A 66-year-old female who is usually meticulous about her appearance and dress arrives today for her 23rd day of radiation therapy and appears disheveled and emotionally labile, and her responses to the usual questions are a little inappropriate. Her heart rate is 124 bpm, her respirations are 32 breaths/minute, and her skin is cold and clammy. These findings would suggest that the nurse should further assess the client for which of the following conditions?