Persistent left superior vena cava diagnosed by transesophageal echocardiography.
Explore the source record for details and available documents.
Aged↗
Biomedical subjects
F Bonnet
Publications and source records attributed to F Bonnet.
[Temporary relief from pain in the phantom limb after spinal anesthesia using a combination of bupivacaine and clonidine].
Two cases are reported of patients with phantom limb pain after lower limb amputation and requiring surgery of their stump. The stumps were revised and the remaining femoral shaft shortened. Both had spinal anaesthesia for this procedure, with an association of bupivacaine and 150 micrograms of clonidine. In one patient, the phantom pain did not resume for one month, and in the other for three days. The return of pain was preceded by the sensation of a phantom limb. These cases suggest that alpha 2 adrenergic agonists could play a major part in the treatment of phantom limb pain.
Aged↗
[Contribution of transesophageal echocardiography in intensive care: a prospective assessment].
The benefits of transoesophageal echocardiography (TOE) were assessed prospectively in intensive care patients. The doctors carrying out TOE were not the same as those who ordered it. TOE was performed in 32 patients, all of whom but one were intubated and artificially ventilated, to elucidate the cause of circulatory shock, or to search for valvular vegetations or an intracardiac mass. TOE confirmed the diagnosis previously obtained with pulmonary arterial catheterization (10 patients), transthoracic echocardiography (3 patients) or ventriculography (1 patient) in 54% of cases. In 28% of cases, TOE invalidated the suspected diagnosis, and, in the remaining 28% of patients, TOE invalidated provided a previously unsuspected diagnosis. TOE was particularly useful in confirming the presence of valvular vegetations, endocarditis, or intracardiac thrombi, and to assess left ventricular function and preload in patients in shock. Like others, this study confirms the benefits of TOE in the intensive care setting.
Adult↗
Expression of MDR1/P glycoprotein in human sarcomas.
Conflicting reports of MDR1 gene expression in human tumours are observed according to whether studies are performed at the mRNA or P-glycoprotein level. We have investigated this expression in 22 clinically drug-resistant sarcomas at the mRNA level by Northern blot (NB), Dot blot (DB), in situ hybridisation (ISH), and at the protein level by immunohistochemistry (IHC) using three monoclonal antibodies (MoAbs): C219, JSB1, MRK16. Increased MDR1 mRNA expression was detected by NB, DB, and ISH in 1/22 sarcoma (an Ewing's sarcoma). ISH was perfectly correlated with DB hybridisation and confirmed the expression of tumoral cells alone. Specific staining of 100% of tumoral cells was obtained with the three MoAbs in the same sarcoma. Expression in tumoral cells of 12 other sarcomas was detected with MRK16, and positive staining of stromal cells with both C219 (1/22) and MRK16 (8/22) was observed. This study confirms that MDR1 overexpression occurs in human sarcomas but is not the principal mechanism of drug-resistance. Furthermore, positivity with one antibody does not necessarily imply the presence of P glycoprotein (P-gp) and a disparity may exist between the levels of P-gp and its mRNA in the same sample. So care must be taken in interpreting results and more sensitive techniques such as the polymerase chain reaction (PCR) could prove useful.
ATP Binding Cassette Transporter, Subfamily B, Mem↗
Partial reversal of the effects of extradural clonidine by oral yohimbine in postoperative patients.
Extradural clonidine produces analgesia, with sedation, hypotension and bradycardia, in postoperative patients. This study assessed if oral yohimbine would reverse these side effects. We studied 30 ASA I-II patients undergoing orthopaedic surgery. After operation they were allocated randomly to three groups to receive placebo, extradural clonidine 450 micrograms or extradural clonidine 450 micrograms plus oral yohimbine 16 mg. Pain score was measured on a visual analogue scale (VAS); sedation was assessed on a simple scale graded from 0 (awake and alert) to 3 (deeply sedated, awakening after tactile stimulations) and heart rate and arterial pressure were monitored for 5 h. Yohimbine reversed the sedation induced by extradural clonidine, but also shortened the duration of analgesia (31 (SD 15) min, 186 (72) min and 126 (52) min in the placebo, extradural clonidine and extradural clonidine+yohimbine groups, respectively) (P < 0.05), and did not reduce the hypotension and bradycardia related to clonidine administration. These results suggest that alpha 2 adrenoceptors are mediators of the sedation induced by clonidine and that the haemodynamic effects are not related to stimulation of supraspinal alpha 2 receptors.
Administration, Oral↗
Clonidine comparably decreases the thermoregulatory thresholds for vasoconstriction and shivering in humans.
BACKGROUND: Clonidine stops postoperative shivering, but its underlying mechanism of action is unknown. Clonidine may impair central control of thermoregulation or act on peripheral receptors. Accordingly, the authors tested the hypothesis that clonidine reduces both the vasoconstriction and shivering thresholds, a pattern consistent with central thermoregulatory impairment. METHODS: Seven healthy volunteers participated in the study. Thermoregulatory vasoconstriction was evaluated using forearm minus fingertip, skin-temperature gradients; values exceeding 4 degrees C were considered to be significant vasoconstriction. Systemic oxygen consumption (VO2) was measured with a canopy system. In addition, shivering was qualitatively evaluated using a simple scale, graduated from 0 (no shivering) to 2 (intense shivering). The tympanic membrane temperatures triggering significant vasoconstriction and grade 1 shivering were considered to be the thresholds for the two thermoregulatory responses. Measurements were performed after a 10-min steady state period and during cooling by central venous infusion of Ringer's lactate solution at 4 degrees C. Each subject was evaluated at two sessions, separated by at least 48 h. They were randomly and blindly assigned to received either an intravenous bolus of 75 micrograms clonidine or a placebo before cooling. When the shivering score equaled 2, 75 micrograms clonidine was injected intravenously, and repeated if necessary, to completely stop shivering.
Adult↗
Clonidine and ketanserin both are effective treatment for postanesthetic shivering.
BACKGROUND: Although meperidine is an effective treatment of postanesthetic shivering, its mechanism of action remains unknown. Investigation of other drugs might help clarify the mechanisms by which shivering can be controlled. Accordingly, we investigated the efficacy of clonidine, an alpha 2-adrenergic agonist, and ketanserin, a 5-hydroxytryptamine antagonist, in treating postanesthetic shivering. METHODS: First, 54 patients shivering after general anesthesia were allocated randomly to receive an intravenous bolus of saline, 150 micrograms clonidine, or 10 mg ketanserin. A second study explored the dose-dependence of clonidine. Forty shivering patients were given saline or clonidine, 37.5, 75, or 150 micrograms. RESULTS: The duration of shivering was significantly shorter in those given clonidine (2.1 +/- 0.9 min) than in the other two groups and shorter in the ketanserin group (4.3 +/- 0.9 min) than in the saline group (12.0 +/- 1.6 min). Clonidine and ketanserin significantly decreased systolic arterial blood pressure when compared to saline. Core rewarming was significantly slower in the clonidine group. In the second study, 37.5 micrograms clonidine was no more effective than saline. Two minutes after treatment, 150 micrograms obliterated shivering in all patients. Five minutes after treatment, all patients given 75 micrograms had stopped shivering. Systolic arterial pressure and heart rate decreased significantly in patients given 75 and 150 micrograms clonidine. CONCLUSIONS: Clonidine (150 micrograms) and ketanserin (10 mg) both are effective treatment for postanesthetic shivering. The effect of clonidine on shivering is dose-dependent: whereas 37.5 micrograms had no effect, 75 micrograms clonidine stopped shivering within 5 min.
Adult↗
Tumor necrosis factor alpha in human kidney transplant rejection--analysis by in situ hybridization.
Macrophagic infiltration and necrosis of rejected kidney transplants represent two pejorative patterns. It has been assumed that the macrophagic toxicity is mediated partly by secretion of tumor necrosis factor alpha. On the other hand, TNF is also involved in many inflammatory and immunological phenomena. We thus evaluated the expression of TNF mRNA by in situ hybridization in 6 rejected kidney transplants using a radiolabeled TNF-c DNA probe. Then the synthesis of TNF alpha protein was studied by immunohistochemistry using an anti-TNF alpha antibody. In severely rejected kidney grafts, TNF mRNA is expressed in some monomorphic infiltrating cells, mostly located in the deepest part of the cortex and around the tubes. These cells do not bind other probes, such as dopa-decarboxylase DNA or preproenkephalin RNA. They are also recognized by a monoclonal antibody directed against TNF alpha. What is more, this antibody binds with some glomerular endothelial and tubular epithelial cells that do not express TNF mRNA. These cells are likely target cells for TNF. In the normal kidney, there are no cells expressing TNF-alpha mRNA.
Gene Expression↗
DNA relatedness between field isolates of Mycoplasma F38 group, the agent of contagious caprine pleuropneumonia, and strains of Mycoplasma capricolum.
DNA-DNA hybridization experiments were carried out in order to clarify the taxonomic relationships between the F38 group of caprine mycoplasmas, the established etiologic agents of classical contagious caprine pleuropneumonia, and Mycoplasma capricolum, an organism associated with septicemia, arthritis, and mastitis in goats and sheep. The taxonomic status of the F38 group has been uncertain, principally because of the serological, genomic, and other properties which it shares with M. capricolum. Tritium-labeled DNAs from the M. capricolum type strain (California kid) and from prototype strain F38 were hybridized with unlabeled DNAs from these two strains and from four other isolates belonging to each group. The results showed consistent DNA relatedness values of about 70% between the F38 and M. capricolum groups, compared with levels of relatedness of about 90 and 85%, respectively, for the strains within each group. In addition, the results of comparisons of these 10 strains in which growth inhibition and immunofluorescence tests were used confirmed the previously reported serological relationships between the two groups and reinforced other observations concerning their shared genomic and cell membrane characteristics, indicating that there is a close taxonomic relationship. However, as the 70% DNA relatedness values between the M. capricolum and F38 groups also indicate a degree of genomic difference inconsistent with a relationship at the species level, we conclude that our findings support previous proposals for classification of the F38 group as a subspecies of M. capricolum.(ABSTRACT TRUNCATED AT 250 WORDS)
Animals↗
[Is there an advantage to using opioid combinations by the peridural route?].
Epidural opioids provide a potent analgesia not devoided of side effects. In addition, epidural administration of lipid soluble opioids has no clear advantage over the IV route. Combination of epidural opioids with other analgesics may strengthen analgesia and may decrease the incidence of side effects because of a reduction in the amount of opioid administered. Improvement in analgesia quality is documented when local anaesthetics are associated to opioids. Low concentrations of local anaesthetics may potentiate the effect of opioids on ions membrane channels at the level of the dorsal horn of the spinal cord. Alpha adrenergic agonists provide an alternative to local anaesthetics, allowing to improve pain control achieved with opioids. Epinephrine decreases plasma absorption of opioids and is especially useful to prolong the effect of short acting lipid soluble opioids. Alpha adrenergic agonists atc on alpha-2-adrenergic receptors of the spinal cord dorsal horn to depress pain nociceptive transmission. This effect potentiates the one of opioids at this level. Clonidine, which is a selective alpha-2-adrenergic agonist has been demonstrated to improve and to prolong analgesia produced by opioids in postoperative patients. Clonidine administration induces side effects, like sedation, bradycardia and hypotension, but allows to highly reduce the opioid dose. None of the combined techniques of analgesia implies that monitoring of the side effects of opioids has to be reduced.
Adrenergic alpha-Agonists↗
[Value of biological glue in CO2 laser conization. Experience with 32 cases].
The effects of the use of biological glue in the crater that is left after CO2 laser conisation was studied in a series of 32 cases and compared with a previous study carried out using the same technical methods by the same surgeons. The use of biological glue has as its aim to improve capillary haemostasis after conisation; and so increasing the security of leaving these conisation craters in order to improve the chance of normal morphology later. Biological glue has furthermore never given a febrile reaction, nor has it ever increased the likelihood of scar stenosis. Biological glue however is just an extra method of helping normal morphological healing with a good transformation zone and retaining fertility. When conisation is carried most extensively (in particular as far as depth is concerned) and with the use of powerful laser beams, the application of biological glue seem to guarantee most forms of postoperative haemostasis and good healing.
Adult↗
[Shoulder surgery using a plexus block: for or against. Against].
Brachial plexus block is an alternative and elegant procedure for shoulder surgery. Three main concerns have to be considered when this technique is planed. Firstly, large amounts of local anaesthetic solution are necessary to achieve complete blockade of the region especially when the deeper tissues of the shoulder are concerned by the procedure. Secondly interscalenic cervical plexus block produces homolateral phrenic paralysis and may impair respiratory function in patients at risk or when supplemental IV drugs are administered. Thirdly, when nerve lesions of different mechanisms including plexus block itself occur, the origin of the lesion may be difficulty related to its cause. Indications of cervical block are therefore to be considered cautiously when shoulder surgery is performed.
Brachial Plexus↗
Usefulness of consensus conferences: the case of albumin.
The usefulness of consensus conferences has been questioned. We have assessed the impact of a 1989 consensus conference about the treatment of hypovolaemia on prescribing practice at our hospital. Data available from the blood bank enabled us to follow albumin use and costs by department between 1987 and 1991. Medical journals, direct mail, and meetings were used to disseminate the recommendations of the consensus conference, which were that the only indications for albumin are massive haemorrhage, plasmapheresis, massive hypoalbuminaemia, and volume expansion in pregnancy; for hypovolaemia caused by septic shock or vasoplegia, fluid gelatins and crystalloids should be used. In the year after the conference, and in subsequent years, albumin use and costs were 40% lower than before the conference, even though total medical expenditure continued to rise and numbers of patients admitted did not change. We believe that consensus conferences can be a useful means of improving medical practice. The features that ensured success in this programme were the small number of prescribers, the homogeneous setting, and the frequent restatement of the recommendations.
Consensus Statements as Topic↗
Characterization of a human seminal plasma glycosaminoglycan-bearing polypeptide.
A glycosaminoglycan-bearing polypeptide (S.GP), present in human seminal plasma, was purified to homogeneity by a combination of CsCl density-gradient centrifugation, f.p.l.c. ion-exchange chromatography on a Mono Q HR column and Superose 6 gel filtration. The observed polydispersity of S.GP was attributed to the heterogeneity of its glycosaminoglycan content. Enzymic deglycosylation experiments and N-terminal amino-acid sequence determination indicate that it consists of a polypeptide (apparent molecular mass approx. 18 kDa) bearing both chondroitin and heparan sulphate chains. Evidence is given that S.GP contains a glycosaminoglycan-linkage domain of a so far uncharacterized gene product, proteolytically processed in the genital tract.
Amino Acid Sequence↗
Test of 20 similar intensive care ventilators in daily use conditions--evaluation of accuracy and performances.
Infrequent control, aging of components, may compromise the accuracy of ICU ventilators. In order to assess the reliability of ventilators during their clinical use, we bench tested a group of 20 CPU1 ventilators (Ohmeda) sampled at random in several ICU units. We found major leaks in 5 ventilators, attributable to the disposable tubings used in these systems. Mean error in expired tidal volume and corresponding standard deviation (precision) were greater than 100 ml in two. Positive end expiratory pressure measurement comprised a mean error higher than 2 cm H2O in 40% of the ventilators tested. The valve opening pressure threshold was correlated to the inspiratory flow (r = 0.81) contrary to the valve opening delay (average 138 +/- 40 ms). These two parameters did not correlate with the age of the ventilator. Our study addresses the need for periodic control of ventilator performance in order to minimize the risks of errors and malfunctions.
Age Factors↗
Clinical and pharmacokinetic aspects of the combination of meperidine and prilocaine for spinal anaesthesia.
The aim of this study was to determine whether the addition of a small dose of prilocaine could augment the spinal block induced by meperidine and affect intrathecal meperidine pharmacokinetic behaviour. Spinal anaesthesia was performed in 60 men scheduled for endoscopic resection of a prostatic adenoma or bladder tumour under spinal anaesthesia. They were allocated randomly to receive either 1 mg.kg-1 meperidine (Group 1, n = 30), or 1 mg.kg-1 meperidine plus 0.5 mg.kg-1 prilocaine (Group 2, n = 30). Blood samples were collected prior to and for 24 hr after spinal injection in 24 patients (12 in each group). Plasma meperidine levels were assayed by gas chromatography. Complete motor block was achieved in all Group 2 patients, but was incomplete in seven of Group 1 (P less than 0.05). The onset of both motor and sensory blocks was shorter (P less than 0.01) in Group 2 and the duration was longer (P less than 0.05). Coadministration of prilocaine modifies meperidine pharmacokinetic behaviour. The area under curve was 48% greater (P less than 0.01) and Cmax was higher in Group 2 than in Group 1, 145.8 +/- 42.2 vs 107 +/- 20.5 ng.ml-1 (P less than 0.001). No evidence of respiratory depression was noted in any of the patients. Despite the increase in plasma meperidine concentrations, no side effects were observed. The plasma concentrations remained at one third to one sixth the levels reported to induce a respiratory depression. It is concluded that the addition of prilocaine to meperidine improves motor and sensory block during surgery and alters meperidine kinetics without producing major side effects.
Aged↗
[Patient-controlled analgesia: effect of adding continuous infusion of morphine].
This double blind study aimed to assess the effects of a continuous intravenous (i.v.) infusion of morphine added to an intermittent bolus patient controlled analgesia on morphine demand and related side-effects. Patients scheduled for abdominal and thoracic surgery (ASA 2 or 3) were randomly allocated postoperatively to three groups (n = 10 each): group 1 were given i.v. boluses of 2 mg of morphine (lockout interval = 15 min); the other two groups were given the same boluses as well as a continuous i.v. infusion of either 1 mg.kg-1 of morphine (group 2) or 2 mg.kg-1 (group 3). Pain was assessed with a visual analog scale before starting analgesia, and after 1, 2, 3, 4, 8, 16, 24 and 36 h. Total and bolus morphine doses were recorded at the same time. Breathing rate and the level of sedation were measured every hour and blood gases every time 40 mg of morphine had been consumed. Morphine administration was stopped if breathing rate decreased to less than 10 c.min-1, the patient became too sedated, or PaCO2 rose to more than 45 mmHg. Pain scores were similar in the three groups. Total amounts of morphine were higher in groups 2 (56.8 +/- 23.8 mg) and 3 (116.2 +/- 41.8 mg) compared with group 1 (38.2 +/- 17.8 mg) (p < 0.05). Morphine administration was stopped in 5 patients in group 3 and in 1 in group 2 because PaCO2 had risen to more than 45 mmHg. Therefore, a continuous i.v. infusion is not required in patients receiving PCA, all the more so as this has deleterious respiratory effects.
Aged↗
[A study of 11 ventilators for anesthesia: laboratory testing].
Eleven anaesthesia ventilators were instrumentally tested under various conditions. They included: Excel and Modulus II Plus (Ohmeda); 710 and Servo anaesthesia circle 985 (Siemens); Jollytronic (Soxil) and Elsa (Engström); SA2 and Cicero (Dräger); ABT 4,300 (Kontron); Monnal A and the prototype Alys (Taema). The test circuit comprised a two compartment model lung, a pneumotachograph, a pressure gauge in the "airway". The volume was calculated as the integral of flow rate. Each machine was calibrated by the firms' technicians. Before each test, the pneumotachograph was calibrated using a 11 air syringe and the pressure gauge with a 5 cm water column. Each machine ventilated the model lung for 30 min before starting the tests. There were five tests: 1) reliability of the machine's spirometer, 2) reliability of the ventilation rate, 3) reliability of pressure measurements, 4) effect of increasing fresh gas flow on spirometry, 5) effect of increasing downstream resistances. In usual simulated ventilatory conditions, all the machines accurately delivered the setted ventilation and spirometric measurements were with minimal error only. Several ventilators (SA2, Excel, 710, Elsa, ABT 4,300) did not succeed in maintaining their performances when compliance was strongly decreased or resistance of the test lung notably increased. Resistance in the circuit during simulated spontaneous ventilation was < 3.6 cmH2O.l-1.s-1. Increasing fresh gas flow raised the minute volume delivered in six ventilators. It is concluded that, during extreme ventilatory conditions, the inspired volume must be adjusted so as to maintain the inspired tidal volume. However, ventilators which increase inspiratory time in response to an increased mechanical load cannot be adjusted by this way.
Anesthesia, Closed-Circuit↗