How can Pain be Assessed? > Objective Assessment
Physiological Responses to Pain
Physiological responses to pain are mainly aspects of the body's integrated defence response including Fight or Flight. The two main systems are (1) the Sympatho-Adrenal (SA) system and (2) the Hypothalamic-Pituitary-Adrenal (HPA) system.
Physiological signs of pain may include:
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dilatation of the pupils and/or wide opening of the eyelids
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changes in blood pressure and heart rate
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increased respiration rate and/or depth
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changes in skin and body temperature
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increased muscle tone
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increased defaecation and urination (Kania et al 1997)
 
