June 24, 2009
Bypass Surgery
June 23, 2009
Ascending Aorta Replacement Surgery
An ascending aorta replacement was performed by Dr. Merrick on a 53 year old female with an enlarged aortic valve. A sternotomy was performed and the patient was put on a cardiopulmonary bypass, as seen in the mitral valve replacement. The sternotomy, performed to get access to the heart, can be dangerous- I was told the aorta was accidently cut through during this procedure the other day. The medical team worked quickly together to suture the hole in the aorta, as well as prepare the bypass through the femoral artery in the mid-thigh (where a great deal of blood is pumped through to get oxygenated blood to the lower body), instead of using the ruptured aorta. 
Stenosis is a narrowing in the aorta (as shown above). Instead this woman's case was different, the aortic valve was larger than normal and in need of a replacement. The aorta was cut through (as shown in figure B). The destroyed tissue was removed with scissors, leaving two flaps on each side called pericardial patches (shown in figure D as dotted lines near the bottom of the aorta). These flaps were used to eventually suture the prothetic valve tighter into the aortic orifice. Sutures were laced on the exterior edges of the aortic orifice to pull in the new aortic prosthesis (as shown in figure C and D). A hole is made by burning each side of the prothesis tube to make an entrance for the right and left coronary arteries to enter.
After the heart-lung machine was disconnected and the heart began to beat again on its own, there was an obvious leak of blood from a hole in the aorta from behind. There was no easy way to push the heart out of the cavity and suture the hole, but eventually it was found and fixed. We were lucky not to have had to go back onto bypass because it would have taken at least two more hours. June 17, 2009
Mitral Valve Replacement Surgery
This shows the normal blood flow within the heart. The mitral valve properly allows the movement of blood into the lower chamber of the left ventricle.
The mitral valve insufficiency means the valve is not closing, allowing blood flow back into the atrium. The atrium grows and this can lead to heart failure if left untreated. Mild regurgitation remains asymptomatic while moderate to severe cases cause abnormal rhythm problems and shortness of breath.
Usually acute regurgitations are caused by a rupture in the chordae tendinae, the long cords extending into the left ventricle from the mitral valve, during a heart attack or other trauma. When the chordae tendinae aren't working properly, the blood volume increases in the left ventricle and causes an increase in pressure in the chamber above. This can cause shortness of breath, fluid accumulation in the lungs, or the body's cells die from starvation of oxygen and nutrients due to the lack of oxygenated blood flow.
The most fascinating thing about the mitral valve procedure is the ability to do surgery on a non-working heart by use of a cardiopulmonary bypass. The heart-lung machine replicates the job of the heart (to oxygenate the blood and get it to the rest of the body) so that the heart can stop pumping during the procedure. The heart, a working muscle, is located in a small chamber within the thoracic cavity. Above is a picture of the heart as it lies inside the thoracic cavity- the sternum bone and its attached rib cage with inner lying intercoastal muscles. Below the heart is an underlying muscle tissue called the diaphram that seperates the thoracic cavity from the lower body. The incision for the procedure is made along the dotted lines, shown in the picture above. A median sternotomy incision is performed (the sternum is sawed down the middle with a sternum saw), allowing an ideal view of the beating heart once the retractors are in place.
All the tubes shown in the photo to the left are the tubes that take the place of the beating heart. Cardiopulmonary bypass involves making a small incision in both the superior and inferior vena cava and inserting a special tube connected to the heart-lung machine. Another incision is made in the aorta and connected to the opposite end of the heart-lung machine. The inserted tubes insure that blood leaves the body before reaching the heart and returns back to the body, allowing the surgeon a still and bloodless area to work with. The constant pumping machine, guided by the perfusionist, works as the heart would by taking the de-oxygenated blood to be exchanged for oxygenated blood and then directed to the rest of the body to exchange among the other cells. The de-oxygenated blood is directed to the machine's resovoir, then to the oxygenator, and then through the pump to be pushed back into the body. I found it to be so amazing how the machine (refer to photo below) is capable of doing the heart's job to allow the heart to be worked on for the procedure, especially the ability to exchange carbon dioxide for oxygen. Once the bypass was set up, 32 minutes after the incision, the heart lost its size inside the cavity and shrunk as it came to a complete stop. The screen that once demonstrated the heart's pressure, EKG, and voltage became clear. Then, like magic, the heart's information appeared on the heart-lung machine's screen. The heart sat in its place silently and the patient continued to live- wow! One of the surgeons told me that the one thing that has stuck with him through medical school were the three things that are needed to keep a patient alive: 1) oxygenated blood 2) blood flow throughout the body 3) continued urination which allows filtration of the blood. With help of the heart-lung machine, these three important factors are allowing the patient to stay alive.
The most important part of the procedure is keeping the heart at a mild hypothermic level of 34 degrees Celsius. This cold temperature decreases metabolism and helps protect major organ systems from a lack of blood flow because for every 1 degree Celsius drop of body temperature, the metabolic demands of the body are decreased by 7%. Ice was constantly placed inside the thoracic cavity and when levels rose, the procedure was put on hold until the temperature was confirmed to be at a hypothermic level. The blood that ran through the heart-lung machine was also kept at a low temperature for its return to the body. A third tube is also connected to the heart, but not to the heart-lung machine. This tube flushes the heart with cardioplegia, a potassium chloride solution to stop the heart without damaging it. An increased amount of potassium levels in the blood is a condition called hyperkalemia and is what causes heart failure, which is why it is a third of the ingredients for lethal injections.June 7, 2009
Closer To Reaching My Goals
I think this semester was a success because I didn't have a job or a race to train for and really spent all my energy into completing my Calculus homework and reading every chapter for Organic Chemistry. Plus, there was no way I could fail with nothing to complain about... I have an amazing boyfriend to look up to for working 10 times harder than I do and a perfect place in the city with a parking spot!
Greg and I swimming in Lake Mendocino the day after my last final.
Greg and I biking Orr Springs Rd. during a trip to the Mendocino Coast.April 6, 2009
The Balancing Act

Teana racing with my 2009 Specialized Allez road bike in her first race ever.

Greg racing in his first race of the season.
Miami International Triathlon, March 15th
Greg and I before his race in Miami.
Oceanside 70.3, April 4th
April 5, 2009
The Right Spot At The Right Time
I came into the hospital's Trauma surgery department at 8 am and began doing the normal rounds. I was told there was a new patient who was to have surgery that morning. I became excited- only because I loved surgery, and began reviewing the patient's chart as I walked into the patient's room. When I walked into her room, the nurses were already preparing to relocate her to the OR. I introduced myself to Trinidad. As the nurses were trying to transfer her to the OR bed, Trinidad began asking what was going on. She was scared, crying and had no idea what was happening. The nurses began telling her that she was immediately going into surgery. Trinidad looked at me with tears and fear in her eyes and said, I can't pay for the surgery. At that moment, I just knew why I was put in that spot and I told her not to worry. I told her how I was from United States and before coming to Bolivia, people donated money to be able to help people while I was here. I told her that I could give her $100 to pay for the surgery. Unfortunately, that was all the money I had left and it would not cover the full amount of the surgery. The missing amount was close to $20, which she said she could get from her daughter.
Dressing the wound at the end of the surgery.
January 22, 2009
Hospital Memories
January 20, 2009
Hip Dysplasia
Uncommon in United States, half of Dr. Angulo’s clinical patients are referrals from pediatrics to confirm hip dysplasia in babies under 5 months old. Babies after 3 months old are usually referred to an orthopaedic specialist for confirmation that their hips are growing correctly. Hip dysplasia is when the hip bone shifts up and the humeral head shifts out of the socket. The model shows that the yellow part of the humeral head has shifted out of the socket. It can be genetic or formed due to positional circumstances.
This x-ray shows the left angle at 3o cm and the right angle at 37 cm. A diagnosis for severe hip displaysia.
When the hip is diagnosed early, treatment can correct the deformation. Treatment includes an apparatus (cost is about $11) that holds the femoral bone externally rotated with the legs spread. The apparatus (shown on left) is worn for a minimum of 3 months, 24 hours a day. After the third day, the apparatus can be taken off for 15 minutes to give the baby a shower but must be put on immediately. If the dysplasia is minor, exercises are prescribed. The exercises include moving each hip joint in 10 circles 3 times separately with each side every day until the dysplasia is gone.
Today a 5 month old baby came in and I measured 30 cm on the left hip and 35 cm on the right. In November, the patient was measured at 27 and 27 cm. Within two months the baby had grown hip dysplasia. An apparatus was given to correct the deformity. Another 7 month old came in who had a 38 cm measurement on the right side. Because the baby had gone so long without treatment, the acetabelum had grown a roof (it takes about 11 months to form) and would not allow the humeral head to be pushed back into the socket with treatment alone. In this case, surgery was the only treatment so that the acetabelum could be chipped away at to allow room for movement in the socket.
For most patients living in Bolivia’s indigenous communities, no access to pediatrics, or the Bolivian pediatric doesn’t properly diagnose nor refer thepatient to an orthopaedic specialist, the patient can go undiagnosed and untreated for many years. Going undiagnosed between the ages of 14-16 years old is the most dangerous. Bolivian doctors end up seeing patients who are well into their adult years for hip dysplasia. This is when surgery is the only option.
Hip dysplasia surgery for adults is dangerous and very invasive. If the cartilage in the hip’s acetebelum is still intact, a procedure invented by the Swiss is performed. Most likely, the hip is arthritic. That was probably the primary reason the patient even went to the doctor in the first place, and then happened to get diagnosed with hip dysplasia. When the hip is arthritic, arthroplasty is recommended to replace the arthritic femoral head and acetabelum.
Arthroplasty is very common in United States. 168,000 Americans undergo hip replacement yearly. I have done research and have viewed many hip replacement surgeries by the popular Orthopaedic surgeons (Dr. Bozic, Ries, Jergesen, Vail) at UCSF Medical Center in San Francisco, California. Patients are always pleased and the outcomes are very beneficial for the patient to continue living a normal and active life.
Hip replacement surgery involves making a large lateral incision at the hip, dislocating the hip joint, the femoral head is cut off and then the acetabelum is reamed. A plastic liner is placed in the acetabelum and a metal femoral prothesis is cemented into the hollow hole made in the femoral shaft. Finally a metal ball is attached to the femoral stem and then hip is placed back into the socket.
Last week, my uncle and aunt invited me to have dinner with them at Dr. Cruz’s house. Dr. Cruz and his family are good friends with my mom as well. I was told that Dr. Cruz was as famous in Bolivia as the other Trauma and Orthopaedic surgeon Dr. Zalles from Hospital Juan VVIII, where I was working. He greeted me with a huge hug and immediately started asking me questions. He had to leave for an emergency call but when he came back we talked about, well surgery of course!! He was one of the smartest and friendliest older man that I’d met, which made our conversation so easy.
When he started sharing his new invention for a hip replacement, our conversation just flowed because that was a topic I knew all about. I told him how I worked at The Biomechanical Testing Facility in San Francisco General Hospital. Everything just clicked and we both started scheming how I could help him bring his invention to United States. With a huge smile on his face, he invited me to his office for an interview. That smile plastered on his face the rest of the night was enough motivation for me to go all out with this project.
I went to Dr. Cruz’s office as the first part of the project. He spent an hour explaining his procedure with me. It was something I had pondered about myself so I was very interested. His procedure follows the regular steps for a hip replacement (refer above) up until the plastic liner is placed in the acetabelum. Before the plastic is placed inside, he carves a very special angled triangle into the bone superior to the acetabelum with a special drill saw. He then uses the femoral head bone that was cut off and shapes it to fit like a puzzle into the angled triangle. He either makes the triangle too small or the femoral head piece too big to purposely make a tight fit in order to initiate the like with like rule. Sometimes if the fit is tight enough, he skips using a screw to keep it stabilized. The purpose of this procedure is to make a perfect fitting superior surface for the plastic liner. His theory is that the plastic liner, which can be cemented or screwed into the acetabelum, can move and therefore cause another displacement. Some older patients that grow arthritic hip bones no longer support the screw holding the plastic liner in place and allow the liner to shift, which requires another surgery. Dr. Cruz’s invention has proven to avoid this for hip replacement patients.
Dr. Cruz’s procedure is currently being used by himself and other local surgeons in Bolivia and is titled, “Encastrado de Cruz” (Encased by Cruz). There is another doctor in New Zealand who had invented a procedure similar to his and they are currently competing for the title. Dr. Cruz plans on attending the World Congress Conference in a few months in New Zealand to try to beat his competitor. My plan is to do a research project in San Francisco, demonstrate that the procedure is worthy compared to the original one, publish the article in a medical journal and have Dr. Cruz come work with the surgeons in San Francisco. Seeing his smile again is worth all the work.To view more photos of the procedure, click here... Dr. Cruz
January 18, 2009
Hip Fracture Repair
As I was holding the knee, he said, "alto". Alto in spanish is not a command, instead it means either stop or high (as in blood pressure). With the mask covering the doctor's mouth, it was already hard to hear his commands. I didn't know if he was talking to me or the other doctor until Dr. Lopez grabbed my hands and lifted the leg up with me. Then Dr. Chavez shook his head and said, "tonta". Tonta means stupid in spanish. 



