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B Plaud

Publications and source records attributed to B Plaud.

At least 37 records · Page 2Linked to original sources
PubMed1998

Population pharmacokinetic-pharmacodynamic analysis of fluindione in patients.

OBJECTIVE: Fluindione is a vitamin K antagonist with a long half-life. This study was designed to investigate the pharmacokinetics and pharmacodynamics of multiple doses of fluindione in patients. METHODS: In a learning group of 49 patients who began fluindione treatment, blood samples were taken 12, 18, or 24 hours after one, three, and five doses. Concentration of fluindione, activity of clotting factors II, VII, IX and X, prothrombin complex activity (PCA), and international normalized ratio (INR) were measured. An indirect-response pharmacodynamic model was used for each effect. A comprehensive analysis was performed with a nonparametric population approach. The model was evaluated in 24 other patients: blood samples were taken 24 hours after two, three, four, and six doses; and PCA and INR were observed. RESULTS: Analysis of concentrations and clotting factor activities showed notably that (1) fluindione has a long half-life (median, 69 hours), and (2) concentration that inhibits the synthesis of the clotting factors by 50% varied for each factor, with a median ranging from 0.25 to 2.05 mg.L-1 for factors VII and II, respectively. The results obtained for INR and PCA were validated in the 24 subsequent patients. CONCLUSION: The population approach allowed the comparison of several pharmacodynamic submodels. This first application of the indirect-response model to multiple oral anticoagulant doses in patients confirmed that both the pharmacokinetics and the pharmacodynamics of fluindione show substantial interindividual variability.

Anticoagulants↗
PubMed1998

[Use of sevoflurane for surgery of pheochromocytoma].

Resection of phaeochromocytoma is associated with sudden changes in arterial pressure. Pharmacodynamic and pharmacokinetic properties of sevoflurane are suitable for maintenance of haemodynamic stability. We report two cases of phaeochromocytoma resection using sevoflurane. Intraoperative hypotensive or hypertensive events have been rapidly controlled, most often only by adjustment of the end-expiratory fraction of sevoflurane.

Adrenal Gland Neoplasms↗
PubMed1998

Resection of liver metastases from a noncolorectal primary: indications and results based on 147 monocentric patients.

BACKGROUND: Very few series have reported indications for and results of hepatectomy for isolated unique or multiple liver metastases (LM) from a noncolorectal primary. We performed a prospective analysis of 147 patients submitted to hepatectomy for LM to evaluate the results and indications for this unusual type of treatment. STUDY DESIGN: Of 538 patients submitted to hepatectomy for a malignant tumor between 1984 and 1996, 147 underwent operations for noncolorectal LM. Conventional and unconventional hepatectomy procedures were used with intermittent clamping of the hepatic pedicle, and in some patients with intermittent vascular occlusion of the liver. RESULTS: Postoperative hospital mortality was 2%. The crude 5-year survival was 36%, and survival without progressive disease was 28%. No difference was observed in survival when synchronous and metachronous LM were compared, or when patients with more or fewer than three LM were compared. Five-year survival rates were 20% for 35 breast cancers, 74% for 27 neuroendocrine tumors, 46% for 20 testicular tumors, 18% for 13 sarcomas, and slightly less than 20% for 11 gastric carcinomas, 10 melanomas, and 7 tumors of the gallbladder, according to the primary. Survival exceeded 20% for 6 gynecologic tumors but was disappointing for head and neck cancers, when the primary was unknown, or when the tumor was truly undifferentiated. CONCLUSIONS: Certain guidelines emerge from this series on the indications and uses of adjuvant chemotherapy. Indications for hepatectomy are relatively straightforward for neuroendocrine, testicular, and renal tumors. Hepatectomy for LM from other primaries appears beneficial in certain sarcomas, breast and gynecologic cancers, and perhaps melanoma, for which selection criteria, unfortunately, remain obscure.

Adolescent↗
PubMed1998

Continuous epidural infusion of ropivacaine for postoperative analgesia after major abdominal surgery: comparative study with i.v. PCA morphine.

We have compared the quality of three regimens of postoperative analgesia (continuous epidural administration of ropivacaine (Ropi. group), epidural ropivacaine and patient-controlled analgesia (PCA) with i.v. morphine (Ropi. + PCA group) and PCA morphine alone (PCA group)) during the first postoperative 24 h in a multicentre, randomized, prospective study. Postoperative analgesia was studied in 130 patients after major abdominal surgery performed under general anaesthesia. The ropivacaine groups received 20 ml of epidural bolus ropivacaine 2 mg ml-1 via the epidural route at the end of surgery, followed by continuous infusion of 10 ml h-1 for 24 h. The Ropi. + PCA group also had access to i.v. PCA morphine 1 mg, with a 5-min lockout. The PCA group received morphine as the sole postoperative pain treatment. The two ropivacaine groups had lower pain scores (P < 0.01) than the PCA group. Morphine consumption was higher in the PCA group (P < 0.05) than in the two ropivacaine groups. The quality of pain relief was rated as good or excellent in 79-85% of patients in the three groups. The percentage of patients without motor block increased between 4 and 24 h from 61% to 89% in the Ropi. group, and from 51% to 71% in the Ropi. + PCA group.

Abdomen↗
PubMed1998

Neuromuscular disorders.

Neuromuscular diseases form an heterogeneous group of illnesses. These diseases are rare and studies concerning their anaesthetic management are difficult. Patients with neuromuscular disease represent a challenge for the anaesthesiologist because of the frequent perioperative complications. Cardiac and respiratory functions are often involved, and the severity of the lesions are difficult to estimate. The possible interactions of different drugs necessitates a good knowledge of the drugs' actions and pathophysiological mechanisms.

Journal Article↗
PubMed1997

Monitoring orbicularis oculi predicts good intubating conditions after vecuronium in children.

PURPOSE: The aim of the study was to compare visual estimation of onset of neuromuscular blockade at both the adductor pollicis (AP) and the orbicularis oculi (OO) in children and to determine if monitoring the OO could predict good intubating conditions during vecuronium-induced neuromuscular blockade. METHODS: Thirty ASAI--II children (1.5-9 yr) were studied. Anaesthesia was induced with 6-8 mg.kg-1 thiopentone. The ulnar nerve at the wrist and the temporal branch of the facial nerve were stimulated every 10 sec using train-of-four (TOF) stimuli. Vecuronium, 0.15 mg.kg-1, was administered as a bolus. The responses at both the OO and the AP were evaluated visually. Patients were randomly divided into two groups. In the AP group (n = 15), the trachea was intubated when the AP was completely blocked. In the OO group (n = 15), intubation was performed when the OO was completely blocked. Intubating conditions were scored on a scale of 1 to 4. RESULTS: All the patients had complete blockade at both the orbicularis oculi and the adductor pollicis. In the two group, time from injection of vecuronium to complete neuromuscular blockade was shorter at the orbicularis oculi than at the adductor pollicis, 1.5 +/- 0.5 min vs 2.3 +/- 0.7 min, respectively, (P < 0.05; mean +/- SD) in the AP group, 1.7 +/- 0.3 min vs 2.3 +/- 0.8 min, respectively in the OO group (P < 0.05). Intubating conditions were excellent in all patient except one, where it was rated as good. They did not differ between groups. CONCLUSION: Following administration of 0.15 mg.kg-1 vecuronium in children, monitoring of the OO can detect good intubating conditions 0.7 min earlier than with monitoring of the AP.

Child↗
PubMed1997

Neuromuscular blockade: is it still useful in the ICU?

Neuromuscular relaxants may be administered to ICU patients for days or weeks. The most frequent indications are facilitation of mechanical ventilation and management of neurosurgical patients after severe head injury. Tachyphylaxis can be observed in ICU patients but the major problem remains the prolonged weakness which can occur after long-term administration of muscle relaxants. The mechanisms are still poorly understood and under investigation. Although neuromuscular monitoring provides guidelines for the administration of muscle relaxants in critically ill patients, it does not prevent the development of a myopathy.

Humans↗
PubMed1996

Mivacurium neuromuscular block at the adductor muscles of the larynx and adductor pollicis in humans.

BACKGROUND: Laryngeal muscles must be paralyzed for tracheal intubation. Time to peak effect (onset time) is shorter and intensity of blockade is less at laryngeal muscles compared with the adductor pollicis. The authors' aim in this study was to determine the neuromuscular effects of mivacurium at the laryngeal adductor muscles and the adductor pollicis. METHODS: In 22 adults, anesthesia was induced and maintained with propofol and alfentanil. The force of contraction of the adductor pollicis was recorded, and the laryngeal response was evaluated by measuring the pressure change in the cuff of a tracheal tube positioned between the vocal cords after train-of-four stimulation. Mivacurium (0.07 mg.kg-1 or 0.14 mg.kg-1) was given intravenously (10s). RESULTS: With 0.07 mg.kg-1 mivacurium, onset time was 151 +/- 40 s(mean +/- SD) at the larynx and 241 +/- 79 s at the adductor pollicis, respectively (P < 0.005). Maximum block was 78 +/- 18% and 95 +/- 8%, respectively (P < 0.002), and time to 90% recovery was 11.1 +/- 2.9 min and 23.3 +/- 7.6 min, respectively (P < 0.001). With 0.14 mg.kg-1 mivacurium, onset time also was more rapid at the vocal cords (137 +/- 20 s) than at the adductor pollicis (201 +/- 59 s, P < 0.01). Maximum block was 90 +/- 7% and 99 +/- 1% (P < 0.005), and time to 90% recovery was 16.4 +/- 4.9 min and 27.4 +/- 7.8 min, respectively (P < 0.01). CONCLUSIONS: With mivacurium, onset and recovery are faster at the laryngeal muscles, but block is less intense than at the adductor pollicis. A dose greater than 0.14 mg.kg-1 mivacurium is necessary to ensure complete relaxation at the vocal cords.

Adult↗
PubMed1995

Pharmacokinetics and pharmacodynamics of rocuronium at the vocal cords and the adductor pollicis in humans.

The pharmacokinetic-pharmacodynamic relationship of rocuronium at the laryngeal adductor muscles and the adductor pollicis was determined in eight patients during general anesthesia. Rocuronium was administered as an infusion at a rate of 100 micrograms.kg-1.min-1 over 5 minutes. The half-life of transport between plasma and biophase (effect compartment) was significantly shorter at the adductor laryngeal muscles (2.7 +/- 0.6 minutes, mean +/- SD) than at the adductor pollicis (4.4 +/- 1.5 minutes, p = 0.003). The concentration in the effect compartment producing 50% of the maximum effect was significantly greater at the adductor laryngeal muscles (1424 +/- 148 micrograms.L-1) than at the adductor pollicis (823 +/- 157 micrograms.L-1, p = 0.0001). The shorter onset of neuromuscular blockade at the laryngeal muscles than at the adductor pollicis may be explained by a faster transfer rate at the laryngeal adductor muscles neuromuscular junction than at the adductor pollicis neuromuscular junction.

Adult↗
PubMed1995

Is simultaneous hepatectomy and intestinal anastomosis safe?

BACKGROUND: To assess the safety of simultaneous, "one-stage," hepatectomy and intestinal anastomosis, we retrospectively studied 53 patients who underwent such a procedure, with 76 digestive tract sutures. They represented 80% of all the cases eligible for one-stage procedures among 332 liver resections for malignant tumors. METHODS: The medical records of the patients were retrospectively analyzed to assess details of the surgical procedures, postoperative mortality and morbidity, and postoperative liver function, with special attention being paid to the prothrombin time and the bilirubin value on days 1, 2, 3, and 7. RESULTS: No postoperative mortality occurred and the postoperative morbidity rate was 19%. Only 2 cases of digestive tract anastomotic leakage occurred, which led to reoperation. Hepatectomy-related complications were noted in 5 patients (3 biliary fistulas, 1 hemorrhage and 1 transient liver failure), and pulmonary infections occurred 3 times. The technical difficulties of the one-stage procedure are discussed, focusing on the choice of the incision, the risk of sepsis for the liver if there is an intestinal aperture, possible repercussions of liver impairment and hepatic pedicle clamping on bowel suture healing, and the risk of digestive fistula according to the location of the bowel suture. CONCLUSION: It appears that this one-stage procedure is safe if the bowel is systematically cleaned before the operation, if an appropriate Rio-Branco incision is used, and if the risk of postoperative liver failure is low. It seems preferable to use intermittent hepatic pedicle clamping rather than continuous clamping (when feasible), and to temporarily protect a low rectal anastomosis with a colostomy.

Adult↗
PubMed1994

Neuromuscular effects of vecuronium and neostigmine in Montreal and Paris.

The potency of vecuronium was reported to be greater in Montréal than in Paris. This study was designed to determine whether there were differences in onset, duration, and reversibility with neostigmine between both centres. Twenty ASA I or II adults (ten men, ten women), aged 18-65 yr were studied in each of the two cities, during a standard thiopentone-fentanyl-nitrous oxide (60-70%) - isoflurane 0.5% end-tidal anaesthetic. Train-of-four stimulation was applied every 20 sec to the ulnar nerve at the wrist and the force of contraction of the adductor pollicis muscle was measured. Vecuronium, 0.1 mg.kg-1, was given as a bolus, and neostigmine, 0.04 mg.kg-1, was administered, with atropine 0.02 mg.kg-1, at 25% first twitch height recovery. Onset time to maximum blockade was (mean +/- SD) 3.9 +/- 1.3 min in Paris vs 4.5 +/- 1.3 min in Montréal (NS). Duration from injection to 25% first twitch recovery was shorter (28.5 +/- 6.8 min) in Paris than in Montréal (39.1 +/- 7.3 min) (P < 0.0001). Time from injection of neostigmine to a train-of-four ratio of 70% was not different in Paris (6.3 +/- 2.2 min) from Montréal (5.6 +/- 1.9 min). It is concluded that the duration of an "intubating" dose of vecuronium is longer in Montréal, but, when given at 25% first twitch recovery, neostigmine has the same efficacy in Montréal as in Paris.

Adolescent↗
PubMed1993

Complications and fiberoptic assessment of size 1 laryngeal mask airway.

In pediatric practice, complications due to the laryngeal mask airway (LMA) have been studied with size 2 LMA, but not with size 1 LMA. We, therefore, compared prospectively the complications induced by LMA size 1 and 2 in 141 children aged 21 days to 11 yr. Intraoperative and lowest SpO2 values after removal of LMA were recorded. The following complications were recorded: cough, laryngospasm, bronchospasm, apnea, and airway obstruction. In 14 patients in the size 1 LMA group and 26 patients in the size 2 LMA group, pharyngolaryngeal structures were checked with fiberoptic examination. The number of attempts, complications, intraoperative SpO2, and lowest SpO2 values were similar when using size 1 and size 2 LMA. Fiberoptic examination of size 1 LMA showed a high incidence of impinging of the epiglottis in the LMA bars without airway obstruction. In conclusion, there was no difference in the complication rate between the two pediatric sizes of LMA when used in pediatric patients.

Airway Obstruction↗
PubMed1992

Rocuronium (ORG 9426) neuromuscular blockade at the adductor muscles of the larynx and adductor pollicis in humans.

The effects of rocuronium, 0.25 or 0.5 mg.kg-1, were measured simultaneously on the adductor muscles of the larynx and adductor pollicis in 14 adult patients. Anaesthesia was induced and maintained with propofol and fentanyl. Tracheal intubation was performed without muscle relaxants. The recurrent laryngeal and ulnar nerves were both stimulated supramaximally, at the notch of the thyroid cartilage and at the wrist respectively, using train-of-four stimulation. The laryngeal response was evaluated by measuring the pressure change in the cuff of a tracheal tube positioned between the vocal cords. Onset time, intensity of blockade and duration of action were less at the larynx than at the adductor pollicis. After rocuronium, 0.25 mg.kg-1, the onset time (interval between injection and maximal T1 blockade) was 1.6 +/- 0.1 min and 3.0 +/- 0.3 min (mean +/- SEM) at the laryngeal muscles and adductor pollicis, respectively (P less than 0.01 between muscles). Maximum blockade was 37 +/- 8% and 69 +/- 8%, respectively (P less than 0.05), and time to 90% T1 recovery was 7 +/- 1 min and 20 +/- 4 min, respectively (P less than 0.05). With 0.5 mg.kg-1, the onset time was also more rapid at the vocal cords (1.4 +/- 0.1 min) than at the adductor pollicis (2.4 +/- 0.2 min, P less than 0.001). Maximum blockade was 77 +/- 5% and 98 +/- 1%, respectively (P less than 0.01), and time to 90% T1 recovery was 22 +/- 3 min and 37 +/- 4 min, respectively (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

A method to measure elicited contraction of laryngeal adductor muscles during anesthesia.

The recurrent laryngeal nerve was stimulated with surface electrodes to produce vocal cord adduction, and the response was measured as pressure changes in the inflatable cuff of a tracheal tube positioned between the vocal cords. To test the linearity of the system, a model of the larynx consisting of a syringe barrel was constructed, and weights were applied to two bands of tissue simulating the vocal cords. Tests on Mallinckrodt size-7.5 tubes showed that the pressure increase produced by a given force was independent of baseline pressure in the range 10-30 mmHg. In addition, the pressure inside the inflatable cuff was linear with increasing weight (or force) for a baseline pressure of 10 mmHg. Thirty ASA physical status 1 or 2 adults were anesthetized with propofol and fentanyl. Tracheal intubation was performed in the absence of muscle relaxants, and the inflatable cuff of the tracheal tube was positioned between the vocal cords. Pressure inside the cuff was measured with an air-filled transducer. Stimulation was produced at different sites along the course of the recurrent laryngeal nerve. A surface electrode placed over the notch of the thyroid cartilage produced consistent adduction of the cords, measured as an increase of 8.9 +/- 5.1 mmHg (mean +/- standard deviation [SD]) in the cuff pressure. Neuromuscular blocking drugs produced train-of-four fade, and large doses abolished the response completely, ruling out direct muscle stimulation. It is concluded that this assembly can provide useful information on intrinsic laryngeal muscle function.

Anesthesia↗
PubMed1991

Vecuronium neuromuscular blockade at the adductor muscles of the larynx and adductor pollicis.

The differences between neuromuscular blockade of the adductor muscles of the vocal cords and the adductor pollicis were examined in 20 adult women anesthetized with fentanyl and propofol. Vecuronium 0.04 or 0.07 mg/kg was given as a single bolus by random allocation. The force of contraction of the adductor pollicis was recorded. Laryngeal response was measured as pressure changes in the cuff of the tracheal tube positioned between the vocal cords. Train-of-four stimulation was applied to the recurrent laryngeal nerve at the notch of the thyroid cartilage and to the ulnar nerve at the wrist. Neuromuscular blockade had a faster onset, was less intense, and recovered more rapidly at the vocal cords. With 0.04 mg/kg, maximum blockade of first twitch (T1) was 55 +/- 8 (mean +/- standard error of the mean [SEM]) and 88 +/- 4% at the vocal cords and the adductor pollicis, respectively (P = 0.006). Onset time was 3.3 +/- 0.1 and 5.7 +/- 0.2 min, respectively (P = 0.000001), and time to 90% T1 recovery was 11.3 +/- 1.6 and 26.1 +/- 1.8 min, respectively (P = 0.001). With 0.07 mg/kg, onset time was unchanged; maximum blockade was more intense, being 88 +/- 4 and 98 +/- 1%, respectively (P = 0.04 between muscles); and time to 90% T1 recovery was 23.3 +/- 1.8 min at the vocal cords versus 40.3 +/- 2.9 min at the adductor pollicis (P = 0.001). Approximately 1.73 times as much vecuronium was required at the larynx compared with the dose required at the adductor pollicis for the same intensity of blockade.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMed1991

Neuromuscular effects of succinylcholine on the vocal cords and adductor pollicis muscles.

To quantify the effects of succinylcholine at the laryngeal adductor muscles and the adductor pollicis, 17 adult patients were studied during propofol-fentanyl anesthesia. Train-of-four stimulation was applied to the ulnar nerve at the wrist and the recurrent laryngeal nerve at the notch of the thyroid cartilage. Laryngeal response was measured as pressure changes in the cuff of the tracheal tube positioned between the vocal cords. The force of contraction of the laryngeal adductor muscles and of the adductor pollicis were compared after administration of 0.25 or 0.5 mg/kg of succinylcholine. With 0.25 mg/kg, maximum blockade of first twitch (T1) was 66% +/- 10% (mean +/- SEM) and 45% +/- 13% at the vocal cords and the adductor pollicis, respectively (P less than 0.01). After 0.5 mg/kg, maximum blockade at the vocal cords (93% +/- 2%) and the adductor pollicis (84% +/- 6%) did not differ significantly. For both doses, time to maximal blockade was shorter for the vocal cords (0.9 +/- 0.1 min) than for the adductor pollicis (1.7 +/- 0.2 min; P less than 0.01). Time to 90% recovery of T1 after a bolus of 0.5 mg/kg was similar at the vocal cords (4.3 +/- 0.5 min) and the adductor pollicis (5.2 +/- 0.8 min) (NS). The ED50 was less at the laryngeal adductors (0.170 mg/kg) than at the adductor pollicis (0.278 mg/kg). It is concluded that, in adults, succinylcholine-induced blockade is more rapid and more intense at the laryngeal muscles than at the adductor pollicis.

Adolescent↗
PubMed1990

Vecuronium neuromuscular blockade at the diaphragm, the orbicularis oculi, and adductor pollicis muscles.

To determine the relationship among diaphragm, orbicularis oculi, and adductor pollicis blockade, train-of-four stimulation was applied to the phrenic, facial, and ulnar nerves in 16 adult patients anesthetized with alfentanil-propofol-oxygen. Vecuronium 0.04 or 0.07 mg/kg was given. The response of the adductor pollicis was measured with a force transducer, and that of the other muscles by electromyography (EMG). No statistically significant differences were detected with either dose in the intensity of maximum blockade measured at the three muscles. With 0.04 mg/kg, the first response (T1) in the train-of-four was decreased (mean +/- SEM) 78 +/- 8, 62 +/- 11, and 84 +/- 3% for the diaphragm, orbicularis oculi, and adductor pollicis, respectively. Corresponding values after 0.07 mg/kg were 95 +/- 3, 82 +/- 11, and 95 +/- 2%, respectively. However, onset time was longer at the adductor pollicis than at the diaphragm, and the orbicularis oculi onset time approached that of the diaphragm. With 0.04 mg/kg, time to maximum diaphragmatic blockade was 2.9 +/- 0.3 min, compared with 3.7 +/- 0.6 min at the orbicularis oculi (no significant difference [NS]) and 6.6 +/- 0.4 min at the adductor pollicis (P less than 0.001). With vecuronium 0.07 mg/kg the values were 2.2 +/- 0.3, 3.4 +/- 0.5 (P = 0.024), and 6.3 +/- 0.6 (P less than 0.001), respectively. Time to 75% T1 recovery was similar at the diaphragm and the orbicularis oculi, but significantly longer at the adductor pollicis.(ABSTRACT TRUNCATED AT 250 WORDS)

Diaphragm↗