of C.O. with a right heart catheter is done using thermodilution technique,
where temperature is the detected change.
a predetermined amount of fluid, at a known T., into C.V.P. port provides
the temperature change/change in time signal that the computer analyzes
to calculate CO.
outputs are measured using 10 mL of 6-12oC D5W. Variations in volume, catheter,
or temperature may require a change to the constant used (see chart for
cardiac output constants).
depending on volume used, catheter type, and temperature of injectate.
you have the CO-Set for cold cardiac output measurements.
for cold is a different circuit than the room temperature set up.
|4.Pack the container
with crushed ice up to the inside ridge in the internal ribs.
||4.It is difficult
to put ice in this section when the coils are in place.
|5.Place the cooling
coil on the first ridge in the styrofoam container. Be sure that the white
plastic square is inside the container.
of the coil will allow D5W to cool to the appropriate temperature as it
flows through the tubing.
cover the cooling coil with crushed ice.
||6.To cool the
D5W to 6-12oC.
|7.Add COLD water
until it is visible above the ice level.
||7.To make ice
slush solution for cooling D5W.
|8.Place any unused
length of tubing coil into the ice container. The 500 ml bag of D5W must
be on the outside of the container.
additional cold solution. The D5W will be too cold if the 500 ml bag is
in the container.
|9.Lock the lid
on the cooling container. (You should be able to read "CO-Set" on the lid
when it is properly placed).
*Note: use the
spigot to drain excess water from the melting ice before refilling.
|9.A covered ice
bath should remain useable for up to 6 hours. Check periodically to ensure
ice is still present.
should reach operating temperature within 5 minutes.
to sit a minimum of 5 minutes before injection.
that an order has been written. (Preprinted standard orders apply)
||11.An order is
required to perform this test.
infusing into injection port.
infusions that support CO or BP, should not be infused via injection port.
The nurse MAY NOT perform cardiac output measurements in this case.
and obtain remaining H.D. measurements before doing C.O. (C.V.P. and wedge).
||13.PWP may be
transiently higher post injections. Consistency in measurement technique
is important when interpreting results.
|14.Be aware that
very rapid (more than 100 mL/hour) infusions into any other ports may alter
temperature may be decreased by rapid infusion of room temperature I.V.
solutions and the change in temperature may not be enough for the thermistor
cardiac outputs, establish that the right heart catheter shows a good pulmonary
done with improper position of right heart catheter may yield inaccurate
|16.Perform hand hygiene. Don non-sterile gloves when drawing blood samples.
||16.In accordance with the MoHLTC 4 moments of hand hygiene and LHSC infection control policies.
module into Datex monitor and clip the injectate temperature probe
to Closed Injectate flow-through housing (see diagram).
Touch "CO/wedge/SvO2" button on
|17.This is the
interface for information transfer from the catheter to the monitor.
constant is correct according to type of catheter, volume used, and injectate
is essential to ensure computer "knows" the length from C.V.P. port to
distal tip, the temperature drop and dilution. Wrong constants will cause
|19.Turn CVP injectate
port infusions off.
sits between the injectate and patient. Any variation between the temperatures
of the CVP infusion and the cardiac output injectate would alter temperature
after injectate temperature is measured.
D5W line of the Closed Injectate Delivery System.
begin automatically upon release of clamp.
mL of D5W into the syringe. Close the clamp as soon as filling is complete.
Note: if you pull
back on the syringe plunger too hard the plunger can actually be pulled
out of the syringe. Be careful not to over fill.
|21.When the clamp
is opened, the syringe will continue to fill.
D5W is the required
solution because calculation of cardiac output is based on the specific
gravity and temperature of blood, and specific gravity and temperature
of D5W (NaCl has a different specific gravity).
A one way valve
prevents aspiration of blood or backward flow during syringe filling.
|22.Press start CO.Inject when monitor displays "Inject Now".
as exhalation begins. If the patient is receiving any mechanical ventilation,
perform the injection with a mechanical breath.
minimal variation related to different phases of the respiratory cycle.
Venous return and filling pressures change at various points of the respiratory
cycle. Mechanical breaths will have the greatest influence.
inject entire syringe volume using a steady, continuous pressure. Deliver
contents within 4 seconds.
delivery is necessary to produce an accurate temperature change curve.
of cardiac output depends on the difference between patient's blood temperature
and injectate temperature.
take place in order to detect temperature accurately.
the temperature of the injectate is between 6-12oC.
temperature is within range.
minimum of 3 measurements and obtain the average.
approximately 1 minute apart.
Discard all samples
with a variance of more than 10% from other measurements.
with a poor quality curve by editing, then averaging results. Remove inaccurate CO by scrolling to "Edit results", once this is complete press "average all", then it will ask you to press "confirm".
minute between injections permits blood temperature to return to normal
To prevent averaging in inaccurate results.
Flow-Through temperature probe from the housing.
damage to cable during patient turning etc.
|29.Open IV stopcock
and restore infusion rate.
IV therapy resumes and line patency is maintained.
tracing is present on monitor when completed.
catheter placement has not been altered.
|31. Remove non-sterile gloves and perform hand hygiene.
||31. In accordance with the MoHLTC 4 moments of hand hygiene and LHSC infection control policies.
measurements are important when calculations for oxygen extraction, O2
delivery, and O2 consumptions are done. Oxygen delivery for example is
calculated as C.O. x Arterial Oxygen Content, the assumption is that all
factors in the equation reflect the same time and condition.
Hb does not change very quickly. Hb is needed to calculate oxygen content
and therefore any values using oxygen content.
Lactates are invalid
if a tourniquet is applied as the distal limb would produce increased lactic
and arterial gases, lactate and Hb. Both gases must be drawn within 5 minutes
of cardiac output measurement. The same conditions must exist during cardiac
output and blood gas measurements (ie. head of bed at same level, same
oxygen concentration and same amount of ventilation).
bleeding, the Hb should be drawn within 4 hours of the Cardiac output measurement.
The lactate should
be drawn within 4 hours of the cardiac output measurement. Either an arterial
or venous lactate may be sent. Venous lactates must be drawn from an indwelling
catheter (no tournequet).
using B.S.A. guide.
standardizes the body surface area so that the normal range for CI is the
same for all patients.
||34.FI02 is needed
for the computer to calculate shunt (QS/QT).
collected data into the CCTC computer program
will calculate the pre-programmed equations for the desired hemodynamic
variables and oxygen transport indices.
the data you have entered on the hemodynamic profile for typographical
of the values are calculated by the entered information, incorrect data
will result in multiplied errors for the calculated values.
|37.Have the results
reviewed by the physician.
therapy and communicate results.
on the back of the physician's clinical notes and record appropriate hemodynamic
data onto flowsheet.
and communicate data.
|39.Be sure you
have signed the hemodynamic profile.
person who took the measurements.