kgs, 24 hour history of D & V. Looks unwell/dehydrated. Trial of oral fluids initially not tolerated. Admitted for management with fluids. How will you proceed?

3 General principles n Maintenance fluid: replaces usual losses of fluid and electrolytes n Deficit : designed to replace abnormal losses due to disease n Supplemental fluid: replaces measured or estimated continuing abnormal losses (eg loose stools)

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5 Normal maintenance requirements

Calculate maintenance requirements 6 100mls/kg x 10 = 1000mls 50mls/kg x 5 = 250mls Total = 1250mls/24hrs Prescription 52mls/hr

Dehydration 7

Diarrhoea and vomiting in children under 5 Assessing dehydration slides Implementing NICE guidance 2009 NICE clinical guideline 84

Symptoms of increasing severity of dehydration No clinically detectable dehydration Clinical dehydrationClinical shock Appears well Appears to be unwell or deteriorating – Alert and responsive Altered responsivenessDecreased level of consciousness Normal urine outputDecreased urine output– Skin colour unchanged Pale or mottled skin Warm extremities Cold extremities

Signs of increasing severity of dehydration No clinically detectable dehydration Clinical dehydrationClinical shock Alert and responsive Altered responsivenessDecreased level of consciousness Skin colour unchanged Pale or mottled skin Warm extremities Cold extremities Eyes not sunken Sunken eyes - Moist mucous membranesDry mucous membranes - Normal heart rate Tachycardia Normal breathing pattern Tachypnoea Normal peripheral pulses Weak peripheral pulses Normal capillary refill time Prolonged capillary refill time Normal skin turgor Reduced skin turgor - Normal blood pressure Hypotension

Dehydration symptoms/signs n Clinical dehydration = 5% n Shock = 10% 11

Calculate deficit 5% dehydration 15kg = 15,000mls 1% = 150mls 5% = 750mls 12

Case 1 - fluid volume prescription n Maintenance plus deficit prescribed over 24 hours n = 2000mls n 83mls/hr 13

Normal maintenance requirements

Oral or nasogastric fluids n Rehydrate with low osmolarity rehydration solution (ORS) n Hypo-osmolar to prevent osmotic diarrhoea n 60mmol Na per litre 20mmol K 60mmol Cl 90mmol Glucose 15

Intravenous fluids 0.9% sodium chloride 150mmol/litre Na 0.45% sodium chloride/5% glucose 75 mmol /litre Na + 5 grams glucose 0.9% sodium chloride/5% glucose 150mmol/litre Na + 5 grams glucose

17 Case 2 Two year old weighing 12 Kgs. 48 hour history of D & V. Drowsy, cold hands and feet. HR 180, RR 40, CRT 4 seconds How will you proceed?

Management of shock n ABC n Oxygen n Venous access – bloods for glucose and renal biochemistry (minimum) n 20mls/kg of 0.9% saline n Subsequent rehydration 18

Calculations n Maintenance 10 x 100 = x 50 = 100 Total = 1100 n Deficit 10% of 12,000 = 1200 n Total 2300mls/24hrs = 96mls/hr 0.9% sodium chloride/5% glucose

Electrolyte results n Hyponatraemia <130mmol/litre n Normal 135 – 145mmol/litre n Hypernatraemia >145mmol n Hypokalaemia <3.5mmol/litre n Normal 3.5 – 5.0mmol/litre n Hyperkalaemia >5.0mmol/litre

Hypernatraemic dehydration n Cautious fluid replacement n Suggested replace deficit over 48hrs n Reduce plasma Na by no greater than 0.5mmol/hr Concern re cerebral oedema

Diabetic ketoacidosis n Cautious fluid replacement n If shocked initial bolus 10ml/kg (repeat if felt necessary). n Subtract fluid bolus from deficit calculations n Suggested replace deficit over 48hrs n Reduce plasma Na by no greater than 0.5mmol/hr

Potassium n Usually 20mmol/litre for maintenance fluids n When treating dehydration add 20mmol/litre potassium chloride to fluids when happy that passing urine