Search PubMed⌕ Search

Biomedical subjects

M Lamy

Publications and source records attributed to M Lamy.

At least 19 recordsLinked to original sources
PubMed2006

New approaches and old controversies to postoperative pain control following cardiac surgery.

OBJECTIVE: To evaluate the effect of postoperative pain control in cardiac surgical patients on morbidity, mortality and other outcome measures. BACKGROUND: New approaches in pain control have been introduced over the past decade. The impact of these interventions, either alone or in combination, on perioperative outcome was evaluated in cardiac surgical patients. METHODS: We searched Medline for the period of 1980 to the present using the key terms analgesics, opioid, non-steroidal anti-inflammatory drugs, cardiac surgery, regional analgesia, spinal, epidural, fast-track cardiac anaesthesia, fast-track cardiac surgery, myocardial ischaemia, myocardial infarction, postoperative care, accelerated care programmes, postoperative complications, and we examined and discussed the articles that were identified to be included in this review. RESULTS: Pain management in cardiac surgery is becoming more important with the establishment of minimally invasive direct coronary artery bypass surgery and fast-track management of conventional cardiac surgery patients. Advances have been made in this area and encompass specific techniques, such as central neuraxial blockade or selective nerve blocks, and drugs (opioids, sedative-hypnotics and non-steroidal anti-inflammatory drugs). Ideally, these therapies provide not only patient comfort but also mitigate untoward cardiovascular responses, pulmonary responses, and other inflammatory and secondary sympathetic responses. The introduction of these newer approaches to perioperative care has reduced morbidity, but not mortality, in cardiac surgical patients. CONCLUSIONS: Understanding perioperative pathophysiology and implementation of care regimes to reduce the stress of cardiac surgery, will continue to accelerate rehabilitation associated with decreased hospitalization and increased satisfaction and safety after discharge. Reorganization of the perioperative team (anaesthesiologists, surgeons, nurses and physical therapists) will be essential to achieve successful fast-track cardiac surgical programmes. Developments and improvements of multimodal interventions within the context of 'fast-track' cardiac surgery programmes represents the major challenge for the medical professionals working to achieve a 'pain and risk free' perioperative course.

Analgesia↗
PubMed2006

The use of pre-operative intrathecal morphine for analgesia following coronary artery bypass surgery.

With the emergence of rapid extubation protocols following cardiac surgery, providing adequate analgesia in the early postoperative period is important. This prospective randomised double-blind study investigated the benefits of pre-operative intrathecal administration of low dose morphine in patients undergoing coronary artery bypass graft surgery. Postoperative analgesia, pulmonary function, stress response and postoperative recovery profile were assessed. Thirty patients were allocated into two groups, receiving either 500 mug of morphine intrathecally prior to anaesthesia and intravenous patient-controlled analgesia with morphine postoperatively following tracheal extubation, or only postoperative intravenous patient-controlled analgesia. In the intrathecal group, the total consumption of intravenous morphine following surgery was significantly reduced by 40% and patients reported lower pain scores at rest, during the first 24 h following extubation. Peak expiratory flow rate was greater and postoperative catecholamine release was significantly lower. Patients in the control group had a higher incidence of reduced respiratory rate following extubation.

Aged↗
PubMed2005

Nitric oxide-related products and myeloperoxidase in bronchoalveolar lavage fluids from patients with ALI activate NF-kappa B in alveolar cells and monocytes.

An increased production of NO* and peroxynitrite in lungs has been suspected during acute lung injury (ALI) in humans, and recent studies provided evidence for an alveolar production of nitrated compounds. We observed increased concentrations of nitrites/nitrates, nitrated proteins and markers of neutrophil degranulation (myeloperoxidase, elastase and lactoferrine) in the fluids recovered from bronchoalveolar lavage fluids (BALF) of patients with ALI and correlated these changes to the number of neutrophils and the severity of the ALI. We also observed that BALFs stimulated the DNA-binding activity of the nuclear transcription factor kappa B (NF-kappaB) as detected by electrophoretic mobility shift assay in human alveolar cells (A549) and monocytes (THP1). The level of activation of the NF-kappaB-binding activity was correlated to the concentration of nitrated proteins and myeloperoxidase. Furthermore, in vitro studies confirmed that NO*-derived species (peroxynitrite and nitrites) and the neutrophil enzyme myeloperoxidase by themselves increased the activation of NF-kappaB, thereby arguing for an in vivo pathogenetic role of NO*-related products and neutrophil enzymes to human ALI.

Biotransformation↗
PubMed2004

[Cerebral functions in brain-damaged patients. What is meant by coma, vegetative state, minimally conscious state, locked-in syndrome and brain death?].

Comatose, vegetative, minimally conscious or locked-in patients represent a problem in terms of diagnosis, prognosis, treatment and everyday management at the intensive care unit. The evaluation of possible cognitive functions in these patients is difficult because voluntary movements may be very small, inconsistent and easily exhausted. Functional neuroimaging cannot replace the clinical assessment of patients with altered states of consciousness. Nevertheless, it can describe objectively how deviant from normal the cerebral activity is and its regional distribution at rest and under various conditions of stimulation. The quantification of brain activity differentiates patients who sometimes only differ by a brief and incomplete blink of an eye. In the present paper, we will first try to define consciousness as it can be assessed at the patient's bedside. We then review the major clinical entities of altered states of consciousness encountered in the intensive care unit. Finally, we discuss the functional neuroanatomy of these conditions as assessed by positron emission tomography (PET) scanning.

Brain Death↗
PubMed2004

[New anesthetic and resuscitation techniques in adult cardiac surgery].

Anesthetic techniques and treatment of cardiac surgery patients have considerably evolved over the past twenty years. The demand for cardiac surgical procedures is increasing. This demand coincides with a change in the profile of patients presenting for surgery, requiring modification in perioperative management strategies. Several new anesthetics, related drugs, and technologies have become available in recent years that inevitably have made new approaches with patient management possible. In parallel to these new developments, there have appeared real opportunities to apply novel physiologic and pharmacologic concepts that may redefine our clinical practice. Fast-tracking, which emphasizes the major role of anesthetic management in postoperative outcome, is one such line of investigation. Fast-tracking was first introduced in an attempt to decrease the time to tracheal extubation and reduce expensive time in intensive care unit areas. Large doses of opioids have been clearly identified as a factor in delaying weaning from mechanical ventilatory support after cardiac surgery. Thus, early investigations emphasized the importance of limiting the dose of potent opioid analgesics during the intraoperative period to achieve early recovery. Supplementation with hypnotic drugs allows reduction of the opioid dose, enabling earlier extubation without compromising hemodynamic stability. Fast track cardiac anesthesia (FTCA) is becoming an accepted practice for perioperative management of cardiac surgical patients. FTCA is a key component to successful conduction of fast-track cardiac surgery. Also, analgesia management in cardiac surgery is becoming more important with the establishment of minimally invasive direct coronary artery bypass surgery and fast track management of conventional cardiac surgery patients.

Analgesics, Opioid↗
PubMed2004

[Peri-anaesthetic anaphylactic shock: myths and facts].

Peri-anaesthetic anaphylactic shock is a fortunately rare event, which nevertheless often turns out to be life-threatening. Only fast recognition and reaction can permit to avoid its sometimes dramatic consequences. This implies, from the anaesthetist, good knowledge of the mechanisms, of the events'sequence, of the usual triggering drugs and, of course, of the anaphylactic shock's treatment. After such an accident has occured the patient should be referred to an allergy specialist in order to perform a thorough exploration, thus pointing out which drug is responsible for the reaction, and by which mechanism. Drugs to be banished in the future would so be identified and should be taken to the patient's as well as his general practician's knowledge.

Anaphylaxis↗
PubMed2003

Bronchoalveolar lavage fluids of ventilated patients with acute lung injury activate NF-kappaB in alveolar epithelial cell line: role of reactive oxygen/nitrogen species and cytokines.

In human alveolar epithelial cell line, we investigated the binding activity of NF-kappaB induced by the bronchoalveolar lavage fluids (BALs) from ventilated patients with acute lung injury (ALI), in correlation with the concentrations of inflammatory cytokines, RNOS, and the severity of the ALI. In BALs obtained in 67 patients (16 bronchopneumonia, 14 infected ARDS, 20 ARDS, and 17 ALI patients without bronchopneumonia and no ARDS), we measured endotoxin, IL-1beta, IL-8, and nitrated proteins (NTP), the activity of myeloperoxidase, and the capacity to activate the NF-kappaB in alveolar A549 cells by electrophoretic mobility shift and supershift assays. The neutrophil counts and mean IL-1beta, IL-8, myeloperoxidase, and NTP values were increased in bronchopneumonia and infected ARDS groups compared to ARDS and ALI without bronchopneumonia and no ARDS groups (P<0.001). The number of neutrophils was correlated to those of IL-1beta, IL-8, myeloperoxidase, NTP, and endotoxin in all groups (P<0.0001). NF-kappaB activity was induced in alveolar like cells by BALs in all groups, was higher in bronchopneumonia and infected ARDS groups (P<0.02), and was correlated to IL-1beta (P=0.0002), IL-8 (P=0.02), NTP (P=0.014), myeloperoxidase (P=0.016), and neutrophil counts (P=0.003). BALs of bronchopneumonia and infected ARDS patients had increased inflammatory mediators (compared to ARDS and ALI without bronchopneumonia and no ARDS patients) that correlated to neutrophil counts and to the NF-kappaB-binding activity. These mediators and NF-kappaB activation may induce an amplification of inflammatory phenomena. By in vitro studies, we confirmed that NO-derived species (10(-6) to 10(-5)M peroxynitrite and 10(-5)M nitrites) and myeloperoxidase (at concentration equivalent to that found in BALs) can participate in the NF-kappaB activation.

Acute Disease↗
PubMed2003

Peripheral vascular surgery: update on the perioperative non-surgical management for high cardiac risk patients.

This review of the recent literature regarding perioperative management in peripheral vascular surgery emphasizes some of the important features for the 2003 state-of-the-art on non surgical perioperative care for these high cardiac risk patients. The most adapted preoperative cardiac evaluation for each patient is guided by its individual risk factors and clinical history. Perioperative medication should nowadays consist of pre- and postoperative beta-blockers and acetyl salicylic acid, both reducing cardiac morbidity and mortality. Neuraxial locoregional anaesthesia techniques are reasonable alternatives to general anaesthesia because of their potential advantages, by reducing postoperative inflammatory response and reducing procoagulating activity, and increasing peripheral vascular graft patency, but the individual benefit/risk balance has always to be evaluated for patients submitted to aggressive antithrombotic therapy. During the postoperative course, early detection and treatment of postoperative myocardial ischemia or infarction by ST wave changes and/or cardiac enzyme control has to be considered.

Comorbidity↗
PubMed2003

Occupational stress and burnout in anaesthesia.

BACKGROUND: Formal studies on stress in anaesthetists have usually measured stress through mental or physiological indicators. When using this approach, one must be careful not to confuse the effects of stress or outcome variables and the sources of stress or antecedent variables. To date, it seems from the literature that there is no clear evidence of a common pattern of physiological effects of stress for all the sources of stress. Furthermore, work characteristics such as job satisfaction, job control and job support may moderate the effects of stress. METHODS: We measured the effects of stress together with the sources of stress and job characteristics, using self-reported questionnaires rather than physiological indicators in order to better diagnose stress in anaesthetists. RESULTS: The mean stress level in anaesthetists was 50.6 which is no higher than we found in other working populations. The three main sources of stress reported were a lack of control over time management, work planning and risks. Anaesthetists reported high empowerment, high work commitment, high job challenge and high satisfaction. However, 40.4% of the group were suffering from high emotional exhaustion (burnout); the highest rate was in young trainees under 30 years of age. CONCLUSIONS: Remedial actions are discussed at the end of the paper.

Adult↗
PubMed2003

Pancreatic injury in equine acute abdomen evaluated by plasma trypsin activity and histopathology of pancreatic tissue.

In cases of equine acute abdominal disease, where pancreatic damage is suspected, pancreatic damage can be assessed by measuring increased trypsin activity in the plasma of horses suffering intestinal obstruction and severe shock. The pancreas is particularly vulnerable to splanchnic hypoperfusion because it is a highly active tissue. In this study, 10 horses undergoing abdominal surgery for intestinal obstruction were assayed for trypsin activity on admission and, because of extensive intestinal lesions that were not amenable to surgery, euthanasia was selected; the pancreas was removed before euthanasia. Trypsin activity in the plasma of these horses was significantly higher than in healthy horses (196 ng/ml +/- 128.2 versus 28.5 ng/ml +/- 19.2; P = 0.0026). Light and transmission electron microscopy revealed slight to severe lesions of vacuolar degeneration, a few zymogen granules, dilation of the endoplasmic reticulum, and swelling of mitochondria in the exocrine pancreas. The activation of an inflammatory cascade occurring during strangulating intestinal obstruction could increase pancreatic anoxic lesions caused by severe shock and hypoperfusion in the horse. Further studies will show the significance of pancreatic lesions and the ensuing damage in equine acute intestinal obstruction and shock.

Animals↗
PubMed2002

Bronchoalveolar lavage fluids of patients with lung injury activate the transcription factor nuclear factor-kappaB in an alveolar cell line.

In bronchoalveolar lavage (BAL) fluid from ventilated patients, cytotoxic oxidant activity is correlated with neutrophil activation. The aim of the present study was to investigate the hypothesis that BAL fluid induces activation of the transcription nuclear factor-kappaB (NF-kappaB) in human alveolar cells, in correlation with inflammatory mediators. We measured endotoxin, inflammatory cytokines [interleukin-1beta (IL-1beta), IL-8], nitrated proteins and the activity of myeloperoxidase (MPO) in BAL fluid from ventilated patients developing bronchopneumonia ( n =19 samples) or with acute respiratory distress syndrome (ARDS) ( n =14), and from ARDS/infection-free patients ( n =11). We also exposed alveolar cells to the BAL fluid or to human MPO, H(2)O(2) or HOCl, and tested nuclear extracts for the activation of NF-kappaB. IL-1beta, IL-8, nitrated protein, MPO and endotoxin levels were significantly higher in BAL fluid from patients with bronchopneumonia than in that from the ARDS and ARDS/infection-free groups. A correlation was observed between IL-8 and MPO values ( r =0.82). The level of NF-kappaB activity induced by the BAL fluid was correlated with levels of IL-1beta ( P <0.001), IL-8 ( P <0.005) and MPO ( P <0.002), and with the neutrophil count ( P <0.002), and was higher for BAL fluid from the bronchopneumonia group. NF-kappaB activation by MPO was also demonstrated. The activation of NF-kappaB by BAL fluid, especially that from bronchopneumonia patients, suggests that a similar phenomenon may occur in vivo, leading to potential amplification of the inflammatory reaction.

Adolescent↗
PubMed2002

Cortical processing of noxious somatosensory stimuli in the persistent vegetative state.

The persistent vegetative state (PVS) is a devastating medical condition characterized by preserved wakefulness contrasting with absent voluntary interaction with the environment. We used positron emission tomography to assess the central processing of noxious somatosensory stimuli in the PVS. Changes in regional cerebral blood flow were measured during high-intensity electrical stimulation of the median nerve compared with rest in 15 nonsedated patients and in 15 healthy controls. Evoked potentials were recorded simultaneously. The stimuli were experienced as highly unpleasant to painful in controls. Brain glucose metabolism was also studied with [(18)F]fluorodeoxyglucose in resting conditions. In PVS patients, overall cerebral metabolism was 40% of normal values. Nevertheless, noxious somatosensory stimulation-activated midbrain, contralateral thalamus, and primary somatosensory cortex in each and every PVS patient, even in the absence of detectable cortical evoked potentials. Secondary somatosensory, bilateral insular, posterior parietal, and anterior cingulate cortices did not show activation in any patient. Moreover, in PVS patients, the activated primary somatosensory cortex was functionally disconnected from secondary somatosensory, bilateral posterior parietal, premotor, polysensory superior temporal, and prefrontal cortices. In conclusion, somatosensory stimulation of PVS patients, at intensities that elicited pain in controls, resulted in increased neuronal activity in primary somatosensory cortex, even if resting brain metabolism was severely impaired. However, this activation of primary cortex seems to be isolated and dissociated from higher-order associative cortices.

Adult↗
PubMed2001

Oxidative processes in human promonocytic cells (THP-1) after differentiation into macrophages by incubation with Chlamydia pneumoniae extracts.

Human monocytes differentiated into macrophages by Chlamydia pneumoniae were able to oxidize blood lipoproteins, as discovered by Kalayoglu et al. (1998). Using a model of human promonocytic cells (THP-1), the cells were differentiated into macrophages by preincubation with C. pneumoniae extract, and further stimulated by phorbol myristate acetate. In these conditions, the differentiated cells oxidized a thiol compound and released superoxide anion as demonstrated respectively by gas liquid chromatography and electron spin resonance. The thiol oxidation and superoxide anion release were inhibited by diphenyliodonium, a NADPH oxidase and NOsynthase inhibitor, proving that the respiratory burst and the NOsynthase were involved in the oxidation processes occurring in the differentiated THP-1. The role of H(2)O(2) (derived from superoxide anion) was indicated by the enhancing effect of a peroxidase on the thiol oxidation. The presence of alpha-tocopherol in the surrounding medium strongly diminished the oxidation of the thiol target.

Anti-Bacterial Agents↗
PubMed2001

Effect of nitrous oxide on the bispectral index and the 95% spectral edge frequency of the electroencephalogram during surgery.

We studied the effect of nitrous oxide on the bispectral index and 95% spectral edge frequency of the electroencephalogram in 20 patients undergoing lumbar surgery under general anaesthesia combined with epidural administration of 5 mg morphine. Anaesthesia was induced with propofol and sufentanil, and maintained with sevoflurane in air/oxygen adjusted to keep the bispectral index between 40 and 60. One and a half hours after the start of surgery, nitrous oxide was administered in a randomised sequence of concentrations (20, 40 and 60% end-expired). Under steady-state conditions, mean (SD) bispectral index and spectral edge frequency decreased as end-tidal concentration of nitrous oxide increased, from 47.7 (4.3) and 15.6 (1.3) at 0% nitrous oxide to 39.8 (6.3) and 14.3 (1.8) at 60% nitrous oxide. A negative correlation was found between nitrous oxide concentration and bispectral index (r = -0.48; p < 0.01) and spectral edge frequency (r = -0.39; p < 0.05). We conclude that this dose-dependent decrease in bispectral index and spectral edge frequency induced by nitrous oxide may reflect the level of analgesia associated with the anaesthetic regimen.

Adult↗