PiCCO – PULSE induced CONTOUR CARDIAC OUTPUT

Indications in ICU

Haemodynamic instability

Shock (cardiogenic shock)

Sepsis

Lung injury

Pulmonary oedema

Organ failure

Cardiogenic shockThe haemodynamic profile of low cardiac output, hypotension and severe pulmonary congestion arising from an acute disturbance in cardiac function is termed cardiogenic shock.

Specific definition of cardiogenic shock includes:- Cardiac index less than 2.1 Systolic blood pressure less than 90 Pulmonary capillary wedge pressure greater than 18 Additional parameters include Intra-thoracic blood volume index greater than 850 Global end diastolic volume greater than 700 Extra vascular lung volume index greater than 10.

Contraindications for PiCCO can classified under 2 categories

Contraindication to vascular device insertion including peripheral vascular disease, arterial grafting, overlaying infection and coagulopathy

Anatomical or physiological derangements such as patients having constant cardiac arrhythmias , aortic valve pathology

Others :- patients on circulatory assist device unreliable arterial waveform (positional)

PARAMETERS MEASURED IN PiCCO

Stroke volume

Based on the demographic data and arterial waveform details an individual calibration factor is computed as the automatic start value – CO. Then pulmonary contour analysis is performed

from the arterial pressure curve. Stroke volume is analysed and calibrated by comparing the systolic area with the start value -CO

Stroke Volume is reflected by the area under the systolic part of the pressure

curve (red area) of one heart beat.

Stroke volume

Stroke volume is the amount of blood ejected by the right ventricle in one contraction. It is calculated using the following formula

Stroke volume (SV) = (Cardiac output x 1000) / Heart rate

For example, patient with a hear rate of 75beats/minute and cardiac out put of 5litres / minute stroke volume is calculated as below

SV = (5 X 1000) / 75 = 66.67ml/beat

Stoke volume variation - SVV

Changes in stroke volume over the respiratory cycle

SVV should be less than 10%. High SVV triggers fluid resuscitation.

SVV are only applicable in patients on

fully controlled mechanical ventilation and in regular rhythm with tidal volume at least 8ml/kg.

Cardiac Index

Volume of blood pumped by the heart in one minute indexed to body surface area.

CI = 3 – 5 l/min/m2

Stoke volume index

Volume pumped by the heart during one heart beat indexed to BSA

SVI = 40 – 60 ml/m2

GEDVI – global end diastolic volume index

Volume of blood contained in the four chambers of the heart indexed to BSA.

GEDVI – 680 – 800 ml/m2

Intra-thoracic blood volume index

Volume of blood contained in the four chambers of the heart plus blood volume in the pulmonary blood vessels indexed to BSA.

ITBVI – 850 – 1000 ml/m2

Extra vascular lung water index

The amount of water content in the lungs; allows quantification of the degree of pulmonary oedema

EVLWI – 3 – 7ml/kg.

SVRI = 1700 to 2400 dyn x sec x cm-5 x m2

Systemic vascular resistance indexResistance the heart has to overcome to eject blood.

SVRI helps to differentiate and optimize vasopressor therapy.