Such interventions would have the potential to reduce the prevalence of chronic pain in the population .
Although certain risk factors can identify individuals who are most likely to develop chronic pain , few interventions to prevent chronic pain have been identified .
To facilitate the identification of preventive interventions , an IMMPACT meeting was convened to discuss research design considerations for clinical trials investigating the prevention of chronic pain .
We present general design considerations for prevention trials in population s that are at relatively high risk for developing chronic pain .
High dose alfentanil pre-empts pain after abdominal hysterectomy
& NA ; This study tested the hypothesis that high dose systemic alfentanil administered before and during abdominal hysterectomy would pre‐empt post‐operative pain to a greater extent than administration of either low dose alfentanil or no alfentanil perioperatively . Patients ( ASA 1 or 2 ) were r and omly assigned to group 1 ( n = 15 ) , no opioid ; group 2 ( n = 15 ) , low dose alfentanil ; or group 3 ( n = 15 ) , high dose alfentanil . Anaesthesia was induced in group 1 with midazolam and thiopentone and was maintained with isoflurane and 70 % N2O in O2 . Anaesthesia was induced in group 2 with midazolam , thiopentone and i.v . alfentanil ( 30 & mgr;g kg−1 ) , and was maintained with isoflurane , 70 % N2O in O2 , and bolus doses of i.v . alfentanil ( 10–20 & mgr;g kg−1 ) every hour . Anaesthesia was induced in group 3 with midazolam and i.v . alfentanil ( 100 & mgr;g kg−1 ) , and was maintained with 70 % N2O in O2 , and an infusion of i.v . alfentanil ( 1–2 & mgr;g kg−1 min−1 ) . Blood sample s were drawn at 30 and 120 min after surgery and assayed for plasma alfentanil . Morphine consumption and VAS pain scores were consistently lowest in group 3 over the 48 h study period . A composite measure of pain and morphine consumption was significantly lower in group 3 than group 2 up to 6 h after surgery , and siificantly lower than group 1 up to 12 h. No adverse effects were observed . A 6‐month follow‐up did not reveal any significant differences among the three groups . It is concluded that intra‐operative high dose alfentanil anaesthetic pre‐empts post‐operative pain after abdominal hysterectomy , but the effects are small and of short duration . Surgical procedures carried out under general anaesthesia using st and ard ( and even high ) doses of opioids intraoperatively provide sub‐optimal protection from the injury barrage brought about by incision and subsequent noxious surgical events
Such interventions would have the potential to reduce the prevalence of chronic pain in the population .
Although certain risk factors can identify individuals who are most likely to develop chronic pain , few interventions to prevent chronic pain have been identified .
To facilitate the identification of preventive interventions , an IMMPACT meeting was convened to discuss research design considerations for clinical trials investigating the prevention of chronic pain .
We present general design considerations for prevention trials in population s that are at relatively high risk for developing chronic pain .