Pulmonary Edema?

I am a new grad in the ICU. This may be a silly question but can someone tell me what pulmonary edema sounds like? When I do my assessment on my patients and I listen to his or her lung sounds many times the bases sound diminshed or I can hear bowel sounds (because they are laying)...does it sound gurgly? loud? Is there anything I can key into?
I know to look at O2 sats, distress, anxiety, shortness of breath...but what if the patient is not experiencing any of these symptoms or they cannot communicate this to me.
I would appreciate any feed back, correction, guidance...