CONDUCT OF CONDUCT OF PERFUSIONPERFUSION
October 16, 2003October 16, 2003
Brian Schwartz, CCPBrian Schwartz, CCP
PURPOSE OF CPBPURPOSE OF CPB
• PROVIDE SURGEONS WITH A MOTIONLESS AND BLOODLESS FIELD
• PROVIDE PROTECTION TO VITAL ORGAN SYSTEMS
Your ObjectivesYour Objectives
• Understand the components of the CPB circuit
• Understand the sequence for assembly of the circuit
• Able to calculate the predicted hemoglobin and hematocrit
• Understand the determinants of oxygen consumption
Conduct of Perfusion Conduct of Perfusion
• Purpose of CPB: support patient’s metabolic needs while providing a motionless, bloodless cardiac surgical field
• Parameters that must be met:• Proper flow rate • Oxygen delivery • Carbon dioxide removal • Anticoagulation • Temperature • Blood pressure • Blood recovery
Components of the CPB CircuitComponents of the CPB Circuit
• Oxygenator • Heat exchanger • Venous reservoir • Gas flow meter • Variety of pumps • Tubing • Cannulae • Hemoconcentrator • Alarms• Drugs
Assembly Assembly
• The set up is dependent upon:• Procedure • Patient size• Surgeon’s preference• Perfusionist’s preference
CONDUCT OF PERFUSIONCONDUCT OF PERFUSION
• WE ARE TALKING ABOUT OUR DUTIES AND RESPONSIBILTIES PRE-OP, INTRA-OP, AND POST-OPERATIVELY
THE PERFUSIONIST’S TIME LINETHE PERFUSIONIST’S TIME LINE
• GET A HANDLE ON THE SCHEDULE
• REVIEW PATIENT’S CHART
• SELECTION OF DISPOSABLE EQUIPMENT
• ASSEMBLE HLM
• PLUG IN POWER AND GAS LINES
• PLUG IN HEATER/COOLER (WATER TEST)
Time Line (cont)Time Line (cont)
• CO2 flush the circuit
• Prime the circuit
• Test all occlusions
• Check list
• Perform all quality controls
• ALWAYS BE PROPARED TO GO ON CPB
TIME LINE (CONTINUED)TIME LINE (CONTINUED)
• PRIME CIRCUIT
• PERFORM CHECK LIST
• ADMINISTRATION OF HEPARIN
• INITIATION OF CPB
• TERMINATION OF CPB
• ADMINISTRATION OF PROTAMINE
• BREAKDOWN AND CLEANUP OF HLM
PRE-BYPASS CALCULATIONSPRE-BYPASS CALCULATIONS
• PREDICTED HEMATOCRIT– 70 X KG = TBV– TBV X HCT = TRBC– TBV + PRIME + ANES. DRIPS = TCBV– TRBC/RCBV = DILUTIONAL HCT
PRE-BYPASS CALCULATIONSPRE-BYPASS CALCULATIONS
• HCT IF SEQUESTERING BLOOD– TRBC – { 500 cc x HCT } / TCBV – 500 cc
HEPARIN ADMINISTRATIONHEPARIN ADMINISTRATION
• DESCRIBED AS AN ANTICOAGULANT
• MUST FULLY ANTICOAGULATE PATIENT
• SITE OF ACTION: ATlll AND INHIBITS FACTORS IX AND XI OF THE CLOTTING CASCADE
• GIVE 300-400 UNITS/KG– IN RIGHT ATRIUM OR CENTRAL LINE
HEPARIN ( CONTINUED )HEPARIN ( CONTINUED )
• HALF LIFE = 1-2 HOURS
• 3-5 MINUTES AFTER ADMINISTERING TAKE AN ACT…..MUST BE >480 SECONDS
• SOME PATIENTS MAY BE HEPARIN RESISTENT– THEY ARE ATIII DEFICIENT– GIVE FRESH FROZEN PLASMA
CANNULATIONCANNULATION
• SURGEONS NOW PLACE THE CANNULAE INTO THE HEART
• VENOUS CANNULAE– IN RIGHT ATRIUM WITH 2 STAGE – SINGLE STAGE IN THE IVC AND THE SVC
CANNULATION CANNULATION
• ARTERIAL CANNULAE– AORTA OR FEMORAL ARTERY
• RETROGRADE CARDIOPLEGIA
• ANTEGRADE CARDIOPLEGIA
• VENT
PURPOSE OF VENTPURPOSE OF VENT
• PLACED IN THE AORTIC ROOT OR IN THE LEFT VENTRICLE
• USED TO PREVENT DISTENTION OF THE HEART
• USE A ONE-WAY VALVE
INITIATION OF BYPASSINITIATION OF BYPASS
• SURGEONS READY TO BEGIN CPB. THEY WILL TELL YOU TO “GO ON”– ALWAYS REPEAT COMANDS BACK TO
AVOID MISTAKES
• PUT 02 ON 100%, SWEEP ON, REMOVE ARTERIAL CLAMP, SLOWLY TURN PUMP ON. CAREFULLY MONITOR ARTERIAL LINE PRESSURE !!!!!!!!
BYPASSBYPASS
• UNCLAMP VENOUS LINE AND INCREASE FLOW TO YOUR 2.4 INDEX
• IF YOU SENSE A HIGH LINE PRESSURE AS YOU INITIATE BYPASS…IMMEDIATELY TERMINATE BYPASS!!!!!!
CAUSES OF HIGH AORTIC LINE CAUSES OF HIGH AORTIC LINE PRESSUREPRESSURE
• KINK IN THE A-LINE• CANNULAE IMPROPERLY POSTIONED• CROSS-CLAMP TOO CLOSE TO
CANNULAE• ARTERIAL CANNULAE TOO SMALL• SYSTEMIC PRESSURE TOO HIGH• AORTIC DISECTION• ARTERIAL FILTER OBSTRUCTED
CAUSES OF POOR VENOUS CAUSES OF POOR VENOUS RETURNRETURN
• KINK IN VENOUS LINE OR CANNULA
• AIRLOCK
• OXYGENATOR IS NOT POSITIONED LOW ENOUGH
• VENOUS CANNULA PLACED TO FAR DOWN INTO THE CAVA
• VENOUS CANNULA FALLS OUT
CHATTERINGCHATTERING
• A TERM USED IF THE HEART IS COMPLETELY EMPTY AND YOU SEE THE VENOUS LINE JUMPING AROURD
• CHATTERING IS CAUSED BY EXCESSIVE NEGATIVE PRESSURE IN THE VENOUS LINE CAUSING A SUCTION EFFECT….SIMPLY PLACE A CLAMP (PARTIALLY) ON THE VENOUS LINE TO REDUCE THE NEGATIVE PRESSURE
SAFTEY CHECKS TO DO ON SAFTEY CHECKS TO DO ON BYPASSBYPASS
• FLOWING AT PROPER RATE• A-LINE PRESSURE IN NORMAL• OXYGEN IS ON AND THAT ARTERIAL BLOOD
IS RED….COMPARE A/V LINES• O2 SAT’S NORMAL• MAP BETWEEN 50-70 • TEMP’S• ACT>480• MAKE SURE ALL SAFETY DEVICES ARE ON
MONITORINGMONITORING
• EKG– WHILE THE CROSS-CLAMP IS ON THERE
SHOULD BE NO ACTIVITY– WHEN CLAMP COMES OFF, BE ON THE LOOK
OUT FOR ST ELEVATIONS, V-TACH, AND V-FIB
• PA PRESSURES• CIRCUIT• OPERATING TEAM• KEEP COMMUNICATION OPEN• TRAFFIC AROUND PUMP
CHARTINGCHARTING
• VITAL SIGNS MUST BE TAKEN EVERY 15 MINUTES
• ACT’S MUST BE TAKEN EVERY 30 MIN• BLOOD GASES MUST BE TAKEN EVERY 30
MINUTES OR AFTER CHANGES HAVE BEEN MADE– FIRST BLOOD GAS SHOULD BE TAKEN 5-10
MINUTES AFTER CPB– DON’T FORGET TO GET A WARM GAS BEFORE
TERMINATING BYPASS
NORMAL ARTERIAL GASNORMAL ARTERIAL GAS
• pH: 7.35-7.45
• p02: Greater than 100
• 02 Sat: 96-100%
• K+: 3.5-5.3
• BICARB: 22-28 MEQ/L
• BE: -2.5 TO + 2.5
NORMAL VENOUS GASNORMAL VENOUS GAS
• pH: 7.35-7.39
• P02: 38-42
• 02 Sat: 65-75%
• pCO2: 44-48mmHG
• Bicarb: 22-28 mmHG
• BE: -2.5 to +2.5
Determine Oxygen ConsumptionDetermine Oxygen Consumption
• Oxygen content=1.34 x Hb x Sat + .003xp2
• Oxygen Capacity =1.34 x Hb + .003 x pO2
• Oxygen Saturation = O2 content/ Capacity• Oxygen Consumption= aO2 content – vO2 content x
flow (L/min) X 10
CALCULATE AMOUNT OF CALCULATE AMOUNT OF BICARB TO GIVEBICARB TO GIVE
1. WT (KG) X BASE DEFICIT X .3
2. EQUATION #1 DIVIDED BY 2 = AMOUNT OF BICARB TO GIVE
EXAMPLE: 70 X 3 X .3 = 63
63 / 2 = 32 mEq
POST BYPASSPOST BYPASS
• MONITOR PATIENTS HEMODYNAMICS
• NEVER DISMANTLE PUMP UNTIL CHEST IS CLOSED
• PROTAMINE• MANY PATIENTS HAVE REACTION• TURN OFF PUMP SUCKERS• MONITOR PA AND MAP
PROTAMINE REACTIONSPROTAMINE REACTIONS
• TYPE I– SYSTEMIC HYPOTENSION– REDUCED SVR
• TYPE II– ANAPHYLACTIC REACTION RESULTING IN
HYPOTENSION, BRONCHOSPASM, AND EDEMA
• TYPE III– CATASTROPHIC PULMONARY
VASOCONSTRICTION WITH INCREASED PA PRESSURES, HYPOTENSION, DECREASED LA PRESSURES, AND DILATED RIGHT VENTRICLE