Blood transfusion and CPB Noura K. AL Zeer Cardiac perfusionist Prince Salman Heart Center King Fahad Medical City
Objectives :
•Introduction •Blood products
•Risk and side effect of blood transfusion in cardiac surgery •Acceptable hematocrit levels in CPB patients
•Reasons for low HB. • What is the solution?
•When do we consider adding packed red blood cell? •If there is no choice ..and we have to transfuse blood..we have to check the following ..
Introduction • Blood transfusion is very important for our patient survival during open heart surgery. Specially for anemic patient and high risk patient ( who may have bleeding during the surgery ). • That doesn’t mean there is no side effect or complication for blood transfusion .
Blood products • When we talk about blood we talk about three important parts: • Red blood cell . • Platelets . • Plasma .
Risk and side effect of blood transfusion in cardiac surgery • • • • •
Allergy. Pulmonary complication. Incidence of renal insufficiency. Transmission of infectious diseases . Early and late febrile, cutaneous or hemolytic immune reaction. • Bleeding. • Mortality.
As a perfusionist most of the time we do blood gas analysis during the surgery every 30 minutes to check the HB ,PH , electrolytes, CO2 and O2 saturation . when we see the low HB, We start look again to the case ..
Acceptable hematocrit levels in CPB patients (Male: 42 - 54%,Female: 38 - 46%) These numbers before the cardiac surgery . The changes in hematocrit during the intraoperative period were studied in 50 patients .. Mean preoperative hematocrit was 44% and dropped to 30.8% during the pump run. Target hematocrit 22% to 24% during CPB . The records of 348 consecutive patients age 70 years or more, who had heart surgery Intraoperative strokes were defined as those patients who had a new neurologic deficit after CPB. The relationship of stroke to hemoglobin level was investigated in 347 patients , the data does not show a cause, but an association between low hemoglobin and stroke in patients 70 years and older. That mean the target hematocrit for old patient during CPB will be higher .
Reasons for low HB • Hemodilution because of the Extra fluids (prime , pre bypass fluids). • Temperature effect. • Blood diseases (anemic patient ,systemic lupus erythematosus, sickle cell anemia). • There is blood loss.
Temperature effect • During CPB we start with normothermia usually, then we start cooling the patient when the x-clamp on, after that we start rewarm the patient. • Vascular tone effected by temperature changes so when the temperature increase it cause vasodilatation and when its decrease it cause vasoconstriction.
• Some times it will effect the volume in our pump and in the patient. • When the volume decrease in the reservoir during rewarming we avoid adding fluids to prevent hemodilution that could happen at the end of the case and effect the HB . • We try to come off with this volume and avoid adding blood , and maintain good hemoglobin .
Blood loss during CPB Hemolysis cause blood loss during CPB What is hemolysis? Is the breakage of the red blood cell’s (RBC’s) membrane, causing the release of the hemoglobin and other internal components into the surrounding fluid. Causes : Very tight Occlusion. High flow in the Suction and vent.
What is the solution ? Its not just add blood to the circuit and transfuse it to the patient and have good number !!
There is important steps!
•Communicate with the surgeon and anesthesia . •Think about other solution in your pump can help you such as hemoconcentrate blood by removing extra fluids. •Use the cell saver . •Use autologous blood that collected pre operative. •Try to protect patient from adding packed red blood cells.
Autologous blood Autologous blood transfusions are advantageous because they introduce reduce the risks for immune reactions and infections. Autologous blood transfusion is a common, safe and well established practice. It avoids many, if not all the risks and has the benefit of transfusing red cells that rapidly become functional. Furthermore, it relieves the constant pressure on the already limited supply of banked blood.
• What is an autologous blood transfusion? The blood which a patient donates prior to their scheduled elective surgery is stored and saved for their use. When the blood is given back to the patient, it is called an autologous blood transfusion.
• Who decides if you should be an autologous blood donor prior to your surgery? • If there is a possibility that you will need a blood transfusion during your surgery. • Your surgeon may recommend an autologous blood donation. • The type of surgery determines the need for autologous donation . • The health of the patient determines their ability to donate.
When do we consider adding packed red blood cell? When all the solutions that we try don't work to make the patient in better situation.
If there is no choice ..and we have to transfuse blood..we have to check the following: • • • • •
The age of blood. The expire date. The blood group. The information of patient. Inform the anesthesia .
• The structure of red blood cells changes over time . • The cells become less flexible and don't maneuver as easily inside blood vessels, which could increase the chances of clots. • The cells become less efficient in transporting oxygen or carrying out other functions. • When red-blood cells break open, hemoglobin inside the cell scavenge nitric oxide. • Once the hemoglobin snatches up the nitric oxide the nitric oxide is no longer able to regulate cardiovascular function. Blood flow to critical organs could be reduced, the blood may clot more readily and inflammation could occur, which may result in dangerous events for some patients.
Clinically, the age of blood has been associated with: • Multiple organ failure. • Postoperative pneumonia. • Wound infection. • Cytokines and other inflammatory mediators have been shown to accumulate during storage of blood products.
• According to current U.S. FDA guidelines, donated blood can be safely stored for up to 42 days , But results from some recent studies suggest that heart patients transfused with blood preserved more than two weeks after donation appear at higher risk for bad outcomes than those who get donated blood that is less than two weeks old. • The New England Journal of Medicine published an influential study looking at the mortality rate of 6,002 heart surgery patients , the mortality rate of 2,872 heart-surgery patients 48% who had received blood stored for 14 days or less, compared to that of 3,130 patients 52% who got blood stored for more than 14 days.
The blood groups
The Rhesus Factor There is one more important antigen on the surface of red blood cells. It is called the Rhesus-D antigen. This antigen mechanism is again inherited from your mother or father. This adds another qualifier to a blood type under the ABO blood group classification system. A person with any of the four blood types may be Rhesus D positive (Rh+) or Rhesus D negative (Rh-). So that increases number of blood types to eight (A Rh+, A Rh-, B Rh+, B Rh-, AB Rh+, AB Rh-, O Rh+, O Rh-).
The information of the patient such as :
• The full name of patient. • The MR number. • Patient blood group.
In Conclusion , Patients’ blood management is “timely application of evidence-based medical and surgical concept designed to maintain hemoglobin concentration, optimize homeostasis and minimize blood loss in an effort to improve patient outcome.
Create Task Force for blood management include(cardiologist , surgeons , anesthesiologists ,blood bank personnel, perfusionist and nurses) to make program that help to limit the blood transfusion ,decrease postoperative bleeding and improve the outcomes.
Thank you