Multiorgan failure, nutrition and PCRRT

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Multiorgan failure, nutrition and PCRRT
4th International Conference on PCRRT

• Bernhard Frey
• Dep. of Intensive Care and Neonatology
• University Childrens Hospital Zürich

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Structure of the talk

• A PCRRT in MOF
• Do not focus on technology only
• B The benefits of PCRRT in MOF
• C Some practical aspects of CVVH

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Cascade effects of medical technology
A Do not focus on technology only
Deyo RA, Annu Rev Public Health, 2002

• Critically ill child
• Missing clinical skills
• Fluid overload
• Organ dysfunction (lungs, brain, heart)
• CVVH
• Side effects of CVVH

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Side effects of PCRRT (CVVH)
A Do not focus on technology only

• Complications with vascular access
• Thrombosis
• Infection
• Air embolism
• Bleeding (anticoagulation)
• Increased lactate (Barenbrock M, Kidney, 2000)
• Filtration of essential molecules
• Systemic inflammatory response syndrome (SIRS)

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CVVH Unintended consequencies?
A Do not focus on technology only

• No prospective studies demonstrating benefit of
  PCRRT (relating to relevant end-points)
• Renal replacement therapy independently
  associated with increased mortality
• (Metnitz P, Intensive Care Med, 2004)
• Experience with invasive technologies impacts on
  outcome (Tilford JM, Pediatrics, 2000)
• Invasive technologies may be dangerous in
  threshold countries

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CVVH Unintended consequencies ?
Invasive therapies in low risk patients
(Earle M, Crit Care Med, 1997)
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How to avoid PCRRT
A Do not focus on technology only

• Avoid fluid overload
• Prevention of ARF in MOF

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Fluid overload in MOF
A Do not focus on technology only
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Fluid overload in MOF
A Do not focus on technology only

• Stress, pain, nausea
• Vasopressin
• Morphine, barbiturates
• Capillary leak

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Fluid overload in MOF
A Do not focus on technology only

• Brain brain swelling
• Lungs higher fluid balance
• independent risk of mortality in ALI
• (Sakr Y, Chest, 2005)

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Fluid overload brain swelling
A Do not focus on technology only
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Fluid overload cerebral herniation
A Do not focus on technology only
ICP
Intracranial volume
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Maintenance fluid
A Do not focus on technology only

• Holliday MA and Segar WE, Pediatrics, 1957
• Fluid requirements calculated by caloric
  expenditure
• However Sick children need much less fluids
• lower caloric intake
• lower urinary excretion
• decreased insensible losses

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How to order maintenance fluids
A Do not focus on technology only
Analysis of

• Total body water
• weight, edema/dehydration, fluid balance
• Blood volume
• microcirculation, diuresis, heart rate, (CVP,
  BP)
• Electrolytes
• Na

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Fluid requirements in ventilated children
A Do not focus on technology only

• lt 10 kg 50 ml / kg / d
• gt 10 kg 1200 ml / m2 / d
• extra boluses (NaCl 0.9) to increase cardiac
  output
• Give enteral feeds instead of free water drips

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Volume to optimize preload
A Do not focus on technology only
(Michard F, Crit Care, 2000)
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Prevention of ARF in MOF
A Do not focus on technology only

• Optimize perfusion pressure and O2-delivery
• O2-delivery Cardiac Output x Hb x SaO2
• Avoid intraabdominal hypertension

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A Do not focus on technology only
Measurement of intraabdominal pressure
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PCRRT
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The benefits of PCRRT in MOF
B Benefits of PCRRT

• Indication
• Fluid overload
• ARF
• Inadequate nutrition

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The benefits of PCRRT in MOF
B Benefits of PCRRT

• Commencing PCRRT early may be beneficial
• (Goldstein S, Pediatrics, 2001)

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Enteral nutrition in PICU
B Benefits of PCRRT

• Early enteral nutrition
• decreased length of hospital stay
• less infections
• improved wound healing

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Enteral nutrition in PICU
B Benefits of PCRRT
(Rogers EJ, Nutrition, 2003)
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Enteral nutrition in PICU
B Benefits of PCRRT

• Energy supply is often inadequate
• Reasons Fluid restriction
• Interruption of nutrition
• Measures start enteral feeds early
• Give feeds, not water drips
• early jejunal nutrition
• favor enteral feeds
• PCRRT

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Practical aspects of PCRRT (CVVH)
C Practical aspects

• Vascular access
• Nutrition
• Drug dosing
• (Review Norma Maxvold, Timothy Bunchman,
• Crit Care Clin, 2003)

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Vascular access
C Practical aspects
Neonate, 2.5 kg MEDCOMP 7 F, 10 cm Filling
volume 0.8 0.8 ml
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Vascular access
C Practical aspects
Neonate, 2.5 kg MEDCOMP 7 F, 10 cm
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Nutrition in CVVH
C Practical aspects

• The filter is highly permeable to water and other
• small molecules
• amino acids
• trace elements Double intake
• water soluble vitamins

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Nutrition in CVVH
C Practical aspects

• The net ultrafiltration rate has to be set to
  allow
• adequate nutrition
• lt 1 year EBM / infant formula trace elements
  vit.
• gt 1 year Formula (Frebini) trace elements
  vit.
• (Whole protein formula)

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Drug dosing Factors affecting drug elimination
C Practical aspects

• Factor Importance
• Ultrafiltration rate low
• Molecular size low
• Drug-protein binding high (sieving coeff.)
• Volume of distribution high
• Physiological elemination high

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Drug dosingDrug specific numbers
C Practical aspects

• Sieving coefficient (Sc)
• Sc Cuf / Cp (0 1)
• Cuf drug concentration in ultrafiltrate
• Cp drug concentration in plasma
• Volume of distribution (Vd)

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Drug dosing practical approach
C Practical aspects

• Clinical signs of response or intoxication
• Drug concentration monitoring (whenever possible)