Effects of Perioperative Systemic Ketamine on Development of Long-term Neuropathic Pain After Thoracotomy

Study Overview
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Brief Summary
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Lung surgery under thoracotomy is known to induce long-term pain which can be considered as neuropathic in many patients concerned [1,2]. The suspected origin of neuropathy is a direct traumatism of intercostal nerve(s) [3]. Among the possible preventive treatments that can be administered during the initial aggression, ketamine [4,5] appears as the easiest to use, as it is already commonly administered intra and postoperatively for improvement of analgesia [6].

Detailed Description
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Lung surgery under thoracotomy is known to induce long-term pain which can be considered as neuropathic in many patients concerned [1,2]. The suspected origin of neuropathy is a direct traumatism of intercostal nerve(s) [3]. Among the possible preventive treatments that can be administered during the initial aggression, ketamine [4,5] appears as the easiest to use, as it is already commonly administered intra and postoperatively for improvement of analgesia [6]. This study compares two groups of patients undergoing thoracotomy for partial pneumonectomy, one receiving intravenous ketamine since the beginning of procedure and then during 48 hours, the other receiving inactive normal saline (placebo). The study is prospective, randomized, and double-blinded. The primary endpoint is to reduce chronic pain (on visual analogue scale) at the 4th month after surgery with ketamine. The objective is to obtain a mean value under 20/100 in the ketamine group, considering that the expected mean value for the control group is 38/100 (based on personal observations). The secondary endpoints are lower scores of neuropathic pain in the ketamine group, assessed by the NPSI questionnaire [7]. The impact of treatment on quality of life, assessed by a questionnaire (SF-36), is also studied. The data collected by clinical and psychophysical examination performed on all patients at the 4th month after surgery will be also considered for analysis, in order to understand better the features of post-thoracotomy neuropathic pain.

Official Title
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Effects of Perioperative Systemic Ketamine on Development of Long-term Neuropathic Pain After Thoracotomy.

Conditions
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Partial Pneumonectomy Under Lateral or Posterolateral Thoracotomy.

Intervention / Treatment
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* Drug: Hypothetica


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: elective partial pneumonectomy under lateral or posterolateral thoracotomy, performed under standardized general anesthesia. Exclusion Criteria: Patient's refusal Bad health status Previous neuropathic pain or treatment acting on neuropathic pain Major postoperative complication Intolerance to ketamine Epidural anesthesia

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 75 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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: ketamine<br>This study compares two groups of patients undergoing thoracotomy for partial pneumonectomy, one receiving intravenous ketamine since the beginning of procedure and then during 48 hours, the other receiving inactive normal saline (placebo). | Drug: Hypothetica<br> <br> |
| Other: placebo<br>This study compares two groups of patients undergoing thoracotomy for partial pneumonectomy, one receiving intravenous ketamine since the beginning of procedure and then during 48 hours, the other receiving inactive normal saline (placebo). | Drug: Hypothetica<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reduction of chronic pain |  |  | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reduction of signs of neuropathic pain. |  |  | 
| Improvement of quality of life. |  |  | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Thoracotomy, Neuropathic pain, Nerve trauma, Ketamine, NMDA receptors