Wednesday, October 1, 2014

AP Bio Observes Open Heart Surgery

Yesterday, the Advanced Placement Biology class went on the tenth annual field trip to the Inova Fairfax Heart and Vascular Institute to observe open heart surgery of a patient who was having a Coronary Artery Bypass Graft (CABG) (quadruple). The first thing the students heard was an introductory briefing on the patient’s status by a registered nurse. She explained the kind of symptoms the patient experienced that brought them to the hospital. She then talked about the patient’s genetic history for heart disease and any risk factors they had with a particular focus on things that people can control like smoking, alcohol use and diet. The nurse went on to talk about the byapss the patient was about to undergo. 

Before the students entered the dome, they took a quiz about general heart health. Once in the dome, the nurse talked extensively to the students about what was going on below. She talked about each person in the room and their role. She also shared the kind of education and training a person needs to undergo to do that job. In the room were the cardiothoracic surgeon, the scrub nurse, the perfusionist, the certified nurse anesthetist, the registered surgical nurse, and circulating nurses and anesthesiologist.  

While the procedure progressed, the nurse explained every step from the location and removal of the saphenous vein in the leg using a narrow scope to the opening and preparation of the chest cavity. The students learned about the removal of the vein and the tests it must undergo to ensure the integrity of it as well as the redirecting of blood flow that occurs as a result of the removal. While that was going on, the surgeon prepared the heart by opening the ribs, entering the pericardium and stitching catheters in place to redirect blood flow to the heart/lung machine which circulated the patient's blood and oxygen while the bypass took place. 

One of the most amazing moments occurred when the doctors stopped the heart using a high potassium solution. The Holton students have learned about osmosis and maintaining an isotonic state as well as the importance of ion exchanges across cell membranes. Both concepts proved useful during the observation. While the heart was stopped, the surgeon took sections of saphenous vein and created new pathways for blood flow that successfully fed the heart muscle valuable nutrients and oxygen.


The girls were highly engaged yesterday, asking a lot of great questions and making connections between concepts learned in class and the applications to open heart surgery.