Why measure cardiac output in critically ill children?

Radboud University NijmegenMedical Centre

J. LemsonAnesthesiologist/(pediatric)intensivist

Why measure cardiac output incritically ill children?

Case; Girl 2 years, 12 kg, severe meningococcal septic shock

PO2 11.2 kPa (100% O2)pH 7.03BE -20 mmol/lLactate 5.8 mmol/lHR 180 bpmMAP 60 mmHgRefill

CI 6.5 l/min/m2

Case; Girl 2 years, 12 kg, severe meningococcal septic shock

PO2 11.2 kPa (100% O2)pH 7.03BE -20 mmol/lLactate 5.8 mmol/lHR 180 bpmMAP 60 mmHgRefill

Hemodynamic monitoring in Brussels 2007 (adults)

Hemodynamic monitoring Geneva 2007

Lancet 2005; 366: 472–77

The Pulmonary Artery Catheter (PAC)

“…. our trial was never sufficiently powered to compare managementwith a PAC against no cardiac output monitoring”

=> Not all PAC trials concern cardiac output measurement itself!

PAC in children

Courtesy of dr. Jeroen Verwiel

The use of the PAC is not advised in (small) children

CO measurement; less invasive techniques

Fick• O2• CO2 (NICO2)Doppler• pre sternal/jugulum (UScom)• oesophageal (CardioQP / Hemosonic)

Dilution technique• Transpulmonary lithiumdilution (LidCO)• Transpulmonary thermodilution (PiCCO)• Transpulmonary ICG dilution (DDG analyser)

Arterial Pulse contour analysis• PiCCO• LidCO (PulseCO)• Modelflow• PRAM• FlowTrac

EchocardiographyBioimpedance

Controlled variable (baroreflex) PreloadAfterloadContractility

Basic haemodynamics

preload

SV

Basic haemodynamics

Normal contractility

Decreased contractility

Decreased myocardial contractility => decreased “margin of preload”

Crit Care Med 2002; 30:2191–2198

Septic cardiomyopathy

Effects of normal and meningococcal serum on rat myocyte contraction amplitude.

Inflammation

Pediatr Crit Care Med 2003; 4:299 –304

Neonates and infants undergoing congenital cardiac surgery usingcardiopulmonary bypass.

Patients undergoing CPB with neonate or infants group.

Eur J of Cardio-thoracic Surg 1997; 12: 862–868

Inflammation

Crit Care Med 2007; 35:1599 – 1608

Inflammation

Inflammation

Sepsis

Surgery / Trauma

Myocardial dysfunctionIncreased capillary permeabilityVasodilation

Autonomic dysregulation

Cardiovascular Research 2007;73:26–36

(Younger children more susceptible ?)

Arch Dis Child 1997;77:516–518

Clinical estimation of cardiac output

Heart rate and cardiac output

N = 11; Newborn animal modelFluid resuscitation (10 ml/kg) from hypovolemic shock

R2 = 0,0213

-100

-50

0

50

100

150

200

250

-30 -20 -10 0 10 20 30

HR (%)

cardiacoutput(%)

J. Lemson et al; accepted Ped Crit Care Med 2007

J. Lemson et al. Europediatrics 2006

R2 = 0,2446

-3

-2

-1

0

1

2

3

-60 -40 -20 0 20 40

HR (bpm)

cardiacindex(l/min/m

2 )

N = 13; critically ill children (2 months - 8 years)

Heart rate and cardiac output

-120

-100

-80

-60

-40

-20

0

20

40

60

-40 -30 -20 -10 0 10 20 30 40

delta CO (%)

deltaMAP(%)

-120

-100

-80

-60

-40

-20

0

20

40

60

-40 -30 -20 -10 0 10 20 30 40

delta CO (%)

deltaMAP(%)

MAP and cardiac output

J. Lemson et al. Europediatrics 2006

N = 13; critically ill children (2 months - 8 years)

n = 15; age 3 – 264 hoursEffect of 20 ml/kg fluid loading

Before After p-value

HR (bpm) 140 (125–164) 139 (119–187) NS

MAP (mmHg) 33 (22–40) 37 (31–60) < 0.005

CI (ml/min/kg) 295 (134–376) 323 (182–382) < 0.01

FS (%) 33 (23–40) 32 (23–44) NS

Int Care Med 1997;23:982-986

Stroke volume and cardiac output

-50

0

50

100

150

200

-100 -50 0 50 100 150 200 250

delta CO (%)

delta

SV(%)

-50

0

50

100

150

200

-100 -50 0 50 100 150 200 250

delta CO (%)

delta

SV(%)

J. Lemson et al; accepted Ped Crit Care Med 2007

Stroke volume and cardiac output

N = 11; Newborn animal modelFluid resuscitation (10 ml/kg) from hypovolemic shock

JAMA 1991;266:1242-1245

• 34 patients (median age 13.5 months) with septic shock.• Rapid fluid resuscitation in excess of 40 mL/kg in the first hour followingemergency department presentation was associated with improvedsurvival…..

Give enough fluids….

N Engl J Med 2001;345:1368-1377

Early goal directed therapy (“Rivers study”)

Chest 2005;128;3098-3108

Variables Odds Ratio (95% Confidence Interval)Cancer 4.4 (1.6–12.1)High tidal volume 2.3 (1.2–4.4)Mean SOFA score 1.4 (1.3–1.6)Mean fluid balance 1.5 (1.1–1.9)

3147 adult patients with acute lung injury

Sepsis Occurrence in Acutely Ill Patients (SOAP) network in 24 European countriesduring a 14-day period from May 1, 2002, to May 15, 2002.

But not to much! …..

Kidney International, 2005;67:653–658

Higher fluid balance => higher mortality

Variable Survivors Non-survivors p value

Patient age (years) 8.49 ± 6.74 8.51 ± 7.19 NS

PRISM 2 at PICU admit 14.3 ± 8.2 16.2 ± 9.7 NS

Fluid overload (%) 14.2 ± 15.9 25.4 ± 32.9 <0.03

116 children with MODS requiring renal replacement therapy

Fluid resuscitation

increase preload cardiac output

“fluid responsive”

Fluid resuscitation

increase preload cardiac output =

risk of fluid “overloading”

Neth J Med 2000;57:82-93Acta Anaesthesiol Scand 2004;8:69-73

Fluid resuscitation

increase preload cardiac output

“fluid responsive”Fluid responsiveness adults• Arterial pressure variation• Global end diastolic volume (GEDV)• Passive leg raising• etc

Fluid resuscitation

increase preload cardiac output

“fluid responsive”Fluid responsiveness children?????????

?

1. Clinical parameters, heart rate and blood pressure do notreflect changes in cardiac output

2. Cardiac output measurement is the cornerstone inhaemodynamic management of children

3. Advanced hemodynamic monitoring could be beneficial

Conclusion

Radboud University NijmegenMedical Centre

PiCCOplus

Calorimeter(Fick)

NICO2

USCom

COLD

CCO (PAC)

BoMed

CardioQP

PiCCO

What’s it all about?

What’s it all about?

“No monitoring device, no matter how simple or sophisticated, willimprove patient-centered outcomes unless coupled with a treatment that,itself, improves outcome……”

Pinsky & Vincent

Crit Care Med 2005;33:1119-1122

The author has no financial or other relationship that might leadto a conflict of interest

Statement

[email protected]

Radboud University NijmegenMedical Centre