|
Method | Subjects | Able pain measure | Consistent across studies | Limitations |
|
Electroencephalogram (EEG) | Neonates, infants, CPPs, ICU patients | Yes | Moderate | Influenced by opioids, not consistently found in neonates |
|
Cardiovascular measures | Heart rate | Neonates, infants, TBI patients, ICU/OR patients, CPPs, people with SID, healthy adults | Doubtful | No | Variable results among brain injured patients, reduced reaction in CPPs, no reaction in SID |
Heart rate variability | Neonates, infants, ICU/OR patients, healthy adults | Yes | Moderate | Inconsistent among infants in the first year of life |
Body temperature | Neonates, infants, healthy adults | Yes | Moderate | Inconsistent among healthy adults |
Blood pressure | Neonates, infants, TBI patients, OR patients, healthy adults | Doubtful | No | Blood pressure responded inconsistently to pain |
|
Respiratory measures | Respiratory rate | Neonates, infants, TBI patients, people with SID, healthy adults | Yes | Yes | Respiratory ‘irregularities’ were not related to acute pain in persons with SID |
Respiratory analysis | Neonates, infants, TBI patients | Yes | Yes | Oxygen saturation was not favored for pain in neonates |
|
Muscular measures | Muscle tension | Infants, ICU/OR patients, healthy adults | Yes | Yes | In healthy adults muscle tension response was only found with intense and prolonged pain |
Electromyogram | CPPs, healthy adults | Yes | Yes | Few studies |
|
Electrodermal activity | TBI patients, OR patients, healthy adults | Doubtful | No | Only consistently found in healthy adults |
|
Pupillometry | Infants, OR patients, CPPs, healthy adults | Yes | Yes | Few studies |
|
Brain scan | MRI | CPPs, healthy adults | Yes | Yes | Different studies focused on different areas |
NIRS | Neonates, infants | No | Yes | Presence of pain on a cortical level was not found |
CBFV | Infants, CPPs, OR patients, people with SID | Yes | Yes | Few studies |
SPECT | Infants, CPPs | Yes | No | Activity varied greatly across studies |
|
Hormonal analysis | Neonates, CPPs | Yes | Yes | Few studies |
|
Genetics | CPPs, healthy adults | Yes | Yes | Not yet validated in large human cohorts |
|
Automatic facial recognition | CPPs | Doubtful | Yes | Influenced by gender, age, ethnicity, movement, and lighting |
|