The Post-ICU Pain Study

Patients are defined as having pain if they answer "yes" to question number 1 in the Brief Pain Inventory - Short Form

Additional components of the Brief Pain Invenstory Short Form

Definition of new-onset persistent pain: Individuals presenting with pain according to Brief Pain Inventory Short Form at 90 AND 180 days follow-up AND not suffering from persistent pain/using pain medication regularly before ICU admission, as reported by the individual.

The EQ-5D-5L comprises 5 components (mobility, self-care, usual activity, pain/discomfort, and anxiety/depression) which can be rated at 5 levels. Furthermore, a Visual Analog Scale (VAS) documents self-rated health

The respondent is asked to rate the overall quality of sleep over a 7-day recall period on a VAS. Respondents are instructed to consider the following components before answering the questionnaire: hours of sleep, night wakings, how easily they fall asleep, how often they wake earlier then needed, and how refreshed they feel when waking. Sleep quality is scored as follows: 0 = terrible, 1-3 = poor, 4-6 = fair, 7-9 = good, and 10 = excellent

It comprises seven questions regarding anxiety and seven questions regarding depressive symptoms. Anxiety and depression are scored separately with recommended cut-off values of 8-10 for possible presence of a mood disorder and >11 for probable presence of a mood disorder

Only patients answering "yes" to the Brief Pain Inventory Short Form, question number 1, will be asked to fill out the S-LANSS. The tool was created as a clinical tool to identify pain primarily of neuropathic origin, allowing for the differentiation between neuropathic pain and nociceptive pain. It contains 7 items assessing pain quality, sensory changes and specific symptoms commonly associated with neuropathic pain. A score above 12 suggests neuropathic pain

QST SUBSTUDY: This test includes a series of tasks designed to examine physical performance. The SPPB requires limited space and takes about 10 minutes to complete. It contains 3 domains (3 m gait speed, 5 times chair stands, and 3 progressive standing balance tasks). Each component is scored separately, and a total score is calculated. The maximum score is 12 indicating little to no mobility impairment

QST SUBSTUDY: The questionnaire assesses pain intensity (three questions), pain course patterns, the location of pain and presence of radiating pain (via a body chart), and sensory descriptors of pain (seven questions). Scores of 0-12 indicate neuropathic pain component is unlikely, scores of 12-18 indicates results are ambiguous, however a neuropathic component can pe present, and lastly scores of 19-38 indicates neuropathic pain component is likely

QST SUBSTUDY:

• simple reaction time (seconds)

QST SUBSTUDY:

• Thermal thresholds: Thresholds are determined by increasing the thermode temperature from baseline 32°C (ramp rate + 1.0 °C/s) until the subject activates the 'stop' button. WDT is defined as the point at which the patient first perceives a sensation of warmth. HPT is defined as the point at which the thermal sensation first turns into pain. The cut-off temperature is 50°C, avoiding the risk of thermal skin injuries

QST SUBSTUDY:

• Pinprick thresholds and temporal summation (mN)

QST SUBSTUDY:

• Offset analgesia (numeric rating scale; 0-100).

QST SUBSTUDY:

• Conditioned pain modulation (seconds): includes the cold pressor test (CPT; conditioning stimulus) and pressure algometry (test stimulus).