Search PubMed⌕ Search

Biomedical subjects

S Molliex

Publications and source records attributed to S Molliex.

At least 19 recordsLinked to original sources
PubMed2006

Patient-controlled cervical epidural fentanyl compared with patient-controlled i.v. fentanyl for pain after pharyngolaryngeal surgery.

BACKGROUND: Analgesia after pharyngolaryngeal surgery is commonly provided through the i.v. route. The aim of the study was to compare cervical epidural administration of fentanyl with the i.v. route for postoperative analgesia after pharyngolaryngeal surgery. METHODS: In a randomized double-blind study 42 patients received fentanyl via patient-controlled analgesia (PCA) either through the i.v. route (PCA-IV group, n=22) or through the cervical epidural route (PCA-Epid group, n=20). Identical PCA settings were used in the two groups (bolus dose: 1.5 microg kg(-1), bolus: 25 microg, lockout interval: 10 min, maximum cumulative dose: 400 microg per 4 h). Analgesia at rest and during swallowing was evaluated using a visual analogue scale. RESULTS: Analgesia at rest was better in the PCA-Epid group than in the PCA-IV group but only 2 and 6 h after surgery (P<0.02). There was no difference in analgesia during swallowing. Cumulative doses of fentanyl were similar {PCA-Epid group: 1412 microg (912), PCA-IV group: 1287 microg (1200) [median (IQR)]}. The Pa(o(2)) showed a significant decrease between the preoperative and postoperative period, but this decrease was identical in the two groups [PCA-IV-group: 11.47 (2.4) kPa vs 8.27 (0.9) kPa; PCA-Epid group: 11.33 (1.9) kPa vs 9.20 (2.4) kPa for preoperative and postoperative period respectively]. CONCLUSIONS: The study results show that cervical epidural analgesia provides marginally better pain relief at rest with no decrease in the fentanyl consumption. The use of the cervical epidural administration of fentanyl is questionable because of the possible complications of the technique.

Adult↗
PubMed2006

[A case of delayed fat embolism after a vertebral osteosynthesis].

A 37-year-old woman presented an acute respiratory distress syndrome six days after a post-traumatic vertebral osteosynthesis. First, a pulmonary embolism was suspected, and a thrombolysis realised. This diagnosis was secondary excluded, and the diagnosis of probable fatty embolism was established by the bronchoalveolar lavage. So, this case shows a delayed presentation of fatty embolism and permits a discussion about clinical presentation, and diagnosis methods of such pathology.

Acute Disease↗
PubMed2005

[Which doses of anaesthetic agents in centenarian patients? Interest of BIS monitoring].

A 106-year-old female underwent emergency colectomy for peritonitis secondary to ischemic colitis. Following induction of anaesthesia with 18 mg etomidate (0,4 mg/kg), BIS monitoring allowed to perform surgery with an averaged desflurane end-tidal concentration and remifentanil infusion as low as 0.9% and 0.057 microg/kg/minute respectively. The mean BIS value was of 45+/-4 (min = 38, max = 50), systolic arterial pressure was maintained within+/-10% of control values during 72% of anaesthesia duration (160 min) and the maximal drop did not exceed 27%. No adrenergic agent was used. This observation underlined the interest of BIS when anaesthetic requirement are difficult to estimate rapidly.

Aged↗
PubMed2001

Wavelet transform of heart rate variability to assess autonomic nervous system activity does not predict arousal from general anesthesia.

PURPOSE: The relationship between autonomic nervous system (ANS) activity and general anesthesia has been explored. Studies have demonstrated partial recovery of heart rate variability (HRV), representative of ANS activity, in the postoperative period, but the arousal period has not been precisely studied. The goals of this study were to analyze modifications of ANS activity during general anesthesia and, more particularly, around the arousal period, to look for predictors of arousal. METHODS: We analyzed HRV changes using wavelet transform, a time-frequency analysis that, in contrast to Fourier transform, is able to assess abrupt changes of ANS activity. Seventeen patients (mean +/- SD age: 40.9 +/- 16.4 yr) under general anesthesia for hip or knee surgery, were included in the study. The analysis began one hour before anesthesia, focussed on eye opening, and ended three hours after arousal. RESULTS: There was a dramatic decrease in HRV after induction, that extended throughout anesthesia and represented a decrease in global autonomic regulation with, however, a relative predominance of vagal tone. At the moment of eye opening, there was an abrupt change in HRV, representing a sudden shift of ANS balance towards the predominance of sympathetic activity, while none of these indices changed seconds before arousal. CONCLUSIONS: Wavelet analysis of HRV appears to be powerful tool to precisely assess instantaneous changes of HRV during anesthesia. Using this method, there were no identifiable precursory HRV indices of arousal.

Adult↗
PubMed2001

[Target controlled infusion (TCI) anesthesia using propofol. Assessment of training and practice in the operating room].

OBJECTIVE: To evaluate overall awareness of TCI and the need for training in the TCI technique. To assess, among trained anaesthetists, the value of the session and the impact of TCI technique on their working practice. STUDY DESIGN: Two prospective domestic surveys during the first quarter of 1999. METHODS: Three hundred anaesthetists representative of French anaesthetists as a whole, and 336 anaesthetists who had taken part in a training course. RESULTS: The notoriety of TCI was high and greater in the public sector compared with the private sector. Almost 3/4 of anaesthetists believed that training was necessary but only four anaesthetists out of ten TCI users said they had taken part in training sessions. After the training session nine anaesthetists out of ten became TCI users and would have recommended the training course despite the low number and variety of anaesthetic procedures observed during the practical part of training. The main difficulties reported during initial use were the choice of target concentrations and the management of drug interactions. Familiarisation to the technique was rapid (less than 20 procedures). Despite the lack of long experience (< 6 months for more than 2/3 of them), TCI appeared to be more likely used for anaesthesia of average duration. CONCLUSIONS: TCI was perceived to be an innovative concept with a requirement of a specific training. This preliminary appraisal of training sessions was generally satisfactory but underline a need for future training sessions focused on practical aspects.

Anesthesia, Intravenous↗
PubMed2000

Differential effects of halothane and thiopental on surfactant protein C messenger RNA in vivo and in vitro in rats.

BACKGROUND: Pulmonary surfactant is a complex mixture of proteins and phospholipids synthetized by alveolar type II cells. Volatile anesthetics have been shown to reduce surfactant phospholipid biosynthesis by rat alveolar type II cells. Surfactant-associated protein C (SP-C) is critical for the alveolar surfactant functions. Our goal was to evaluate the effects of halothane and thiopental on SP-C messenger RNA (mRNA) expression in vitro in rat alveolar type II cells and in vivo in mechanically ventilated rats. METHODS: In vitro, freshly isolated alveolar type II cells were exposed to halothane during 4 h (1, 2, 4%) and 8 h (1%), and to thiopental during 4 h (10, 100 micrometer) and 8 h (100 micrometer). In vivo, rats were anesthetized with intraperitoneal thiopental or inhaled 1% halothane and mechanically ventilated for 4 or 8 h. SP-C mRNA expression was evaluated by ribonuclease protection assay. RESULTS: In vitro, 4-h exposure of alveolar type II cells to thiopental 10 and 100 micrometer increased their SP-C mRNA content to 145 and 197%, respectively, of the control values. In alveolar type II cells exposed for 4 h to halothane 1, 2, and 4%, the SP-C mRNA content increased dose-dependently to 160, 235, and 275%, respectively, of the control values. In vivo, in mechanically ventilated rats, 4 h of halothane anesthesia decreased the lung SP-C mRNA content to 53% of the value obtained in control (nonanesthetized, nonventilated) animals; thiopental anesthesia increased to 150% the lung SP-C mRNA content. CONCLUSIONS: These findings indicate that halothane and thiopental used at clinically relevant concentrations modulate the pulmonary SP-C mRNA content in rats. In vivo, the additive role of mechanical ventilation is suggested.

Actins↗
PubMed1999

Differential effects of isoflurane and i.v. anaesthetic agents on metabolism of alveolar type II cells.

Alveolar type II (ATII) cells perform many important functions within the lung, including surfactant metabolism. We have investigated the effects of isoflurane and different i.v. anaesthetics on cell metabolism in primary cultures of rat ATII cells. Biosynthesis of phosphatidylcholine, the main phospholipid component of surfactant, was decreased in cells exposed to isoflurane in a dose- and time-related manner. This effect was fully reversible within 2 h after isoflurane removal. Lactate dehydrogenase (LDH) release, an index of cell damage, was increased with isoflurane exposure (1%) over a long incubation period (8-12 h). Enhanced lactate production, reflecting an increase in glycolytic metabolism, was also observed in isoflurane exposed cells. In contrast, metabolism of ATII cells was moderately affected by i.v. anaesthetics. Our data suggest differential metabolism of alveolar homeostasis depending on the anaesthetic agent used.

Anesthetics, Inhalation↗
PubMed1999

Wavelet transform to quantify heart rate variability and to assess its instantaneous changes.

Heart rate variability is a recognized parameter for assessing autonomous nervous system activity. Fourier transform, the most commonly used method to analyze variability, does not offer an easy assessment of its dynamics because of limitations inherent in its stationary hypothesis. Conversely, wavelet transform allows analysis of nonstationary signals. We compared the respective yields of Fourier and wavelet transforms in analyzing heart rate variability during dynamic changes in autonomous nervous system balance induced by atropine and propranolol. Fourier and wavelet transforms were applied to sequences of heart rate intervals in six subjects receiving increasing doses of atropine and propranolol. At the lowest doses of atropine administered, heart rate variability increased, followed by a progressive decrease with higher doses. With the first dose of propranolol, there was a significant increase in heart rate variability, which progressively disappeared after the last dose. Wavelet transform gave significantly better quantitative analysis of heart rate variability than did Fourier transform during autonomous nervous system adaptations induced by both agents and provided novel temporally localized information.

Adrenergic beta-Antagonists↗
PubMed1998

Halogenated anesthetics inhibit Pseudomonas aeruginosa growth in culture conditions reproducing the alveolar environment.

UNLABELLED: We assessed the effects of halogenated anesthetics on Pseudomonas aeruginosa growth in a liquid nutrient broth. Sterile Petri dishes (3.5-cm diameter) were filled with a 1-mL suspension of a Pseudomonas aeruginosa strain and incubated at 37 degrees C. Exposure of bacterial plates to halothane, isoflurane, and enflurane administered at 1 and 2 minimum alveolar anesthetic concentration (MAC) were studied for different exposure times (1, 2, 3, and 4 h) using an airtight chamber. For each time, a control point was obtained. Serial dilutions and agar plates were made, and developed colonies were counted. A significant decrease in bacterial growth was observed from the second hour of exposure to every halogenated anesthetic. For long periods of exposure (3 and 4 h), bacterial growth was significantly reduced in the plates exposed to 2 MAC compared with 1 MAC. The maximal inhibition was observed after a 4-h exposure at 2 MAC and reached 60%, 49%, and 42% for halothane, isoflurane, and enflurane, respectively. We conclude that a decrease in Pseudomonas aeruginosa growth is observed after exposure to halogenated anesthetics, but whether this inhibition is clinically important remains to be demonstrated. IMPLICATIONS: Bacterial pneumonia is a major source of morbidity after general anesthesia. We measured the effects of volatile anesthetics on the growth of Pseudomonas aeruginosa, one of the pathogens most often isolated in hospital-acquired pneumonia. The experiments were performed in vitro in culture conditions reproducing those observed in the alveolar space. Volatile anesthetics inhibited the growth of these bacteria, but the clinical significance of this fact remains to be determined.

Anesthetics, Inhalation↗
PubMed1998

Halothane decreases Na,K-ATPase, and Na channel activity in alveolar type II cells.

BACKGROUND: Halothane alters surfactant biosynthesis and metabolism of alveolar type II cells. In addition to synthesizing surfactant, alveolar type II cells actively transport sodium (Na) from the alveolar space to the interstitium. Na enters the cells through amiloride-sensitive Na channels or Na cotransporters and is extruded by a Na pump. The purpose of this study was to examine the effects of halothane on Na transport activities. METHODS: Epithelial type II cells from adult rat lungs were exposed to halothane concentrations of 1, 2, and 4% from 0.5-4 h. In some experiments, cells that were exposed to 1% halothane for 1 h were allowed to recover after replacement of the medium for 15 and 30 min. Na transport was then evaluated by direct measurement of radiolabeled ions uptake. In addition, the effects of halothane were assessed in the absence of extracellular calcium (Ca) with or without 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid, an intracellular Ca chelating agent. RESULTS: Exposure of epithelial type II cells to halothane reduced the activity of sodium, potassium-adenosine triphosphatase, and amiloride-sensitive Na channels, whereas Na cotransporters were unchanged. The decrease in sodium, potassium-adenosine triphosphatase activity was maximal for 30 min of exposure and reached 50, 42, and 56% for halothane concentrations of 1, 2, and 4%, respectively, and did not change for longer exposure times. This effect was not prevented by either the absence of extracellular Ca or 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid pretreatment. Exposure for 45 min to 1% halothane also decreased Na channel activity by 46%. These effects were completely reversible after 30 min of recovery. CONCLUSIONS: Sodium, potassium-adenosine triphosphatase, and amiloride-sensitive Na channel activities are impaired by halothane in alveolar type II cells in vitro. This inhibition could reduce transepithelial Na transport.

Alanine↗
PubMed1996

Regional anaesthesia for outpatient nasal surgery.

Regional anaesthesia is not used widely for outpatient nasal surgery. The aim of this study was to determine the role of nasociliary and infraorbital nerve block in 24 patients undergoing nasal surgery comprising: cosmetic or reconstructive surgery of the nose and surrounding soft tissue, polypal removal, turbinectomy, reduction of fractured nasal bones, small tumour resection or emergency surgery on isolated facial lacerations. Mild sedation with midazolam 0.03 mg kg-1 was used before anaesthesia. Nasociliary and infraorbital blocks were technically easy to perform, safe and provided good intraoperative conditions. Only minor complications were observed, including local bruising in eight patients and transient diplopia in one patient. No patient received general anaesthesia, but infiltration of local anaesthetic was necessary in four patients because of incomplete anaesthesia in the surgical area. Operative conditions were judged as good or excellent by surgeons in 20 of 24 patients. Twenty of 24 patients were very satisfied or satisfied with anaesthesia. Duration of surgery exceeding 60 min and excessive bleeding in the nasopharynx were the main limiting factors for the use of facial regional anaesthesia.

Adult↗
PubMed1996

Effect of pre- vs postoperative tonsillar infiltration with local anesthetics on postoperative pain after tonsillectomy.

BACKGROUND: Since pre-incisional peritonsillar infiltrations of local anesthetic solutions have been suggested to reduce postoperative pain after tonsillectomy, we compared the efficacy of either pre- or postoperative local anesthetic infiltration upon post-tonsillectomy pain. METHODS: After the induction of general anesthesia, 68 consecutive healthy patients, ranging in age from 8 to 65 years, were randomly allocated to either receive peritonsillar infiltration with 0.25% bupivacaine (group 1) or normal saline (group 2) before incision. A third group (group 3) had their peritonsillar region infiltrated with 0.25% bupivacaine after the completion of surgery but before the patients were awakened from anesthesia. All the patients were treated in the same way in the postoperative period: NSAIDs were given intravenously to adults and rectally to children. Acetaminophen was given intravenously or rectally (children aged < 15 yr) if additional analgesic support was requested by the patient. Additional acetaminophen consumption was recorded daily. Pain scores were assessed on every patient with the use of a visual analogue scale (VAS) at rest, 1, 5, 9, 13, 17, 21 and 36 h after surgery, and also on swallowing during the first postoperative day. RESULTS: Global VAS pain scores were lower in the groups treated with bupivacaine infiltration during the first 24 h after surgery (P < 0.05). Supplementary analgesic consumption was lower in group 3 than in group 2 during the 0-9 h interval immediately following surgery (P < 0.05). There were no statistically significant differences for any other parameters between the 3 groups. CONCLUSION: These results suggest that the timing of peritonsillar infiltration with bupivacaine is not of clinical importance and does not affect the quality of postoperative analgesia in patients undergoing tonsillectomy.

Adolescent↗
PubMed1995

[Effects of midazolam on respiratory drive in healthy volunteers].

OBJECTIVE: To compare the effects of a sedative dose of midazolam on mean inspiratory flow (VT/TI = index of central respiratory activity), known as being decreased by midazolam and the intercostal muscle activity, known as being increased by this agent. STUDY DESIGN: Laboratory study. PATIENTS: Seven healthy volunteers. METHODS: After assessment of baseline values of ventilatory variables and intercostal electromyographic activity (in arbitrary units), midazolam 0.1 mg.kg-1 was administered by iv route. The measurements were repeated after 5 and 10 min, and finally 2 min after the i.v. injection of flumazenil 1 mg. RESULTS: Midazolam decreased VE and VT. Similarly VT/TI ratio decreased from 0.44 +/- 0.04 (baseline value) to 0.26 +/- 0.03 (5 min) and 0.3 +/- 0.03 L.s-1 (10 min later) respectively (P < 0.05). Conversely, midazolam increased the intercostal electromyographic activity from 4.0 +/- 0.7 (baseline value) to 26.5 +/- 16.6 (5 min) and 28.4 +/- 16.6 U (10 min later) respectively (P < 0.05). Within 2 min after flumazenil administration all variables returned to baseline values. CONCLUSIONS: The decrease of VT/TI ratio is probably linked to increased resistances in the upper airways. This ratio cannot act as an indicator of respiratory drive during sedation or anaesthesia. The assessment of the ventilatory effects of benzodiazepines must be based simultaneously of the various other indicators of the ventilatory drive, as these agents act on the different stages of the ventilatory cycle and therefore cannot be characterized by a unique variable.

Adjuvants, Anesthesia↗
PubMed1994

Effects of halothane on surfactant biosynthesis by rat alveolar type II cells in primary culture.

BACKGROUND: Pulmonary surfactant, which is synthesized by alveolar type II cells (ATII cells) almost exclusively, plays a major role in maintaining alveolar homeostasis by reducing surface tension at the fluid-gas interface. Phosphatidylcholine (PC), the main surfactant lipid component, is largely responsible for this surface activity. The effects of halothane on the phospholipid metabolism of the pulmonary surfactant by ATII cells are unknown, even though these cells are exposed directly to volatile anesthetics during anesthesia and even though any alteration in surfactant biosynthesis by anesthetics may have deleterious effects on lung function and thereby facilitate postoperative pulmonary complications. In the current study, the effects of halothane exposure on surfactant synthesis by rat ATII cells in primary culture were investigated. METHODS: ATII cells were isolated from adult rat lungs and used for the experiments after 24 h in primary culture. The ability of ATII cells to synthesize surfactant was assessed by the incorporation of radioactive precursors in PC. Cytotoxicity was measured by the rate of lactate dehydrogenase release into the culture medium, and the lactate metabolism was taken as an index of glycolytic metabolism. All metabolic measurements were made after 24 h in primary culture. Effects of various halothane concentrations (1, 2, 4, and 8%) exposure for 4 h were studied, as were the effects of 2% halothane for various durations of exposure (2, 4, 8, and 12 h). The reversibility of halothane effects on PC synthesis was assessed after a 2% halothane exposure for 4 h. PC secretion and adenosine triphosphate cellular content were also measured for 4 h exposure at the various halothane concentrations. RESULTS: During a 4-h exposure, PC synthesis was reduced by 10, 24, 29 and 36% for 1, 2, 4, and 8% halothane respectively when compared with control values. At 2% halothane concentration, the observed decreases in PC synthesis were 12, 24, 31 and 34% for 2, 4, 8, and 12 h exposure, respectively. The inhibitory effect of halothane was completely reversed 2 h after the end of exposure. PC secretion was unaffected by increasing halothane concentrations during a 4-h exposure. Halothane did not produce cell damage except for the longest exposure durations (8 and 12 h) at 2% vapor concentration. Whatever the exposure conditions, lactate production by ATII cells exposed to halothane was greater than production by unexposed cells. CONCLUSIONS: These results indicate that halothane decreases the biosynthesis of pulmonary surfactant by ATII cells in primary culture and alters the high energy phosphate metabolism of these cells.

Adenosine Triphosphate↗