From our anonymous insider…
We started our exploration of the respiratory system in anatomy by using bone saws to remove the chest plate, thus opening the thoracic cavity. Half an hour after we started sawing, I was holding a human lung: heavy, fluffy, yet slippery to the touch. Unlike textbook depictions, they are asymmetric. The three-lobed right lung is larger while the the left lung has only two lobes. The aortic arch and descending aorta carve out a large groove in the posterior left lung. Comparing cadavers, it wasn’t hard to spot a smoker’s lung: copious amounts of black specs on the exterior plus one cadaver had burst alveoli. If you see a doctor smoking you’ll know that he or she really loves cigarettes.
My group finished early and snuck a peek by opening up the pericardium (membrane that covers the heart). The heart is surprisingly small, about the size of a clenched fist. We don’t have any information about how our cadaver donor died (aged 97), but we noticed a dark red spot on the left side of the heart, surrounded by firm white tissue. Our instructor explained that this indicated a left ventricular myocardial infarction (“heart attack”) and said that, if the patient had survived, the affected area would have remodeled into tough scar tissue. One small spec on a small organ is the difference between life and death.
We learned in lecture that the breathing system is like two springs: (1) the lung, which wants to collapse, and (2) the chest wall, which wants to expand. The lungs are stretchy, with a third of the elasticity from the tissue itself, and two-thirds from surface tension of the copious fluid coating the airways. They’re constantly being pulled open by the pleural membranes, connected to the chest wall. We disrupted the balance when we cut through a rib, which sprung outward, no longer constrained by the recoiling lung.
Our patient for the week had been morbidly obese, which led to sleep apnea, which led to pulmonary hypertension. Excess weight on her chest and neck obstructed airways and elevated thoracic pressure. Prescribed a CPAP oxygen machine, her compliance was haphazard, which is typical with this immensely uncomfortable contraption, despite the patient’s ability to choose her favorite mask color. Sleep apnea, with its intermittent decreased blood oxygen saturation, can lead to increased pulmonary artery pressure. This had caused her right heart to work harder pumping deoxygenated blood into her pulmonary arteries. Over the years this made it impossible for her to exercise. She felt continuously exhausted, unable to walk up a few stairs or stay awake during any prolonged meeting. She quickly used up all her vacation and sick days and had to quit her job, moving in with her sister 200 miles away. Her new doctor recommended she speak with a pulmonary hypertension (PH) specialist, a relatively new field spurred on by the rise of obesity and sleep apnea. The PH Doc described his reaction after the first visit: “I did not expect her to live for more than two-years. I thought her right heart would fail.” He continued by explaining the unfortunate truth for PH. “Pulmonary hypertension was an inescapable death sentence until the late 1990s. There is no surgical intervention and no drugs. Studies showed that over 50 percent of patients with severe PH die within two and a half years.” In the late 90s, pharmaceutical companies developed new classes of drugs to treat left heart failure and hypertension. Some of these turned out to temporarily reduce pulmonary hypertension, giving patients a brief window in which to lose weight. Our patient was able to complete an aggressive exercise and rehabilitation routine. Five years post-diagnosis, she is no longer morbidly obese, exercises daily, and has gone back to work part-time.
The PH Doc ended by reminding us not to be blinded by obesity in a patient: “Doctors too often blame all symptoms on obesity, even if there are other pathologies that can be treated.” For color he told us about the challenge of not offending a patient while saying “we need to send you to the zoo where there is a larger-sized scanner…”
Sunday evening a few students were invited to my favorite professor’s cabin. She is a never-married woman in her late 60s who has dedicated her life to the craft of trauma surgery. She entered medicine expecting to go into family practice. While a third year student, she requested to be sent for her family medicine rotation to a rural area. She drove into the mountains to a small mining town of 10,000 with two family physicians. Although regretting her decision at first, it was here that she learned to love emergency medicine. Sitting around the bonfire, she shared vivid memories of driving the ambulance up moonlit dirt roads to a mine and going down the shaft to retrieve injured miners.
What has changed in trauma surgery? “Well the cases have changed,” she answered. “I started out treating young males in high-velocity, multi-trauma injury cases: car accidents, gunshot wounds, stabbings. Now it is mostly low-velocity cases: an elderly patient who has fallen. The family feels terrible for not having been there when the trauma occurred. The family flies cross-country to say ‘Do everything you can to keep Grandpa alive,’ not understanding what this requires doctors to do. Too often they ignore palliative care.” She’d learned about hospital funding priorities: “It is easy to find donors for a state-of-the-art pediatrics wing; there is no money to remodel a decrepit geriatrics ward.” Her bonfire advice to us: (1) find a field where you will get more interested in it as you go on; (2) you can be happy in more than one residency field (i.e., don’t cry if you don’t get your first choice).
Statistics for the week… Study: 8 hours. Sleep: 6 hours/night; Fun: 2 outings. Example fun: Camping with Jane and Sunday BBQ at trauma surgeon’s cabin.
The Whole Book: http://tinyurl.com/MedicalSchool2020