CONDUCT OF PERFUSION October 16, 2003 Brian Schwartz, CCP

PURPOSE OF CPB PROVIDE SURGEONS WITH A MOTIONLESS AND BLOODLESS FIELD PROVIDE PROTECTION TO VITAL ORGAN SYSTEMS

Your 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 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 Circuit Oxygenator Heat exchanger Venous reservoir Gas flow meter Variety of pumps Tubing Cannulae Hemoconcentrator Alarms Drugs

Assembly The set up is dependent upon: Procedure Patient size Surgeon’s preference Perfusionist’s preference

CONDUCT OF PERFUSION WE ARE TALKING ABOUT OUR DUTIES AND RESPONSIBILTIES PRE-OP, INTRA-OP, AND POST-OPERATIVELY

THE 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) 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) PRIME CIRCUIT PERFORM CHECK LIST ADMINISTRATION OF HEPARIN INITIATION OF CPB TERMINATION OF CPB ADMINISTRATION OF PROTAMINE BREAKDOWN AND CLEANUP OF HLM

PRE-BYPASS CALCULATIONS PREDICTED HEMATOCRIT –70 X KG = TBV –TBV X HCT = TRBC –TBV + PRIME + ANES. DRIPS = TCBV –TRBC/RCBV = DILUTIONAL HCT

PRE-BYPASS CALCULATIONS HCT IF SEQUESTERING BLOOD –TRBC – { 500 cc x HCT } / TCBV – 500 cc

HEPARIN ADMINISTRATION DESCRIBED AS AN ANTICOAGULANT MUST FULLY ANTICOAGULATE PATIENT SITE OF ACTION: ATlll AND INHIBITS FACTORS IX AND XI OF THE CLOTTING CASCADE GIVE UNITS/KG –IN RIGHT ATRIUM OR CENTRAL LINE

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

CANNULATION 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 ARTERIAL CANNULAE –AORTA OR FEMORAL ARTERY RETROGRADE CARDIOPLEGIA ANTEGRADE CARDIOPLEGIA VENT

PURPOSE 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 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 !!!!!!!!

BYPASS 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 PRESSURE 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 RETURN 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

CHATTERING 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 BYPASS 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 TEMP’S ACT>480 MAKE SURE ALL SAFETY DEVICES ARE ON

MONITORING 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

CHARTING 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 GAS pH: p02: Greater than Sat: % K+: BICARB: MEQ/L BE: -2.5 TO + 2.5

NORMAL VENOUS GAS pH: P02: Sat: 65-75% pCO2: 44-48mmHG Bicarb: mmHG BE: -2.5 to +2.5

Determine Oxygen Consumption Oxygen content =1.34 x Hb x Sat +.003xp2 Oxygen Capacity = 1.34 x Hb x pO2 Oxygen Saturation = O2 content/ Capacity Oxygen Consumption= aO2 content – vO2 content x flow (L/min) X 10

CALCULATE AMOUNT OF BICARB 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 = / 2 = 32 mEq

POST 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 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

CLEAN-UP SEND ALL BLOOD TO CELL SAVER DISMANTLE TUBING CLEAN UP PUMP FOR ANY BLOOD STAINS PAPER WORK SET UP BACK UP PUMP SET UP BACK UP CELL SAVER