1.Intravenous Fluids in Children
NPSA Guidelines
Dr Pam Cupples
SPAN Meeting Friday the 20th of April 2007
Dunkeld
2.Aims
Historical approach to fluid management based on Holliday & Segar’s ‘4/2/1’ formula
Problems with hypotonic fluids in the Paediatric Population
NPSA guidelines
3.Maintenance Fluid Requirements
Maintenance fluid requirements parallel energy metabolism
Energy Expenditure - using tables and nomogram
Darrow et Pratt, JAMA 1950
Body surface Area – Crawford et al, Pediatrics 1950
Age - Wallace, Am. J. Clin. Path. 1953
Weight – Holliday & Segar, Pediatrics 1957
4.Holliday & Segar’s Formula
‘healthy’ infants and children
Energy expenditure at rest and during activity
Energy expenditure equated to water requirements
1ml of water required to burn 1 calorie
1.2mls water are consumed
0.2mls water are produced
3mmols/kg of Na
2mmol/kg of K
Infants require ~ 100cal/kg/day
Older Children ~ 75cal/kg/day
Adults ~ 35cal/kg/day
Calorie Requirements
100cal/kg/day <10kg
50cal/kg/day 10-20kg
20cal/kg/day >20kg
Hypotonic fluid
0.18% NaCl with 4% Dextrose
5.How we got the ‘4-2-1’ rule
Calorie Requirements Based on Weight
0-10kg: 100cal/kg/day
10-20kg: 1000cal + 50cal/kg/day for each kg over 10kg
> 20kg: 1500cal + 20cal/kg/day for each kg over 20kg
Water Requirements – ‘ 4-2-1 rule’
0-10kg: 100 water/kg/day
( 4ml / kg/ hour)
10-20kg: 1000 water + 50 water/kg/day for each kg over 10kg
( 2ml/kg/hour)
> 20kg: 1500 water + 20 water/kg/day for each kg over 20kg (1ml/kg/hour)
6.Holliday & Segar - the flawsThe Maintenance Need for Water in Parenteral Fluid Therapy– Pediatrics 1957
WEIGHT
Illner et al 2000 - resting energy expenditure is based on fat free mass
Accounts for 80% of the BMR but only 7% of the total body mass
Calculating energy expenditure based on weight significantly over estimates the calorie requirements and hence the water requirements
7.Energy Expenditure
No allowance for the different energy expenditure in acute disease / post surgery
Actual energy expenditure is 50% lower than values used by Holliday & Segar
Briassoulis et al, 2000
Lindahl et al, 1988
Lower energy requirements due to :
50% of calorie expenditure allowed for growth
Catabolic state
Inactivity
PICU setting – IPPV / sedated and paralysed
Exceptions – fever,sepsis & burns
8.Water Losses
Insensible water losses 27ml/kg/day
Heeley & Talbot , 1955
50% of this value – Lamke, 1977
Skin 7ml/kg/day
Lungs 5ml/kg/day
Urinary losses
50-60ml/kg/day Holliday & Segar, 1957
No allowance for non-osmotic stimuli for ADH
Stress, pain, surgery, fever
Drugs – opioids, NSAIDs
Urinary volume reduced to 25ml/kg/day
Endogenous water production from tissue catabolism
in acute illness
9.
10.Hazards of Hypotonic FluidsAcute Hospital Acquired Hyponatraemia
Prescription of hypotonic fluids
Provision of excess free water in conditions where patient unable to excrete the excess water load
Non – osmotic stimuli for ADH
12.Hazards of Hypotonic FluidsAcute Hospital Acquired Hyponatraemia
Acute Hyponatraemia
Na < 136mmols/L occurring within 48 hours
Severe hyponatraemia if Na < 130mmols/L
Or any level of hyponatraemia associated with clinical signs
Risk group
Children
Premenopausal women
Hypoxia
Hyponatraemic encephalopathy
50% of children with Na<125mmol/L
8% mortality rate
Risk of developing hyponatraemia with hypotonic fluids is 17.2 times than with isotonic fluids
Choong et al, 2006
Children have a poorer outcome than adults for a given level of hyponatraemia
13.Acute Hospital Acquired Hyponatraemia – children at risk
Common symptoms
Headache
Nausea & vomiting
Weakness
Advanced signs
Seizures
Respiratory arrest
Dilated pupils
Decorticate posturing
Coma
Pulmonary oedema
14.Risks of Hypotonic Fluids
50 cited cases of child death or neurological injury in the international literature
4 deaths and 1 ‘near miss’ in the UK since 2000
Post-op setting in previously healthy children
Minor surgical procedures
15.Conclusions
Hypotonic fluids are not benign but potentially dangerous
17.2 times more likely to develop hyponatraemia with hypotonic fluids than with isotonic
Isotonic fluids offer a safe alternative to hypotonic fluids with no risk of hypernatraemia
Fluid regimes should be tailored to the individual
Appropriate monitoring
Weight, baseline U&E’s
16.Background to the NPSA
March 2003 – RCA asked by the RCPCh to issue warning re. The use of 0.18% Saline in 4% Dextrose
November 2004 – Inquiry set to investigate the deaths of 3 children from hyponatraemia following a documentary
Audit in 2004/2005 – few anaesthetists had seen the warning
NPSA – advice to healthcare professionals on how to reduce risk develop solutions and introduce them into clinical practice
17.NPSA Plan of Action
July 2005 – form an internal working group to assess problem
August 2005 – External working group appointed after
October to November 2005 – meetings of the external group to discuss evidence collected
Dec 2005 – draft of the safe practice recommendations
Jan-Feb 2006 – Wide stakeholder consultation on draft
April 2006 – publish NPSA guidance
18.NPSA – Patient safety alert 22: Reducing the risk of hyponatraemia when administering intravenous infusions to children (Alert 5 of 5)Applies to all paediatric patients from 1 month to 16 years28th March 2007
Remove 0.18% NaCl / 4%Dextrose from general stock
Produce and disseminate clinical guidelines for the fluid management of paediatric patients
Adequate training and supervision of staff
Reinforce safe practice
Promote the recording and reporting of hospital acquired hyponatraemia
Audit programme to ensure that the NPSA recommendations are being adhered to
19.NPSA guidelines
Template for developing local guidelines for the prescription & monitoring infusions in children
Importance of rigorous clinical and laboratory monitoring
Prescription of fluids same importance and consideration as other medicines
Fluids must be individualised
Calculate fluid balance and monitor plasma Na
20.Oral fluids preferable to iv
Resuscitation Fluids – bolus of 0.9% saline
Deficit – calculated and replaced as 0.9% saline or 0.9% saline with 5% dextrose
Replace over 24 hours
Maintenance – do not use 0.18% saline with 4% dextrose
0.45%saline with 5% dextrose
Children at high risk – only isotonic fluids
Peri and post operative
Na levels lower end of normal or <135mmol/L
Volume depleted
Hypotension
CNS infection
Head injury
Bronchiolitis
Sepsis
Excessive gastric / GI losses
Chronic conditions – CF,IDDM
Salt wasting syndromes
21.NPSA Guidelines
Ongoing losses
Assessed 4 hourly
Replacement fluid should reflect the type of electrolyte composition of the fluid being lost
Isotonic safest choice
Monitoring
Robust regime
Weight of child
Baseline and daily measurements of Na, K, urea & Cr
More frequent if Na already low or clinical picture changes
Training
E-modules to assess current level of competencies & knowledge
Doctors in training (80-90%)
Review their fluid prescriptions
IV Prescription Charts
Review & redesign – include guidelines on fluid presciptions
Monitoring data required
How to calculate fluid requirements
22.
23.www.npsa.nhs.uk/health/alerts
24.Arieff et al, BMJ 1992
Prospective clinical case study
16 children who died or developed permanent neurological damage
0.34% incidence of post-op hyponatraemia
(83 affected out of 24,412 patients)
8.4% mortality rate
(7 deaths)
Halberthal et al, BMJ 2001
23 patients
13 hyponatraemic in post-op period
15 referred to critical care
11 from wards and 4 from other institutes
Seizures (18) and vomiting (17)
5 had Rx withdrawn due to brainstem herniation
1 patient sustained permanent, severe neurological damage
16 / 23 receiving maintenance fluids at 50% more than recommended values
25.Paut et al,
Ann Fr Anesth Reanim 2000
7 Children 3-6 years
ASA 1-2
Scheduled surgical procedures
Vomiting, seizures, status or GCS (5/7)
1 respiratory arrest with Na 120mmol/L
All had hypotonic fluids
3/7 IPPV
Rx – fluid restriction, NaCl
1 death
McRae et al, Int J Pediatr Otorhinolaryngol 1994
3 post-op tonsillectomy patients
2 deaths
26.Choong et al, 2006
Systematic review
6 studies satisified inclusion criteria
2 unmasked RCT
1 non randomised CT
3 observational studies
Mean Na in hypotonic group –3.39mmol/L
Small number of studies with small group size
Total of 404 patients
27.Holliday & Segar
0-10kg: 100cal/kg/day
10-20kg: 1000cal + 50cal/kg/day for each kg over 10kg
> 20kg: 1500cal + 20cal/kg/day for each kg over 20kg