Observational Study of an Automatic Detection of Patients at Risk of Chronic Postoperative Pain (Alerte Douleur)

Study Overview
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Brief Summary
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Following surgery, some but not all patients develop persistent (or chronic) postoperative pain CPSP. Several risk factors for this persistent pain have been confirmed in previous studies, but neither surgeons nor anesthesiologists have or take the time to systematically screen patients for this risk. However, hospital information systems often contain the data already, entered during preoperative consultations (e.g. chronic opioid medication) or obtained during the postoperative period (e.g. pain scores). Here the investigators test an automatic detection algorithm which alerts the analgesia team when a patient at risk of CPSP is or has been operated.

Detailed Description
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The primary aim of the study is to confirm that the sensitivity of the automatic alert is at least 80%, i.e. that 80% of patients with the primary outcome had an automatic alert. The secondary aim of the study is to develop an algorithm (combination of risk factors) with which the specificity of the alert can be improved.

Official Title
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Étude Observationnelle Prospective d'Une Alerte Douleur informatisée Automatique Par Les Applications Informatiques hospitalières Des HUG Pour prédire l'Apparition de Douleurs Chroniques Post opératoires

Conditions
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Pain, Postoperative

Intervention / Treatment
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* Diagnostic Test: automatic risk detection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18 years of age elective surgery perioperative use of the hospital information system surgery of the following types: endoprosthesis of the knee or shoulder, amputation other than toe or finger, spinal surgery, cardio-thoracic thoracotomy, laparotomy, inguinal hernia repair, breast surgery Exclusion Criteria: inability to read and understand the consent form or the questionnaires emergency surgery having already participated in the study for another surgery

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Diagnostic Test: automatic risk detection|automatic alert of the risk for CPSP, triggered by one of the following entries in the hospital information system: psychological risk factors (depression, anxiety, PTSD, catastrophizing, high pain anticipation), chronic use of benzodiazepines or opioids, intense postoperative pain or need of large opioid doses in the recovery room|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| CPSP at 6 months | mean pain intensity in the brief pain inventory of at least 3/10 | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| CPSP at 12 months | mean pain intensity in the brief pain inventory of at least 3/10 | 12 months | 
| clinically significant pain at 6/12 months | either a pain intensity of >=3 at rest or >=5 on movement or use of analgesics | 6/12 months | 
| neuropathic pain at 6/12 months | mean pain intensity in the brief pain inventory of at least 3/10 AND a DN4 score of at least 4 | 6/12 months | 
| acute postoperative pain | mean pain score and highest pain score in the first 24h postoperative on a 0-10 verbal numeric rating scale | 24h postoperative | 
| pain-related functional deficit at 6/12 months | pain interference scales of the brief pain inventory, number of days not working | 6/12 months | 
| persistent opioid use | patient reported use of tramadol (yes/no) or use of strong opioids (yes/no) | 6/12 months |