Search PubMed⌕ Search

Biomedical subjects

L Brasseur

Publications and source records attributed to L Brasseur.

At least 19 recordsLinked to original sources
PubMed1998

A case of 'pure' dynamic mechano-allodynia due to a lesion of the spinal cord: pathophysiological considerations.

We report the unusual observation of a patient who presented with the single symptom of a very intense, brush-induced allodynia (dynamic mechanical allodynia) which was strictly confined to the left C2 and C3 dermatomes. All investigations, including a cervical spinal MRI, were initially normal. The clinical picture remained stable for several months until the appearance of spontaneous pain and sensory deficits suggestive of a spinal lesion. A second MRI revealed an intraspinal lesion involving the C2-C5 segments. In accordance with other clinical and animal studies, such an observation of a 'pure' dynamic mechano-allodynia suggests that specific mechanisms underlie each component of neuropathic pain. Possible pathophysiological mechanisms are discussed in the light of recent experimental results obtained in animals.

Aged↗
PubMed1998

[The epideiology of postoperative pain].

Postoperative pain, as all types of pain, is a complex phenomenon including sensory, emotional and behavioural factors. The incidence and severity of postoperative pain is very variable between patients and is rather unpredictable. Patients characteristics as well as the types of surgery and anaesthesia will be of importance. Health professionals have a major role to play for improving effectiveness of pain management as well as safety.

France↗
PubMed1998

Effects of gabapentin on the different components of peripheral and central neuropathic pain syndromes: a pilot study.

Anticonvulsants are widely used in the treatment of neuropathic pain, and are assumed to act preferentially on lancinating, shooting pain. In the present study, the effects of gabapentin, a novel anticonvulsant, were evaluated systematically on both spontaneous and evoked pain in 18 patients with peripheral nerve injuries or central lesions. Gabapentin was administered orally in gradually increasing doses up to a maximum of 2,400 mg/day. Evaluations of spontaneous ongoing and paroxysmal pain, allodynia and hyperalgesia were performed at the beginning of the study ('baseline') and 6 weeks after the steady-state dose had been reached. Quantitative sensory tests were used to measure detection and pain thresholds to mechanical and thermal stimuli and the responses to suprathreshold stimuli. Gabapentin induced a moderate and statistically significant relief of ongoing spontaneous pain and was particularly effective in reducing paroxysmal pain. A striking finding was the significant effect on brush-induced and cold allodynia. In contrast, no effects were observed on detection and pain thresholds to static mechanical and hot stimuli. Side effects were generally minor and did not interfere with everyday activities. The present study suggests that gabapentin has preferential antihyperalgesic and/or antiallodynic effects, and is equally effective in pain due to peripheral nerve injuries and central lesions.

Acetates↗
PubMed1997

[Review of current pharmacologic treatment of pain].

Pain is the main reason prompting patients to consult their physicians. In acute conditions, pain has a very particular significance as a warning sign, enabling the physician to attempt a diagnosis. Nevertheless, its detrimental effect upon the individual (even in the case of acute pain) and its cost to society are now widely acknowledged. There can be no doubt about the physical component of pain, but the psychological and social aspects should not be ignored, particularly in the case of chronic pain. There is no single therapeutic approach to pain and, more often than not, successful treatment comprises a combination of several. Pharmacological treatments are undeniably the most common approach. In clinical practice, recent advances have been based upon an improved understanding of 'old' substances such as morphine and, at the same time, research continues in the hope of finding the 'ideal' analgesic-effective in most situations but without adverse effects: this appears to be a somewhat utopian arm at present, considering the number of different causes of pain. An improved understanding of the physiological mechanisms of pain has led, within the field of clinical practice, to several methods of differentiating pain. These depend on whether or not pain responds to morphine, or on the type of pain: pain due to an excess of nociception, pain resulting from deafferentation (caused by damage to nerve pathways) in the central or peripheral nervous system and psychogenic (idiopathic) pain. Likewise, there are several different ways of classifying analgesic treatments: according to the intensity of pain, as with use of the WHO ladder (which is based on the notion of steps) for the treatment of cancer pain; according to the presumed physiopathological mechanism and, in particular, the response to morphine, and according to the presumed central or peripheral mechanism of the drugs. In reality, peripherally acting drugs can also have a central mechanism of action, just as drugs known to have a central mechanism of action can also have peripheral activity. As a result, several therapeutic classes have been identified. Firstly NSAIDs, which act by inhibiting the enzymes that synthesise prostaglandins, cyclooxygenases (COX-1, COX-2), but which also act upon lipo-oxygenases: Their efficacy is interesting, although somewhat limited by both their ceiling effect and the frequent adverse gastrointestinal reactions they produce. Specific inhibitors of COX-2 could well reduce the risk of adverse effects. Opioids constitute the first-line treatment for pain, particularly severe pain. There are several classifications for these drugs. Firstly, weak opioids (such as codeine) and strong opioids (such as morphine) are differentiated. Secondly, a distinction is made between pure agonists (such as morphine), partial agonists (such as buprenorphine), agonist-antagonists (such as nalbuphine) and antagonists (such as naloxone). Finally, agents are distinguished on the basis of their chemical structure (synthetic, semi-synthetic or natural derivatives). These molecules act upon different receptors (mu, delta, kappa, sigma) and, although peripheral mechanisms have been described, their activity occurs mainly at spinal and supraspinal levels. They provide a potent analgesic effect but are also responsible for various adverse effects-nausea, vomiting, sedation, constipation and respiratory depression-which seriously limit their use. As long as the indication is appropriate, these drugs should not be withheld because of fear of dependence or abuse. It has been observed that other adjuvant therapeutic approaches, generally used to treat conditions other than pain, provide pain relief in certain situations. These include corticosteroids, which are-widely used in rheumatology and oncology, and antidepressants, which are frequently used to treat chronic pain, especially that with a neuropathic component. Anti-epileptics are also used, particularly for excrutiating

Adjuvants, Pharmaceutic↗
PubMed1996

[Audit of the management of postoperative pain].

OBJECTIVE: The aim of this study was to assess the incidence and severity of postoperative pain in patients undergoing operations in various surgery clinics in the Assistance Publique des Hôpitaux de Paris (AP-HP) and to evaluate management of pain during the 24 hours following surgery. METHODS: Data from surgical and anesthesia observation sheets and from patient complaints collected in a one-day external audit were obtained for 96 surgery clinics in the AP-HP. RESULTS: At the time of surgery, most patients were receiving opioids, especially fentanyl: low dose ( < 1 microgram/kg/h) was given in 17.1% of the patients and regional anesthesia was used in 13%. In 95% of the cases, postoperative orders were written by anesthesiologists. Initial orders were modified according to patient response in 11.8% of the cases. "On demand" prescriptions were used in 10% of the orders. Patient controlled analgesia and regional analgesia were not routine techniques (2 and 0% respectively). Finally, 37.8% of the patients were given a single prescription of a step-1 drug (e.g. propacetamol i.v.), 25.9% a step-2 drug either alone or in combination with a step-1 drug, and 28.9% of the patients were given strong opioids at least once. CONCLUSIONS: For all types of drugs, dosage level was considered as correct in 86.5% of the cases. For approximately 10% of the opioid prescriptions, an ineffective dose was used. The interval between doses was too long in 54.1% of the prescriptions for at least one drug (e.g. for peripheral analgesia with propacetamol). The incidence of severe pain was 46.4%, especially after abdominal, high urologic and back surgery.

Analgesia↗
PubMed1995

Oncologists and primary care physicians' attitudes toward pain control and morphine prescribing in France.

BACKGROUND: Two representative samples of primary care physicians (N = 600) and medical oncologists (N = 300) in France were surveyed about their attitudes toward and knowledge about cancer pain management. METHODS: The survey was conducted by telephone with a questionnaire based on a model developed by the University of Wisconsin-Madison Pain Research Group. It was designed to assess physicians' estimates of the prevalence of pain among patients with cancer, their practice in prescribing analgesics, their training in cancer pain management, and the quality of care received by cancer patients in their own practice and in France. RESULTS: Barriers to adequate cancer pain management are prevalent and consistently more common among primary care physicians than among medical oncologists. Although 85% of primary care physicians and 93% of medical oncologists express satisfaction with their own ability to manage cancer pain, 76% of primary care physicians and 50% of medical oncologists report being reluctant to prescribe morphine for cancer pain. Both groups cite fear of side effects as their main reason to hesitate to prescribe morphine. Concerns about the risk of tolerance (odds ratio [OR], 1.15-2.52), perceptions that other effective drugs are available (OR, 1.11-2.41), perceptions that morphine has a poor image in public opinion (OR, 0.96-2.07), and the constraints of prescription forms (OR, 1.12-2.26) contribute significantly to physicians' infrequent prescription of morphine, as are being female (OR, 1.01-2.03) and being an older oncologist (OR, 1.09-2.51). CONCLUSIONS: This study (1) confirms the existence among French physicians of attitudinal barriers and knowledge deficits previously reported in other countries that can impede cancer pain management, (2) identifies new barriers to the proper prescription of morphine for cancer pain control, and (3) reveals discrepancies in physicians' attitudes and knowledge about pain control which suggest a need for the systematic evaluation of cancer patients' care.

Adult↗
PubMed1995

Multicentre study of cancer pain and its treatment in France.

OBJECTIVE: To describe the treatment of cancer pain in France and to evaluate the predictive factors for inadequate management. DESIGN: Multicentre, representative cross sectional survey. SETTING: 20 treatment centres, including cancer centres, university hospitals, state hospitals, private clinics, and one homecare setting (in which patients are supported at home). SUBJECTS: 605 patients with cancer. MAIN MEASURES: Patients rated prevalence and severity of pain and functional impairment related to pain. Doctors reported patients' cancer characteristic, performance status, pain severity, and analgesic drugs ordered. RESULTS: 57% (340/601) of patients with cancer reported pain due to their disease, and, of those with pain, 69% (224/325) rated their worst pain at a level that impaired their ability to function. 30% (84/279) were reported as receiving no drugs for their pain. Of the 270 patients in pain for whom information on treatment was available 51% (137/270) were not receiving adequate pain relief, according to an index based on the World Health Organisation's guidelines. French doctors were found to underestimate the severity of their patients' pain. Younger patients, patients without metastatic disease, patients with a better performance status, and patients who rated their pain as more severe than their doctors did were at greater risk for undertreatment of their pain. CONCLUSIONS: In the light of the high prevalence and the severity of pain among patients with cancer, the assessment and treatment of cancer pain in France remain inadequate, emphasising the need for changes in patient care.

Analgesia↗
PubMed1995

[Interactions between opioids and local anesthetics at the level of the dorsal horn of the spinal cord].

For many years, local anaesthetic drugs, given spinally, have been used to control pain after surgery or during parturition. For nearly 20 years, we have known that opioids given by the same way have an analgesic effect. However the later group do not provide satisfactory analgesia in several pain contexts but also give troublesome side effects; local anaesthetics are associated also with side effects. Experimental and clinical studies have shown that the combination of local anaesthetics with opioids provides some degree of synergism, associated with a reduction of side effects. Further studies are needed to confirm the analgesic benefit and the potential decrease of side effects, but also to determine the minimal effective dose regimen in relation with the type of pain.

Analgesics, Opioid↗
PubMed1994

[Introducing patient-controlled analgesia in a private hospital].

Patient controlled analgesia (PCA) is now a well recognized technique for postoperative analgesia. This study reports an experience of 24 months with 768 patients in a French private hospital. The first step was to train the team for this new technique. The second step was to agree on standards of prescription and safety monitoring rules (respiratory rate plus sedation score), as well as on the selection of patients. Analgesia was obtained with self administrated bolus plus a constant infusion (0.5 milligram per hour) of morphine in all patients, and in some with an addition of paracetamol or ketoprofene for a sparing effect on morphine consumption. All patients were returned to their ward, after an initial titration of pain treatment in the recovery room. No major problems occurred during the study period. In 13 patients the respiratory rate decreased to or under 10 c.min-1 without increased sedation and for safety reasons, the PCA was discontinued. PCA is now routinely used postoperatively for a majority of painful procedures in our institution.

Adolescent↗
PubMed1992

[Postoperative analgesia in France. A study of the prescribing doctor's approach].

Every year nearly 4 million surgical procedures are carried out in France: about two thirds of the patients will suffer moderate to severe postoperative pain. Beside the obvious philosophical reasons, purely medical arguments also favour good quality postoperative pain relief. In this country, unlike the situation prevailing in many other countries, anaesthetists are in charge of postoperative pain relief. The survey reported here was carried out by questioning the usual prescribers and it reports their attitudes and practices. The results would show a rather good situation: anaesthetists seem to have an interest in the subject, and the approach looks very satisfactory but these points remain to be proved in practice. There is considerable interest in some drugs, but others are in disgrace for unclear reasons. New methods of administration are not very familiar. We may conclude from this study that a greater awareness of the problem is desirable, that general and specific scientific information should be made available, that clearly defined treatment plans should be established and evaluated regularly, and that financial resources must be envisaged.

Acetaminophen↗
PubMed1992

[Patient-controlled analgesia by the peridural route and classical methods of analgesia].

Patient controlled analgesia was developed to compare drug effects. Later its psychological implications were studied. Drug administration by intravenous or epidural injection has been used. The latter provides relief with much smaller doses. Simultaneous use of opioids and anti-inflammatory drugs enhances the analgesic effects. For pain relief in childbirth, opioids need to be combined with local anaesthetics for best results. Little has been achieved by patient controlled analgesia in the treatment of chronic pain.

Acute Disease↗
PubMed1991

Comparison of continuous epidural bupivacaine infusion plus either continuous epidural infusion or patient-controlled epidural injection of fentanyl for postoperative analgesia.

We compared the postoperative epidural analgesia provided by the continuous epidural infusion of bupivacaine supplemented with patient-controlled injection (PCA) of epidural fentanyl with that provided by a continuous infusion of bupivacaine supplemented with a continuous epidural infusion of fentanyl. Our patient population comprised 16 ASA physical status I or II patients undergoing laparotomy with a midline incision under general anesthesia combined with bupivacaine epidural analgesia. Post-operatively, a continuous epidural infusion of bupivacaine (0.1 mg.kg-1.h-1) was combined with epidural fentanyl given by either (a) PCA (15-micrograms bolus with a lockout interval of 12 min, n = 8) or (b) continuous infusion (1 microgram.kg-1.h-1, n = 8). In the case of inadequate pain relief in the latter group, the fentanyl infusion rate was increased by 10 micrograms/h. Analgesia evaluated by a visual analogue pain score and by a verbal pain score was similarly effective in both groups. The sedation score was also similar in both groups. The total dose of epidural fentanyl administered during the first 24 h was significantly lower in the PCA group than in the continuous infusion group (405 +/- 110 micrograms vs 1600 +/- 245 micrograms, P less than 0.001). The dose of fentanyl given during each 4-h interval ranged between 40 and 160 micrograms in the PCA group and 251 and 292 micrograms in the continuous infusion group. Clinically detectable respiratory depression was not observed in either group. In conclusion, epidural administration of 0.1 mg.kg-1.h-1 bupivacaine combined with fentanyl provides effective postoperative analgesia with a total dose of fentanyl required that is lower when fentanyl is administered by epidural PCA rather than by continuous epidural infusion.

Adult↗
PubMed1987

Impairment of ventilatory function and pulmonary gas exchange in non-smoking coalminers.

Indices of ventilatory function and pulmonary gas exchange in 32 non-smoking coalminers (mean age 38.1) were compared with those of 34 non-smoking steelworkers of similar age. The coalminers had significantly lower forced expiratory volume in 1 s (FEV1) and maximum expiratory flow rates and significantly higher residual volume, but similar vital capacity and indices derived from the single-breath test. Pulmonary diffusing capacity for CO and indices of CO2 exchange were similar in both groups. Arterial partial pressure of O2 (PaO2) was significantly lower and alveolar-arterial O2 difference was significantly higher in coalminers than in controls, both at rest and during exercise. There was no relation between lung function and radiological signs of simple pneumoconiosis (10 coalminers had pneumoconiosis). The differences in FEV1 (0.42 l) and in PaO2 (10 mm Hg) between the two groups are the same or larger than those usually found between smokers and non-smokers. Exposure to coaldust may result in biologically significant alterations of lung function even in the absence of pneumoconiosis.

Adult↗
PubMed1986

[Determination of the standard oxyhemoglobin dissociation curve in horses. Effects of temperature, pH and diphosphoglycerate].

The equine blood oxyhemoglobin dissociation curve has been traced in its entirety in standard conditions and the effects of temperature, pH and 2,3-diphosphoglycerate on this curve have been measured. When compared to that of human blood, the curve showed a higher oxygen affinity of hemoglobin (23.8 +/- 0.8 versus 26.6 mm Hg). The effect of the pH, expressed by d log P50/dpH, was found to be identical in man and horse (-0.47). The effect of temperature, however, expressed by d log P50/dT, proved to be lower in the horse (0.016 versus 0.024). The P50 showed an increase of 1 mm Hg each time 2,3-diphosphoglycerate was experiencing an elevation of 4 mumol/gHb in the horse. The results obtained from this experiment are intended for the replacement of the values related to the human blood which have been found to be somewhat inadequate for the horse blood, when the data of blood gases are given in algorithms.

2,3-Diphosphoglycerate↗