macken on burn resuscitation

Burn Resuscitation

– “Another bag of Hartmann’s?”

LEWIS MACKEN

Intensive Care UnitRoyal North Shore Hospital

November 2015

Think about that bolus of fluid you’ve just given.

It has to go somewhere.

Burn resuscitation

1. Over-resuscitate2. Success 3. Monitor4. Rescue5. Summary

Burn injury is a systemic injury >20% TBSA

Don’t try to get things to normal during the first 24 hours.

Case• 15 y old girl• Explosion BBQ• Intubated at scene• 30% TBSA burns• Parkland estimation (@ 70kg, 4ml/kg) = 8.4 L in 24 hrs • 6L given pre-hospital and ED in first 6 hours

What’s happening to her skin right now ?

Jackson’s Burn Model

Zone of stasis

• compromised but viable cells• decreased perfusion

• platelet aggregation• injured rbc• fibrin deposition

• endothelial swelling vasoconstriction• convert to complete tissue loss if:

• hypoperfusion / infection / oedema /ongoing heat

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Why do we give resuscitation fluids ?

Why do we give fluids in burns ?

Primary Goal

Maintain adequate tissue perfusion to end-organs and prevent ischaemic injury at the lowest physiological cost.

Universal Consensus for Burn Shock Resuscitation ?

Ann NY Acad Sci 1968

• Initial higher fluid volumes higher final volumes at 24 hours

• Initial lower fluid volumes lower volumes, no complications

J Trauma 2009

Why are we giving more fluid ?

1. Over-estimation of burn size2. Reluctance to decrease fluids3. ‘Opioid creep’4. ‘Normalise’ by maximising preload

Major burns & physiological derangement …

• Restoration of preload & cardiac function• Resolution of acidosis

24 – 36 hours

Determinants of success in burn resuscitation ?

Advanced haemodynamic monitoring to guide resuscitation ?

• ITBVI (ITTV & PTVGEDVITBVI) = R & L heart & pulmonary blood volumes at end-diastole

• CI only increased in GDT group at 24 hours, all identical at 48 hours• 60% failed to reach target• 56% more fluid (17 vs. 27L)• No difference in mortality, ICU days, ventilator days, pH, lactate, vasopressors

• “pure crystalloid solution is incapable of restoring cardiac preload during period of burn shock”

• ITBVI & CI• PiCCO 10L vs 7L standard• significant tissue oedema, even though the study group had 2x more u/o.

• the attempts to achieve normal haemodynamics were associated with significant tissue oedema, causing resuscitation attempts for some patients to stop

• “probably impossible to generate normal CO and normovolaemia during early post-burn period”

J Burn Care Res 2013

• Targets: CI .2.5L & normal ITBVI & lactate• Initially: low ITBVI/CI 2.68/lactate elevated• ITBVI remained low at 32 hours - but with normalisation of CI and lactate

= can achieve adequate resuscitation without normal preload• 4.75ml/kg/TBSA% & 23% mortality & 31% ARF (11.4% RRT) & 24.2%

ARDS & 12% ACS & 22 days mean on ventilator for mean TBSA 35%

Burns patients are different

• Restoration of preload & CO & resolution of acidosis takes 24-48 hrs

• Permissive hypotension• Permissive hyperlactataemia

CLOSE CLINICAL SUPERVISION

Rescue # 1

Colloid

Colloid Administration Normalizes Resuscitation Ratio and Ameliorates “Fluid Creep”

J Burn Care & Res 2010

Rescue # 2

1. Modified Parkland formula

2. Urine output + examine patient + other haemodynamic parameters

3. Slow early

4. Turn down

5. Rescue

6. Cardiac index sometimes

7. Don’t normalise

Summary