Final answer:
Option A). The nurse recognizes increased blood pressure as the physiologic response to acute pain, as it is directly related to the body's fight-or-flight mechanism.
Step-by-step explanation:
An elevated blood pressure is the symptom that a nurse can identify as a physiological reaction to acute pain. The body goes through a number of physiological reactions when someone is in acute pain, one of which being the sympathetic nervous system being activated. Numerous effects, including elevated blood pressure, heart rate, and breathing rate, may result from this. The body's fight-or-flight response includes many reactions, preparing the body to either confront or flee from a threat. A common response to acute pain is restlessness, which is more of a behavioral symptom than a true physiological response. Restlessness is not as straightforward a metric as blood pressure, which can be measured and observed objectively, even if it can be linked to physiological changes. Blood pressure can also rise as a result of other things including elevated norepinephrine and adrenaline levels, lowered baroreceptor firing rates, and other drugs like caffeine and nicotine.