Obligatory joke Keep your eye on the food. Goal-Directed Fluid - - PDF document

6/1/2013 1 Goal-Directed Fluid Resuscitation

Christopher G. Choukalas, MD, MS

Department of Anesthesia and Perioperative Care University of California, San Francisco

Obligatory joke

• Keep your eye on the food.

The case for why it matters

• Fluid balance a common concern
• Sepsis
• ALI/ARDS
• Sepsis PLUS ARDS!

Sepsis: More is more

• Some impressive fluid totals

Study Control Intervention Jansen (8 hrs) 2.2L 2.7L Jones (6 hrs) 4.5L 4.3L Rivers (6 hrs) 3.5L 5L

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Or is it?

• Retrospective analysis of VASST trial

– 778 pts w/ septic shock on NE

• Divided into quartiles based on total fluid

in at 12 hrs, 4 days

Dry Quartile Wet Quartile 12 hours +0.7L +8.2L 4 days +1.6L +20.5L

Boyd, JH, et al. 2011. CCM. 39(2)

Sepsis +  CVP = Death

• Outcomes: Quartile x 28 d mortality
• Early (12 hrs) and Late (4 d) “dry-ness”

saved lives:

– HR 0.57 and 0.47, respectively

Survival Dry Quartile Wet Quartile 12 hours 81% 58% 4 days 83% 65%

Boyd, JH, et al. 2011. CCM. 39(2)

Just the FACTTs

• 1001 w/ ALI randomized to liberal or

conservative fluid algorithms

• Varying amounts of fluid, furosemide,

dobutamine

Outcome Conservative Liberal Fluid total (day 7; mL)

• 136

+6990 Vent-Free days ICU-Free days Dialysis CNS failure free days

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Outcome Conservative Liberal Mortality (60d) 25.5% 28.4% (ns) Vent-Free days ICU-Free days Dialysis CNS failure free days Outcome Conservative Liberal Mortality (60d) 25.5% 28.4% (ns) Vent-Free days +++ ICU-Free days +++ Dialysis CNS failure free days Outcome Conservative Liberal Mortality (60d) 25.5% 28.4% (ns) Vent-Free days +++ ICU-Free days +++ Dialysis Less More (ns) CNS failure free days +++

• Patients with Sepsis who developed ALI
• 4 groups:

– Adequate initial + Conservative late fluids – Adequate initial only – Conservative late only – Neither

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Murphry, CV, et al. 2009. Chest. 136(1)

It matters

• So how do we do it?

I would posit two factors:

• Hemodynamic:

– Is the circulation adequate?

• Metabolic

– Are oxygen delivery and utilization adequate?

• Both have their own goals.

Hemodynamic Goals

• Blood pressure
• CVP
• Dynamic respiratory indices:

– Pulse pressure/systolic pressure/perfusion index variation

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Hemodynamic Goals

• Blood pressure
• CVP
• Dynamic respiratory indices:

– Pulse pressure/systolic pressure/perfusion index variation

Blood pressure

• A proxy for flow, end organ perfusion
• Flow = pressure/resistance
• Do we ever really KNOW resistance?

Wax, et al.

• Non-cardiac cases with both ABP and

NIBP.

• Compared SBP, DBP, and MAP btwn

technologies:

– A-line alone vs A-line + cuff

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Randomized trials Interesting review

• Reviewed 2 trials and 1 meta-analysis (13

studies)

– Target BP – Actual BP

• Dissociation

– BPs invariably higher than goal – Higher goal ranges permitted higher actual ranges:  pressors

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Blood pressure

• Necessary but not sufficient
• Goals are nebulous
• Supra-normal levels common, not helpful

Hemodynamic

• Blood pressure
• CVP
• Dynamic respiratory indices:

– Pulse pressure/systolic pressure/perfusion index variation

Concept: assumptions

Adequate DO2 Adequate contractility Optimal actin-myosin match Normal CVP

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The data

• Critical target in EGDT for sepsis
• Incorporated into SSC guidelines

Marik, PE, et al. 2008. Chest. 134(1)

Fluid responsiveness and total blood volume

• Prong one:

– Volume responsiveness – Cardiac output before and after fluid challenge – 19 evaluated CVP and volume responsiveness

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Fluid responsiveness

• Calculated a Receiver Operating

Characteristic curve

• Likelihood that at any given point (CVP

level, score, etc) the true positives will exceed false positives.

• Higher = better discrimination

Volume responsiveness

Marik, PE, et al. 2008. Chest. 134(1)

CVP

• Necessary?
• Certainly not sufficient
• Potentially misleading

Hemodynamic

• Blood pressure
• CVP/wedge
• Dynamic respiratory indices:

– Pulse pressure/systolic pressure/perfusion index variation

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The Principles

Decreased RV SV

 RV Preload  RV Afterload

 LV Preload  LV SV

Applies to lots of measures

• Systolic pressure variation
• Pulse pressure variation
• Plethysmogram variation
• Outcome is “fluid responsiveness”

Variations on a theme…

• A waveform…
• A peak and trough…
• And a proprietary algorithm:

The data

• Small studies
• Mostly OR

SVV, Vigileo 40% MORE fluid Lower lactate Fewer “complications” PVI, Masimo 1/3 LESS fluid Lower lactate

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• 29 studies, 685 patients

– 9 ICU – 20 OR (15 in cardiac surgery)

• All included correlation/ROC between

SPV, PPV, or SVV and ΔSVI/CI after a fluid challenge.

Measure r AUC for ROC Threshold PPV 0.78 0.94 12.5% SVV 0.72 0.84 15.3% SPV 0.72 0.86 CVP 0.56

ECOM ECOM

• ETT-based electrodes
• Current generated by flow in ascending

aorta

• Current + Nomogram = SV
• SV  CO, SVV
• R2 = 0.63

Wallace, AW, et al. Under Review.

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Now, keep in mind…

• Regular HR
• Sedated, mechanically ventilated
• Vt = 8 mL/kg
• Pressors?

PVI + NE = NEB

Monnet, et al Biais, et al Population 35 ICU patients on NE 35 ICU patients on NE Gold Standard TD PPV > 13% SensitivityFR 43 58 SpecificityFR 90 61 AUCROC 0.68 0.69 100 72 0.93 Monnet, et al Population 35 ICU patients on NE Gold Standard TD SensitivityFR 43 SpecificityFR 90 AUCROC 0.68

Hemodynamic goals

• Numerous
• State of the art: Dynamic indices

– PPV – SPV – PVI – VTI and esophageal doppler

• Necessary but not sufficient

Metabolic

• Mental status, urine output
• Lactate
• S(c)vO2

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Metabolic

• Mental status, urine output
• Lactate
• S(c)vO2

Physical exam

• Evidence of end-organ perfusion and

function

• Slow to change
• Numerous confounders
• Summarily dismissed

Metabolic

• Mental status, urine output
• Lactate
• S(c)vO2

Lactate

• The product of anaerobic respiration
• Presence implies inadequate oxygen

utilization, shock

• Easily, quickly measured in arterial blood

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Lactate: the data Two trials:

• JAMA: 300 patients, EGDT vs lactate

clearance

– Non-inferiority

• AJRCCM: 348 patients, EGDT vs lactate

clearance

– Improved mortality (multivariate) – Less time on vent, in ICU

How did they do it?

Jones, et al (JAMA) Jansen et al (AJRCCM) Monitoring interval 2 2 Goal 10% clearance 20% clearance Fluid totals (L) Control: 4.3 Intervention: 4.5ns Control: 2.2 Intervention: 2.7* Outcome Non-inferiority to EGDT Decreased time on vent, in ICU

The underpinnings…

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Metabolic

• Mental status, urine output
• Lactate
• S(c)vO2

How it’s used:

 ScvO2 attributed to:

 Supply (cardiac output)  Demand (hypermetabolism)

• In either case, treat by increasing DO2

– Volume, inotropes, RBCs

• But does it work?

ScvO2

• The cornerstone of Early Goal-Directed

Therapy.

• And we know that targeting SvO2 

mortality.

– Septic, cardiogenic shock in humans, dogs – ScvO2 = SvO2?

ScvO2 SvO2

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DOGS

Humans w/ sepsis Humans w/ shock Changes in SvO2 and ScvO2

Metabolic goals

• Lactate and ScvO2

– Base deficit? – A-V (CO2) gradient? – A-V (CO2)cer gradient?

• Physiological rationale meets objective

data.

Putting it all together:

• Volume isn’t easy
• Volume is important
• Common conditions; competing goals
• Stepwise plan

– Hemodynamic – Metabolic

The end

The End