New pain assessment parameter, called the Variation Coefficient of Pupillary Diameter (VCPD) described. This parameter allows evaluating the pain of patients during uterine contractions in obstetrical labor, and postoperatively in recovery room.

This parameter also allows evaluating the level of pain in Intensive Care Unit (ICU), in intubated or tracheotomized patients moderately sedated (Riker score 3 or 4).

This study propose to recalculate the Variation Coefficient of Pupillary Diameter (VCPD) from pupil recordings performed in the Intensive Care Unit (ICU) in 2015-2016 and kept in the patients' records. From there, the Variation Coefficient of Pupillary Diameter (VCPD) will compare to the Behavioral Pain Scale (BPS), considered the gold standard pain assessment

Inclusion Criteria:

• hospitalized in the surgical Intensive Care Unit (ICU) of the University Hospital of Saint-Etienne between September 2015 and August 2016 for medical-surgical pathologies
• requiring orotracheal intubation or tracheostomy
• and presenting a Riker sedation score of 3 or 4.

Exclusion Criteria:

• cerebral palsy
• curarization
• paraplegia or tetraplegia
• intensive care neuromyopathy
• ocular pathology
• history of severe dysautonomic disease that could influence the evaluation of the Behavioral Pain Scale (BPS) or Variation Coefficient of Pupillary Diameter (VCPD) score
• receiving antiarrhythmic treatment that could make the interpretation of the results difficult
• on metoclopramide, droperidol, clonidine, or dexmedetomidine, which are known to alter the pupil dilation reflex.

Patients hospitalized in the surgical Intensive Care Unit (ICU) of the University Hospital of Saint-Etienne between September 2015 and August 2016 for medical-surgical pathologies, requiring orotracheal intubation or tracheostomy, and presenting on the day of recording a Riker sedation score of 3 or 4 will be included.