I'm a pulmonologist who spends most of my clinical time in the ICU. In pulmonology, there are observational pearls I find myself using a lot both in the ICU and on the wards. I ask trainees to slow down and think about respiratory rate. Very often as you're talking to someone, you can notice if there are obvious signs of respiratory distress: if they're not able to speak in full sentences, if they're using accessory muscles, if they're adopting a characteristic position that might suggest that there's an increased load on the respiratory system or obstructive lung disease.
But we oftentimes miss subtle findings. What I encourage my residents and medical students to do at the bedside is to match their breathing to the patient and to simply ask themselves the question, “Do I feel short of breath?” Unless you just ran to an emergency or you walked up a number of flights of stairs, most often if you find that you feel a little bit short of breath, chances are the patient is breathing rapidly. We know that recording respiratory rate in the chart is notoriously inaccurate, but this is simple: Slowing down and just matching your breathing to the patient can oftentimes give you a clue that there's a subtle increased load on the respiratory system. And I use that every day.
We were recently seeing a person on rounds, and we were able to notice that her respiratory rate was in the mid-20s per minute, even though she wasn't clearly using accessory muscles or contracting her abdomen or having other obvious signs of respiratory distress. That led us to do a more focused pulmonary examination, and we discovered that she had a pleural effusion.
The other thing that I'll couple with that is not just observing respiratory rates and even patterns of respiration, but looking for symmetry—or, more importantly, asymmetry—in the chest. This is something you can often see from the foot of the bed. If you notice that one side of the chest is not moving the same as the other, there's almost always a problem on the side that's not moving as well.
For example, if you have someone who's got fever and cough, and one side of their chest isn't moving the same as the other, the likelihood ratio for pneumonia is above 40 (which means that they almost certainly have a pneumonia). I can't think of a more robust likelihood ratio that predicts pathology. In the ICU after an intubation, if someone's left chest isn't moving the same as the right, it almost always means that you have a right main-stem intubation, although it could also mean you have something like a pneumothorax. This is something you can do with observation, but it's also really helpful to just lay your hands on someone's chest. We teach this a lot, putting your hands on someone's back to see if your thumbs turn upward to look for that respiratory symmetry, and that's important. But I would also encourage people to do it in the front. I can't tell you how many times in the last month we've detected pathology in someone's chest because one of their anterior chest walls was not moving the same as the other.