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1.
Nature ; 591(7848): 54-60, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33658692

RESUMO

Growing interest in quantum computing for practical applications has led to a surge in the availability of programmable machines for executing quantum algorithms1,2. Present-day photonic quantum computers3-7 have been limited either to non-deterministic operation, low photon numbers and rates, or fixed random gate sequences. Here we introduce a full-stack hardware-software system for executing many-photon quantum circuit operations using integrated nanophotonics: a programmable chip, operating at room temperature and interfaced with a fully automated control system. The system enables remote users to execute quantum algorithms that require up to eight modes of strongly squeezed vacuum initialized as two-mode squeezed states in single temporal modes, a fully general and programmable four-mode interferometer, and photon number-resolving readout on all outputs. Detection of multi-photon events with photon numbers and rates exceeding any previous programmable quantum optical demonstration is made possible by strong squeezing and high sampling rates. We verify the non-classicality of the device output, and use the platform to carry out proof-of-principle demonstrations of three quantum algorithms: Gaussian boson sampling, molecular vibronic spectra and graph similarity8. These demonstrations validate the platform as a launchpad for scaling photonic technologies for quantum information processing.

2.
Phys Rev Lett ; 129(14): 142502, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36240396

RESUMO

The root mean square radii of the proton density distribution in ^{16-24}O derived from measurements of charge changing cross sections with a carbon target at ∼900A MeV together with the matter radii portray thick neutron skin for ^{22-24}O despite ^{22,24}O being doubly magic. Imprints of the shell closures at N=14 and 16 are reflected in local minima of their proton radii that provide evidence for the tensor interaction causing them. The radii agree with ab initio calculations employing the chiral NNLO_{sat} interaction, though skin thickness predictions are challenged. Shell model predictions agree well with the data.


Assuntos
Nêutrons , Prótons , Carbono
3.
Nature ; 486(7403): 341-5, 2012 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-22722192

RESUMO

The shell structure of atomic nuclei is associated with 'magic numbers' and originates in the nearly independent motion of neutrons and protons in a mean potential generated by all nucleons. During ß(+)-decay, a proton transforms into a neutron in a previously not fully occupied orbital, emitting a positron-neutrino pair with either parallel or antiparallel spins, in a Gamow-Teller or Fermi transition, respectively. The transition probability, or strength, of a Gamow-Teller transition depends sensitively on the underlying shell structure and is usually distributed among many states in the neighbouring nucleus. Here we report measurements of the half-life and decay energy for the decay of (100)Sn, the heaviest doubly magic nucleus with equal numbers of protons and neutrons. In the ß-decay of (100)Sn, a large fraction of the strength is observable because of the large decay energy. We determine the largest Gamow-Teller strength so far measured in allowed nuclear ß-decay, establishing the 'superallowed' nature of this Gamow-Teller transition. The large strength and the low-energy states in the daughter nucleus, (100)In, are well reproduced by modern, large-scale shell model calculations.

4.
Phys Rev Lett ; 117(10): 102501, 2016 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-27636470

RESUMO

Proton radii of ^{12-19}C densities derived from first accurate charge changing cross section measurements at 900A MeV with a carbon target are reported. A thick neutron surface evolves from ∼0.5 fm in ^{15}C to ∼1 fm in ^{19}C. The halo radius in ^{19}C is found to be 6.4±0.7 fm as large as ^{11}Li. Ab initio calculations based on chiral nucleon-nucleon and three-nucleon forces reproduce the radii well.

5.
Phys Rev Lett ; 113(13): 132501, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25302882

RESUMO

The first determination of radii of point proton distribution (proton radii) of (12-17)B from charge-changing cross sections (σ(CC)) measurements at the FRS, GSI, Darmstadt is reported. The proton radii are deduced from a finite-range Glauber model analysis of the σ(CC). The radii show an increase from ¹³B to ¹7B and are consistent with predictions from the antisymmetrized molecular dynamics model for the neutron-rich nuclei. The measurements show the existence of a thick neutron surface with neutron-proton radius difference of 0.51(0.11) fm in ¹7B.

6.
Phys Rev Lett ; 109(16): 162502, 2012 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-23215071

RESUMO

The neutron-rich lead isotopes, up to (216)Pb, have been studied for the first time, exploiting the fragmentation of a primary uranium beam at the FRS-RISING setup at GSI. The observed isomeric states exhibit electromagnetic transition strengths which deviate from state-of-the-art shell-model calculations. It is shown that their complete description demands the introduction of effective three-body interactions and two-body transition operators in the conventional neutron valence space beyond (208)Pb.

7.
Folia Biol (Praha) ; 48(4): 154-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12194203

RESUMO

Electroporation represents a powerful technique for cell transfection; however, its efficiency in haemopoietic cells (approximately 1%) is largely unsatisfactory. Biological processes in haemopoietic cells are often studied using leukaemia cell line HL-60. For this reason we developed conditions for efficiently introducing plasmids to HL-60 cells by electroporation, as an alternative to other techniques. This technique employs the electric pulse (250-270 V; 1000 microF) followed by separation of living cells on a Ficoll-Paque discontinuous gradient. Using 10-20 micrograms of plasmid, we routinely achieve 12-14% of transfectants.


Assuntos
Eletroporação , Transfecção , Sobrevivência Celular/fisiologia , Proteínas de Fluorescência Verde , Células HL-60 , Humanos , Proteínas Luminescentes/metabolismo , Plasmídeos/genética , Plasmídeos/metabolismo
8.
Phys Rev E Stat Nonlin Soft Matter Phys ; 84(6 Pt 1): 061125, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22304058

RESUMO

We derive a multiplication law for free non-Hermitian random matrices allowing for an easy reconstruction of the two-dimensional eigenvalue distribution of the product ensemble from the characteristics of the individual ensembles. We define the corresponding non-Hermitian S transform being a natural generalization of the Voiculescu S transform. In addition, we extend the classical Hermitian S transform approach to deal with the situation when the random matrix ensemble factors have vanishing mean including the case when both of them are centered. We use planar diagrammatic techniques to derive these results.

9.
Colloids Surf B Biointerfaces ; 88(1): 63-71, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21764267

RESUMO

The interaction of cells with nanoscale topography has proven to be an important modality in controlling cell responses. Topographic parameters on material surfaces play a role in cell growth. We have synthesized a new bio compatible polymer containing photoswitching molecules. Stripepatterned (groove/ridge pattern) were patterned and erased with ease on this bio azopolymer with two different set-ups: one with the projection of an optical interference pattern and the other one by molecular self-organization with one single laser beam. These two set-ups allow the re-writing of pattern after erasing and its inscription in vitro. PC12 cells were cultured on the bio-photoswitching patterned polymer and compared with PC12 cells growing on a well know substrate: poly-L-lysine. This result is of interest for facilitating contact guidance and designing reconfigurable scaffold for neural network formation in vitro.


Assuntos
Nanoestruturas/química , Polímeros/química , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Microscopia de Força Atômica , Células PC12 , Fotoquímica , Polímeros/farmacologia , Ratos , Propriedades de Superfície
10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 81(4 Pt 1): 041132, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20481702

RESUMO

We show that the eigenvalue density of a product X=X1X2...XM of M independent NxN Gaussian random matrices in the limit N-->infinity is rotationally symmetric in the complex plane and is given by a simple expression rho(z,z)=1/Mpisigma(-2/M)|z|(-2+(2/M)) for |z|sigma. The parameter sigma corresponds to the radius of the circular support and is related to the amplitude of the Gaussian fluctuations. This form of the eigenvalue density is highly universal. It is identical for products of Gaussian Hermitian, non-Hermitian, and real or complex random matrices. It does not change even if the matrices in the product are taken from different Gaussian ensembles. We present a self-contained derivation of this result using a planar diagrammatic technique. Additionally, we conjecture that this distribution also holds for any matrices whose elements are independent centered random variables with a finite variance or even more generally for matrices which fulfill Pastur-Lindeberg's condition. We provide a numerical evidence supporting this conjecture.

12.
Phys Rev Lett ; 102(15): 152501, 2009 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-19518623

RESUMO

The first measurement of the momentum distribution for one-neutron removal from (24)O at 920A MeV performed at GSI, Darmstadt is reported. The observed distribution has a width (FWHM) of 99 +/- 4 MeV/c in the projectile rest frame and a one-neutron removal cross section of 63 +/- 7 mb. The results are well explained with a nearly pure 2s_{1/2} neutron spectroscopic factor of 1.74 +/- 0.19 within the eikonal model. This large s-wave probability shows a spherical shell closure thereby confirming earlier suggestions that (24)O is a new doubly magic nucleus.

13.
Schmerz ; 2(1): 19-25, 1988 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-18415263

RESUMO

Systemic application of analgesics is still the most frequently used method of postoperative relief of pain. However, neither intermittent intramuscular nor intermittent intravenous application can provide the patient with a continuous level of analgesia. Lipid-soluble analgesics or those with polar binding that are rapidly metabolized demonstrate an rapid effectiveness. If the analgesia must be administered over a long period, it is due to a low level of lipid solubility, high receptor affinity and low elimination rates. Oral as well as sublingual buccal and rectal applications are characterized by uncertain absorption conditions. There are few investigations on the subcutaneous application of analgesics. After intramuscular administration analgesic levels are achieved within 15 to 60 min, but various conditions may alter the absorption criteria. Intradeltoidal application is preferable to intragluteal injection. Analgesics may be administered intravenously as a bolus, as continuous infusion, or as patient-controlled analgesia. The bolus injection is characterized by a short period of action and the necessity to administer several bolus injections by repeated administration. The continuous infusion of analgesics should begin with the administration of an initial bolus injection. Infusion analgesia should be performed under careful monitoring conditions. The most promising method of pain relief is patient-controlled analgesia (PCA). After an initial bolus injection, the continuous infusion of an analgesic is guaranteed and may be completed by the patient with several bolus injections. PCA requires careful monitoring. We suggest that a special analgesia team to take care of the patient in special analgesia units might be appropriate in the future.

14.
Anaesthesist ; 41(3): 137-41, 1992 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-1570886

RESUMO

A lack of uniform methodology used by different authors in the assessment of different puncture techniques in spinal anesthesia formed the basis of the current study, which compared under randomized conditions the incidence of post spinal headache after a median or paramedian (lateral) approach. MATERIALS AND METHODS. Two hundred and fifty ASA physical status II and III patients, aged 50-85 years, scheduled for transurethral prostate surgery under spinal anesthesia were investigated. The patients were comparable with regard to weight and height (Table 1). No premedication was given and, 30 min prior to surgery, all patients received normal saline 400-500 ml i.v. The patients were randomly divided into two groups of 125 patients each to receive 4 ml 0.5% bupivacaine in 5% glucose (specific gravity 1.017 at 20 degrees C) using the median or paramedian (lateral) approach according to the following scheme (Table 2): I: 4 ml 0.5% bupivacaine/median approach; II: 4 ml 0.5% bupivacaine/paramedian approach. The study was carried out in a double-blind fashion. Neither the patient nor the investigator evaluating the post spinal headache was aware of which technique had been used. Lumbar puncture was performed by a midline approach at the L3-4 interspace using a 25-gauge (Whitacre) spinal needle with the patient in the sitting position group I. The bevel of the spinal needle was directly laterally, so that the dural fibers that run longitudinally were spread rather than transected. When using the paramedian approach (group II), patients were placed in the flexed lateral decubitus position and the spinal needle inserted 1 cm medial and 1 cm lateral and caudad to the lowest part of the posterior superior iliac spine and then directed medially and cephalad at an angle of 55 degrees into the subarachnoid space. Postoperatively, patients were allowed to move as soon as possible; no prophylactic bed rest was ordered. Starting from the 1st postoperative day, patients were evaluated by an independent observer and asked whether they were suffering from any problems concerning anesthesia. Typical post-puncture headache was defined as invariably bifrontal and occipital, frequently involving the neck and upper shoulders, and being aggravated by the upright position. Statistical analysis of the data was performed using the Mann-Whitney rank-sum test for unpaired samples. A P value of less than 0.05 was considered statistically significant. RESULTS. Twenty-six of 250 patients (10.4%) developed post spinal headaches. Comparing both groups, 11/125 (8.8%) patients in the median group (group I) versus 15/125 (12%) in the paramedian group (group II) had typical post-puncture headaches. Within the group of patients aged 50-60 years, the paramedian approach (group II) showed a significantly higher headache rate compared with group I (P less than 0.05). Neurologic sequelae were not observed; 6 patients received epidural injections of autologous blood while the rest of the patients suffering from post spinal headache were treated conservatively with bed rest, analgesics, and fluids. CONCLUSIONS. The results indicate that the incidence of post spinal headache is higher in younger patients when using the paramedian (lateral) approach. However, our findings suggest that the choice of lumbar puncture technique--median or paramedian--is of little importance in regard to post-puncture headache in elderly patients. The paramedian approach is especially useful when degenerative changes are encountered in the interspinous structures in elderly patients, when an ideal position is difficult to achieve.


Assuntos
Raquianestesia , Cefaleia/etiologia , Punção Espinal/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Alemanha/epidemiologia , Cefaleia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prostatectomia , Punção Espinal/métodos
15.
Anaesthesist ; 38(12): 673-80, 1989 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-2575875

RESUMO

A lack of uniform methodology used in the assessment of moderate doses of sufentanil in combination with non-depolarizing neuromuscular blocking drugs formed the basis of the current study which compared under randomized conditions the effects of sufentanil-pancuronium versus sufentanil-vecuronium on hemodynamics, intubating conditions and chest wall rigidity during induction of anesthesia. MATERIAL and METHODS. One hundred and twenty ASA physical status I and II patients aged between 20 and 40 years of age who were undergoing elective urological surgery were included in the study. Premedication consisted of 0.15 mg kg-1 diazepam, given orally 60 min prior to induction of anesthesia. Patients were randomly divided into eight groups of 15 each to receive 0.5 microgram kg-1 sufentanil or placebo in combination with pancuronium (groups I-IV) or vecuronium (groups V-VIII) Within each group, patients were randomly allocated to receive the relaxant either as a single bolus dose of 0.095 mg kg-1 pancuronium or 0.1 mg kg-1 vecuronium, or in divided doses (the priming principle), the smaller priming dose (0.015 mg kg-1 pancuronium or 0.015 mg kg-1 vecuronium) being administered 2 min before induction of anesthesia with 5 mg kg-1 thiopentone, followed by the second intubating dose of 0.080 mg kg-1 pancuronium or 0.085 mg kg-1 vecuronium. To maintain blind study conditions in the groups, the patients given the relaxants in one dose were given an equivalent volume of saline 2 min prior before 5 mg kg-1 thiopentone. Intubating was attempted 60 s after administration of the main dose of the relaxant, and conditions were assessed on a four-point scale: excellent, satisfactory, fair, or poor. Neuromuscular transmission was monitored with the Datex Relaxograph, a neuromuscular transmission analyzer, that utilizes the integration of the EMG response. Producing train-of-four (TOF) stimuli, with a pulse width of 100 microseconds and a frequency of 2 Hz every 20 s the following parameters were recorded by the Datex Relaxograph: The percentage of first twitch amplitude compared with the reference (T1), and the train-of-four (TOF) ratio, i.e., the ratio of last twitch height to first height. Measurements were taken after premedication in the operating room, the value which served as a baseline (t0), 1 min after sufentanil or placebo (t1), 1 min after priming or placebo (t2), 1 min after thiopentone (t3), and 1 min after intubation (t4).(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Anestésicos/farmacologia , Fentanila/análogos & derivados , Hemodinâmica/efeitos dos fármacos , Intubação Intratraqueal , Pancurônio/farmacologia , Brometo de Vecurônio/farmacologia , Adulto , Combinação de Medicamentos , Fentanila/farmacologia , Humanos , Pessoa de Meia-Idade , Rigidez Muscular/induzido quimicamente , Ensaios Clínicos Controlados Aleatórios como Assunto , Sufentanil , Tórax/efeitos dos fármacos
16.
Anasth Intensivther Notfallmed ; 23(5): 260-4, 1988 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-3149155

RESUMO

Fentanyl and alfentanil may cause bradycardia if used in combination with succinylcholine during induction of anaesthesia. We therefore studied the influence of atropine, fentanyl and alfentanil on the haemodynamics of 90 urological patients (ASA I, II), who were allocated at random to six groups containing 15 patients each. Induction of anaesthesia was carried out using atropine 0.01 mg/kg-1, fentanyl 0.15 mg or alfentanil 1.5 mg depending on the assigned group: I atropine + fentanyl, II: atropine + alfentanil, III: fentanyl, IV: alfentanil, V: control (no atropine, no analgetic), VI: atropine. Following 2 mg alcuronium and thiopentone 4 mg/kg-1 intubation was performed with 2 mg/kg-1 succinylcholine. Atropine in combination with fentanyl caused a significant increase in heart rate following endotracheal intubation (p less than 0.05). Arrhythmias occurred in the groups with atropine in 4 out of 45 cases, while a chest wall rigidity was not influenced by atropine. Bradycardia occurred after fentanyl or alfentanil with atropine in the same frequency as without atropine. According to our results the routine use of atropine for induction of anaesthesia with thiopentone/fentanyl or alfentanil even in combination with succinylcholine is not required in ASA I or II patients.


Assuntos
Anestesia Endotraqueal , Anestésicos , Atropina , Pressão Sanguínea/efeitos dos fármacos , Fentanila/análogos & derivados , Frequência Cardíaca/efeitos dos fármacos , Tono Muscular/efeitos dos fármacos , Adulto , Alfentanil , Arritmias Cardíacas/induzido quimicamente , Humanos , Músculos Peitorais/efeitos dos fármacos , Doenças Urológicas/cirurgia
17.
Reg Anaesth ; 9(4): 110-5, 1986 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-2434976

RESUMO

The effect of Trendelenburg position (5 degrees head-down) for 60 or 45 s on the spread of hyperbaric 0.5% tetracaine and 0.5% bupivacaine (3 or 4 ml) was studied in 80 patients scheduled for urological surgery. The mean spread of analgesia was faster (p less than 0.05) and greater (p less than 0.05) in patients tilted head-down for 45 s receiving 4 ml tetracaine than in those with 3 ml tetracaine and 60 s Trendelenburg position. With bupivacaine corresponding results of both volumes, 3 or 4 ml, were similar. Tetracaine compared with bupivacaine showed a faster cephalad spread with 4 ml (p less than 0.05) but not with 3 ml. The onset time of motor blockade in all groups was short (less than 10 min) and complete (Bromage III). The results prove that 4 ml of 0.5% tetracaine with 5% Trendelenburg position for 45 s ensure a rapid and safe spread of analgesia with adequate motor blockade for transurethral surgery.


Assuntos
Raquianestesia , Bupivacaína , Postura , Hiperplasia Prostática/cirurgia , Tetracaína , Idoso , Relação Dose-Resposta a Droga , Humanos , Masculino , Neurônios Motores/efeitos dos fármacos , Nociceptores/efeitos dos fármacos , Distribuição Aleatória
18.
Reg Anaesth ; 10(3): 82-7, 1987 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-3116609

RESUMO

INTRODUCTION: The effect of different injection temperatures on carbonated anesthetics has been controversial since 1965. The current study was undertaken to determine onset times of sensory and motor blockade after epidural anesthesia with 0.5% bupivacaine-CO2 and 0.5% bupivacaine-HCl at various injection temperatures. MATERIALS AND METHODS: The study was performed on 90 ASA class I-II urologic patients during extracorporeal shock wave lithotripsy. The patients were randomized in six groups to receive either 0.5% bupivacaine-CO2 or 0.5% bupivacaine-HCl at temperatures of 4 degrees, 20 degrees, or 36 degrees C. The six groups were comparable in age, height, and weight. Epidural anesthesia was performed at the L2-3 interspace with an 18-gauge Tuohy needle using loss of resistance. A catheter was advanced 4 cm in the epidural space and 4 ml 0.5% bupivacaine with adrenaline 1:200,000 was given as a test dose. After 4 min the full anesthetic dose, based on body size, was injected with the patient supine. Sensory blockade was determined by the pinprick method and motor blockade by the Bromage method at 2-min intervals for the first 20 min, at 5-min intervals for the next 10 min, and then every 15 min to a total of 240 min. Statistical analysis was done by the Mann-Whitney test, with P less than 0.05 considered significant. RESULTS: Spread of sensory blockade was significantly faster with bupivacaine-CO2 and -HCl at a temperature of 36 degrees C as compared to 4 degrees or 20 degrees C (P less than 0.05) (Figs. 1, 2 and Table 2).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Analgesia , Anestesia Epidural , Anestesia Local , Bupivacaína/administração & dosagem , Dióxido de Carbono/administração & dosagem , Litotripsia , Combinação de Medicamentos , Humanos , Bloqueio Nervoso , Temperatura , Fatores de Tempo
19.
Artigo em Alemão | MEDLINE | ID: mdl-1873422

RESUMO

Thiopentone concentrations in blood following injection of the induction solution (Thiopental, 2.5%) may be critical in the context of lethal complications arising during induction of anaesthesia and thereby the toxicological aspects of this drug can become an issue in forensic considerations. The study was designed to find out whether the dose of injected thiopentone may be calculated from blood levels measured in nine pregnant and ten non-pregnant patients. The doses injected ranged from 4-5 mg per kg body weight. The drug was administered as a single bolus dose to the patients undergoing Caesarean section. In the non-pregnant group the first dose of thiopentone was given over 25 s. After that repeated doses of 50 mg were injected over 2s every 20s until the eyelid reflex was ceased. Blood samples for determination of thiopentone were withdrawn from an indwelling catheter inserted to a large cubital vein in the arm opposite that used for the injection and thiopentone levels were measured from blood after column extraction (Extrelut) using spectrophotometry. Venous peak values were found 40-115s after injection in the Caesarean group (mean: 20.3 micrograms kg-1) and were higher than in the non-pregnant patients (97-190s, mean: 17.8 micrograms kg-1). No correlation was found regarding venous peak levels (mgkg-1 blood) and induction dose (mgkg-1 body weight), neither in the pregnant nor in the non-pregnant group. Our findings would suggest that the injected thiopentone dose cannot be calculated from the concentration of the drug in the blood. Forensic conclusions concerning the onset of lethal complications during the induction of anaesthesia cannot be drawn on the grounds of venous thiopentone concentrations.


Assuntos
Anestesia Intravenosa , Anestesia Obstétrica , Medicina Legal , Tiopental/sangue , Adulto , Feminino , Humanos , Injeções Intravenosas , Gravidez , Tiopental/administração & dosagem
20.
Reg Anesth ; 14(1): 26-30, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2486582

RESUMO

Barbotage is the aspiration of the injected volume back into the syringe followed by reinjection twice, with 0.5 ml increases in each aspirated volume. The effects of this technique versus injection without barbotage, on the spinal anesthetic spread of 0.5% tetracaine or 0.5% bupivacaine in 5% glucose 4 ml each, were investigated in 80 men undergoing urologic surgery. The local anesthetic solutions were randomly injected into four groups of 20 patients each, and the anesthetic profile of each solution was then evaluated in a double-blind fashion for the two techniques (barbotage/without barbotage) by an independent observer. In the tetracaine groups, barbotage was associated with a higher dermatome level and shorter time to reach this compared with tetracaine without barbotage. Barbotage caused the latency of bupivacaine to be shorter, but the actual time difference was small and clinically not relevant. Comparing tetracaine and bupivacaine, tetracaine with barbotage achieved a higher segmental level. Time to highest dermatome, however, was shorter for bupivacaine with barbotage compared with tetracaine with barbotage. Barbotage shortened the onset of 3+ motor block with bupivacaine. This difference was statistically significant. Results suggest that barbotage is useful to shorten the time for full development of analgesia when using 0.5% hyperbaric tetracaine. Barbotage with 0.5% hyperbaric bupivacaine, however, has the advantage of intensifying and shortening the onset time of a complete motor block.


Assuntos
Raquianestesia/métodos , Bupivacaína/administração & dosagem , Tetracaína/administração & dosagem , Idoso , Método Duplo-Cego , Glucose , Humanos , Masculino , Soluções
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