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F J Mercier

Publications and source records attributed to F J Mercier.

At least 19 recordsLinked to original sources
PubMed2005

[Epidural anaesthesia and lumbar tattoo: what to do?].

More and more often, the anaesthesiologist may have to perform lumbar epidural anaesthesia in a patient with a central lumbar tattoo, and this can occur in an urgent obstetric setting. Before managing two uneventful cases of epidural analgesia for labour, we have performed a literature review and noted that no serious complication has been reported. Nonetheless, a needle passed through a tattoo can entrap pigmented tissue fragments (cores) into the epidural or subarachnoid space. This could theoretically induce risk of late neurological complications, related to an inflammatory or granulomatous response to the pigmented cores introduced in these spaces. To avoid this theoretical risk, the anesthesiologist should try to avoid puncturing through the tattoo, either by selecting a different vertebral interspace, or by using a paramedian approach or by finding a pigment free skin spot within the area of the tattoo. When these options cannot be implemented, a superficial skin incision prior to needle insertion should prevent from coring tattoo pigment when entering the skin. Whatever the final choice, the technique to be implemented should be determined as early as the antenatal visit, after informed consent.

Adult↗
PubMed2005

[Alternative techniques to labour epidural analgesia].

Many systemic techniques, so-called "alternatives" to labor epidural analgesia, have been described: they are all poorly effective and some are associated with significant maternal and neonatal side effects. Nonetheless, these techniques can provide good maternal satisfaction. Accordingly, they are indicated when epidural analgesia is contraindicated or unavailable. Administration of systemic opioids mandates maternal respiratory supervision, oxygen supplementation and/or pulse oxymetry. Systemic opioids may also decrease fetal heart rate variability and produce neonatal respiratory depression; naloxone administration to the neonate is therefore widely indicated. Pethidine should be abandoned because it can produce prolonged neonatal respiratory depression. Nalbuphine produces less nausea/vomiting and less long lasting neonatal respiratory depression. Intravenous PCA fentanyl or sufentanil is presently the method of choice during early labor. Alfentanil seems less effective and may produce more neonatal side effects. Intravenous PCA remifentanil is the most effective technique, but safe administration may be problematic during intermittent supervision usually implemented in labour ward. Nitrous oxide 50% provides little pain relief. Nonetheless, it is associated with few side effects, quite good maternal satisfaction and can be quickly implemented during advanced painful labor. It is not recommended to add it to systemic opioid (except under continuous supervision by the anaesthetic team), because of an increased incidence of maternal desaturation. The use of a subanaesthetic concentration of sevoflurane has been described recently; it is more effective than nitrous oxide. However, guidelines for safe implementation in labor ward remain to be determined.

Adult↗
PubMed2004

The human near-term myometrial beta 3-adrenoceptor but not the beta 2-adrenoceptor is resistant to desensitisation after sustained agonist stimulation.

1. In order to compare the beta(2)- and beta(3)-adrenoceptor (beta-AR) desensitisation process in human near-term myometrium, we examined the influence of a pretreatment of myometrial strips with either a beta(2)- or a beta(3)-AR agonist (salbutamol or SR 59119A, respectively, both at 10 microm, for 5 and 15 h) on the relaxation and the cyclic adenosine monophosphate (cAMP) production induced by these agonists. 2. To assess some of the mechanisms potentially implicated in the beta-AR desensitisation process, we studied the influence of such treatment on the number of beta(2)- and beta(3)-AR binding sites, the beta(2)- and beta(3)-AR transcripts expression and the phosphodiesterase 4 (PDE4) activity. 3. Salbutamol, but not SR 59119A, concentration-response curve (CRC) was shifted by a 15 h salbutamol preincubation, with a significant difference in -log EC(20) values (6.31+/-0.13 vs 5.58+/-0.24, for control and 15 h salbutamol pretreatment, respectively, P<0.05). Neither salbutamol nor SR 59119A CRCs were modified after a 15 h preincubation with SR 59119A. 4. A 15 h exposure of myometrial strips to salbutamol significantly reduced the salbutamol-induced (0.60+/-0.26 vs 1.54+/-0.24 pmol mg(-1) protein, P<0.05), but not the SR 59119A-induced, cAMP production. No decrease in cAMP production was observed after a 15 h SR 59119A exposure. 5. A 15 h salbutamol exposure of myometrial strips significantly reduced the beta(2)- but not the beta(3)-AR binding site density, whereas no decrease in the number of beta(2)- and beta(3)-AR binding sites was observed after a 15 h SR 59119A treatment. 6. Neither PDE4 activity nor the beta(2)- and beta(3)-AR mRNA expression levels were affected by salbutamol or SR 59119A treatments. 7. Our results indicate that beta(3)-AR, but not beta(2)-AR, are resistant to the agonist-induced desensitisation. In our model, beta(2)-AR desensitisation is mediated by a decreased number of beta(2)-AR that was not explained by transcriptional regulation of the receptor.

Adrenergic beta-2 Receptor Agonists↗
PubMed2004

Acid aspiration prophylaxis in obstetrics in France: a comparative survey of 1998 vs. 1988 French practice.

BACKGROUND AND OBJECTIVE: To survey French anaesthetic practice regarding acid aspiration prophylaxis and compare it with an earlier survey. METHODS: A confidential questionnaire was sent to all 800 maternity units in France to assess three major topics: (a) drugs used for pharmacological prophylaxis; (b) regional anaesthesia for labour and Caesarean section and (c) techniques used for general anaesthesia and endotracheal intubation. RESULTS: Two-hundred-and-two units responded. Pharmacological prophylaxis was regularly used for labouring women in 78% of the responding units in 1998 (compared with 63% in 1988, P < 0.05). Antacid drug use before Caesarean section had increased from 75% in 1988 to 97% in 1998 (P < 0.05). General anaesthesia was used for Caesarean section by less than 2% of responding units (vs. 21% in 1988, P < 0.05). In contrast, there was little change in the use of endotracheal intubation for instrumental delivery (53% vs. 50%) or manual removal of the placenta (15% vs. 16%) between 1988 and 1998. The use of cricoid pressure increased significantly during the 10 yr period (50% vs. 88%, P < 0.05) and the technique was correctly described by 80% of the responding units (vs. 50%, P < 0.05). Similarly, the use of succinylcholine increased significantly from 25% (1988) to 479 (1998) (P < 0.05). CONCLUSIONS: There was a significant overall improvement of French practice regarding acid aspiration prophylaxis in obstetrics. However, the complete prophylaxis strategy is still not used in every patient emphasizing the need for continuing medical education.

Anesthesia, Conduction↗
PubMed2003

[Is obstetric epidural anaesthesia technically possible after spinal surgery and does it work?].

OBJECTIVE: Previous spine surgery theoretically exposes the obstetric patient to a greater technical difficulty during regional analgesia for labour or during anaesthesia for caesarean delivery. Published experience suggests that epidural puncture is however technically possible in the majority of cases. STUDY DESIGN: Retrospective study. PATIENTS: Analysis of the files of parturients who gave birth in a maternity hospital during a six year period and who had previously undergone spine surgery. METHODS: Technical failures (during puncture), analgesic failures (complete block inefficiency and/or requirement of a general anaesthetic) and complications (important bleeding at the puncture site, dural tap, infection) observed during epidural analgesia/anaesthesia were recorded. RESULTS: Except for two paraplegic parturients who had been operated for dorsocervical traumatic injuries and who were excluded from the analysis, 31 parturients had undergone spine surgery and delivered during the period of analysis. Twenty patients underwent 22 epidural punctures. Technical failure were noted in two cases (9%) and analgesic failure in two other cases (9%). No significant complication was recorded. CONCLUSION: With an overall 18% failure rate, epidural anaesthesia is not contra-indicated in these patients but appears to be less reliable than in patients with normal spine. Psychological and technical preparation to the occurrence of failure is necessary.

Adult↗
PubMed2003

Efficacy of augmentation of epidural analgesia for Caesarean section.

BACKGROUND: Extension of a labour epidural for Caesarean delivery is thought to be successful in most cases and avoids the use of general anaesthesia. However, most previous studies that have estimated the failure rate of pre-existing epidural catheters were performed in small numbers of patients. METHODS: Therefore, we undertook to retrospectively measure the failure rate of indwelling epidural catheters in a large number of patients. RESULTS: The anaesthetic team was available at all times and was permanently led by a senior anaesthetist specialized in obstetrics. Extension was performed using lidocaine 2% with epinephrine (mean 18 (SD 6) ml), combined in most patients with sufentanil (9 (2.2) microg) and/or clonidine (75 microg). Among 194 consecutive extensions performed in a 1-yr period, general anaesthesia was required in five patients (2.6%) while sedation and/or i.v. analgesia were used in 27 patients (13.9%). In three cases where general anaesthesia was required, the interval between decision to incision was <10 min. No factor associated with failure could be identified. Addition of a lipophilic opioid or of clonidine did not modify the efficacy of the block (i.e. general anaesthesia or supplementation were required in a similar proportion). CONCLUSIONS: The augmentation of labour epidurals for Caesarean section using lidocaine 2% plus epinephrine is a reliable and effective technique. No factor associated with failure could be identified.

Adjuvants, Anesthesia↗
PubMed2002

Continuous epidural analgesia with bupivacaine 0.125% or bupivacaine 0.0625% plus sufentanil 0.25 microg.mL(-1): a study in singleton breech presentation.

Epidural analgesia is the most efficient technique for labor pain relief. However, its resultant motor block might impair the mode of delivery, particularly in breech presentation where the risk of dystocia is high. In this trial, we compared bupivacaine 0.125% with a combination of a low concentration of bupivacaine (0.0625%) and sufentanil (0.25 microg.mL(-1)) both administered by continuous infusion. Analgesia, maternal and fetal/neonatal side effects and obstetric outcome were compared between group bupivacaine (n = 23) and group bupivacaine-sufentanil (n = 35). A greater number of patients in the bupivacaine 0.125% group required more than two top-ups (32 vs. 8% of patients, P = 0.03) while pain scores were similar. Motor block at delivery was more pronounced in the bupivacaine 0.125% group. Nausea and pruritus were more often encountered in the bupivacaine-sufentanil group. There was a trend toward a decreased rate of assisted or operative delivery in the bupivacaine-sufentanil group (92% vs. 74%, P = 0.09). Fetal/neonatal data did not differ between groups. Epidural analgesia with bupivacaine-sufentanil required fewer additional top-ups and produced less motor block than did bupivacaine 0.125%. However, there was no significant difference in mode of delivery between the two analgesic regimens.

Journal Article↗
PubMed2002

Relaxation of proximal and distal isolated human bronchi by halothane, isoflurane and desflurane.

Volatile anaesthetics relax airway smooth muscle in vitro. The amount of relaxation might depend on the type and concentration of volatile anaesthetics, the calibre and precontraction level of the bronchi, and also on the species considered. These effects were investigated on isolated human bronchi. Isometric relaxations produced by halothane, isoflurane and desflurane bubbled on human bronchial rings precontracted with carbachol were recorded and compared with time controls. Volatile anaesthetics induced a concentration-dependent relaxation at 0.66, 1.33 and 2 minimum alveolar concentration (MAC). The relaxation was greater in mildly (carbachol 3x10(-7) M) than in highly (carbachol 2x10(-6) M) precontracted bronchi. Halothane was more potent in relaxing distal as compared to proximal bronchi; this differential effect was less pronounced with isoflurane and not observed with desflurane. While the three volatile anaesthetics induced similar relaxation on proximal bronchi, halothane was significantly more potent than desflurane on distal bronchi, with isoflurane being intermediate. The relaxation induced by 1.33 MAC of halothane, isoflurane and desflurane on moderately precontracted distal bronchi (carbachol 1x10(-6) M) was attenuated by pretreatment with glibenclamide 1x10(-5) M. In conclusion, halothane, isoflurane and desflurane exert direct but differential relaxant effects on human isolated bronchial smooth muscle. This may provide supplemental bronchodilation during anaesthesia. Although adenosine triphosphate-sensitive K+ channels are involved in these relaxant effects, they are unlikely to explain the observed differences between the three volatile anaesthetics.

Anesthetics, Inhalation↗
PubMed2001

[Maternal serum anti-D antibody concentration monitoring and transfusion practices in obstetrics in France: a preliminary study].

OBJECTIVES: In obstetrics, transfusion medicine is involved because of the risk of Rh isoimmunisation and of transfusion at delivery. In France, although these two situations have led to legal or professional recommendations, practices appear to be very different from one institution or one physician to another. STUDY DESIGN: Retrospective study. METHODS: A questionnaire using both direct questions and clinical cases was sent to all members of the French obstetric anaesthetists association (named CARO). RESULTS: One hundred and seventy-eight questionnaires (response rate 17.1%) were returned. Monitoring of anti-D antibody concentrations during pregnancy was performed in accordance with the legal recommendation (14/02/1992) in only 3.9% (Rh+) and 19% (Rh-) of women. Blood samples were performed either too often or too rarely in 39 to 72% of responses. At delivery, an immediate assessment of anti-D antibody concentration was required in almost 100% by the specialist on call in the blood bank while this measurement was considered necessary by only 80% of anaesthetists responding to the questionnaire. The distance between the maternity and the blood bank is greater than 14 km in 19% of responses and the largest time interval reported to obtain red cell concentrates was greater than 145 min in 18% of responses. Autologous blood transfusion is described as being used routinely in only 23% of responses. CONCLUSION: Significant failures in practice patterns and organisation of care are suggested by the responses to this questionnaire. This should stimulate a national debate to improve adequacy of practices to legal and professional recommendations and to review blood distribution to maternities in this country.

Adult↗
PubMed2001

[Obstetric analgesia in patients with Klippel-Trenaunay syndrome].

We report three cases of delivery in two parturients with a Klippel-Trenaunay syndrome. These patients have a rare hereditary disorder that results in three main features: haemangiomas, varicose veins, bone and soft tissue hypertrophy. In the absence of angiographic magnetic resonance imaging of the spinal cord and of perispinal tissues, arteriovenous malformations of the central nervous system could not been ruled out. Intravenous sufentanil and pudendal block were used for labour analgesia and vaginal delivery respectively; general anaesthesia was used for uterine revision and for caesarean section.

Adult↗
PubMed2001

Phenylephrine added to prophylactic ephedrine infusion during spinal anesthesia for elective cesarean section.

BACKGROUND: Because ephedrine infusion (2 mg/min) does not adequately prevent spinal hypotension during cesarean delivery, the authors investigated whether adding phenylephrine would improve its efficacy. METHODS: Thirty-nine parturients with American Society of Anesthesiologists physical status I-II who were scheduled for cesarean delivery received a crystalloid preload of 15 ml/kg. Spinal anesthesia was performed using 11 mg hyperbaric bupivacaine, 2.5 microg sufentanil, and 0.1 mg morphine. Maternal heart rate and systolic blood pressure were measured at frequent intervals. A vasopressor infusion was started immediately after spinal injection of either 2 mg/min ephedrine plus 10 microg/min phenylephrine or 2 mg/min ephedrine alone. Treatments were assigned randomly in a double-blind fashion. The infusion rate was adjusted according to systolic blood pressure using a predefined algorithm. Hypotension, defined as systolic blood pressure less than 100 mmHg and less than 80% of baseline, was treated with 6 mg ephedrine bolus doses. RESULTS: Hypotension occurred less frequently in the ephedrine-phenylephrine group than in the ephedrine-alone group: 37% versus 75% (P = 0.02). Ephedrine (36+/-16 mg, mean +/- SD) plus 178+/-81 microg phenylephrine was infused in former group, whereas 54+/-18 mg ephedrine was infused in the latter. Median supplemental ephedrine requirements and nausea scores (0-3) were less in the ephedrine-phenylephrine group (0 vs. 12 mg, P = 0.02; and 0 vs. 1.5, P = 0.01, respectively). Umbilical artery pH values were significantly higher in the ephedrine-phenylephrine group than in the group that received ephedrine alone (7.24 vs. 7.19). Apgar scores were similarly good in both groups. CONCLUSION: Phenylephrine added to an infusion of ephedrine halved the incidence of hypotension and increased umbilical cord pH.

Adult↗
PubMed2000

[Auditing of drug use practices in anesthesia].

OBJECTIVES: Internal pharmaceutical practice guidelines were produced in a department of anaesthesia of a University hospital in 1995, after a preliminary evaluation showing controversial and expensive practices. After approval, these recommendations were circulated to all members of the department. Phase I of this study was started 18 months later, to evaluate the compliance of anaesthetists with these guidelines. STUDY DESIGN: Prospective survey. METHOD: An audit was performed by a research assistant pharmacist, previously trained, who compared anaesthetic agents and fresh gas flows used during anaesthetics with those recommended in the internal guidelines. RESULTS: Implementation of guidelines was observed in more than 90% of cases for all agents studied, except for non-depolarizing neuromuscular relaxants. Relaxants of intermediate duration were used in 52% of cases with an expected surgery duration of more than 90 min, in opposition to the guidelines stating that pancuronium should have been administered in such circumstances. These results were presented and discussed. Slight changes in the guidelines (especially concerning monitoring of neuromuscular blockade) were made and evaluated again, using the same method (Phase II). A small but significant improvement was seen with induction agents (use of propofol in non-approved situations: 5 versus 0%, P = 0.03), while a non significant trend toward better implementation of guidelines was seen with non-depolarizing agents (use of pancuronium in surgery of expected duration > 90 min: phase I vs phase II = 47 vs 52%, NS; use of pancuronium in surgery of expected duration < 90 min: phase I vs phase II = 3.5 vs 0%, NS). CONCLUSION: This study suggests that implementation of internal guidelines is easy when clinical indications of the agents are not controversial.

Anesthetics↗
PubMed1999

Pharmacological and biochemical study on the effects of selective phosphodiesterase inhibitors on human term myometrium.

This study was aimed at evaluating the in vitro effects of phosphodiesterase inhibitors and beta2-adrenoceptor agonists on spontaneous contractions of human term myometrium. Rolipram, RP 73401 (3-cyclopentyloxy-N-(3,5(-dichloro-4-pyridil)-4-methoxybenzamide) and Ro 20-1724 (1-4-(3-butoxy-4-methoxybenzyl)-2-imidozolidinone) (phosphodiesterase 4 inhibitors) inhibited spontaneous myometrial contractions (Emax approximately 100%; pD2 of 6.80+/-0.28, 6.84+/-0.32 and 6.31+/-0.03, respectively). Salbutamol and formoterol were less effective (Emax=40+/-6% and 35+/-12%, respectively) than phosphodiesterase 4 inhibitors to reduce myometrial contractility. Inhibitors of phosphodiesterase 3 (milrinone and siguazodan) and 5 (zaprinast) were marginally effective. Rolipram (10-30 nM) and siguazodan (0.1 microM) potentiated the response to salbutamol (Emax=75+/-12%, 88+/-8% and 73+/-12% and pD2=6.51+/-0.20, 6.93+/-0.29 and 6.48+/-0.16, respectively). Sodium nitroprusside (pD2=6.76+/-0.29) and theophylline (pD2=5.15+/-0.22) were effective inhibitors of myometrial contractions. Chromatographic separation of phosphodiesterase isoenzymes demonstrated that phosphodiesterase 4 is predominant but other phosphodiesterase isoenzymes were also identified. In conclusion, phosphodiesterase 4 inhibitors alone or combined with beta2-adrenoceptor agonists have potential interest as tocolytic agents.

Adrenergic beta-Agonists↗
PubMed1999

[Learning placement of a new oropharyngeal intubation (Copa)].

OBJECTIVE: To assess learning of Copa (cuffed oropharyngeal airway) technique required for insertion and manual ventilation. STUDY DESIGN: Open prospective clinical study. PERSONS: Four staff members, two anaesthetists and two nurse anaesthetists and 74 ASA I or II patients without difficult intubation criteria presenting for minor surgery in the supine position under general anaesthesia. METHODS: After induction of anaesthesia, the Copa was inserted by each doctor and nurse in at least 16 patients and the ventilation manually assisted until spontaneous breathing resumed. RESULTS: The success rate of insertion at the first attempt was 97%. Therefore no learning period was required. Two laryngospasms and two episodes of cough occurred during Copa placement. Additional manipulations to optimise the ventilation were needed in 48 patients. CONCLUSION: Copa is easy to use without previous training. Further studies are required to assess its side effects and the appropriate depth of anaesthesia required for its insertion.

Adult↗
PubMed1999

Haemodynamic changes associated with portal triad clamping are suppressed by prior hepatic pedicle infiltration with lidocaine in humans.

Portal triad clamping (PTC) reduces venous return of blood to the heart. However, the decrease in cardiac index (CI) is associated with an unexpected increase in mean arterial pressure (MAP) and the 40% increase in systemic vascular resistance is greater than anticipated in compensation for the 10% decrease in CI. We hypothesized that a reflex elicited in the peritoneum accounted for this unanticipated haemodynamic response. Twenty patients undergoing liver resection were allocated randomly to have hepatic pedicle infiltration before PTC with either lidocaine 200 mg or placebo. MAP was recorded, and plasma osmolality and plasma concentrations of vasopressin, epinephrine, norepinephrine, dopamine, renin and endothelin were measured. After PTC, MAP increased significantly in the placebo group but decreased significantly in the lidocaine group. Plasma concentrations of vasopressin, epinephrine and norepinephrine increased significantly in the placebo group. Plasma concentrations of vasopressin decreased significantly in the lidocaine group, while plasma concentrations of epinephrine and norepinephrine were unchanged. A subsequent study in eight patients found that neither haemodynamic nor hormonal changes associated with PTC in the placebo group were altered by administration of lidocaine 200 mg i.m. before PTC.

Adolescent↗
PubMed1999

Reduction of blood loss and transfusion requirement by aprotinin in posterior lumbar spine fusion.

UNLABELLED: Aprotinin reduces blood loss in many orthopedic procedures. In posterior lumbar spine fusion, blood loss results primarily from large vein bleeding and also occurs after the wound is closed. Seventy-two patients undergoing posterior lumbar spine fusion were randomly assigned to large-dose aprotinin therapy or placebo. All patients donated three units of packed red blood cells (RBCs) preoperatively. Postoperative blood loss was harvested from the surgical wound in patients undergoing two- and/or three-level fusion for reinfusion. The target hematocrit for RBC transfusion was 26% if tolerated. Total (intraoperative and 24 h postoperative) blood loss, transfusion requirements, and percentage of transfused patients per treatment group were significantly smaller in the aprotinin group than in the placebo group (1935 +/- 873 vs 2809 +/- 973 mL per patient [P = 0.007]; 42 vs 95 packed RBCs per group [P = 0.001]; 40% vs 81% per group [P = 0.02]). Hematological assessments showed an identically significant (a) intraoperative increase in both thrombin-antithrombin III complexes (TAT) and in activated factor XII (XIIa) and (b) decrease in activated factor VII (VIIa), indicating a similar significant effect on coagulation in patients of both groups (P = 0.9 for intergroup comparisons of postoperative VIIa, XIIa, and TAT). Intraoperative activation of fibrinolysis was significantly less pronounced in the aprotinin group than in the placebo group (P < 0.0001 for intergroup comparison of postoperative D-dimer levels). No adverse drug effects (circulatory disturbances, deep venous thrombosis, alteration of serum creatinine) were detected. Although administered intraoperatively, aprotinin treatment dramatically reduced intraoperative and 24-h postoperative blood loss and autologous transfusion requirements but did not change homologous transfusion in posterior lumbar spine fusion. IMPLICATIONS: In our study, aprotinin therapy significantly decreased autologous, but not homologous, transfusion requirements in posterior lumbar spine fusion.

Adult↗