RESUMEN
A new continuous noninvasive blood pressure measurement device, the T-Line Tensymeter TL100 (Tensys Medical Inc., San Diego, CA, USA) which enables avoidance of arterial cannulation has been developed. We compared the values obtained using the T-Line values to simultaneous arterial line measurements in patients undergoing general anaesthesia with induced hypotension. Twenty-five patients, aged 18-70 years, were studied. The T-Line and arterial line were positioned on the contralateral wrists. Intra-operative, real-time, blood pressure data were electronically captured and stored on a computer. Bland-Altman plots and 95% limits of agreement show that the majority of T-Line data points were within 5 mmHg of the arterial line measurements (67%) and agreement was within 15 mmHg in 94.6% or more of all measurements. There was virtually no distinguishable error over the course of surgery using the device. In conclusion, the T-Line measurements correlate with arterial measurements during anaesthesia in which there were periods of both normotensive and hypotensive anaesthesia. The T-Line Tensymeter represents a noninvasive alternative to an arterial line in cases when arterial blood sampling is not required.
Asunto(s)
Monitores de Presión Sanguínea , Hipotensión Controlada , Monitoreo Intraoperatorio/instrumentación , Adolescente , Adulto , Anciano , Anestesia General , Antropometría , Presión Sanguínea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Columna Vertebral/cirugíaRESUMEN
OBJECTIVES: This in vitro study tested the influence of diverse stress simulation parameters on the fracture strength of all-ceramic three-unit fixed partial dentures (FPDs). METHODS: All-ceramic FPDs made of Empress 2 (Ivoclar-Vivadent, FL) were exposed to thermal cycling and mechanical loading (TCML) with varying loading parameters such as chewing force (amount, frequency), thermal loading, lateral jaw motion, abutment material, artificial periodontium or antagonistic denture. To investigate the influence of the abutment material, human teeth, polymer abutments and alloy abutments were used. Two different TCML devices with pneumatic or weight loading were compared. FPDs without aging were used as a control. RESULTS AND SIGNIFICANCE: Combined thermal and mechanical loading significantly reduced the FPD fracture resistance from 1832N to 410N. Duplication of chewing frequency, phase load increase or additional lateral movement did not effect the results. Increasing chewing force, artificial periodontium, and antagonist or abutment material reduced the fracture resistance of the tested FPDs. Different devices with weight or pneumatic loading had no significant influence on the loading capacity of the FPDs. Artificial aging should be performed combining thermal cycling with mechanical loading. Simulation of the artificial periodontium, human antagonists and abutments should be included to achieve a significant aging.
Asunto(s)
Porcelana Dental/química , Dentadura Parcial Fija , Compuestos de Litio/química , Fuerza de la Mordida , Pilares Dentales , Aleaciones Dentales/química , Materiales Dentales/química , Fracaso de la Restauración Dental , Diseño de Dentadura , Dentaduras , Humanos , Mandíbula/fisiología , Ensayo de Materiales , Modelos Biológicos , Periodoncio/fisiología , Polímeros/química , Estrés Mecánico , Temperatura , Termodinámica , Diente/fisiología , Diente ArtificialRESUMEN
Increased cortisol levels have been observed in patients suffering from a number of metabolic and psychiatric disorders. In some of these disorders a causal relationship has been suggested between the increased cortisol secretion and the observed clinical phenomena. Glucocorticoid receptor antagonists which block cortisol effects might have a benefit in both the diagnosis and treatment of these disorders. Selective glucocorticoid receptor antagonists with in vivo potency have not been described thus far, partly due to the similarity between the glucocorticoid and progesterone receptors. In the present studies, we report on three different chemical classes derived from the glucocorticoid/progestagen antagonist RU486. Selected compounds from the classes 11-monoaryl steroids, 11,21-bisaryl steroids and 11-aryl, 16-hydroxy steroids proved to be selective glucocorticoid receptor binders with in vivo antagonistic activity. Most compounds were able to pass the blood-brain barrier. These compounds offer the opportunity to investigate and possibly treat patients with a disturbed hypothalamus-pituitary-adrenal axis without side effects caused by an antiprogestagenic action.
Asunto(s)
Hidrocortisona/fisiología , Receptores de Glucocorticoides/antagonistas & inhibidores , Animales , Barrera Hematoencefálica , Antagonistas de Hormonas/farmacología , Humanos , Hidrocortisona/metabolismo , Mifepristona/farmacología , Ratas , Receptores Citoplasmáticos y Nucleares/efectos de los fármacos , Receptores Citoplasmáticos y Nucleares/metabolismo , Receptores de Mineralocorticoides/efectos de los fármacos , Receptores de Progesterona/efectos de los fármacosRESUMEN
BACKGROUND: We investigated the hypothesis that manipulation of cardiac output (CO) with esmolol (Es) or ephedrine (E) affects the onset time of rocuronium. METHODS: Following anesthesia induction, 33 patients received E (70 micro g kg-1), Es (500 micro g kg-1) or placebo (P) 30 s before rocuronium (0.6 mg kg-1) administration. Cardiac output was measured non-invasively after intubation every 3 min. The interval from the end of rocuronium administration to the disappearance of all twitches was considered to be the onset time. RESULTS: Onset time was shorter after E (52.2 +/- 16.5 s) and longer after Es (114.3 +/- 11.1 s) compared with P (87.4 +/- 7.3 s) (P < 0.0001). Cardiac output increased (P < 0.05) in group E for 15 min after rocuronium. In group Es, CO decreased (P < 0.05) at 3 and 6 min. Cardiac output was higher in group E vs. group Es, 3-6 min post administration of rocuronium (P=0.015). CONCLUSION: Pretreatment with E or Es appears to affect the onset time of rocuronium by altering CO as measured with the NICO (Non-Invasive Cardiac Output) monitor (Novametrix Medical Systems Inc., Willingford, CO).
Asunto(s)
Androstanoles/farmacología , Gasto Cardíaco/efectos de los fármacos , Efedrina/farmacología , Fármacos Neuromusculares no Despolarizantes/farmacología , Propanolaminas/farmacología , Adolescente , Adulto , Anestésicos por Inhalación/farmacología , Dióxido de Carbono/análisis , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico , Unión Neuromuscular/efectos de los fármacos , Unión Neuromuscular/fisiología , Estudios Prospectivos , Rocuronio , Factores de TiempoAsunto(s)
Plexo Lumbosacro , Bloqueo Nervioso , Dolor Postoperatorio/terapia , Enfermedad Aguda , Niño , Fémur , Fracturas Óseas/cirugía , Humanos , Lactante , Masculino , Fracturas Craneales/cirugíaRESUMEN
BACKGROUND: The effort to decrease hospital stays and to increase operating room efficacy has become an important consideration in the practice of anesthesia. METHODS: Fifty-three patients who underwent shoulder rotator cuff repair in the sitting position were divided into four groups according to the anesthesia technique used: Group 1 (general anesthesia), Group 2 (interscalene block), Group 3 (interscalene combined with general anesthesia) and Group 4 (general anesthesia combined with local injection of local anesthetics). Interscalene blocks were performed preoperatively, using a nerve stimulator. After appropriately locating the brachial plexus, a mixture of 40 ml of 2% lidocaine and 0.5% bupivacaine (v/v) was injected. RESULTS: As compared to general anesthesia, the use of an interscalene block alone reduced the following operating room times: 1) from the patient's arrival in the operating room to the beginning of surgery and 2) from the end of surgery to the patient's departure from the operating room. Use of the interscalene block also resulted in a reduction of recovery time when compared to Groups 1, 3 and 4 by 40, 56 and 66%, respectively. Compared to Group 1, this anesthesia technique was furthermore associated with a 64% decrease in the number of patients hospitalized overnight. CONCLUSIONS: This study confirms that the interscalene block as sole anesthesia technique is safe and effective and can contribute to shorten the hospital length of stay of patients undergoing shoulder rotator cuff surgery.
Asunto(s)
Anestesia , Bloqueo Nervioso , Procedimientos Ortopédicos , Manguito de los Rotadores/cirugía , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosAsunto(s)
Anestesiología/educación , Internado y Residencia , Agujas , Bloqueo Nervioso/métodos , HumanosRESUMEN
This study was designed to determine the effects of continuous femoral infusion (CFI) on total knee arthroplasty recovery. A total of 92 patients were distributed in 3 groups: Patients in group 1 received general anesthesia followed by patient-controlled analgesia (PCA) with morphine (n = 33), patients in group 2 received 3-in-1 and sciatic blocks followed by CFI (n = 29), and patients in group 3 received epidural analgesia (n = 30). Blocks reduced postoperative morphine requirement by 74% (vs group 1; P<.05) and 35% (vs group 3; P<.05). Blocks provided better recovery than PCA with morphine or an epidural. The use of CFI was associated with a reduction of postoperative bleeding by 72% (vs group 1; P<.05) and allowed better performance on continuous passive motion. CFI was associated with a 90% decrease in serious complications and a 20% decrease in the length of hospitalization. CFI represents a better alternative than PCA or epidural analgesia for postoperative pain management and immediate rehabilitation after total knee arthroplasty.
Asunto(s)
Analgesia Controlada por el Paciente , Anestesia Epidural , Anestésicos Locales/administración & dosificación , Artroplastia de Reemplazo de Rodilla , Bloqueo Nervioso/métodos , Dolor Postoperatorio/prevención & control , Adulto , Anciano , Humanos , Infusiones Intravenosas , Persona de Mediana Edad , Resultado del TratamientoAsunto(s)
Analgésicos Opioides/efectos adversos , Analgésicos Opioides/uso terapéutico , Procedimientos Ortopédicos , Dolor Postoperatorio/tratamiento farmacológico , Sufentanilo/efectos adversos , Sufentanilo/uso terapéutico , Analgésicos Opioides/administración & dosificación , Humanos , Inyecciones , Espacio Subaracnoideo , Sufentanilo/administración & dosificaciónRESUMEN
The constant search for increased efficiency and reduction of hospital length of stay has led to an increase number of major orthopedic procedures performed as outpatients and the increase in the associated intensity and duration of acute postoperative pain. Although, it is well established that single peripheral blocks provide adequate anesthesia and excellent immediate postoperative analgesia in patients undergoing minor ambulatory orthopedic surgery, the postoperative acute pain benefit is limited to less than 24 hours. However, many patients required over 24 hours of intensive postoperative analgesia. Furthermore the need for immediate postoperative physical therapy in orthopedics dictates that local anesthetics be chosen on the basis of their safety and ability to produce preferential sensory blocks. As early as 1946, Ansbro proposed the use of continuous nerve blocks to prolong the duration of analgesia of nerve block technique during anesthesia. Continuous nerve blocks have also been used for the acute postoperative pain control of patients undergoing major orthopedic surgery as in-patients. This technique has been proven to be safe and effective in controlling acute postoperative pain and improve functional outcome. The recent introduction of safer local anesthetics producing preferential sensory blocks along with the development of ambulatory pumps has allow to extend the use of these continuous block techniques to ambulatory patients. Recent development also included the use of cox2 inhibitors along with cold maximize postoperative analgesia. This multimodal approach has been proven to be safe and efficacious as much for resting pain than pain associated with exercise.
Asunto(s)
Procedimientos Quirúrgicos Ambulatorios , Anestesia de Conducción , Procedimientos Ortopédicos , Humanos , Bloqueo Nervioso , Dolor Postoperatorio/prevención & control , Sistema Nervioso PeriféricoAsunto(s)
Complicaciones Intraoperatorias/inducido químicamente , Hipersensibilidad al Látex/complicaciones , Atelectasia Pulmonar/inducido químicamente , Niño , Femenino , Humanos , Complicaciones Intraoperatorias/inmunología , Hipersensibilidad al Látex/inmunología , Atelectasia Pulmonar/inmunologíaRESUMEN
IMPLICATIONS: The authors demonstrate that the combination of single and continuous peripheral nerve blocks allows the control of involuntary movements in patients undergoing awake craniotomy.
Asunto(s)
Craneotomía , Extremidades/inervación , Inmovilización , Bloqueo Nervioso , Lóbulo Temporal/cirugía , Anestésicos Locales , Mapeo Encefálico , Bupivacaína , Humanos , Masculino , Persona de Mediana Edad , Movimiento , Psicocirugía , Convulsiones/cirugía , VigiliaRESUMEN
Three carotenoids, spheroidene, 3,4-dihydrospheroidene and 3,4,5,6-tetrahydrospheroidene, having 8, 9 and 10 conjugated carbon-carbon double bonds, respectively, were incorporated into Rhodobacter (Rb.) sphaeroides R-26.1 reaction centers. The extents of binding were found to be 95 +/- 5% for spheroidene, 65 +/- 5% for 3,4-dihydrospheroidene and 60 +/- 10% for 3,4,5,6-tetrahydrospheroidene. The dynamics of the triplet states of the primary donor and carotenoid were measured at room temperature by flash absorption spectroscopy. The carotenoid, spheroidene, was observed to quench the primary donor triplet state. The triplet state of spheroidene that was formed subsequently decayed to the ground state with a lifetime of 7.0 +/- 0.5 microseconds. The primary donor triplet lifetime in the Rb. sphaeroides R-26.1 reaction centers lacking carotenoids was 60 +/- 5 microseconds. Quenching of the primary donor triplet state by the carotenoid was not observed in the Rb. sphaeroides R-26.1 reaction centers containing 3,4-dihydrospheroidene nor in the R-26.1 reaction centers containing 3,4,5,6-tetrahydrospheroidene. Triplet-state electron paramagnetic resonance was also carried out on the samples. The experiments revealed carotenoid triple-state signals in the Rb. sphaeroides R-26.1 reaction centers incorporated with spheroidene, indicating that the primary donor triplet is quenched by the carotenoid. No carotenoid signals were observed from Rb. sphaeroides R-26.1 reaction centers incorporating 3,4-dihydrospheroidene nor in reaction centers incorporating 3,4,5,6-tetrahydrospheroidene. Circular dichroism, steady-state absorbance band shifts accompanying the primary photochemistry in the reaction center and singlet energy transfer from the carotenoid to the primary donor confirm that the carotenoids are bound in the reaction centers and interacting with the primary donor. These studies provide a systematic approach to exploring the effects of carotenoid structure and excited-state energy on triplet transfer between the primary donor and carotenoids in reaction centers from photosynthetic bacteria.
Asunto(s)
Carotenoides/química , Carotenoides/metabolismo , Proteínas del Complejo del Centro de Reacción Fotosintética/metabolismo , Rhodobacter sphaeroides/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Transferencia de Energía , Estructura Molecular , Proteínas del Complejo del Centro de Reacción Fotosintética/químicaRESUMEN
Several agents can alter biliary cholesterol secretion, critical for cholesterol excretion and gallstone formation. Although salicylate effects on bile formation and gallstones have been studied, biliary lipid secretion has not been measured during oral aspirin treatment. We examined whether oral acetylsalicylic acid affects bile lipid secretion. Three groups of young rats were fed chow for 3 wk. Two of the groups then received aspirin at either 1.67 or 3.33 g/kg diet for 4 d. Serum, hepatic, and bile lipids were measured, as were enzymes of cholesterol synthesis and esterification. With oral aspirin, bile cholesterol secretion increased by 42% and hepatic cholesteryl ester content decreased by 40%. Serum cholesterol and hepatic free cholesterol did not change. To evaluate mechanisms of the cholesterol hypersecretion, hypothyroid animals fed low-fat or fish oil diets and repleted with triiodothyronine were also studied. Aspirin stimulated cholesterol secretion to a degree similar to triiodothyronine. An additive response was seen in fish oil-fed rats. Aspirin did not appear to have a primary action on 3-hydroxy-3-methylglutaryl-CoA reductase or acyl CoA:cholesterol acyltransferase activities, and had no direct effect on esterification of cholesterol by isolated hepatocytes. Aspirin may directly increase cholesterol transport into bile or have cell membrane effects which alter cholesterol transport. It remains to be determined whether the observed alterations in bile cholesterol secretion are specific to the rat or also apply to humans.
Asunto(s)
Aspirina/farmacología , Bilis/metabolismo , Colesterol/metabolismo , Hígado/metabolismo , Administración Oral , Animales , Bilis/química , Ésteres del Colesterol/análisis , Dieta con Restricción de Grasas , Hidroximetilglutaril-CoA Reductasas/análisis , Hipotiroidismo/metabolismo , Masculino , Microsomas Hepáticos/enzimología , Ratas , Ratas Sprague-Dawley , Triyodotironina/farmacologíaRESUMEN
BACKGROUND: Male alcoholics hospitalized with actively bleeding esophageal varices were treated with sclerotherapy or sham sclerotherapy and the outcomes during the index hospitalization were compared. METHODS: The 87 patients were a subset of 253 patients enrolled in a prospective, randomized, single-blind, multicenter, controlled trial conducted in 12 VA medical centers. The patients (44 sclerotherapy, 43 sham therapy) were actively bleeding from esophageal varices at either randomization endoscopy (49) or follow-up endoscopy (38). Events and resource use during the index hospitalization were recorded. RESULTS: In 40 (91%) of the sclerotherapy and 26 (60%) of the sham therapy patients, bleeding was stopped during the endoscopy session (p < 0.001). During the hospitalization, 10 (25%) sclerotherapy and 21 (49%) sham therapy patients died (p = 0.04, relative risk 2.17, 95% CI [1.02, 4.61]); 9 sclerotherapy and 22 sham therapy patients rebled (p = 0.005). The median transfusion requirement was higher for sham therapy (8 vs 4 units, p = 0.001), the number of median ICU hours was greater (101 vs 55, p < 0.001), and more patients in this group required shunt surgery (6 vs 0, p = 0.01). CONCLUSION: Sclerotherapy, compared to no sclerotherapy, stops hemorrhage from actively bleeding esophageal varices and reduces use of resources. Sclerotherapy significantly increased hospital survival.
Asunto(s)
Várices Esofágicas y Gástricas/terapia , Hemorragia Gastrointestinal/terapia , Cirrosis Hepática Alcohólica/complicaciones , Escleroterapia , Alcoholismo/complicaciones , Endoscopía del Sistema Digestivo , Várices Esofágicas y Gástricas/complicaciones , Várices Esofágicas y Gástricas/diagnóstico , Estudios de Seguimiento , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/mortalidad , Mortalidad Hospitalaria , Hospitalización , Humanos , Cirrosis Hepática Alcohólica/diagnóstico , Cirrosis Hepática Alcohólica/mortalidad , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Escleroterapia/métodos , Método Simple Ciego , Resultado del TratamientoRESUMEN
As a step towards the structural analysis of the carotenoid spheroidene in the Rhodobacter sphaeroides reaction centre, we present the resonance Raman spectra of 14-2H, 15-2H, 15'-2H, 14'-2H, 14,15'-2H2 and 15-15'-2H2 spheroidenes in petroleum ether and, except for 14,15'-2H2 spheroidene, in the Rb. sphaeroides R26 reaction center (RC). Analysis of the spectral changes upon isotopic substitution allows a qualitative assignment of most of the vibrational bands to be made. For the all-trans spheroidenes in solution the resonance enhancement of the Raman bands is determined by the participation of carbon carbon stretching modes in the centre of the conjugated chain, the C9 to C15' region. For the RC-bound 15,15'-cis spheroidenes, enhancement is determined by the participation of carbon-carbon stretching modes in the centre of the molecule, the C13 to C13' region. Comparison of the spectra in solution and in the RC reveals evidence for an out-of-plane distortion of the RC-bound spheroidene in the central C14 to C14' region of the carotenoid. The characteristic 1240 cm-1 band in the spectrum of the RC-bound spheroidene has been assigned to a normal mode that contains the coupled C12-C13 and C13'-C12' stretch vibrations.
Asunto(s)
Carotenoides/química , Proteínas del Complejo del Centro de Reacción Fotosintética/química , Rhodobacter sphaeroides/química , Espectrometría Raman , Alcanos , Deuterio , Estructura Molecular , SolventesRESUMEN
OBJECTIVE: To confirm that spinal cord injured persons are susceptible to gallstones and to evaluate the role of gallbladder stasis as a risk factor. STUDY DESIGN: Twenty-nine subjects with chronic spinal cord injury underwent fasting ultrasonography to determine the incidence of gallstones and to quantitate gallbladder emptying response to a 20g fat liquid meal. Gallbladder emptying fraction was compared to that of healthy subjects studied concurrently. RESULTS: Gallstones or sludge were found in 6 spinal cord injured men, a minimal prevalence of 21%. Four additional subjects had prior cholecystectomy for stones, giving a potential maximal prevalence of 30%. Four of the 6 subjects had gallstone risk factors of diabetes, obesity, and/or family history. Gallbladder stasis was not apparent in chronic spinal cord injured subjects. Only 5 subjects had poor gallbladder emptying, and 4 of them had diabetes and/or obesity. CONCLUSIONS: The study confirms an increased prevalence of gallstones after spinal cord injury. However, gallbladder stasis did not appear to be etiologic, and most gallstones were associated with conventional risk factors. The results do not support a general policy of gallstone screening or prophylactic therapy after spinal cord injury.
Asunto(s)
Colelitiasis/diagnóstico por imagen , Colelitiasis/fisiopatología , Vesícula Biliar/diagnóstico por imagen , Traumatismos de la Médula Espinal/fisiopatología , Adulto , Femenino , Vesícula Biliar/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , UltrasonografíaRESUMEN
Obese persons are at risk for cholesterol gallstones because their bile is saturated with cholesterol. The risk increases during rapid weight loss by means of certain very-low-calorie diets or gastric bypass surgery. Gallstone risk factors during rapid weight loss include increased bile cholesterol saturation index and gallbladder stasis. Obese subjects were randomized to one of two low-calorie liquid diets for rapid weight loss: a 520-kcal diet with less than 2 g fat/d, and a 900-kcal diet with 30 g fat/d (including one 10-g fat meal to stimulate maximal gallbladder emptying). Bile and blood lipids, saturation index, leukocyte 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase activity, and ultrasonographic gallbladder emptying were measured repeatedly during dietary treatment. Both diets produced comparable weight loss of 22%. Bile cholesterol saturation index increased during both diets (26%), but fell to 15% below prediet level after weight loss. Compared with subjects' maximal gallbladder emptying fraction of 66%, the 520-kcal diet provided poor gallbladder emptying (35%), whereas the 10-g fat meal of the 900-kcal diet provided maximal emptying. Gallstones developed in four of six 520-kcal subjects and none of seven 900-kcal subjects (P = .021), an unanticipated difference that resulted in premature study termination for ethical reasons. Blood lipids and HMG CoA reductase activity in mononuclear leukocytes fell at week 8 during both diets, but recovered while weight was still being lost. The findings suggest that gallstone risk during rapid weight loss may be reduced by maintenance of gallbladder emptying with a small amount of dietary fat. Ultimately, weight loss reduced bile cholesterol saturation and improved highdensity lipoprotein (HDL) levels.