The heart is responsible for pumping oxygen-rich blood from the lungs to all of the body’s organs, including itself. Our organs must receive a constant supply of oxygen to function normally, which does not happen when the heart has stopped during a cardiac arrest. Without oxygen, the heart cannot generate the energy to start pumping blood again. As the length of time of cardiac arrest increases, the amount of oxygen debt in the body adds up, making it increasingly more difficult to restart the heart.

When a person remains in cardiac arrest after five minutes of CPR, it is important to provide them with more oxygen to help restart the heart. Our body carries oxygen using a protein called hemoglobin, which is found in red blood cells (RBCs). RBC transfusions are commonly given in hospitals to people with anemia (a condition where the body does not have enough healthy RBCs) to increase the amount of hemoglobin in the body and improve oxygen delivery to the organs.

Previous research carried out by our study team and others have shown that people who have more hemoglobin at the time of cardiac arrest are more likely to survive. It is assumed that this is due to the increased ability to deliver oxygen to the body’s vital organs.

For this study, we plan on giving PRBC transfusions to patients who experience cardiac arrests lasting longer than five minutes to increase the delivery of oxygen. By delivering more oxygen to the body during this critical time, we hope to improve the likelihood of restarting the heart when traditional CPR methods have not been successful.