application hlm/ecc Flashcards
Describe the preparation of the tubic system.
flushing followed by priming
What is a flush?
flushing of the tube system with CO2 or N2 which are then easier removed by the priming solution -> reduction of air bubbles
Explain priming.
fill the EEC tubes setup and circulate with a special priming solution including: ringer solution + buffer + osmotic solution (like Albumin) + Heparin + drugs
- 2000-700 IE Heparin
- 2-2.5 liter priming volume
- dilution -> viscosity and coagulation reduced
What effect does priming have on various values?
all reduced
What jobs do the pumps have during ECC with HLM?
arterial: transports the blood from the venous reservoir through the oxygenator back to the patient
vent: pumps blood from left ventricle back to cardiotomy reservoir
cardioplegia: used to administer cardioplegia solution
sucker: remove blood from the operation area and recirculat it via cardiotomy reservoir
How is the pump volume determined?
adults: body surfacearea * 2.4
infants: body surfacearea * 2.6
surfacearea = weight * height
Which procedure causes the highest blood damage?
the sucker line, because the pump sucks a lot of air which results in foaming
What is the meaning of the vent catheter?
The vent catheter is inserted in the left ventricle through the left atrium, it sucks the blood coming from the branchio pulmonary shunt and tebesian veins and sends it to the cardiotomy reservoir
Describe the structure of an aortic cannula.
has a straight or bend tip, made of PVC or other polymere
softflow tip to reduce jet streams in aorta
What is a two stage cannula?
a venous cannula with two inelts, allowing to simultaneously drain blood from the vci (dorsal inlet) and rA (proximal) using only one cannula
is used for partial bypass
Describe the cannulation for a coronary bypass operation.
-> partial bypass
aortic cannulation:
aorta ascendence
venous cannulation:
two-stage cannula:
inserted through right appendix, dorsal end in vci and proximal and in rA
Describe the cannulation for an aortic valve operation.
-> total bypass
aortic cannulation:
aorta ascendence
venous cannulation:
two single stage cannulas
- cvs through right appendix
- cvi through wall of rA
What is cross clamping?
the aorta is being clamped completely, resulting in a total bypass
What is a partial/total bypass?
total: flow entirely reliant on the heart lung machine, aorta and veins are clamped
partial: bloodflow can pass the cannulas, no clamps
Which vessels are best used for bypasses?
arteries are best used, like the arteria mamaria interna or veins like the vena saphena magma or vena radialis
