This was a *CRAZY* busy week. I must have done 900 thoracenteses this week, so I had some questions about pleural effusions and their effect on dyspnea based on things I observed. Here are my take aways. #MedTwitter #MedEd #PulmCrit #FellowLife
1/ I felt like a hero - swooped in, did a thoracentesis, drained 1.5L... and her breathing didn't get better. I was like... 😕wtf. It turns out size of pleural effusion correlates poorly with dyspnea. This holds true for reduction in symptoms after thoracentesis.
2/ Did another thora, and his SpO2 was WORSE after. 😖I'm like... WHAT'S WRONG WITH ME? Things can actually worsen immediately after thoracentesis (even without mucking it up) for a few hours. Also, gas exchange issues DON'T correlate with the symptom of dyspnea!
3/ Dyspnea and hypoxia with pleural effusions aren't just from atelectasis. Effusions increase pleural pressure, which in turn, flattens (and reminder: SHORTENS) the diaphragm, decreasing maximum diaphragmatic tension. Sort of like hyperexpansion in emphysema! 
4/ Flattened diaphragms require more neural activation in order to generate the same degree of tension (if at all possible). Now you can see why patients "tire out," and why positive pressure ventilation (one of many reasons) helps to decrease their work!
5/ I reminded myself of that fact when I saw it in real life during my #POCUS, and saw a bright white line, that I knew must've been the diaphragm, but it looked too flat! I drained some fluid, and looked again. Low and behold, the diaphragm retook its normal shape.
6/ Thanks for coming to my Saturday morning #MedEd #Tweetorial! Source/further reading for my other #pleural nerds out there: bit.ly/PLEFFPhysio
Don’t worry. I didn’t violate my work hours! Not did I *actually* do 900. Just felt like it!
