In simple words: The doctor sets up and runs a machine that pumps and adds oxygen to a patient's blood outside of their body. This is done for each hour of use and might include checking the patient's blood pressure and heart rhythm. This machine helps during heart surgeries.

The provider assembles and operates a mechanical pump-oxygenator or heat exchanger for the circulation and oxygenation of blood outside the body. This service is for each hour and may or may not include monitoring of the patient’s blood pressure and performing an ECG, or electrocardiogram.Preparation and operation of a pump oxygenator or heat exchanger is essential for cardiac surgeries. The provider prepares, tests, and manages the system, which consists of interconnected devices that replace the heart and lungs. The system removes oxygen-deprived blood from the patient and replaces it with oxygen-rich blood. Three main components are the pump (artificial heart) which maintains and controls blood flow; the oxygenator (artificial lungs) which transfers oxygen to infused blood and removes carbon dioxide; and a heat exchanger which warms or cools the perfused blood. The provider assembles the oxygenator under sterile conditions, connecting various mechanisms following established protocols and checklist verification of proper circuit assembly and function. This checklist includes sterility of components; proper assembly and function of the pump; adequacy of electrical connections and oxygenator gas supply; arrangement and reliability of lines; composition of priming solution; testing and activation of alarms; functionality of the water supply system; verification of automated anticoagulation; and availability of backup supplies and equipment. During the procedure, the provider operates and manages the system and may monitor the patient’s blood pressures, temperatures, and electrocardiogram.

Example 1: During a complex coronary artery bypass graft (CABG) surgery, the cardiopulmonary bypass (CPB) machine (pump-oxygenator) is used to temporarily take over the functions of the heart and lungs, allowing the surgeon to operate on the heart. The code 99190 would be reported for each hour the perfusionist operates the CPB machine., A patient undergoes a valve repair procedure.The surgeon uses CPB, and the perfusionist manages the pump-oxygenator for the duration of the procedure.Code 99190 is used for each hour of CPB operation., In a pediatric heart surgery, a smaller, specialized pump-oxygenator is used. The perfusionist assembles and operates this device, and the time spent is tracked and billed using code 99190.

* Detailed operative report specifying the duration of CPB.* Anesthesia record indicating the start and end times of CPB.* Perfusionist's report documenting the assembly, operation, and any complications encountered with the pump-oxygenator.* Verification of the proper functioning of the CPB machine.

** This code is typically reported by the perfusionist. The exact time spent on assembly and operation should be carefully documented.The use of this code should adhere to all applicable payer guidelines and policies.