fluid responsiveness
DESCRIPTION
Fluid Responsiveness. Dr. Daniel Rankmore JHH ICU Junior Doctor Teaching 7 th March 2012. Today’s Topic. Why give fluids “Fluid responsive” What fluids are avalible. Why g ive fluids. the air goes in and out and the blood goes round and round. Oxygen Delivery (DO 2 ). - PowerPoint PPT PresentationTRANSCRIPT
Fluid ResponsivenessDr. Daniel Rankmore
JHH ICU Junior Doctor Teaching 7th March 2012
Today’s TopicWhy give fluids“Fluid responsive”What fluids are avalible
Why give fluidsOxygen Delivery (DO2)the air goes in and out and the blood goes round and round
Why give fluids
Intra-venous fluid
Intra-vascular volume
Cardiac Output
Tissue Perfusion
Oxygen Delivery
DO2 VO2> = Shock= Bad
DO2
Oxygenation
Cardiac Output+
DO2
Oxygenation
Cardiac Output+
(Bersten & Soni, 2009, pp. 317-318):
FiO2
Airway
Gas Movem
entHeam
Hb
TissueDiffusio
nCytochro
meMitochon
rial
Alveolar
Diffusion
DO2Cardiac Output
SV HR x
DO2Cardiac Output
SV HR x
PreloadContractilityAfterloadFilling Time
Frank StarlingSt
roke
Vol
ume
‘Preload’
A ‘normal’ heart
A heart ‘failing’
Frank StarlingSt
roke
Vol
ume
‘Preload’
500mlBolus
SVCO
Frank Starling CurveSt
roke
Vol
ume
‘Preload’
500mlBolus
SVCO
Frank Starling CurveSt
roke
Vol
ume
‘Preload’
500mlBolus
SVCO
EVLWPulmonary Oedema
Liberal Fluid Therapy compared with either Goal Directed Therapy or Restrictive Fluid Therapy3861 patients in 35 RCTsLiberal vs Restrictive
Pneumonia RR 2.2 95% CI 1-4.5Pulmonary Oedema RR 2.8 95% CI 1.1-13Longer Hospital Stay Mean 2 Days 95% CI 0.5-3.4
Goal Directed vs Not Goal DirectedPneumonia RR 0.7 (CI 0.6-0.9)Renal Complications RR 0.7 (CI 0.5-0.9)Reduced Hospital Stay Mean 2 Days (CI 1-3)
LiberalProlonged Hospital Stay Mean 4 Days (CI 3.4-4.4)Time to first bowel movement 2 Days (CI 1.3-2.3)
RCT 1000 patients with ALI 60 day follow upPrimary end point – mortality.Secondary end points – lung physiology, vent free days, organ failure free days7 day fluid balance 136ml vs. 6992mls.
Conserve
Liberal
p
Mortality
25.5%
28.4%
0.3
Vent Free Days
14.6 12.1 <0.001
ICU free days
13.4 11.2 <0.001
Shock & RRT
10% 14% 0.6
Three studies of colorectal surgeryReduced incidence of cardiorespiratory and fewer post operative problems.
88 patients undergoing major abdo surgery.PVI group – 500ml crystalloid bolus then 2ml/kg/hr if PVI <13% then 250ml colloid given, MAP maintained with vassopressors.Control group – 500ml crystalloid then fluid management per CVP and MAP.PVI group – improved intra-op and post op lactate and reduced total fluid input.
Retrospective review of IV fluids in the first 4 days of 778 patients in the VASST (Vasopressin in Septic Shock Trial)Conclusion:
A more positive fluid balance at 12 hours and 4 days was associated with increased mortality.CVP correlated with IV Fluid given for the first 12 hours.
When to give fluids
Fluid ResponsivenessGiving what the patient needs when the patient needs it
Fluid Responsiveness>15% increase in Cardiac Output following 500-1000ml fluid bolus
Static MeasurementsBP (MAP)UOCVPPAOP – ‘the wedge’ ITBVMVSaO2
IVC DiameterLVEDA
Central Venous PressureThe number that keeps getting measured…
Studies includedCVP & Blood volume (5 studies)CVP or ΔCVP cf: SI and CI pre & post boluses
(24 studies heterogeneous patient cohort including vascular surg, CABG, Sepsis, Health, 803 patients)
Central Venous Pressure
Central Venous PressureCVP & blood volume: 0.16 (95% CI: 0.03-0.28) CVP & SVI/CI: 0.18 (95% CI: 0.08-0.28) ROC 0.56∆CVP & SVI/CI: 0.11 (95% CI: 0.015-0.25)
ROC 0.5 true-positive = false positiveROC 0.9+ an adequate testConclusion
In none of the included studies was CVP able to predict fluid responsive or blood volume.
Central Venous Pressure
Hea32 healthy people given 3L saline over 3 hoursCVP PAOP useless..
Mixed Venous Saturations
Dynamic MeasurementsThe Fluid ChallengePassive Leg RaiseWaveform Analysis
Systolic Pressure VariationPulse Pressure VariationStroke Volume Variation
EchocardiographyPleth Variability IndexBioimpedance & Bioreactance
Fluid ResponsiveGive some fluid… see what happens…
Passive Leg RaisePLR. Free. Reversible. Effective.
39 patient. 4min PLR. 300ml bolus. Circ insufficiency and Mech Ventilation.Measurements: PP (rad artline), HR, PAOP, CO.Correlation between PLR and SV – 0.77 P < 000.1Correlation between PLR and Bolus – 0.84 P <000.1
Question: Can PLR induced ΔCardiac Output ΔPulse Pressure predict fluid responsiveness9 articles 353 patientsPLR-cCO – sensitivity 89.4% specificity 91.4%Not altered by ventilation mode or cardiac rhythm. PLR-cCO – ROC 0.95 cf. PLR-cPP – ROC 0.76 P<0.001
Thermodilution
How much water is in my bucket?
Thermodilution• Like the bucket analogy• Add to this concentration change over time
and • You can calculate flow
Waveform AnalysisNumerous. Complex. Useful.
Stroke Volume VarianceInvasive: pulse contour analysis (PICCO, LIDCO, Flotrac, Vigileo)Noninvasive: echo, pulse ox waveform,
Pulse Pressure Variance
Broad inclusion criteria: SVV, PVV, CVP, GEDI, ΔSV, & ΔCI compared with PEEP challenge or fluid challenge.29 studies 685 patientsBaseline and ΔCI
PPV (threshold 12.5%) – ROC 0.94 Sens 0.89 Spec 0.88 OR 59SVV (threshold 11.6%) – ROC 0.84 Sens 0.82 Spec 0.88 OR 27SBPV – ROC 0.86 CVP – ROC 0.55GEDI – ROC 0.56LVEDI – ROC 0.64
LimitationMandatory ventilation
PiccoThermodilutionWaveform analysis
Vigileo
EchocardiographyPretty. Skilled. Detailed. .
EchoSV = VTI x CSAVTI – AUC of dopplerCSA – valve area
Changes in resp cycle20% VTI12% peak flow
Bioreactance
110 Patients. PAC-CCO (thermodilution) cf. NICOMStable CO – correlation coefficient R = 0.82Increasing CO – correlation increased to 96%Decreasing CO – correlation decreased to 84-90%Changes seen on NICOM 3 +/- 3 minutes faster
75 Adult patients post cardiac surgeryCorrelation between PLR FR and NICOM and FRBut I couldn’t get the article in time…
Which fluids to give
Choice of IV therapyThink contentsThink compartmentsThink volume
Compartments
(Ganong’s Review of Medical Physiology, 23e)
The SalinesFluid Na Cl K Glucos
eOsmola
itypH
Plasma0.18% NaCl4% Glucose
30 30 - 40g/L637kJ
282 3.5-6.5
0.45% NaCl 76 76 - - 150 4.0-7.00.9% NaCl
“Normal Saline”154 154 - - 300 4.0-7.0
3%“Hypertonic”
513 513 - - 1000 4.5-7.0
23.4% 4000 4000 - - 80000.9% Saline + 30mmol KCL
154 184 30 - 368 3.5-7.0
0.9% NaCl + 40mmol KCL
100 140 40 - 280 4.0-7.0
The SugarsFluid Na Cl Glucose Osmolali
typH
PlasmaWater - - - -
0.18% NaCl + 4% Glucose
30 30 40g/L637kJ
282 3.5-6.5
0.45% NaCl + 2.5% Glucose
77 77 25g/L398kJ
292 3.5-6.5
5% Glucose - - 55g/L835kJ
278 3.5-5.5
10% Glucose - - 100g/L796kJ
556 3.5-6.5
50% Glucose - - 500g/L~4000kJ
Pre-mixed drinks and other concoctions
Fluid Na Cl Lactate
Ca K Bicarb
Mg Glucose
Osmality
pH
PlasmaCompou
nd Sodium Lactate“Hartma
n’s”
129 109
29 2 5 - - - 274 5.0-7.0
Plasma-lyte
140 98 - - 5 27Acetate
1.5 23 gluconat
e66kJ
294 4.0-6.0
Sodium Bicarb 8.4%
1000
- - - - 1000 - - 2000 7.2-8.7
Voluven 6%
154 154
- - - - - - 304 4.0-5.5
Blood ProductsFluid Na Cl Octonat
eAlbumin pH Osmol
Plasma4% Albumex 140 128 Octonate
6.440g/L 250
20% Albumex 48-100 Octonate 32
200g/L
pRBC
The Colloids
Double Blinded, RCT, 0.9% saline vs. 4% Albumin.6997 pt critically ill patientsPrimary Outcome: 28 day mortality.Secondary Outcomes: length of stay (ICU & Hosp), days on vent, days on RRT, new onset organ dysfucntion.Result: No difference.
Severe Sepsis subset analysis of SAFE Trial1218 patients AlbuminHR and CVP day 1-3 (p 0.002, 0.03)No diff Sequential Organ Failure Assessment (p. 0.98)Improved mortality 0.87 (CI 0.74-1.02, p 0.06)Multiriant logistic regression anaylsis mortality 0.71 (Ci 0.52-097, p 0.03)
460 patients, GCS 3-8.Post hoc subgroup analysis with 2 year follow upEnd point mortalityTotal Alb 71 of 214 0.9% 42 of 206 (RR 1.63 p 0.003)GCS 3-8 Alb 61 of 146 0.9% of 32 of 144 (RR 1.88 p <0.001)
Final ThoughtsConclusion
Understand the question you are asking.Think of fluids as you would a drug – dose, kinetics, dynamics, side effectsThink of alternatives – pressors or inotropes.Remember there are many tools in the toolbox.ABCD and repeat.