RESUMEN
BACKGROUND: Use of a single bolus of a hypnotic together with non-depolarizing muscle relaxants for anaesthesia induction may cause inappropriate light levels of anaesthesia (ILLA). The purpose of this study was to compare the incidence of ILLA during anaesthesia induction using either cis-atracurium (CIS) or succinylcholine (SUC). METHODS: Patients (n = 65) received fentanyl and propofol. Relaxants were randomly chosen and were either CIS 0.15 mg/kg, or SUC 1 mg/kg. After achieving relaxation, ILLA were assessed double-blinded by the isolated forearm technique and electroencephalogram -derived values. RESULTS: Time from induction to complete relaxation was 335 ± 55 s with CIS and 141 ± 26 s with SUC. Nine patients in the CIS group (26%), but no patient in the SUC group responded to commands before endotracheal intubation (P < 0.01). During the entire induction up to 1 min after intubation in the CIS group, 24 of 35 patients (68%) showed 31 episodes of ILLA, as defined as responsiveness to commands and spontaneous movements. With SUC, 8 of 30 patients (27%) showed 11 episodes of ILLA (P < 0.01). In patients with ILLA, state entropy (SE) and spectral edge frequency (SEF) were 68 ± 10 (mean ± standard deviation) and 17 ± 4 Hz, respectively, and in patients without ILLA, SE and SEF were 40 ± 14 and 12 ± 3 Hz, respectively (P < 0.01). CONCLUSION: The onset time of a muscle relaxant has substantial impact on the incidence of ILLA during induction of anaesthesia. Entropy and SEF may indicate the presence of ILLA.
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Anestesia , Atracurio/análogos & derivados , Despertar Intraoperatorio/prevención & control , Intubación Intratraqueal/métodos , Fármacos Neuromusculares Despolarizantes/administración & dosificación , Fármacos Neuromusculares no Despolarizantes/administración & dosificación , Succinilcolina/administración & dosificación , Adulto , Anestésicos Intravenosos , Atracurio/administración & dosificación , Método Doble Ciego , Electroencefalografía/efectos de los fármacos , Determinación de Punto Final , Entropía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Intraoperatorio , Estimulación Física , PropofolRESUMEN
BACKGROUND: In analgetic dosages ketamine has stimulatory effects on the cardiovascular system, which limits its use in patients with heart disease. The aim of this study was to clarify whether low-dose S(+)-ketamine used to prevent chronic pain similarly stimulates the cardiovascular system and to determine the impact of propofol dosage on this effect. METHODS: A total of 80 patients undergoing surgery under spinal or epidural anesthesia were randomly assigned to receive double-blinded S(+)-ketamine [0.25 mg/kg body weight (BW) bolus followed by infusion of 0.06 mg/kg BW/h] or placebo in the presence of continuous propofol infusion (2-5 mg/kg BW/h). The heart rate, blood pressure and calculated rate-pressure product (RPP) were monitored. RESULTS: Following the S(+)-ketamine bolus, the heart rate, blood pressure and RPP increased significantly. In the presence of a propofol dosage >3 mg/kg BW/h the stimulatory cardiovascular effect could no longer be observed. CONCLUSION: Even low-dose S(+)-ketamine has a stimulatory effect on the cardiovascular system. This stimulatory effect is nullified in the presence of a continuous propofol infusion at a dosage of more than 3 mg/kg BW/h.
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Anestesia de Conducción , Anestésicos Disociativos , Anestésicos Intravenosos/administración & dosificación , Sistema Cardiovascular/efectos de los fármacos , Ketamina , Propofol/administración & dosificación , Simpatomiméticos , Anestesia Epidural , Anestesia Raquidea , Anestésicos Disociativos/administración & dosificación , Anestésicos Disociativos/efectos adversos , Presión Sanguínea/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Ketamina/administración & dosificación , Ketamina/efectos adversos , Estudios Prospectivos , Riesgo , EstereoisomerismoRESUMEN
BACKGROUND: We use an intubating laryngeal mask (ILM) in preference to an endotracheal tube (ETT) as the ventilatory device during percutaneous dilatational tracheostomy (PDT) to overcome potential problems such as difficult ventilation, accidental extubation, damage of the ETT or of the bronchoscope, and need for additional assistant to secure the airway. We report our experience with this method. METHODS: In this prospective observational study, PDT was performed using the ILM in 86 patients. The insertion of the ILM, the quality of ventilation, and the view of the tracheal puncture site were rated as: 'very good', 'good', 'difficult', and 'not possible with ILM'. RESULTS: The bronchoscope was not damaged during any case, and all PDTs were performed by two physicians, without the need for an additional assistant. PDTs with ILM were successful in 95% of the patients (n=82). The ratings were 'very good' or 'good' in 80% of cases with regards to ventilation, in 90% for identification of relevant structures and tracheal puncture site, and in 85% for the view inside the trachea during PDT. Tracheal re-intubation was required for inadequate ventilation with ILM in four patients. CONCLUSIONS: The advantages of this procedure were lack of damage to the bronchoscope, the need for two instead of three persons to perform the PDT, and the excellent view inside the trachea. We recommend the ILM as a standard device for ventilation during bronchoscope-guided PDT.
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Intubación Intratraqueal/métodos , Máscaras Laríngeas , Traqueostomía/métodos , Adulto , Anciano , Broncoscopía , Humanos , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Estudios Prospectivos , Respiración ArtificialRESUMEN
BACKGROUND: Duration of a migraine disease and hypervigilance are factors which possibly enable the transformation from episodic into chronic migraine. To elucidate this assumption, attentional parameters were measured by recording contingent negative variation (CNV) and correlated with the individual duration of migraine disease. PATIENTS AND METHODS: A total of 28 patients (episodic migraine with or without aura) were compared with 16 healthy controls. CNV analysis included amplitude and habituation calculation. Data were correlated with the individual duration of the migraine disease. The migraine group was divided into two groups based on a median split (short vs long lasting) which were compared by t-tests. RESULTS: Migraine patients produce higher CNV amplitudes than controls. Moreover, migraineurs showed dishabituation while habituation was seen in controls. There was a Pearson correlation coefficient of r = -0.767 between duration of disease and early component of CNV. Patients with long-lasting disease showed lower dishabituation by a higher intercept than patients with short-lasting disease. CONCLUSION: The correlation between duration of disease and attentional parameters and the changing dishabituation can be interpreted as an enhancement in preactivation level in patients with long-lasting migraine. Maybe this change is a prerequisite for transformation into chronic migraine.
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Potenciales Evocados , Trastornos Migrañosos/fisiopatología , Habituación Psicofisiológica , Humanos , Valores de Referencia , Factores de TiempoAsunto(s)
Manejo del Dolor , Grupo de Atención al Paciente , Analgésicos/efectos adversos , Analgésicos/uso terapéutico , Analgésicos Opioides/efectos adversos , Analgésicos Opioides/uso terapéutico , Antiinflamatorios no Esteroideos/efectos adversos , Antiinflamatorios no Esteroideos/uso terapéutico , Bloqueo Nervioso Autónomo , Enfermedad Crónica , Quimioterapia Combinada , Alemania , Humanos , Medicina Interna , Dolor/etiología , Dimensión del Dolor , Cuidados PaliativosRESUMEN
UNLABELLED: The purpose of the study was to investigate the effect of intraoperative hyperventilation on postoperative cognitive functions. METHODS: A total of 120 patients (60 older and 60 younger than 65 years old) were allocated randomly to group I "hyperventilation" (p(et)CO(2)=30 mmHg) or group II "normoventilation" (p(et)CO(2)=45 mmHg). Before the operation and on days 1, 3 and 6 after the operation, a battery of neuropsychological tests was performed (concentration endurance test d2, number connection test, digit symbol test). A decline of 20% in at least one test was regarded as postoperative cognitive deficit (POCD). Anaesthesia was maintained with isoflurane in nitrous oxide/oxygen supplemented with fentanyl. RESULTS: In all patients pooled, POCD was present in 26 patients (22%). In patients older than 65 years, POCD was present in 3 cases after hyperventilation and 13 cases after normoventilation ( p<0.01). In younger subjects, 5 cases of POCD were diagnosed in each ventilation group. Furthermore, POCD was more severely pronounced in older patients after normoventilation. CONCLUSION: In older patients, POCD occurred more frequently after intraoperative normoventilation. We assume that a reduced amount of noxious substances reach the brain after hyperventilation, because hyperventilation reduces the cerebral blood flow.
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Envejecimiento/psicología , Anestesia General/efectos adversos , Trastornos del Conocimiento/prevención & control , Complicaciones Posoperatorias/prevención & control , Respiración Artificial , Anciano , Atención/fisiología , Circulación Cerebrovascular/fisiología , Trastornos del Conocimiento/fisiopatología , Trastornos del Conocimiento/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Complicaciones Posoperatorias/fisiopatología , Complicaciones Posoperatorias/psicologíaRESUMEN
BACKGROUND: S-100 protein serum concentration (S-100) serves as a marker of cerebral ischemia in cardiac surgery, head injury and stroke. In these circumstances S-100 corresponds well with the results of neuropsychological tests. The aim of the present study was to investigate the value of S-100 and neuron specific enolase (NSE) in reflecting postoperative cognitive deficit (POCD) after general surgical procedures. METHODS: One hundred and twenty patients undergoing vascular, trauma, urological or abdominal surgery were investigated. Serum values of S-100 and NSE were determined preoperatively and 0.5, 4, 18 and 36 h postoperatively. Neuropsychological tests for detecting POCD were performed preoperatively and on day 1, 3, and 6 after the operation. A decline of more than 10% in neuropsychological test results was regarded as POCD. Furthermore, we retrospectively compared the S-100 in patients with and without POCD in different types of surgery. RESULTS: According to our definition, forty-eight patients had POCD (95% confidence interval: 37.5-58.5). These patients showed higher serum concentrations of S-100 (median 024 ng/ml; range 0.01-3.3 ng/ml) compared with those without POCD (n=69; median 0.14 ng/ml; range 0-1.34 ng/ml) 30 min postoperatively (P=0.01). Neuron specific enolase was unchanged during the course of the study. Differences of S-100 in patients with and without POCD were found in abdominal and vascular surgery but not in urological surgery. CONCLUSION: When all patients are pooled, S-100 appears to be suitable in the assessment of incidence, course and outcome of cognitive deficits. We suspect that in some surgical procedures, such as urological surgery, S-100 appears to be of limited value in detecting POCD. Neuron specific enolase did not reflect neuropsychological dysfunction after noncardiac surgery.
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Anestesia General , Trastornos del Conocimiento/sangre , Trastornos del Conocimiento/etiología , Complicaciones Posoperatorias/sangre , Proteínas S100/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Biomarcadores , Trastornos del Conocimiento/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Fosfopiruvato Hidratasa/sangre , Complicaciones Posoperatorias/psicología , Estudios RetrospectivosRESUMEN
OBJECTIVES: Delirium is the most common acute organic psychosis postoperatively, and occurs more frequently in the elderly than anticipated. The abbreviated mental test (AMT) is a widely used cognitive test in Great Britain. The present study assessed the AMT in a German version for diagnosis of postoperative delirium. METHODS: 40 patients (older than 65 years), scheduled for total knee or hip replacement, were tested repeatedly for delirium according to the ICD-10. These patients were investigated with the AMT simultaneously by a second investigator. RESULTS: Delirium was present in four orthopaedic patients (10 %) and was diagnosed correctly in these patients by the AMT. All but one patient without delirium showed no deterioriation in AMT score. CONCLUSION: As in Great Britain, the AMT in its German version is useful in diagnosing delirium. We recommend the use of the AMT preoperatively in elderly patients at risk for delirium.
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Cognición , Delirio/etiología , Complicaciones Posoperatorias/psicología , Pruebas Psicológicas , Anciano , Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Sesgo , Delirio/diagnóstico , Femenino , Alemania , Humanos , Lenguaje , Masculino , Reproducibilidad de los Resultados , Reino UnidoRESUMEN
The relation between a paper-pencil test of sustained attention (d2-letter cancellation test, d2-LCT) and the contingent negative variation (CNV) as a cortical slow potential was calculated in 23 healthy undergraduate students. Both d2-LCT and CNV reflect selective, focussed attention. There was a Pearson correlation coefficient of r = -0.670 between the early component of the CNV and the number of checked letters in d2-LCT, indicating significant differences in early CNV between low and high performance in d2-LCT. The results showed a linear relationship between paper-pencil registered attentional properties and the cortically recorded early component of CNV.
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Atención/fisiología , Corteza Cerebral/fisiología , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/fisiopatología , Cognición/fisiología , Neuronas/fisiología , Desempeño Psicomotor/fisiología , Adulto , Afecto/fisiología , Factores de Edad , Trastornos del Conocimiento/psicología , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Tiempo de Reacción/fisiología , Factores SexualesRESUMEN
BACKGROUND: Propofol-sufentanil anaesthesia has become popular during cardiac surgery for its titrability and short recovery time. Avoidance of awareness is a major goal during cardiac surgery. We therefore investigated the dose-response relationship of propofol and cortical responses (mid-latency auditory evoked potentials, MLAEP). METHODS: One hundred patients undergoing cardiac surgery were investigated. Basic anaesthesia was performed with sufentanil (4.5 microg kg(-1) h(-1)) / flunitrazepam (9 microg kg(-1) h(-1)) infusion (control group); the other groups received in addition a loading dose of propofol 2 mg kg(-1) and a maintainance infusion of 1-3.5 mg kg(-1) h(-1). MLAEP were evaluated by using Pa/Nb-amplitudes and Nb-latencies. Haemodynamics were monitored by ECG, arterial blood pressure and cardiac function with pulmonary artery catheterization. RESULTS: In the control group, median amplitude of MLAEP decreased by 50% with a wide range, but were detectable in >90% of patients throughout surgery. Propofol suppressed amplitude Pa/Nb of MLAEP dose dependently. With 3.5 mg kg(-1) h(-1) amplitudes disappeared in >40% of patients throughout cardiac surgery. Median Nb-latencies increased in the control group from 44 to a range from 50 to 60 ms. In groups with propofol >2 mg kg(-1) h(-1), Nb-latencies, detectable in the patients without complete suppression of MLAEP, increased to median 60 ms. Haemodynamic parameters and cardiac function did not differ among the groups. The use of vasopressors was not increased even with the highest propofol dose used. CONCLUSION: The dose-response effect of propofol on auditory evoked potentials reveals that combining a loading dose of 2 mg kg-1 with a consecutive infusion of 3.5 mg kg(-1) h(-1) significantly suppresses MLAEP during cardiac surgery. Thus, auditory information may not be processed and awareness with recall becomes unlikely.
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Anestésicos Intravenosos/farmacología , Procedimientos Quirúrgicos Cardíacos , Potenciales Evocados Auditivos/efectos de los fármacos , Propofol/farmacología , Adolescente , Adulto , Anciano , Relación Dosis-Respuesta a Droga , Hemodinámica/efectos de los fármacos , Humanos , Persona de Mediana EdadRESUMEN
Today, a wide range of efficient analgesic and non-analgesic drugs for the treatment of back pain are available. However, drugs should never be the only mainstay of a back pain treatment program. Non-steroidal antiinflammatory drugs (NSAID) are widely used in acute back pain. NSAIDs prescribed at regular intervals are effective to reduce simple back pain. The different NSAIDs are effective for the reduction of this pain. They have serious adverse effects, particularly at high doses, in the elderly, and on long-term administration. The new cyclooxygenase II-inhibitors have less gastrointestinal complications. But the long-term experiences are limited up to now. Considerable controversy exists about the use of opioid analgesics in chronic noncancer pain. Many physicians are concerned about the effectiveness and adverse effects of opioids. Other clinicians argue that there is a role for opioid therapy in chronic noncancer pain, e. g. especially in chronic low back pain. There is a low incidence of organ toxicity in patients who respond to opioids. The incidence of abuse and addiction is likewise relatively low. The potential for increased function and improved quality of life seems to outweigh the risks. However, there is a lack of randomised controlled trials (RCT) on opioid therapy in a multimodal pain treatment approach. Clinical experience and some studies suggest administration of sustained release opioids because of better comfort for the patient and less risks for addiction. The opioids should be selected due to the specific side effects of the different drugs. For patients with pre-existing constipation transdermal fentanyl should be preferred. Antidepressant medications have been used for the treatment of chronic back pain, though there is only little scientific evidence for their effectiveness. There is no evidence for the use of antidepressants in acute low back pain. Trials of muscle relaxants for patients with acute back pain have used a wide range of agents, e. g. benzodiazepines. They mostly reduce acute back pain, but they have significant adverse effects including drowsiness and psychological and physical dependence even after relatively short treatment. Benzodiazepines are not indicated in the treatment of chronic back pain. Drugs are sometimes necessary for the patients to begin and persevere a multimodal treatment program. Drug therapy should be terminated as soon as other treatment strategies succeed. Unfortunately, no studies exist evaluating the place of analgesics within a multimodal treatment program.
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Dolor de Espalda/terapia , Analgésicos Opioides/efectos adversos , Analgésicos Opioides/uso terapéutico , Antiinflamatorios no Esteroideos/efectos adversos , Antiinflamatorios no Esteroideos/uso terapéutico , Antidepresivos/efectos adversos , Antidepresivos/uso terapéutico , Dolor de Espalda/fisiopatología , Enfermedad Crónica , Terapia Combinada , Humanos , Neoplasias/fisiopatologíaRESUMEN
UNLABELLED: S-100 protein and neuron-specific enolase (NSE) serum concentrations serve as markers of cerebral damage in cardiac surgery, neurology, or after head injury. In these circumstances, S-100 and NSE levels correspond with the results of neuropsychological tests. The present study investigated the diagnostic value in orthopaedic patients after joint replacement. METHODS: Forty patients scheduled for elective hip or knee arthroplasty were investigated. Serum values of NSE and S-100 were determined preoperatively and 30 min and 4, 18, and 36 h postoperatively. Neuropsychological tests (syndrome short test, SKT, delirium assessment according to DSM IV) were performed preoperatively and two, three, and four days following surgery. General anaesthesia was induced with fentanyl and etomidate and maintained with isoflurane in oxygen/air. FINDINGS: The S-100 increased from a median of 0.04 ng/ml (range 0.004-0.19 ng/ml) preoperatively to 1.03 ng/ml (range 0.18-3.65 ng/ml) at 30 minutes postoperatively (P < 0.0001). These levels returned to normal in the course of the following 2 days. NSE values were 8.55 ng/ml (range 4.6-14.9 ng/ml) preoperatively and 7.07 ng/ml (range 4-16.4 ng/ml) postoperatively (P = 0.167). There were no differences in serum concentrations of S-100 and NSE between normal patients and those with postoperative cognitive deficit. Furthermore, no correlation was found between the serum marker and neuropsychological tests. INTERPRETATION: Obviously, increased NSE levels seem to indicate cerebral damage only in more severe cases. S-100 does not seem to be brain-specific in patients undergoing orthopaedic surgery. Therefore, the value of S-100 in the assessment of brain disorders is limited.
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Anestesia General/efectos adversos , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/psicología , Fosfopiruvato Hidratasa/sangre , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/psicología , Proteínas S100/sangre , Anciano , Biomarcadores , Trastornos del Conocimiento/etiología , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Valor Predictivo de las PruebasRESUMEN
PURPOSE: To determine the magnitude of the potentiation of rocuronium by desflurane, isoflurane and sevoflurane 1.5 MAC anaesthesia. METHODS: In a prospective, randomised, study in 80 patients, the cumulative dose-effect curves for rocuronium were determined during anaesthesia with desflurane, sevoflurane and isoflurane (with N2O 70%, 15 min steady state) or total intravenous anaesthesia (TIVA) using propofol/fentanyl. Neuromuscular block was assessed by acceleromyography (TOF-Guard) after train-of-four (TOF) stimulation of the ulnar nerve (2 Hz every 12 sec, 200 microseconds duration). Rocuronium was administered in increments of 100 micrograms.kg-1 until first twitch (T1) depression > 95%. RESULTS: Rocuronium led to more pronounced T1 depression with desflurane or sevoflurane anaesthesia than with TIVA. The ED50 and ED95 were lower during desflurane (95 +/- 25 and 190 +/- 80 micrograms.kg-1) and sevoflurane (120 +/- 30 and 210 +/- 40 micrograms.kg-1) than with TIVA (150 +/- 40 and 310 +/- 90 micrograms.kg-1) (P < .01), while the difference was not significant for isoflurane (130 +/- 40 and 250 +/- 90 micrograms.kg-1). Following equi-effective dosing (T1 > 95%) the duration to 25% T1 recovery, recovery index (25/75), and TOF0.70 was: 13.2 +/- 1.8, 12.7 +/- 3.4, and 26.9 +/- 5.7 min during anaesthesia with desflurane; 15.5 +/- 5.0, 11.4 +/- 3.8, and 31.0 +/- 6.0 min with sevoflurane; 13.9 +/- 4.7, 10.7 +/- 3.3, and 26.3 +/- 8.9 min with isoflurane; and 13.9 +/- 3.9, 11.3 +/- 5.7, and 27.5 +/- 8.2 min with TIVA anaesthesia (P: NS). CONCLUSION: Interaction of rocuronium and volatile anaesthetics resulted in augmentation of the intensity of neuromuscular block but did not result in significant effects on duration of or recovery from the block.
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Androstanoles/farmacología , Anestesia por Inhalación , Anestésicos por Inhalación/farmacología , Isoflurano/análogos & derivados , Isoflurano/farmacología , Éteres Metílicos/farmacología , Bloqueo Neuromuscular , Fármacos Neuromusculares no Despolarizantes/farmacología , Adulto , Androstanoles/administración & dosificación , Periodo de Recuperación de la Anestesia , Anestesia Intravenosa , Anestésicos por Inhalación/administración & dosificación , Anestésicos Intravenosos/administración & dosificación , Anestésicos Intravenosos/farmacología , Desflurano , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Estimulación Eléctrica , Femenino , Fentanilo/administración & dosificación , Fentanilo/farmacología , Humanos , Isoflurano/administración & dosificación , Masculino , Éteres Metílicos/administración & dosificación , Persona de Mediana Edad , Contracción Muscular/efectos de los fármacos , Fármacos Neuromusculares no Despolarizantes/administración & dosificación , Propofol/administración & dosificación , Propofol/farmacología , Estudios Prospectivos , Rocuronio , Sevoflurano , Factores de Tiempo , Nervio Cubital/efectos de los fármacosRESUMEN
BACKGROUND: In a retrospective analysis of intraoperative somatosensory evoked potential (SEP) results during carotid artery surgery we found some cases with postoperative neurologic deficits, surprisingly without significant SEP changes. METHODS: Median nerve SEP were monitored as usual. Indication for selective shunting was a complete loss of amplitude N20/P25 in the first period of the investigation, later on a 50% reduction, or a prolongation of the central conduction time (CCT) of about 1.5 ms after cross-clamping. Anaesthesia was maintained with isoflurane in N2O/O2, fentanyl and atracurium. RESULTS: Over a 3-year period 146 patients were monitored. Indications were: transient ischaemic attacks (TIA) (n=51), stroke (n=23), stroke with residuals (n=39), asymptomatical stenosis (n=29), subclavian steal syndrome (n=4). Twenty-four patients received an intraluminal shunt following SEP alterations. Postoperatively, 5 patients (3.4%) had symptoms of intraoperative brain ischaemia (stroke n=2, TIA n=3), 4 of them showing only minor intraoperative SEP alterations; 1 received a shunt because of CCT prolongation. Four of these 5 patients had cerebral neurologic deficiency preoperatively. CONCLUSION: Since some authors have found a 100% sensitivity of intraoperative SEP, it is remarkable, that 1 patient with postoperative stroke and 3 patients with TIA had no significant SEP changes intraoperatively. We suppose there was an association with preoperative neurological deficits resulting from previous strokes. In such cases, regional critical ischaemia may apparently occur outside the sensory pathway monitored with SEP.
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Estenosis Carotídea/cirugía , Trastornos Cerebrovasculares/fisiopatología , Endarterectomía Carotidea , Potenciales Evocados Somatosensoriales/fisiología , Monitoreo Intraoperatorio , Anciano , Anestésicos por Inhalación/administración & dosificación , Anestésicos Intravenosos/administración & dosificación , Derivación Arteriovenosa Quirúrgica , Atracurio/administración & dosificación , Isquemia Encefálica/etiología , Puente Cardiopulmonar , Estenosis Carotídea/fisiopatología , Trastornos Cerebrovasculares/etiología , Trastornos Cerebrovasculares/cirugía , Endarterectomía Carotidea/efectos adversos , Femenino , Fentanilo/administración & dosificación , Humanos , Complicaciones Intraoperatorias , Ataque Isquémico Transitorio/fisiopatología , Ataque Isquémico Transitorio/cirugía , Isoflurano/administración & dosificación , Masculino , Nervio Mediano/fisiología , Persona de Mediana Edad , Conducción Nerviosa , Vías Nerviosas/fisiopatología , Fármacos Neuromusculares no Despolarizantes/administración & dosificación , Neuronas Aferentes/fisiología , Óxido Nitroso/administración & dosificación , Oxígeno/administración & dosificación , Complicaciones Posoperatorias , Reproducibilidad de los Resultados , Estudios Retrospectivos , Síndrome del Robo de la Subclavia/fisiopatología , Síndrome del Robo de la Subclavia/cirugíaRESUMEN
RATIONALE AND OBJECTIVES: The authors investigate the cerebral effects of selective carotid angiography with carbon dioxide (CO2). METHODS: In 6 pigs, CO2 was injected into the carotid artery with consecutively increasing doses. Cerebral function was monitored with two-channel electroencephalography and somatosensory evoked potentials (SEPs). After the experiment the brains were investigated histopathologically. RESULTS: Initial doses led to reversible decreases in electroencephalograph power by 40% to 80%. Further doses result in partly nonreversible electroencephalographic changes. Somatosensory evoked potential latencies (n = 5) were not changed. Amplitudes were not affected in low dose ranges up to 40 mL CO2. Higher CO2 doses led to different changes. There were no SEP amplitude reductions (n = 1), as well as reversible (n = 2) and nonreversible (n = 2) SEP amplitude reductions. Histopathologically, edema (n = 6), edema necrosis (n = 2), and destroyed cells as a sign of ischemia (n = 2) were found. CONCLUSIONS: Administering CO2 in brain supplying arteries impairs the cerebral function. Consecutive, increasing doses lead to partly nonreversible electroencephalographic and SEP changes and brain tissue damages.
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Angiografía/métodos , Encéfalo/efectos de los fármacos , Dióxido de Carbono , Arterias Carótidas/diagnóstico por imagen , Electroencefalografía/métodos , Potenciales Evocados Somatosensoriales/efectos de los fármacos , Angiografía/efectos adversos , Animales , Encéfalo/patología , Encéfalo/fisiopatología , Isquemia Encefálica/inducido químicamente , Isquemia Encefálica/patología , Dióxido de Carbono/administración & dosificación , Dióxido de Carbono/efectos adversos , Relación Dosis-Respuesta a Droga , Edema/inducido químicamente , Edema/patología , Electroencefalografía/efectos de los fármacos , Infusiones Intraarteriales , Necrosis , Proyectos Piloto , Porcinos , Porcinos EnanosRESUMEN
We examined the effect of high frequency transcutaneous electrical nerve stimulation on the onset of brachial plexus block. Three groups of patients scheduled for surgery of the hand had a local anaesthetic block performed with 40 ml mepivacaine 1.5% using the axillary approach. After injection of the local anaesthetic transcutaneous electrical nerve stimulation was applied for 15 min either to the median nerve or the ulnar nerve; no stimulation was applied in the control group. Before and for 45 min after, the injection of local anaesthetic touch perception, pin prick, motor strength and skin temperature were tested by a blinded investigator in the areas supplied by the median, musculocutaneous, radial and ulnar nerves. There were no differences in the onset of block between the groups. Thus, the frequency-dependent action of local anaesthetics could not be demonstrated.
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Plexo Braquial , Bloqueo Nervioso , Estimulación Eléctrica Transcutánea del Nervio , Adulto , Anciano , Anestésicos Locales/farmacología , Femenino , Mano/cirugía , Humanos , Masculino , Nervio Mediano , Mepivacaína/farmacología , Persona de Mediana Edad , Movimiento/efectos de los fármacos , Sensación/efectos de los fármacos , Método Simple Ciego , Temperatura Cutánea/efectos de los fármacos , Factores de Tiempo , Nervio CubitalRESUMEN
PURPOSE: To evaluate the short-term effectiveness and biocompatibility of Dacron-covered stent-grafts for percutaneous treatment of carotid aneurysms. MATERIALS AND METHODS: In eight swine, nine aneurysms were created surgically in the common carotid artery. Percutaneous treatment was performed with Dacron-covered stent-grafts. Seven of eight swine underwent follow-up angiography at 2, 3, 4, and 5 weeks after stent implantation. Histologic examinations of tissue from the site of stent implantation were performed at the same intervals. RESULTS: Initial closing off of the aneurysm was possible in all swine. Angiographic follow-up revealed patency of only one Dacron-covered stent-graft after 2 weeks. In six of seven swine, the stent was occluded on the follow-up angiogram. One of the swine died of unclear cause after 1 week. The stent-graft of this swine was not occluded. In all Dacron-covered stent-grafts, inflammatory reaction with granulocyte infiltration was found next to the Dacron material. CONCLUSION: Primary treatment of carotid aneurysms with Dacron-covered stent-grafts is effective. However, the short-term patency rate is poor, which probably can be attributed to the limited biocompatibility of the Dacron cover. An acute inflammatory reaction against Dacron seems responsible for the poor patency rate.
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Materiales Biocompatibles , Prótesis Vascular , Enfermedades de las Arterias Carótidas/cirugía , Oclusión de Injerto Vascular/patología , Aneurisma Intracraneal/cirugía , Tereftalatos Polietilenos , Stents , Angiografía de Substracción Digital , Animales , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/patología , Arteria Carótida Común/diagnóstico por imagen , Arteria Carótida Común/patología , Femenino , Oclusión de Injerto Vascular/diagnóstico por imagen , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/patología , Radiología Intervencionista , Porcinos , Factores de Tiempo , Grado de Desobstrucción VascularRESUMEN
Some 20-40% of diabetics suffer from an autonomic neuropathy. This complication of diabetes mellitus impairs the regulation and the reflexes of the cardiovascular system. This study compares the cardiovascular characteristics of diabetics and nondiabetic control patients. METHODS. 21 patients (11 diabetics, 10 nondiabetics) undergoing ophthalmic surgery were investigated. They were tested preoperatively for autonomic cardiovascular dysfunction by application of four established tests. These were: heart rate responses to the Valsalva maneuver, deep breathing and standing up (30/15 test) and the Schellong test. The anaesthesia was induced with fentanyl (0.1 mg), etomidate (2.5 mg/kg) and succinyl choline (1.5 mg) and maintained with oxygen/nitrous oxide (1.4:3 l/min) and isoflurane (0.2-0.8 vol%). Blood pressure and heart rate were automatically measured every minute during induction of anaesthesia and every 3 min during anaesthesia. Additionally the heart rate response to 0.5 mg atropine i.v. was evaluated. RESULTS. The autonomic function tests revealed pathologic reactions in all diabetics (two early, six definitive, three severe) and none in controls. Remarkable cardiovascular events occurred exclusively in the diabetic group, especially during induction of anaesthesia. The systolic blood pressure (SAP) increased in diabetics from a preinduction value of 150 mmHg (median, range 105-205 mmHg) to a maximum of 200 mmHg (160-250 mmHg) after intubation, in controls from 130 (100-150 mmHg) to 170 (110-190 mmHg). Following this peak, SAP fell in diabetics to 120 mmHg (80-160 mmHg), in controls to 110 (100-140 mmHg). Two diabetics had to be treated because of an SAP exceeding 220 mmHg, two other diabetics because of an SAP below 80 mmHg. After atropine administration the heart rate of diabetics showed a median increase of 15% (range 0-40%). In four diabetics, however, the increase was less than 10%. In control patients the increase was 50% (40-80%). All patients with severe cardiovascular reactions during induction of anaesthesia and with heart rate elevation following atropine of less than 10% had a definite or severe neuropathy of the autonomic nervous system revealed by the tests. DISCUSSION. In the only slightly stressful ophthalmic surgery, remarkable events were noted particularly during the induction of anaesthesia. The critical decreases and increases of SAP might be related to the autonomic dysfunction, because of the hypersensitivity of a partly damaged autonomic nervous system or its impaired function. This led to a loss of heart rate variation and adequate blood vessel tone. The severe cardiovascular reactions always went along with clearly pathologic findings in the tests performed. Normal test results in diabetics implied normal cardiovascular reactions, as could be observed in nondiabetics. CONCLUSION. Abnormal cardiovascular reactions in diabetics must be kept in mind. The simple tests specified here can identify such predisposed patients.