In which situation is it critical for a nurse to contact the physician regarding a patient's condition?

Contacting the physician is particularly critical when a patient's pulse is unusually low because this can be indicative of serious underlying health issues. A low pulse, medically referred to as bradycardia, can be a sign of several conditions such as heart block, medication effects, or other cardiac abnormalities that may require immediate intervention. Monitoring vital signs like pulse is crucial for assessing a patient's cardiovascular stability, and any significant deviations from normal ranges warrant prompt medical evaluation to prevent potential complications.

While anxiety, normal temperature, and fluctuating weight might be relevant concerns, they typically do not pose the same immediate risk to the patient's safety or require urgent medical intervention as an abnormal pulse would.