goal directed fluid therapy: fact, fiction, findings and the future

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Goal Directed Fluid Therapy:Fact, Fiction, Findings and the Future

Chuck Vacchiano, PhD, CRNA, FAAN

Duke University Nurse Anesthesia Program

Copyright 2016. Charles Vacchiano. All rights reserved

Objectives

• Review the basic assumptions of perioperative fluid therapy.

• Review conventional perioperative fluid administration and examine its doctrine.

• Discuss provider variability with respect to fluid administration

• Examine factors related to intravascular volume, stroke volume, tissue perfusion and oxygen delivery.

• Define Goal Directed Fluid Therapy, discuss its physiologic foundations, and review its target endpoints.

• Review the evidence based literature outcomes.

• General Recommendations.

The Basic Assumptions:

• Too little fluid is bad

• Too much fluid is bad

• Just the right amount of fluid is good ?

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To Little Fluid: Hypovolemia

• Hypovolemia contributes to inadequate tissue perfusion and postoperative complications

• Heart rate, blood pressure, urine output and central venous pressure are Not Reliable Measures of Volume Status

• Standard hemodynamic monitors fail to detect “occult” hypovolemia which contributes to inadequate tissue perfusion

• By the time hypotension is apparent tissue hypoperfusionhas already occurred

Navarro et al., Perioperative Medicine 2015Gupta and Gan., World Congress of ERAS and Periop Med 2015

To Much Fluid: Hypervolemia

• Average 3 to 10 kg weight gain following major surgical procedures

Weight gain < 10% associated with 10.3% mortality rate

Weight gain > 10% associated with 31.6% mortality rate

• Postop pulmonary edema when volume exceeded 67 mL/kg/hr

• Healthy volunteers: Fasted / 40 mL/kg/hr LR over 3 hours

Significant decrease in FEV1 and FVC lasting 8 hours

Median weight gain = 0.85 kg 24 hours after bolus

• Manipulation of the bowel results in increase of 5 to 10% intestinal weight at anastomosis

• Tissue edema is associated with decreased oxygen tissue tension and impaired wound healing

Joshi, Anesth Analg 2005 Lowell et al., Crit Care Med 1990 Arieff, Chest 1999Holte et al., Anesth Analg 2003 Chan et al., Br J Surg 1983

Hypovolemia HypervolemiaEuvolemia

Fluid Optimization

Volume Status

Perioperative Complications

Suehiro et al., Curr Anesthesiol Rep 2014

Just the Right Amount of Fluid: Euvolemia

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Optimization of Intravascular Fluid Volume Through Goal Directed Fluid Therapy (GDFT)

• What is GDFT?– The use of some measurement of cardiac output to

guide intravenous fluid therapy in an attempt to ensure adequate tissue perfusion…..

….and presumably oxygen delivery

and cellular oxygenation

– Rational• Restoring or improving oxygen delivery repays or

prevents an oxygen debt

• Needs to occur early to prevent organ damage

Conventional Intraoperative Fluid Administration

• Conventional intraoperative fluid administration is guided by:

– Deficit / Maintenance (Insensible/Sensible Loss) Replacement

• 4:2:1Rule: Fixed values based on BW

– Estimated Blood Loss Replacement

• Highly subjective and generally unreliable

– Third Space Loss Replacement

• Non-functional space

• Based on estimate of degree of tissue trauma

Where Did the Conventional Fluid Administration Strategy Come From?

• The “Holy Grail” of Fluid Management:

– Fasting patients are hypovolemic

– Insensible losses increase dramatically with skin incision

– Fluid shift into the “Third space” must be accounted for

– The kidneys will handle excess fluid

– Fluid unlike vasopressors are always safe

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The Evidence Regarding Fasting Hypovolemia and Insensible - Incisional Loss

• The belief that all surgical patients are hypovolemic is unfounded

• There is no significant intravascular deficit after fasting

• Basal fluid insensible loss is approximately 0.5 ml/kg/hr

• Evaporation from the surgical wound:

– Small incisions without exposure of the viscera 2 ml/hr

– Moderate incisions with partial exposure of the viscera 8 ml/hr

– Large incisions with completely exteriorised viscera 32 ml/hr

• Abdominal insufflation with dry gas for extended periods does not result in significant fluid loss (< 1ml/hour)

Muller et al. BJA 2014 Hahn et al. Acta Anaesthesiol Scand 2014 Lamke et al. Acta Chir Scand 1977Navarro et al. Perioperative Medicine 2015 Biegner / Vacchiano et al. JLAST 1999

Let’s think about the worst case scenario:5 Hr Open Bowel Resection, 100 kg Patient:

Insensible Loss = 250 mLSurgical Wound = 160 mLTotal Fluid Loss = 410 mL

C1 x V1

C1 x V1

Let’s Talk About the Evidence for Third Space LossBackground: Measuring Body Fluid Volumes

C1 x V1 = C2 x V2

V2 = C1 x V1

C2

C2 x V2

C2 x V2V2 = C1 x V1

C2

C1 x V1

C1 x V1

?

?


• Tracer dilution technique for determining an unknown volume: 1. Select a tracer compound (C1 and V1)

2. Inject tracer into the vascular space

• Allow time to completely distribute and equilibrates across compartment(s) of interest

3. Measure the tracer concentration in the blood (C2)

4. Calculate the Volume of Distribution, VD (V2 ):

• Volume of Distribution(VD) = Amount Tracer in Body

Plasma Tracer Concentration

• C1 x V1 = C2 x V2 V2 = C1 x V1 = 1mL x 100mg/mL = 14 Liters

C2 .0071 mg/ml

Elsevier, Guyton & Hall, Textbookof Medical Physiology, 11edition

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• Key Elements: Tracer Equilibrium and Final Concen.

– Achieving Tracer Equilibrium is Essential!

• Equilibrium time is different for different tracers

– Ways to Measure Tracer Final Concen.

• Single Sampling (A):

– Assumes equilibration

• Multiple Sampling (A,B,C,D,E) :

– Repeated sampling until equilibration is achieved

(C1 x V1)

Serum Concen.(C2)

A

BC D E

The Birth of the “Third Space”

• Shires et al. (1961) postulated a decrease in the functional ECFV (Plasma + ISF) compartment during surgical trauma

– ECFV was measured before incision and at 2 hours

• Control group: 5 minor surgical procedures

• Experimental group: 13 major surgical procedures

– All received general anesthesia

– Surgical tissue trauma was subjectively ranked

– Tracer 35SO4 20 minute equilibration single samples

– Calculated ECF Volume


• Shires reported a reduction in the ECFV that exceeded blood loss in the experimental group

• Concluded

– The contraction of the ECFV beyond the blood loss was due to:

• Sequestration of fluid into a compartment no longer able to participate in the equilibration process

• “Non-Functional Space”

– The contraction correlated to degree of surgical tissue trauma

– This fluid shift is distinct from movement into the ISF space

• Which is returned to the circulation via lymphatics

• Functional Volume

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• Criticisms of Shires work:

– Short measurement period (20 min) / Single Sample

• Inadequate tracer equilibration time produced falsely high blood concentration (C2) and falsely low ECF Volume (V2)

– Inability to replicate the findings with other tracers

– Subsequent studies with various tracers and/or longer equilibration times contradict the existence of a third space

The Evidence for Criticism: The Power of Replication

• 4 Human Hemorrhagic Shock Studies

– Minimal evidence of a Third Space in the presence of moderate or severe hemorrhagic shock

• Third space found in 1 study using 35SO4 tracer / 20 minute equilibration time

• 16 Human Abdominal Surgery Studies– Third Space only found when using the 35SO4 tracer and a short

equilibration time

– Studies using longer equilibration times regardless of single or multiple sampling do not suggest the existence of a Third Space

• 12 Human Thoracic Surgery Studies

– None used 35SO4 and the 20 minute equilibration time

– None suggested the existence of a 3rd space

• The ECFV appeared to be unchanged or expanded postop

Extracted from Brandstrup B. Holbaek University Hospital, Denmark. Presentation 2003

Analysis of the Replication Evidence

• The evidence for a Third Space loss is derived from a total of 4 human studies:

– Published in 1961, 1962, 1966 and 1967

– Method in these studies: Injection of 35SO4 tracer and a 20 to 30 minute equilibration time

• No convincing evidence supporting the existence of a non-anatomical 3rd space

• Excessive fluid, mechanical tissue injury, and inflammation simply lead to an increase in Interstitial fluid

• Questions the wisdom of administering 2 to 8 ml/kg/hr or more to replace third space losses

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Fluid More FluidProvider Variability in Fluid Administration

• 2 Academic Medical Centers in the U.S / No fluid admin. guidelines • Accounted for individual variation in the cases • Variability of fluid administration within and between providers

expressed as:• Corrected Coefficient of Variation (cCOV): Provider standard deviation

Mean of the entire sample

• Mean fluid administration across all providers = 7.1 ml/kg/hr• ASA I Mean 9.9 6.2 ml/kg/hr / cCOV of 87% • ASA III Mean 6.9 4.7 ml/kg/hr / cCOV of 66%

• Lowest individual provider variation = 26% • Highest Individual provider variation = 141%

• Example: A 75 kg patient undergoing a 4 hr operation with minimal blood loss could receive between 700 and 5400 ml of crystalloid during surgery depending on the provider

Lilot et al., Br J Anaesth 2015Minto & Mythen, Br J Anaesth 2015

Fluid More FluidProvider Variability in Fluid Administration

• Is the variability unique to the 2 institutions in the study? No

• If we are truly good at managing perioperative fluid therapy shouldn’t we expect to see some consistency across any particular surgical procedure?

– There was not.

• Did other endpoints like MAP, HR, EBL, Surg. approach and type have any impact?

– Had little to no impact

• Most important predictor of fluid volume administered was the individual provider

• Take Home:

– Fluid administration was largely based on provider habit or…..

– There is great inconsistency in the way providers interpret and respond to hemodynamic and clinical signs

Lilot et al., Br J Anaesth 2015Minto & Mythen, Br J Anaesth 2015Gustafsson et al., Arch Surg 2011

Some Demographics

• Estimated 240 million anesthetics worldwide per year– 24 million (10%) administered to “high risk” patients– Accounts for more than 80% of overall surgical mortality

• 96 million (40%) administered to “moderate risk” patients– 29 million (30% ) have postoperative complications

• GI or wound complications leading to…..…….longer stays, increase postoperative care and cost

• Most of these postop complications have been linked to:– Tissue Hypoperfusion

• One of the most important goals in the operating room is maintenance of adequate tissue perfusion

Gan et al., Lancet 1995 Guerrero et al., Anesth Analg 1999 Pearse et al., Crit Care 2006Weiser et al., Lancet 2008 Pearse et al., Lancet 2012 Suehiro et al., Curr Anesthesiol Rep 2014

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How Do You Achieve the Goal of Adequate Tissue Perfusion?

• By Optimization of intravascular fluid volume and stroke volume

• This produces:– Adequate cardiac output and perfusion pressure for

optimum Oxygen Delivery to the tissues

Oxygen Delivery Index (DO2I) =

Cardia Output x Blood Oxygen Content =

Body Surface Area

(SV x HR) X (1.34 ml O2 X Hgb X % Sat) / 100

m2

Suehiro et al., Curr Anesthesiol Rep 2014

Concept of Fluid Responsiveness:Recruitable Stroke Work

Principle: The cyclic effect of Mech. Vent. on left ventricular stroke volume (SV)

The magnitude of this effect is determined by the ventricular end diastolic volume (Preload) as defined by the Frank-Starling Curve

Preload (Ventricular End Diastolic Volume, mL)0

Fluid administration improves cardiac performance There is “recruitable cardiac ouput”

“Hypovolemia”

Further fluidhas no benefit“Hypervolemia” V

V

Maximum cardiac output“Euvolemia”

The Quantifiable Effect of Mechanical Ventilation on Pressure Waveforms

SPmax

SPmin

PPmax

PPmin

End Inspiration During Expiration

Pulse Pressure Variation (PPV) =(PPmax – Pmin)

(PPmean)

Systolic Pressure Variation (SP) = SPmax – SPminX 100

Airway Pressure

Arterial Pressure

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Preload Dependence - Optimization Concept

Preload (Ventricular End Diastolic Volume, mL)

Str

oke

Vo

lum

e (m

L)

0

V

Fundamental Algorithm for SV Optimization:Determining Fluid Responsiveness

SVIncrease

>10%

SVDecrease >10%

of Baseline

Challand et al. BJA 2011

Yes

New Baseline SV

No

NoYes

Case Study

• 49 Y/O, 63 kg Male for Nephrectomy

• History

– 1 PPD x 30 Years

– Past ETOH and Drug Use

– Normal ECG, EF 45%

• Mild Pulmonary Hypertension

– Systolic PAP = 40mmHg

• Moderate RV dysfunction

– Slight dilation

Cannesson M. Anesthesiology News. Part 1, 2011

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Case Study

• Monitoring Plan

– Hemodynamic Monitoring

Goal of Hemodynamic Monitoring

SVSVVScvO2

CO

SVV < 13%ScvO2 >75%

Max CO

Cannesson M. Anesthesiology News. Part 1, 2011

Case Study

• Anesthesia Plan

– Etomidate + Fentanyl Induction

– Fentanyl + Sevoflurane Maintenance

– 16 g Peripheral IV

– Baseline Crystalloid 5 mL/kg/hour

– Left Subclavian Central Venous Double-Lumen Catheter (ScvO2)

– Left Radial Art Line + Flotrac Sensor (SV,SVV, CO)

• SVV = SVMax – SVMin X 100

SVMean

Cannesson M., Anesthesiology News. Part 1, 2011

• 1 Hour into procedure

– BP: 85/47

– HR: 96

– EBL: 800 mL

– Hgb: 7.9 g/dL

• Intervention– 500 mL 6% HES

– 2 Units PRBC


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• Result of Fluid Bolus + PRBC

– BP: 98/57

– HR: 77

– Hgb: 10.7 g/dL

• Intervention

– Dobutamine

• 5 mcg/kg/min


• Result of Dobutamine Infusion – BP: 114/63

– HR: 82


Limitations of Dynamic Indices

• Four primary Limitations of use of Dynamic Indices

– Arrhythmias

– Tidal Volumes of < 8 ml / kg

– Marked decrease chest wall compliance

– Cor pulmonale

• Other issues

– Motion, and Cautery

Navarro et al., Perioperative Medicine 2015

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Navarro et al., Perioperative Medicine 2015

What Does the Literature Say: Perioperative Clinical Trials of GDFT (32 from 1995 to 2014)

Page 1

Page 5

Page 4Page 3

Page 2

Data Extraction:• Surgical Population • GDFT End Points• GDF Therapy• Control Protocol• Type of fluids• Control vs GDFT Management• Control vs GDFT Outcomes

Population by Surgical Procedure:• Major Bowel • Major Abdominal • Major Colorectal • Laparoscopic Colectomy• Cardiac / Bypass / On-Off Pump• Femoral Fx Repair / Total Hip• Major Elective • Moderate / High Risk Patients• Ovarian Cancer Cytoreduction

22 Studies (68%) Found Reduced Morbidity or Some Benefit of GDFT:

• Decreased postoperative complications:• Hypotension, PONV, cardiopulmonary, organ failure, infection rate

• Fewer ICU admissions / Shorter ICU stays• Reduced need for mechanical ventilation / Shorter use• Shorter HLOS

• Decreased gut mucosal hypoperfusion• More rapid recovery of gut function• Earlier oral intake

• Less intraoperative hypotension• Better intraoperative hemodynamic stability• Reduced need, shorter use, fewer adjustments for vasopressors•• Less need for transfusion of FFP • Lower serum lactate levels

10 of 32 Studies (31%) Found Increased Morbidity or No Benefit with GDFT:

• Increased pulmonary embolism (1)

• More use of inotropes (1)

• More postoperative complications (1)

• More blood loss and need for transfusion (1)

• Longer HLOS (1)

• No difference between groups (5)

“Individual clinical trials and meta-analyses have shown that different fluidtherapy regimens produce significantlydifferent clinical outcomes and haveresulted in considerable controversy asto the best approach.”

General Recommendations From the International Fluid Optimization Group

• Dynamic indices should be used as an integral part of GDFT protocols.

• For major surgery the use of a GDFT protocol containing colloids and balanced‐salt solutions is recommended.

• A perioperative fluid plan should be developed by each department, facility, or health system and used by all anesthesia providers.

• Fluid management algorithms should be used as part of the perioperative fluid plan.

Navarro et al., Perioperative Medicine 2015.

Final Thoughts

Perioperative fluid management remains a much debated issue

………..the data indicates that GDFT applied with the objective of hemodynamic optimization can reduce complications after major surgical procedures.

The best evidence to date suggest that high risks patients undergoing major surgical procedures should have fluid management titrated against some measure of cardiac output….

……….the ideal method to measure cardiac output and the best protocol to apply that information to optimize fluid therapy has yet to be determined.

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ERAS / GDFT References

• Benes J, Giglio M, Brienza N, Michard F. The effects of goal directed fluid therapy based on dynamic parameters on post surgical outcome: a meta-analysis of randomized controlled trials. Critical Care 2014; 18:584

• Berger MM, Gradwohl-Matis I, BrunauerA, Ulmer H, Dünser MW. Targets of perioperative fluid therapy and their effects on postoperative outcome: a systematic review and meta-analysis. Minverva Anestesiologica 2015; 81(7):794-808

• Biegner AR, Anderson D, Olson RL, Vacchiano CA. Quantification of insensible water loss associated with insufflation of nonhumidified CO2 in patients undergoing laparoscopic surgery. J Laparoendosc Adv Surg Tech A. 1999;9(4):325-329.

• Brandstrup B, Tonnesen H, Beier-Holgersen R, Hjortso E, Ording H, Lindorff-Larsen K, Rasmussen MS, Lanng C, Wallin L, the Danish Study Group on Perioperative Fluid Therapy (Kiversen LH, Gramkow CS, Okholm M, Blemmer T, Svendsen P, Rottensten HH, Thage, B, Riis J, Jeppesen IS, Teilum D, Christensen AM, Graungaard B, Pott F. Effects of intravenous fluid restriction of postoperative complications: comparison of two perioperative fluid regiments. Annals of Surgery 2003; 238(5):641-48

• Cannesson M, Guiding fluid management in the surgical setting. Anesthesiology News 2011; Part 1: 10-11.

• Challand C, Struthers R, Sneyd JR, Erasmus PD, Mellor N, Hosie KB, Minto G.Randomized controlled trial of intraoperative goal-directed fluid therapy in aerobically fit and unfit patients having major colorectal surgery. BJA 2011; 108(1):53-62

• Chappell D, Jacob M, Hofmann-Kiefer K, Conzen P, Rehm M. A Rational Approach to Perioperative Fluid Management. Anesthesiology. 2008;109(4):723-740. doi:10.1097/ALN.0b013e3181863117.

• Cecconi M, Corredor C, Arulkumaran N, et al. Clinical review: Goal-directed therapy-what is the evidence in surgical patients?The effect on different risk groups. Crit Care. 2013;17(2):209. doi:10.1186/cc11823.

• Corcoran T, Rhodes JEJ, Clarke S, Myles PS, Ho KM. Perioperative fluid management strategies in major surgery: a stratified meta-analysis. Anesthesia-Analgesia 2012; 114(3):640-51

• D'Angelo M, Hodgen RK, Wofford K, Vacchiano C. A Theoretical Mathematical Model to Estimate Blood Volume in Clinical Practice. Biol Res Nurs. October 2014:1099800414555410. doi:10.1177/1099800414555410.


• De Santis V, Singer M. Tissue oxygen tension monitoring of organ perfusion: rationale, methodologies, and literature review. Hardman JG, ed. British journal of anaesthesia. 2015;115(3):357-365. doi:10.1093/bja/aev162.

• Frost EAM. The rise and fall of the third space: appropriate intraoperative fluid management. Journal of the Medical Association of Thailand = Chotmaihet thangphaet. 2013;96(8):1001-1008.

• Gallagher K, Vacchiano, C. Reexamining traditional intraoperative fluid administration: evolving views in the age of goal-directed therapy. AANA J. 2014;82(3):235-242.

• Gan TJ, Soppitt A, Maroof M, El-Moalem H, Robertson KM, Moretti E, Dwane P, Glass PSA. Goal-directed intraoperative fluid administration reduces length of hospital stay after major surgery. Anesthesiology 2002; 97(4):820-26

• Gupta R, Gan TJ, World congress of enhanced recovery after surgery and perioperative medicine. Monograph, Washington, D. C. , 2015.

• Gustafsson UO, Scott MJ, Schwenk W, et al. Guidelines for perioperative care in elective colonic surgery: Enhanced Recovery After Surgery (ERAS®) Society recommendations. Clin Nutr. 2012;31(6):783-800. doi:10.1016/j.clnu.2012.08.013.

• Hahn RG, Bahlmann H, Nilsson L. Dehydration and fluid volume kinetics before major open abdominal surgery. Actaanaesthesiologica Scandinavica. 2014;58(10):1258-1266. doi:10.1111/aas.12416.

• Iijima T, Brandstrup B, Rodhe P, Andrijauskas A, Svensen CH. The maintenance and monitoring of perioperative blood volume. Perioper Med (Lond). 2013;2(1):9. doi:10.1186/2047-0525-2-9.

• Joosten A, Huynh T, Suehiro K, Canales C, Cannesson M, Rinehart J. Goal-directed fluid therapy with closed-loop assistance during moderate risk surgery using noninvasive cardiac output monitoring: a pilot study. BJA 2015; 114(6):886-92

• Keenan JE, Speicher PJ, Nussbaum DP, et al. Improving Outcomes in Colorectal Surgery by Sequential Implementation of Multiple Standardized Care Programs. J Am Coll Surg. 2015;221(2):404–414.e1. doi:10.1016/j.jamcollsurg.2015.04.008.

• Lamke LO, Nilsson GE, Reithner HL: Water loss by evaporation from the abdominal cavity during surgery.Acta Chir Scand 1977; 143:279-84

ERAS / GDFT References • Lilot M, Ehrenfeld JM, Lee C, Harrington B, Cannesson M, Rinehart J. Variability in practice and factors predictive of total crystalloid administration during abdominal surgery: retrospective two-centre analysis. British journal of anaesthesia. January 2015. doi:10.1093/bja/aeu452.

• MacDonald N, Ahmad T, Mohr O, Kirk-Bayley J, Moppett I, Hinds CJ, Pearse RM. Dynamic preload markers to predict fluid responsiveness during and after major gastrointestinal surgery: an observational a substudy of the OPTIMISE trial. BJA 2014;

• Marik PE, Cavallazzi R, Vasu T, Hirani A. Dynamic changes in arterial waveform derived variables and fluid responsiveness in mechanically ventilated patients: a systematic review of literature. Crit Care Med 2009; 37(9): 2642-47

• Marik PE, Monnet X, Teboul J-L. Hemodynamic parameters to guide fluid therapy. Ann Intensive Care. 2011;1(1):1. doi:10.1186/2110-5820-1-1.

• Mayer J, Boldt J, Mengistu AM, Röhm KD, Suttner S. Goal-directed intraoperative therapy based on autocalibrated arterial pressure waveform analysis reduces hospital stay in high risk surgical patients: a randomized, controlled trial. Critical Care 2010; 14:R18

• Michard F, Teboul J-L. Predicting fluid responsiveness in ICU patients: a critical analysis of the evidence. Chest. 2002;121(6):2000-2008.

• Miller TE, Roche AM, Gan TJ. Poor adoption of hemodynamic optimization during major surgery: are we practicing substandard care? Anesth Analg. 2011;112(6):1274-1276. doi:10.1213/ANE.0b013e318218cc4f.

• Minto G, Mythen MG. Perioperative fluid management: science, art or random chaos? British journal of anaesthesia. March 2015. doi:10.1093/bja/aev067.

• Monnet X, Pinsky MR. Predicting the determinants of volume responsiveness. Intensive Care Med. 2015;41(2):354-356. doi:10.1007/s00134-014-3637-5.

• Muller L, Brière M, Bastide S, et al. Preoperative fasting does not affect haemodynamic status: a prospective, non-inferiority, echocardiography study. British journal of anaesthesia. February 2014. doi:10.1093/bja/aet478.

• Navarro LHC, Bloomstone JA, Auler JOC, et al. Perioperative fluid therapy: a statement from the international Fluid Optimization Group. Perioper Med (Lond). 2015;4(3):1-20. doi:10.1186/s13741-015-0014-z.

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• MacDonald N, Ahmad T, Mohr O, Kirk-Bayley J, Moppett I, Hinds CJ, Pearse RM. Dynamic preload markers to predict fluid responsiveness during and after major gastrointestinal surgery: an observational a substudy of the OPTIMISE trial. BJA 2014;

• Marik PE, Cavallazzi R, Vasu T, Hirani A. Dynamic changes in arterial waveform derived variables and fluid responsiveness in mechanically ventilated patients: a systematic review of literature. Crit Care Med 2009; 37(9): 2642-47

• Marik PE, Monnet X, Teboul J-L. Hemodynamic parameters to guide fluid therapy. Ann Intensive Care. 2011;1(1):1. doi:10.1186/2110-5820-1-1.

• Mayer J, Boldt J, Mengistu AM, Röhm KD, Suttner S. Goal-directed intraoperative therapy based on autocalibratedarterial pressure waveform analysis reduces hospital stay in high risk surgical patients: a randomized, controlled trial. Critical Care 2010; 14:R18

• Miller TE, Roche AM, Gan TJ. Poor adoption of hemodynamic optimization during major surgery: are we practicing substandard care? Anesth Analg. 2011;112(6):1274-1276. doi:10.1213/ANE.0b013e318218cc4f.

• Minto G, Mythen MG. Perioperative fluid management: science, art or random chaos? British journal of anaesthesia. March 2015. doi:10.1093/bja/aev067.

• Monnet X, Pinsky MR. Predicting the determinants of volume responsiveness. Intensive Care Med. 2015;41(2):354-356. doi:10.1007/s00134-014-3637-5.

• Muller L, Brière M, Bastide S, et al. Preoperative fasting does not affect haemodynamic status: a prospective, non-inferiority, echocardiography study. British journal of anaesthesia. February 2014. doi:10.1093/bja/aet478.

• Navarro LHC, Bloomstone JA, Auler JOC, et al. Perioperative fluid therapy: a statement from the international Fluid Optimization Group. Perioper Med (Lond). 2015;4(1):3. doi:10.1186/s13741-015-0014-z.


• Waldron NH, Miller TE, Thacker JK, Manchester AK, White WD, Nardiello J, Elgasim MA, Moon RE, Gan TJ. A prospective comparison of a noninvasive cardiac output monitor versus esophageal doppler monitor for goal-directed fluid therapy in colorectal surgery patients. Anesthesia-Analgesia 2014; 118(5):966-75

• Wilms H, Mittal A, Haydock M, van den Heever M, Devaud M, Windsor J. A systematic review of goal directed fluid therapy: rating of evidence for goals and monitoring methods. Journal of Critical Care 2014; 29:204-09

• Wythe S, Hanison J, Lund K, et al. Does fasting time alter fluid responsiveness after induction of anaesthesia? British journal of anaesthesia. 2015;114(3):533-533. doi:10.1093/bja/aev025.

goal directed fluid therapy: fact, fiction, findings and the future

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