Publications (35) View all
-
Article: Risk factors predictive of chronic postsurgical neuropathic pain: the value of the iliac crest bone harvest model.
[show abstract] [hide abstract]
ABSTRACT: Nerve lesions and secondary hyperalgesia may both be present after surgery, and their relative contributions to chronic postsurgical neuropathic pain (CPSNP) remain unclear. This prospective study explored the roles of these factors in the development of CPSNP after iliac crest bone harvest. CPSNP was defined as pain in the area of hypoesthesia, with a positive Douleur neuropathique 4 questionnaire (DN4) score 3 months after iliac crest bone harvest. The location, intensity, and neuropathic characteristics of pain were evaluated in 82 patients who were followed for 6 months. Neuropathic characteristics were assessed by clinical examination and DN4 questionnaire. The area of secondary hyperalgesia was evaluated 48 h and 1 month after surgery. The area of mechanical hypoesthesia, detection, and mechanical pain threshold were evaluated at 48 h and at 1 and 3 months. Nineteen patients (23%) had CPSNP at 3 months. The patients who developed CPSNP had a larger area of secondary hyperalgesia at 48 h (88 cm(2) vs 33 cm(2); P=.001), higher pain intensity (numerical rating scale 6.7 vs 4.7; P=.02), and higher neuropathic characteristics score on the DN4 questionnaire (4.3 vs 2.3; P=.001). However, neither the area nor the severity of hypoesthesia differed significantly between patients with and without CPSNP. Two independent, additive predictors of CPSNP were identified: area of secondary hyperalgesia (odds ratio 1.02; P=.004) and DN4 score (odds ratio 1.94; P=.001). These findings suggest that both nerve lesions and central sensitization are involved in CPSNP development and could be seen as early warning signs.Pain 05/2012; 153(7):1478-83. · 5.78 Impact Factor -
Article: [Long-term effects of anesthesia].
La Revue du praticien 11/2010; 60(9):1272-4. -
Article: Small fibre impairment predicts neuropathic pain in Guillain-Barré syndrome.
[show abstract] [hide abstract]
ABSTRACT: The mechanisms of neuropathic pain (NP) in Guillain Barré syndrome (GBS) are currently unknown. It has recently been shown that acute neuropathy of GBS not only affects large myelinated fibres but also small nociceptive fibres. In this prospective longitudinal 18 months study, we investigated the role of small fibre impairment in NP in GBS (n=30). Small fibres were assessed by quantifying cold and warm detection and pain thresholds and responses to suprathreshold painful thermal and mechanical stimuli. Nerve conduction velocities and mechanical detection thresholds assessed large myelinated fibres. Detection thresholds particularly at the lower limbs were significantly impaired in patients with GBS compared to 15 healthy controls. GBS patients with NP (n=13) had more severe impairment of cold detection thresholds (p=0.04), heat pain thresholds (p=0.03) and responses to suprathreshold heat stimuli (p=0.017) in the foot compared with those without pain or with non-neuropathic pain (n=17). Large fibre dysfunction and motor disability were similar between groups. Small fibre sensory impairment at the acute stage was correlated with the intensity of burning pain (Rho: -0.72; p=0.01 for cold detection; Rho: 0.72; p=0.02 for heat pain) and predicted residual NP (odds 4.1 p=0.04 for heat pain). These findings emphasize the importance of nociceptive fibre impairment in NP in GBS at both acute and chronic stages and suggest similarities between the mechanisms of NP in GBS and those of small fibre painful sensory polyneuropathies.Pain 10/2010; 151(1):53-60. · 5.78 Impact Factor -
Article: Nefopam and alfentanil additively reduce the shivering threshold in humans whereas nefopam and clonidine do not.
[show abstract] [hide abstract]
ABSTRACT: Induction of therapeutic hypothermia is often complicated by shivering. Nefopam reduces the shivering threshold with minimal side effects. Consequently, nefopam is an attractive component for induction of therapeutic hypothermia. However, nefopam alone is insufficient; it will thus need to be combined with another drug. Clonidine and alfentanil each reduce the shivering threshold. This study, therefore, tested the hypothesis that nefopam, combined either with clonidine or alfentanil, synergistically reduces the shivering threshold. For each combination, ten volunteers were studied on 4 days. Combination 1: (1) control (no drug); (2) nefopam (100 ng/ml); (3) clonidine (2.5 microg/kg); and (4) nefopam plus clonidine (100 ng/ml and 2.5 microg/kg, respectively). Combination 2: (1) control (no drug); (2) nefopam (100 ng/ml); (3) alfentanil (150 ng/ml); and (4) nefopam plus alfentanil (100 ng/ml and 150 ng/ml, respectively). Lactated Ringer's solution (approximately 4 degrees C) was infused to decrease core temperature. Mean skin temperature was maintained at 31 degrees C. The core temperature that increased oxygen consumption to more than 25% of baseline identified the shivering threshold. With nefopam and clonidine, the shivering thresholds were significantly lower than on the control day. The shivering threshold decreased significantly less than would be expected on the basis of the individual effects of each drug (P = 0.034). In contrast, the interaction between nefopam and alfentanil on shivering was additive, meaning that the combination reduced the shivering threshold as much as would be expected by the individual effect of each drug. Nefopam and alfentanil additively reduce the shivering threshold, but nefopam and clonidine do not.Anesthesiology 08/2009; 111(1):102-9. · 5.36 Impact Factor -
Article: Antiinflammatory effect of peripheral nerve blocks after knee surgery: clinical and biologic evaluation.
[show abstract] [hide abstract]
ABSTRACT: Nerve blocks provide analgesia after surgery. The authors tested whether nerve blocks have antiinflammatory effects. Patients had combined sciatic (single-shot) and continuous femoral block (48 h) (block group) or morphine patient-controlled analgesia after total knee arthroplasty. Pain at rest and upon movement was monitored at 1 (D1), 4 (D4), and 7 days (D7) and 1 (M1) and 3 months (M3) after surgery. Knee inflammation was evaluated (skin temperature, knee circumference) before surgery and at D1, D4, D7, M1, and M3. Plasma cytokine concentrations (interleukin [IL]-6, IL-1beta, tumor necrosis factor [TNF], IL-10, soluble receptor 1 of TNF [sTNF-R1]) were measured before surgery and at 4 h, D1, D4, and D7 after surgery. Capsule and synovial membrane cytokines were measured (IL-6, TNF, IL-1, IL-10). Knee flexion was evaluated before surgery and at D1, D4, D7, M1, and M3. Morphine use and recovery time to autonomy were monitored. Pain at rest and upon movement was lower in the block group than in patient-controlled analgesia patients between D1 and D7 (analysis of variance, P < 0.005). Knee flexion was improved in the block group for D1 to M1 (analysis of variance, P < 0.0001). Block group patients recovered nonassisted mobilization (t test, P = 0.04) and toilet use (t test, P = 0.03) more rapidly. Knee circumference and skin temperature were lower in the block group between D1 and D7 (analysis of variance, P < 0.05). Synovial membrane IL-1 (P < 0.05) and IL-10 (P < 0.01) increased, and plasma IL-6 and sTNF-R1 peaked at 24 h, with no difference between groups. Nerve blocks inhibited clinical inflammation after total knee arthroplasty, with no change in tissue and plasma cytokine concentrations.Anesthesiology 10/2008; 109(3):484-90. · 5.36 Impact Factor
