AP BIOLOGY

Detailed explanation-1: -The maximum time period allowed for infusion of a single unit of blood is 4 hours. In emergency situations, the infusion rate is not as well established. Infusion rates greater than 60mL/min are dangerous and infusion rates greater than 100mL/min are associated with cardiac arrest.

Detailed explanation-2: -Physiological consequences of transfusing cold blood Cardiovascular system: Decreased cardiac output, decreased blood pressure, increased systemic vascular resistance, dysrythmias(atrial flutter/fibrillation, bradycardia, asystole), cardiac events (ischaemia, angina, myocardial infarction) [4].

Detailed explanation-3: -Abstract. A well-recognized complication of the transfusion of red blood cells (RBCs) is hyperkalaemia. This occurs in paediatric or adult patients receiving massive transfusion and can lead to cardiac arrest.

Detailed explanation-4: -Initiate infusion of blood components slowly at a rate of 50 mL/hr (if appropriate) but no greater than 2 mL/min (120 mL/hr) for the first 15 minutes (neonate and pediatric rates are weight based mL/kg/hr so may not reach this rate).

Detailed explanation-5: -Citrate toxicity Rapid administration of large quantities of stored blood may cause hypocalcaemia and hypomagnesaemia when citrate binds calcium and magnesium. This can result in myocardial depression or coagulopathy.