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4.
J Anesth ; 25(2): 241-6, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21225291

RESUMEN

PURPOSE: Sugammadex is a selective relaxant binding agent designed to encapsulate the aminosteroidal neuromuscular blocking agent rocuronium, thereby reversing its effect. Both sugammadex and the sugammadex-rocuronium complex are eliminated by the kidneys. This study investigated the effect of sugammadex on recovery of rocuronium-induced neuromuscular block in cats with clamped renal pedicles, as a model for acute renal failure. METHODS: Twelve male cats were divided into two groups and anesthetized with medetomidine, ketamine, and alpha-chloralose. The cats were intubated and ventilated with a mixture of oxygen and air. Neuromuscular monitoring was performed by single twitch monitoring. Rocuronium 0.5 mg/kg i.v. was administered. After spontaneous recovery from neuromuscular block, both renal pedicles were ligated. A second dose of rocuronium 0.5 mg/kg i.v. was given. One minute after disappearance of the twitches, in Group 1 placebo (0.9% saline) and in Group 2 sugammadex 5.0 mg/kg i.v. was administered. Onset time, duration of neuromuscular block, and time to recovery to 25, 50, 75, and 90% were determined. RESULTS: After renal pedicle ligation, sugammadex reversed rocuronium-induced neuromuscular block significantly faster than spontaneous recovery. Mean time (SEM) to 90% recovery of the twitch response was 4.7 (0.25) min (Group 2) versus 31.1 (5.0) min (Group 1) (p < 0.0001). No signs of recurrence of neuromuscular block were observed for 90 min after complete twitch restoration. Sugammadex caused no significant cardiovascular effects. CONCLUSION: Sugammadex rapidly and effectively reversed rocuronium-induced neuromuscular block in anesthetized cats, even when both renal pedicles were ligated and renal elimination of the drugs was no longer possible.


Asunto(s)
Androstanoles/farmacología , Bloqueo Neuromuscular , Fármacos Neuromusculares no Despolarizantes/farmacología , Circulación Renal , gamma-Ciclodextrinas/farmacología , Animales , Gatos , Frecuencia Cardíaca/efectos de los fármacos , Masculino , Rocuronio , Sugammadex
5.
Eur J Anaesthesiol ; 28(4): 265-72, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21157358

RESUMEN

BACKGROUND AND OBJECTIVE: 3-Desacetyl-vecuronium is an active metabolite of the neuromuscular blocking agent (NMBA) vecuronium, which might lead to residual paralysis after prolonged administration of vecuronium in critically ill patients with renal failure. This study investigated the ability of sugammadex to reverse 3-desacetyl-vecuronium-induced neuromuscular block (NMB) in the anaesthetised rhesus monkey. METHODS: Experiments were performed in anaesthetised female rhesus monkeys. After bolus intravenous injection of vecuronium (n = 8) or 3-desacetyl-vecuronium (n = 8) 10 µg kg(-1) (ED90), a continuous infusion of the same NMBA was started to maintain the first twitch of the train-of-four (TOF) at 10% of baseline value. The infusion was stopped and NMB recovered spontaneously. The procedure was repeated, but immediately after stopping the infusion, an intravenous bolus dose of sugammadex 0.5 or 1.0 mg kg(-1) was given. For each NMBA, four placebo experiments were performed, in which the second recovery from NMB was also spontaneous. For all experiments, time to recovery of the TOF ratio to 90% was retrieved. RESULTS: After administration of sugammadex for reversal of 3-desacetyl-vecuronium-induced NMB, recovery was significantly faster than spontaneous recovery. Mean time to recovery of TOF to 90% was 3.2 min (sugammadex 0.5 mg kg(-1)) and 2.6 min (1.0 mg kg(-1)), compared to spontaneous recovery (17.6 min). For vecuronium-induced NMB, mean time to recovery of TOF to 90% was 17.1 min (0.5 mg kg(-1)) and 4.6 min (1.0 mg kg(-1)), compared to spontaneous recovery (23.4 min). CONCLUSION: Sugammadex rapidly and effectively reversed 3-desacetyl-vecuronium-induced NMB in the rhesus monkey, at a lower dose than that needed to reverse vecuronium-induced NMB.


Asunto(s)
Unión Neuromuscular/efectos de los fármacos , Fármacos Neuromusculares no Despolarizantes/farmacología , Bromuro de Vecuronio/análogos & derivados , gamma-Ciclodextrinas/farmacología , Potenciales de Acción , Animales , Estimulación Eléctrica , Femenino , Infusiones Intravenosas , Inyecciones Intravenosas , Macaca mulatta , Fármacos Neuromusculares no Despolarizantes/administración & dosificación , Recuperación de la Función , Sugammadex , Factores de Tiempo , Bromuro de Vecuronio/administración & dosificación , Bromuro de Vecuronio/farmacología , gamma-Ciclodextrinas/administración & dosificación
6.
Eur J Pharmacol ; 641(2-3): 108-13, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-20538089

RESUMEN

A rat model of osteoarthritis was used to investigate the effect of pre-treatment with capsaicin on the symptoms of osteoarthritis induced by the injection of monosodium iodoacetate. This model mimics both histopathology and symptoms associated of human osteoarthritis. Injection of monosodium iodoacetate, an inhibitor of glycolysis, into the femorotibial joints of rodents promotes loss of articular trabecular bone and invokes pain symptoms similar to those noted in human osteoarthritis. Twenty rats were divided in two groups either receiving placebo or monosodium iodoacetate. Each group was subdivided in two groups either receiving pre-treatment with capsaicin two weeks before monosodium iodoacetate injection or not, resulting in four groups of five rats each. The impact of a single intra-articular administration of capsaicin (0.5%) on the generation of evoked mechanical pain (hind limb weight bearing, automated von Frey monofilament and RotaRod tests) and bone lesions (micro-CT scan radiographic analyses of bone structure) following monosodium iodoacetate-induced osteoarthritis in rats was determined. Evoked mechanical pain as monitored over a period of 4 weeks after monosodium iodoacetate injection was abolished in capsaicin pre-treated animals and pain values are comparable to those of capsaicin controls. Chronic joint pathological changes such as bone erosion and trabecular damage were significantly reduced by pre-treatment with a single administration of capsaicin. Decrease of bone volume was considerably ameliorated and trabecular connectivity was substantially better in capsaicin pre-treated animals. Capsaicin, an agonist activator of the vanilloid nociceptors (TRPV1), appears to be effective in protecting bone from arthritic damage. The present results support the hypothesis that capsaicin-sensitive sensory neurons contribute to bone lesions in the monosodium iodoacetate-induced osteoarthritis rat model.


Asunto(s)
Huesos/patología , Capsaicina/farmacología , Osteoartritis/patología , Dolor/inducido químicamente , Animales , Capsaicina/efectos adversos , Capsaicina/uso terapéutico , Modelos Animales de Enfermedad , Miembro Posterior/patología , Humanos , Inyecciones Intraarticulares , Yodoacetatos , Nociceptores/patología , Osteoartritis/inducido químicamente , Osteoartritis/tratamiento farmacológico , Dolor/tratamiento farmacológico , Dolor/patología , Rótula/patología , Ratas , Ratas Sprague-Dawley , Células Receptoras Sensoriales/fisiología , Soporte de Peso/fisiología
7.
Anesth Analg ; 109(6): 1799-803, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19923505

RESUMEN

BACKGROUND: Intravenous opioid therapy is frequently used for postoperative pain management in children after orthopedic surgery but causes side effects such as respiratory depression, vomiting, sedation, and urinary retention. To investigate whether a continuous incisional fascia iliaca compartment (FIC) block provides more effective postoperative pain relief with fewer side effects than IV morphine, we performed a prospective, double-blind, randomized study to compare both techniques. METHODS: Thirty children (ASA physical status I-II) aged 3 mo to 6 yr undergoing a pelvic osteotomy were included in the study. The children were randomized for either morphine IV and placebo (saline) via a FIC catheter (Group M) or placebo (saline) IV and ropivacaine via a FIC catheter (Group R). All patients received general anesthesia using inhaled sevoflurane and IV fentanyl. Perioperatively, a FIC catheter was placed by the surgeon. All patients received either a bolus dose of morphine IV (Group M) or ropivacaine 0.75% via the FIC catheter (Group R) at the end of surgery. Postoperatively, Group M received morphine IV 20 microg x kg(-1) x h(-1) and Group R ropivacaine 0.2% 0.1 mL x kg(-1) x h(-1) via the FIC catheter. In both groups, saline was administered along the other route. All children were assessed for pain, sedation, time until first oral intake, and adverse effects for 48 h postoperatively. During this period, all children had a urinary catheter. RESULTS: The study was completed by 28 children. In the anesthetic recovery room, children in Group M had significantly higher pain scores. These children were also significantly more sedated during the study period. The incidence of vomiting did not differ between the groups; however, children in Group R had first oral intake significantly earlier than Group M. A local retrospective study revealed an incidence of urinary retention of 4.7% in the ropivacaine-treated patients and 39% in the morphine-treated patients. CONCLUSIONS: Continuous incisional FIC block provides excellent postoperative pain relief, less sedation, and better return of appetite than morphine IV after pelvic osteotomy in children.


Asunto(s)
Amidas/administración & dosificación , Analgésicos Opioides/administración & dosificación , Anestésicos Locales/administración & dosificación , Fascia/inervación , Morfina/administración & dosificación , Bloqueo Nervioso/métodos , Osteotomía/efectos adversos , Dolor Postoperatorio/prevención & control , Huesos Pélvicos/cirugía , Analgésicos Opioides/efectos adversos , Periodo de Recuperación de la Anestesia , Apetito/efectos de los fármacos , Niño , Preescolar , Método Doble Ciego , Humanos , Lactante , Infusiones Intravenosas , Morfina/efectos adversos , Bloqueo Nervioso/efectos adversos , Dimensión del Dolor , Dolor Postoperatorio/etiología , Estudios Prospectivos , Ropivacaína , Sueño/efectos de los fármacos , Resultado del Tratamiento , Vómitos/inducido químicamente
8.
Clin Rehabil ; 23(12): 1059-66, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19906762

RESUMEN

OBJECTIVE: To determine if treatment of longstanding complex regional pain syndrome type 1, focusing on functional improvement only while neglecting pain, results in clinical improvement of this syndrome. DESIGN: Prospective description of a case series of 106 patients. SETTING: Outpatient clinic for rehabilitation. INTERVENTIONS: Physical therapy of the affected limb directed at a functional improvement only while neglecting the pain, was performed following an extensive explanation. Normal use of the limb between the treatments was encouraged despite pain. A maximum of five of these sessions were performed in three months. MEASURES: Radboud Skills Test was used to monitor functional improvement of the arms. Speed and walking distance was used as the measure of outcome for the legs. RESULTS: The function of the affected arm or leg improved in 95 patients. Full functional recovery was experienced in 49 (46%) of them. A reduction in pain presented in 75 patients. In 23 patients functional recovery was reached despite an increase in pain. Four patients stopped early due to pain increase. CONCLUSIONS: Our results suggest that 'pain exposure physical therapy' is effective and safe for patients who are unresponsive to accepted standard therapies. Avoiding the use of a limb due to pain will result in loss of function. Forced usage of limbs restores the function, reverses these adaptive processes and leads to regain of control by practice with a reduction of pain in most cases.


Asunto(s)
Terapia por Ejercicio , Distrofia Simpática Refleja/terapia , Adolescente , Adulto , Anciano , Estudios de Factibilidad , Humanos , Persona de Mediana Edad , Dimensión del Dolor , Estudios Prospectivos , Recuperación de la Función , Distrofia Simpática Refleja/fisiopatología , Adulto Joven
9.
Anesth Analg ; 109(5): 1659-65, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19843805

RESUMEN

BACKGROUND: Fos expression in the lumbar spinal cord, resulting from a noxious electrical stimulus at the hindpaw, is hypothesized to originate from three sources: direct sensory input of the noxious stimulus, local interactions in the spinal cord, and input of modulating signals from supraspinal regions. Our aim in this study was to discriminate among these sources by eliminating the supraspinal input. METHODS: Therefore, a spinal block was administered in male Wistar rats by administering a local anesthetic (bupivacaine) through an intrathecal catheter at the mid-thoracic level. This thoracic spinal block completely suppressed the noxious stimulation-induced withdrawal reflex that is normally elicited by electrical stimulus. Fos immunoreactivity (Fos-IR) was quantified in all laminae of the L4 segment of the spinal cord. RESULTS: Noxious stimulation resulted in a general and strong increase in Fos-IR in the ipsilateral dorsal horn, mainly in Laminae I, II, and V. Thoracic spinal block caused a remarkable increase in the amount of Fos-IR in Lamina V, but had no significant effect on the Fos-IR in Laminae I and II. CONCLUSIONS: The increase in Fos-IR in Lamina V may have resulted from the interruption of a pain-modulating descending mechanism from the brain. A known modulating descending mechanism is the serotonergic system, controlled by the periaqueductal gray. This system inhibits the neurons in the superficial laminae. Another nonserotonergic system originates in the anterior pretectal nucleus. The latter facilitates neurons in the superficial laminae, while neurons in Lamina V are inhibited. We conclude that both systems are probably involved in the observed effects of the peripheral noxious stimulation given in the present model.


Asunto(s)
Extremidades/inervación , Bloqueo Nervioso/métodos , Dolor/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Médula Espinal/metabolismo , Anestésicos Locales/administración & dosificación , Animales , Bupivacaína/administración & dosificación , Estimulación Eléctrica , Inyecciones Espinales , Vértebras Lumbares , Masculino , Inhibición Neural , Dolor/fisiopatología , Dolor/prevención & control , Ratas , Ratas Wistar , Reflejo Anormal , Médula Espinal/fisiopatología , Vértebras Torácicas , Regulación hacia Arriba
10.
Anesthesiology ; 111(4): 836-43, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19741489

RESUMEN

BACKGROUND: Mechanical ventilation (MV) can induce lung injury. Proinflammatory cytokines have been shown to play an important role in the development of ventilator-induced lung injury. Previously, the authors have shown a role for Toll-like receptor 4 signaling. The current study aims to investigate the role of Toll/interleukin-1 receptor domain-containing adapter-inducing interferon-beta (TRIF), a protein downstream of Toll-like receptors, in the development of the inflammatory response after MV in healthy mice. METHODS: Wild-type C57BL6 and TRIF mutant mice were mechanically ventilated for 4 h. Lung tissue and plasma was used to investigate changes in cytokine profile, leukocyte influx, and nuclear factor-kappaB activity. In addition, experiments were performed to assess the role of TRIF in changes in cardiopulmonary physiology after MV. RESULTS: MV significantly increased messenger RNA expression of interleukin (IL)-1beta in wild-type mice, but not in TRIF mutant mice. In lung homogenates, MV increased levels of IL-1alpha, IL-1beta, and keratinocyte-derived chemokine in wild-type mice. In contrast, in TRIF mutant mice, only a minor increase in IL-1beta and keratinocyte-derived chemokine was found after MV. Nuclear factor-kappaB activity after MV was significantly lower in TRIF mutant mice compared with wild-type mice. In plasma, MV increased levels of IL-6 and keratinocyte-derived chemokine. In TRIF mutant mice, no increase of IL-6 was found after MV, and the increase in keratinocyte-derived chemokine appeared less pronounced. TRIF deletion did not affect cardiopulmonary physiology after MV. CONCLUSIONS: The current study supports a prominent role for TRIF in the development of the pulmonary and systemic inflammatory response after MV.


Asunto(s)
Proteínas Adaptadoras del Transporte Vesicular/genética , Proteínas Adaptadoras del Transporte Vesicular/fisiología , Inflamación/genética , Inflamación/fisiopatología , Respiración Artificial , Lesión Pulmonar Inducida por Ventilación Mecánica/genética , Lesión Pulmonar Inducida por Ventilación Mecánica/fisiopatología , Animales , Citocinas/metabolismo , Inflamación/metabolismo , Lipopolisacáridos/toxicidad , Pulmón/metabolismo , Pulmón/patología , Ratones , Ratones Endogámicos C57BL , FN-kappa B/genética , FN-kappa B/fisiología , Oligonucleótidos/genética , ARN Mensajero/análisis , ARN Mensajero/biosíntesis , Lesión Pulmonar Inducida por Ventilación Mecánica/metabolismo
11.
NMR Biomed ; 22(4): 414-8, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19003937

RESUMEN

Isoflurane (ISO) can be a valuable alternative for alpha-chloralose (ACL) anesthesia in functional MRI (fMRI) studies. Therefore, we compared the efficacy of the blood oxygen level dependent (BOLD) effect in fMRI studies during ISO and ACL anesthesia sequentially in the same animals. After non-invasive instrumentation for ventilation and monitoring, series of T2* weighted MR images were acquired during forepaw stimulation, first under ISO, then followed by ACL anesthesia. The results demonstrated that ISO and ACL were both suitable to perform this fMRI experiment. The center of activation was at the same stereotactic position for both anesthetics and matched the primary somatosensory cortex (S1). Under the applied conditions, the BOLD response during ISO anesthesia declined in magnitude during the first stimulation period, as compared to ACL. From this study, we conclude that since ISO has several positive properties in comparison to ACL, including fast pharmacokinetics and suitability for repeated measurements, it is a valuable alternative for anesthesia in fMRI studies of rats.


Asunto(s)
Anestesia , Cloralosa/administración & dosificación , Cloralosa/farmacología , Isoflurano/administración & dosificación , Isoflurano/farmacología , Animales , Estimulación Eléctrica , Imagen por Resonancia Magnética , Masculino , Modelos Animales , Oxígeno/sangre , Ratas , Ratas Wistar , Técnicas Estereotáxicas
12.
Anesthesiology ; 109(3): 465-72, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18719444

RESUMEN

BACKGROUND: Mechanical ventilation (MV) can induce ventilator-induced lung injury. A role for proinflammatory pathways has been proposed. The current studies analyzed the roles of Toll-like receptor (TLR) 4 and TLR2 involvement in the inflammatory response after MV in the healthy lung. METHODS: Wild-type (WT) C57BL6, TLR4 knockout (KO), and TLR2 KO mice were mechanically ventilated for 4 h. Bronchoalveolar lavage fluid was analyzed for presence of endogenous ligands. Lung homogenates were used to investigate changes in TLR4 and TLR2 expression. Cytokines were measured in lung homogenate and plasma, and leukocytes were counted in lung tissue. RESULTS: MV significantly increased endogenous ligands for TLR4 in bronchoalveolar lavage fluid and relative messenger RNA expression of TLR4 and TLR2 in lung tissue. In lung homogenates, MV in WT mice increased levels of keratinocyte-derived chemokine, interleukin (IL)-1alpha, and IL-1beta. In TLR4 KO mice, MV increased IL-1alpha but not IL-1beta, and the increase in keratinocyte-derived chemokine was less pronounced. In plasma, MV in WT mice increased levels of IL-6, keratinocyte-derived chemokine, and tumor necrosis factor alpha. In TLR4 KO mice, MV did not increase levels of IL-6 or tumor necrosis factor alpha, and the response of keratinocyte-derived chemokine was less pronounced. MV in TLR2 KO mice did not result in different cytokine levels compared with WT mice. In WT and TLR2 KO mice, but not in TLR4 KO mice, MV increased the number of pulmonary leukocytes. CONCLUSIONS: The current study supports a role for TLR4 in the inflammatory reaction after short-term MV in healthy lungs. Increasing the understanding of the innate immune response to MV may lead to future treatment advances in ventilator-induced lung injury, in which TLR4 may serve as a therapeutic target.


Asunto(s)
Inflamación/etiología , Respiración Artificial/efectos adversos , Receptor Toll-Like 4/metabolismo , Animales , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/inmunología , Recuento de Células , Células Cultivadas , Quimiocinas/sangre , Quimiocinas/inmunología , Citocinas/sangre , Citocinas/inmunología , Citocinas/metabolismo , Inflamación/inmunología , Interleucinas/inmunología , Interleucinas/metabolismo , Leucocitos/inmunología , Ligandos , Pulmón/inmunología , Pulmón/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , ARN Mensajero/inmunología , ARN Mensajero/metabolismo , Valores de Referencia , Respiración Artificial/métodos , Volumen de Ventilación Pulmonar , Receptor Toll-Like 2/genética , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/genética , Factor de Necrosis Tumoral alfa/sangre , Factor de Necrosis Tumoral alfa/inmunología
13.
Crit Care Med ; 36(8): 2403-6, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18596626

RESUMEN

BACKGROUND: Mechanical ventilation with small tidal volumes reduces the development of ventilator-induced lung injury and mortality, but may increase PaCO2. It is not clear whether the beneficial effect of a lung-protective strategy results from reduced ventilation pressures/tidal volumes or is mediated by the effects of hypercapnic acidosis on the inflammatory response involved in the pathogenesis of ventilator-induced lung injury. OBJECTIVE: To analyze whether hypercapnic acidosis affects lung tissue cytokine levels and leukocyte influx in healthy ventilated mice. STUDY DESIGN: Analysis of lung tissue and plasma concentrations of interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, IL-6, IL-10, and keratocyte-derived chemokine after 2 hrs of mechanical ventilation (V(t) 8 mL/kg, positive end-expiratory pressure 4 cm H2O) with 0.06% CO2 (room air), 2% CO2, or 4% CO2. SUBJECTS: Healthy C57BL6 mice (n = 40). MEASUREMENTS/RESULTS: PaCO2 and pH were within normal range when ventilated with 0.06% CO2 and significantly changed with 2% and 4% CO2: (mean +/- SD) pH 7.23 +/- 0.06 and 7.15 +/- 0.04, PaCO2 7.9 +/- 1.4 and 10.8 +/- 0.7 kPa, respectively (p < 0.005). Blood pressure remained within normal limits in all animals. Quantitative microscopic analysis showed a 4.7 +/- 3.7-fold increase (p < 0.01) in pulmonary leukocyte influx in normocapnic ventilated animals and a significant reduction in leukocyte influx of 57 +/- 32% (p < 0.01) and 67 +/- 22% (p < 0.01) when ventilated with 2% and 4% CO2, respectively. Normocapnic ventilation induced a significant elevation of lung tissue IL-1beta (1516 +/- 119 ng/mL), TNF-alpha (344 +/- 88 ng/mL), IL-6 (6310 +/- 807 ng/mL), IL-10 (995 +/- 152 ng/mL), and keratocyte-derived chemokine (36,966 +/- 15,294 ng/mL) (all p-values <0.01). Hypercapnic acidosis with 2% respectively 4% CO2 significantly attenuated this increase with 25 +/- 32% and 54 +/- 32% (IL-1beta, p < 0.01); 17 +/- 36% and 58 +/- 33% (TNF-alpha, p < 0.02); 22 +/- 34% and 89 +/- 6% (IL-6, p < 0.01); 20 +/- 31% and 67 +/- 17% (IL-10, p < 0.01) and 16 +/- 44% and 45 +/- 30% (keratocyte-derived chemokine, p = 0.07). CONCLUSION: Hypercapnic acidosis attenuates the mechanical ventilation-induced immune response independent from reduced tidal volumes/pressures and may protect the lung from ventilator induced lung injury.


Asunto(s)
Acidosis/metabolismo , Citocinas/metabolismo , Leucocitos/metabolismo , Pulmón/metabolismo , Acidosis/inmunología , Animales , Análisis de los Gases de la Sangre , Ratones , Ratones Endogámicos C57BL , Respiración Artificial/efectos adversos , Volumen de Ventilación Pulmonar
14.
Anesth Analg ; 106(4): 1303-8, table of contents, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18349210

RESUMEN

BACKGROUND: Although our understanding of nociceptive processing during anesthesia has increased greatly over the last decade, many patients still experience hyperalgesia and acute pain postoperatively. The noxious-induced withdrawal reflex (NIWR) model is specifically designed and validated to quantitatively study the reaction on painful, multimodal stimuli in animals under anesthetic conditions. Since the anesthetic mechanisms differ between inhaled anesthetics and opioids, we evaluated the differential effects of isoflurane and fentanyl on c-fos expression at the lumbar level as a measure of nociceptive information transfer during general anesthesia. METHODS: The experimental setup consisted of a randomized block design with four experimental groups: two light (3/4) minimum alveolar concentration (MAC) isoflurane anesthesia groups (unstimulated/NIWR-stimulated) and two NIWR-stimulated surgical anesthesia groups (1(1/2) MAC isoflurane anesthesia and (3/4) MAC isoflurane anesthesia combined with fentanyl 400-600 microg x kg(-1) x h(-1)). After 2 h of intermittent electrical stimulation of the hind paw of the rat, the number of Fos immunoreactive (Fos-IR) neurons in the dorsal horn was measured quantitatively. RESULTS: The main suppressive effects on lumbar c-fos expression of isoflurane were observed in the superficial lamina II (P = 0.02), whereas fentanyl showed the strongest effects in lamina V (P = 0.05). CONCLUSIONS: This study demonstrates that the NIWR model combined with spinal Fos-immunoreactivity is a suitable and useful model for evaluating the differential effects of inhaled anesthetics and opioids on nociceptive information transfer during general anesthesia.


Asunto(s)
Fentanilo/uso terapéutico , Isoflurano/uso terapéutico , Dolor/fisiopatología , Proteínas Proto-Oncogénicas c-fos/metabolismo , Médula Espinal/fisiología , Analgésicos/uso terapéutico , Anestesia , Animales , Quimioterapia Combinada , Estimulación Eléctrica , Vértebras Lumbares , Masculino , Dolor/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-fos/efectos de los fármacos , Ratas , Ratas Wistar , Médula Espinal/efectos de los fármacos
16.
Anesthesiology ; 107(3): 419-26, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17721244

RESUMEN

BACKGROUND: Mechanical ventilation (MV) may activate the innate immune system, causing the release of cytokines. The resulting proinflammatory state is a risk factor for ventilator-induced lung injury. Cytokine increase results from direct cellular injury but may also result from cyclic stretch alone as demonstrated in vitro: mechanotransduction. To study mechanotransduction in vivo, the authors used an animal MV model with clinically relevant ventilator settings, avoiding alveolar damage. METHODS: Healthy C57BL6 mice (n = 82) were ventilated (tidal volume, 8 ml/kg; positive end-expiratory pressure, 4 cm H2O; fraction of inspired oxygen, 0.4) for 30, 60, 120, and 240 min. Assigned animals were allowed to recover for 2 days after MV. Both pulmonary tissue and plasma interleukin (IL)-1alpha, IL-1beta, tumor necrosis factor alpha, IL-6, IL-10, and keratinocyte-derived chemokine levels were measured. Histopathologic appearance of lung tissue was analyzed by light microscopy and electron microscopy. RESULTS: In lung tissue, all measured cytokines and keratinocyte-derived chemokine levels increased progressively with MV duration. Light microscopy showed increased leukocyte influx but no signs of alveolar leakage or albumin deposition. Electron microscopy revealed intact epithelial cell and basement membranes with sporadically minimal signs of partial endothelial detachment. In plasma, increased levels of IL-1alpha, tumor necrosis factor alpha, IL-6, and keratinocyte-derived chemokine were measured after MV. In the recovery animals, cytokine levels had normalized and no histologic alterations could be found. CONCLUSIONS: Mechanical ventilation induces reversible cytokine increase and leukocyte influx with preserved tissue integrity. This model offers opportunities to study the pathophysiologic mechanisms behind ventilator-induced lung injury and the contribution of MV to the "multiple-hit" concept.


Asunto(s)
Citocinas/metabolismo , Pulmón/metabolismo , Pulmón/fisiopatología , Alveolos Pulmonares/fisiopatología , Respiración Artificial/efectos adversos , Animales , Análisis de los Gases de la Sangre/métodos , Presión Sanguínea , Quimiocinas/sangre , Citocinas/biosíntesis , Interleucinas/sangre , Queratinocitos , Leucocitos/metabolismo , Pulmón/ultraestructura , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica/métodos , Modelos Animales , Valores de Referencia , Respiración Artificial/métodos , Factores de Tiempo , Factor de Necrosis Tumoral alfa/sangre
17.
Neuropsychiatr Dis Treat ; 3(5): 539-44, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-19300584

RESUMEN

Steroidal neuromuscular blocking agents (NMBAs), such as rocuronium, are widely used in clinical anesthesia and emergency medicine to facilitate endotracheal intubation and artificial ventilation and to allow surgical access to body cavities. Reversal of neuromuscular blockade is important for the acceleration of patient recovery and prevention of postoperative residual neuromuscular blockade and reduces the incidence of severe morbidity and mortality associated with anesthesia management. Sugammadex is the first selective relaxant binding agent (SRBA) and has been designed to reverse the steroidal neuromuscular blocking drug rocuronium. Encapsulation of the rocuronium molecule by sugammadex results in a rapid decrease in free rocuronium in the plasma and subsequently at the nicotinic receptor at the motor endplate. After encapsulation, rocuronium is not available to bind to the nicotinic receptor in the neuromuscular junction. This promotes the liberation of acetylcholine receptors, and muscle activity reappears. This new concept of reversal of neuromuscular block induced by rocuronium (or vecuronium) led to impressive results in animal and phase 1 and 2 studies. Sugammadex is currently in phase 3 clinical studies and may be commercially available by 2008.

18.
Anesthesiology ; 104(4): 718-23, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16571967

RESUMEN

BACKGROUND: Reversal of neuromuscular blockade can be accomplished by chemical encapsulation of rocuronium by sugammadex, a synthetic gamma-cyclodextrin derivative. The current study determined the feasibility of reversal of rocuronium-induced profound neuromuscular blockade with sugammadex in the anesthetized rhesus monkey using train-of-four stimulation. METHODS: Four female rhesus monkeys each underwent three experiments. In each experiment, first, a 100-microg/kg dose of rocuronium was injected and spontaneous recovery was monitored. After full recovery, a 500-microg/kg dose of rocuronium was injected. Up to this point, all three experiments in a single monkey were identical. One minute after this rocuronium injection, either one of the two tested dosages of sugammadex (1.0 or 2.5 mg/kg) was injected or saline was injected. RESULTS: Injection of 100 microg/kg rocuronium resulted in a mean neuromuscular blockade of 93.0% (SD = 4%), and profound blockade was achieved by injection of 500 microg/kg. In all experiments, a 100% neuromuscular blockade was achieved at this dose. After injection of the high rocuronium dose, the 90% recovery of the train-of-four ratio took 28 min (SD = 7 min) after saline, 26 min (SD = 9.5 min) after 1 mg/kg sugammadex, and 8 min (SD = 3.6 min) after 2.5 mg/kg sugammadex. Signs of residual blockade or recurarization were not observed. Injection of sugammadex had no significant effects on blood pressure or heart rate. CONCLUSIONS: Chemical encapsulation of rocuronium by sugammadex is a new therapeutic mechanism allowing effective and rapid reversal of profound neuromuscular blockade induced by rocuronium in anesthetized rhesus monkeys.


Asunto(s)
Androstanoles/antagonistas & inhibidores , Bloqueo Neuromuscular , Fármacos Neuromusculares no Despolarizantes/antagonistas & inhibidores , gamma-Ciclodextrinas/farmacología , Androstanoles/farmacología , Animales , Presión Sanguínea/efectos de los fármacos , Inhibidores de la Colinesterasa/farmacología , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Macaca mulatta , Rocuronio , Sugammadex
19.
J Headache Pain ; 6(1): 24-9, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16362188

RESUMEN

The results obtained by percutaneous cervical cordotomy (PCC) were analysed in 43 terminally ill cancer patients treated in our institution from 1998 to 2001. We wished to determine whether there is still a place for PCC in the actual clinical situation with its wide choice of pain therapies. All patients had severe unilateral pain due to cancer, resistant to opioids and co-analgesics. Following PCC, mean pain intensity was reduced from Numeric Rating Scale (NRS) 7.2 to 1.1. At the end of life, pain had increased to NRS 2.9. Initially following PCC a good result (NRS<3) was obtained in 95% of patients. At the end of life, a good result was still present in 69% of patients. Mean duration of survival after the intervention was 118 days (2-1460). In general, complications were mild and mostly subsided within 3-4 days. There was one case of partial paresis of the ipsilateral leg. PCC remains a valuable treatment in patients with treatment-resistant cancer pain and still deserves a place in the treatment of terminal cancer patients with severe unilateral neuropathic or incidence pain.


Asunto(s)
Cordotomía/estadística & datos numéricos , Neoplasias/complicaciones , Dolor Intratable/cirugía , Médula Espinal/cirugía , Tractos Espinotalámicos/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Analgésicos/uso terapéutico , Vértebras Cervicales/cirugía , Cordotomía/tendencias , Resistencia a Medicamentos/fisiología , Femenino , Humanos , Inyecciones Espinales/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Dolor Intratable/etiología , Dolor Intratable/fisiopatología , Satisfacción del Paciente/estadística & datos numéricos , Complicaciones Posoperatorias/etiología , Calidad de Vida/psicología , Estudios Retrospectivos , Médula Espinal/anatomía & histología , Médula Espinal/fisiología , Tractos Espinotalámicos/anatomía & histología , Tractos Espinotalámicos/fisiología , Enfermo Terminal , Insuficiencia del Tratamiento , Resultado del Tratamiento
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