By Mark Ard
By Mark Ard
“Napkin drawing” is a term that describes diagrams that literally look like they were drawn on a napkin, devoid of proper axis labeling and/or not entirely reflective of real observations. They serve to highlight a few key concepts without getting bogged down in the details.
Loops tend to make for good napkin drawings ( see episode 1). Now technically these images have axes, but the key here is that the actual contours are basically freehanded, poorly. Their shape, however, tells a story about what’s going on in the lungs.
Let’s work our way counter-clockwise around a normal lung first. A patient begins at maximal exhalation, the rightward most point on the loop (Residual Volume, if you’re trying to memorize all the different lung volumes). They inhale to their Total Lung Capacity, the far left point. As they switch from inhalation to exhalation, they cross the zero flow line and start exhaling. To start, the patient is in the “effort dependent stage” as their expiratory rate increases to 8L/s. Then the force becomes “effort independent” as their flow rate decreases until they finally poop out. (more…)
Check out today’s Step 1 Qmax Question Challenge.
Know the answer? Post it below! Don’t forget to check back for an update with the correct answer and explanation (we’ll post it in the comments section below).
An 18-year-old college student presents to the student health clinic with a complaint of copious yellow vaginal discharge. She has been sexually active with a new partner for the past month, but she is unsure if her partner is monogamous. A speculum examination reveals petechiae in the upper vagina and malodorous, yellow-green discharge. A potassium hydroxide preparation reveals no organisms, and results of phase contrast wet mount microscopy are shown in the image.
Which of the following is the most appropriate treatment?
A. Treat her and her partner with oral fluconazole and test for other sexually transmitted diseases
B. Treat her and her partner with oral metronidazole and test for other sexually transmitted diseases
C. Treat her with oral fluconazole and test for other sexually transmitted diseases
D. Treat her with oral metronidazole and test for other sexually transmitted diseases
E. Treat her with vaginal fluconazole and test for other sexually transmitted diseases
F. Treat her with vaginal metronidazole and test for other sexually transmitted diseases