RESUMO
BACKGROUND: Conventional laparoscopic cholecystectomy (CLC) with carbon dioxide pneumoperitoneum may cause major cardiovascular changes. The aim of this study was to evaluate the effect of carbon dioxide pneumoperitoneum and positional changes on haemodynamics and cardiac function in patients assigned randomly to CLC or gasless laparoscopic cholecystectomy (GLC). METHODS: Fifty patients with American Society of Anesthesiologists physical status I and II were randomly allocated to CLC (28 patients) or GLC (22). Left ventricular end-diastolic and end-systolic diameters, fractional shortening and cardiac output were determined by transoesophageal echocardiography. Measurements were performed before (phase 1) and 10 and 30 min (phases 2 and 3 respectively) after pneumoperitoneum or abdominal wall traction, and after desufflation or release of abdominal wall traction (phase 4) in supine, Trendelenburg and reverse Trendelenburg positions. RESULTS: Mean diastolic diameter, systolic diameter, mean arterial pressure and heart rate were significantly higher, and fractional shortening was significantly lower, with carbon dioxide pneumoperitoneum than with the gasless procedure during phases 2 and 3. There were no significant differences in cardiac output between the two groups. CONCLUSION: Carbon dioxide pneumoperitoneum was associated with increased preload and afterload in patients undergoing laparoscopic cholecystecomy. It also decreased heart performance (fractional shortening), but did not affect cardiac output.
Assuntos
Colecistectomia Laparoscópica/métodos , Coração/fisiologia , Pneumoperitônio Artificial/métodos , Adulto , Idoso , Análise de Variância , Pressão Sanguínea/fisiologia , Dióxido de Carbono , Débito Cardíaco/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Função Ventricular Esquerda/fisiologiaRESUMO
UNLABELLED: The objective was to identify risk factors for shunt infections, and establish the rate of infection for shunt procedures carried out under standardized conditions in a well-defined population. All (407) paediatric shunt operations (primary and revisions) performed within a total population of 630000 inhabitants between January 1, 1986 and December 31, 1996, were analysed retrospectively. 11 shunt infections were diagnosed in 10 patients, giving an overall infection rate of 2.7% per procedure and 6.2% per patient. Infections were significantly correlated with age, type of operation, and a etiology of hydrocephalus. Thus, infections occurred more frequently during the first 6 months of life, more often following primary shunt insertions compared with revisions, and children with myelomeningocele had a higher infection risk than children with hydrocephalus due to other causes. There was a highly significant male preponderance in the patient material. CONCLUSION: The overall infection rate was relatively low. The risk factors for shunt infections appear to relate to epidemiological characteristics rather than to surgical factors.
Assuntos
Candidíase/etiologia , Derivações do Líquido Cefalorraquidiano/efeitos adversos , Hidrocefalia/cirurgia , Infecções Estafilocócicas/etiologia , Infecção da Ferida Cirúrgica/etiologia , Adolescente , Fatores Etários , Candidíase/epidemiologia , Derivações do Líquido Cefalorraquidiano/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Humanos , Hidrocefalia/epidemiologia , Lactente , Recém-Nascido , Masculino , Noruega/epidemiologia , Vigilância da População , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Infecções Estafilocócicas/epidemiologia , Infecção da Ferida Cirúrgica/epidemiologiaRESUMO
BACKGROUND: The recent rapid progress in pain research is due in large part to advances in genetics and cell and molecular biology. We now know that chronic pain (hypersensitivity due to inflammation or nerve injury) and acute nociceptive pain are different and must be treated accordingly. We will continue to reveal sophisticated mechanisms underlying different kinds of pain that can be targeted to inhibit nociceptive transmission and produce analgesia. METHODS: This review is based upon literature collected through the authors' own reading and through PubMed searches. New hopes for future pain treatments are discussed. Further, the impact of genetic factors on pain sensitivity and pain modulation are discussed, and conceivable therapeutic approaches based on genetic techniques are mentioned. RESULT: At the level of the peripheral nerve, many novel targets have recently been identified: the tetrodotoxin-resistant sodium channel, the vanilloid receptor and different calcium channels are very interesting. In the spinal cord, different approaches can be used: to either block excitatory input or to increase inhibitory control or to do both at the same time. The mechanisms for hypersensitivity are being identified and offer multiple possible targets for novel analgesics. INTERPRETATION: Many interesting targets for analgetics has emerged during that last few years, lending great hope for new and better (i.e. with less side effects) analgesic drugs in the future.
Assuntos
Analgesia/tendências , Analgésicos , Manejo da Dor , Analgesia/métodos , Analgésicos/administração & dosagem , Analgésicos/farmacocinética , Animais , Terapia Genética , Humanos , Modelos Neurológicos , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/genética , Plasticidade Neuronal/fisiologia , Nociceptores/efeitos dos fármacos , Nociceptores/fisiologia , Dor/tratamento farmacológico , Dor/genética , Dor/fisiopatologia , Sistema Nervoso Periférico/efeitos dos fármacos , Sistema Nervoso Periférico/fisiologia , Farmacogenética , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/fisiologia , Receptores Opioides/efeitos dos fármacos , Receptores Opioides/genética , Receptores Opioides/fisiologia , Pesquisa , Medula Espinal/efeitos dos fármacos , Medula Espinal/fisiologia , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/genética , Transmissão Sináptica/fisiologiaRESUMO
Normal pressure hydrocephalus (NPH) is an important diagnosis to keep in mind, i.e. the possibility that NPH and not a neurodegenerative disease causes the patient's symptoms with ataxia, urinary incontinence and dementia. Clinical improvement, sometimes a complete reversal of the symptoms, may be seen after a simple surgical procedure. This prospective study was performed by testing eight consecutively shunted patients with a walking test and a cognitive test battery pre- and postoperatively. Improvement 3-4 months after the shunting procedure suggests that NPH was present in six of eight patients. Walking ability was improved after surgery, also in patients with severe dementia. Severe dementia caused by NPH is hardly reversible, though cognitive tests may indicate some improvement. However, early surgical treatment of NPH in patients not suffering from a dementia according to the Mini Mental Status Test may bring improvement in some cognitive functions. Patients with both clinical and radiological signs of normal pressure hydrocephalus should be offered a shunting procedure.
Assuntos
Hidrocefalia de Pressão Normal/cirurgia , Idoso , Cognição , Demência/diagnóstico , Demência/cirurgia , Diagnóstico Diferencial , Humanos , Hidrocefalia de Pressão Normal/diagnóstico , Hidrocefalia de Pressão Normal/psicologia , Ilustração Médica , Testes Neuropsicológicos , Estudos Prospectivos , Tomografia Computadorizada por Raios X , Derivação Ventriculoperitoneal , CaminhadaRESUMO
BACKGROUND: Carbon dioxide pneumoperitoneum may be an important pathophysiological factor stimulating the coagulation system during conventional laparoscopic cholecystectomy. The aim of this study was to test the hypothesis that gasless laparoscopy produces smaller changes in the coagulation and fibrinolytic system than carbon dioxide pneumoperitoneum in patients undergoing laparoscopic cholecystectomy. METHODS: Fifty patients were allocated randomly to conventional (n = 26) or gasless (n = 24) laparoscopic cholecystectomy. Blood samples were obtained on admission, after induction of anaesthesia, after insufflation or traction, 30 min after introduction of the laparoscope, 10 min after exsufflation of carbon dioxide or traction, 4 h after extubation and 24 h after operation. RESULTS: The two groups were comparable with respect to age, sex, body mass index and duration of operation. Plasma levels of prothrombin fragment 1 and 2 (F1 + 2), soluble fibrin and D-dimer did not differ between the two groups. F1 + 2 levels varied significantly in both groups during and after operation (P < 0.001). Soluble fibrin and D-dimer levels did not change during operation in either group, but after operation the levels increased significantly in both groups (P < 0.001). CONCLUSION: Carbon dioxide pneumoperitoneum does not enhance the activation of coagulation and fibrinolysis associated with laparoscopic cholecystectomy. The coagulation and fibrinolytic systems are activated during and after gasless as well as conventional laparoscopic cholecystectomy.
Assuntos
Coagulação Sanguínea/fisiologia , Colecistectomia Laparoscópica/métodos , Fibrinólise/fisiologia , Pneumoperitônio Artificial/métodos , Adulto , Idoso , Feminino , Fibrina/análise , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Humanos , Masculino , Pessoa de Meia-Idade , Protrombina/análiseRESUMO
The positive CO2 pneumoperitoneum needed to create the working space for laparoscopic surgery induces cardiovascular, neuroendocrine, and renal changes. Concern about these pathophysiologic changes has led to the introduction of a gasless technique. Fifty consecutive patients with symptomatic gallstones were randomized to conventional (CLC) or gasless laparoscopic cholecystectomy (GLC), with special reference to overall patient satisfaction, technical difficulties, duration of surgery, postoperative pain, and recovery. The overall exposure of the operative field was extremely poor in the GLC group, whereas the duration of surgery, steps involved in the cholecystectomy technique, length of hospital stay, and postoperative pain score did not differ significantly. After discharge, the median time to complete relief of pain tended to be shorter in the gasless group (5 days [range 1 to 15]) vs. the conventional group (8 days [range 1 to 15]). The period to return to normal activity was shorter in the GLC group (6 days [range 1 to 15]) compared to the CLC group (8.5 days [range 1 to 15]) (P = 0.031). No differences were found in terms of fatigue, dizziness and nausea, and overall satisfaction with the outcome. This study demonstrates a significantly shorter convalescence after laparoscopic cholecystectomy by means of the gasless technique compared to the conventional CO2 technique. Exposure of the operative field was less than optimal using the gasless technique.
Assuntos
Colecistectomia Laparoscópica/efeitos adversos , Colecistectomia Laparoscópica/métodos , Colelitíase/cirurgia , Convalescença , Pneumoperitônio Artificial/efeitos adversos , Pneumoperitônio Artificial/métodos , Adulto , Idoso , Colecistectomia Laparoscópica/instrumentação , Colecistectomia Laparoscópica/psicologia , Tontura/etiologia , Fadiga/etiologia , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Náusea/etiologia , Medição da Dor , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/etiologia , Satisfação do Paciente , Pneumoperitônio Artificial/instrumentação , Pneumoperitônio Artificial/psicologia , Fatores de Tempo , Resultado do TratamentoAssuntos
Potenciação de Longa Duração/fisiologia , Dor/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia , Potenciais de Ação/fisiologia , Animais , Humanos , Fibras Nervosas/fisiologia , Nociceptores/patologia , Nociceptores/fisiopatologia , Dor/patologia , Células do Corno Posterior/patologia , Células do Corno Posterior/fisiopatologia , Traumatismos da Medula Espinal/patologia , Transmissão Sináptica/fisiologiaRESUMO
Extracellular recordings of wide dynamic range neurones in the dorsal horn driven by electrical stimulation of the sciatic nerve were performed in intact urethane-anaesthetized Sprague-Dawley rats. The electrically evoked neuronal responses were defined as A- and C-fibres responses according to latencies, and the effect of a deep nociceptive conditioning stimulus induced by 200 microg capsaicin (8-methyl-N-vanillyl-6-noneamide) injected into the contralateral gastrocnemius-soleus muscle was studied for at least 30 min. Independent of the size and location of the receptive field of the neurone under study, a clear inhibition of the neuronal responses was observed. The electrically evoked C-fibre responses were inhibited to 53% of baseline 15-30 min after injection of capsaicin. This inhibition was only slightly attenuated by 125 nmol of the alpha-adrenoceptor antagonist phentolamine or 250 nmol of the opioid receptor antagonist naloxone applied directly onto the spinal cord when the two compounds were administered separately 5 min before capsaicin. In contrast, when a mixture of the two compounds was given 5 min before capsaicin, the effect of capsaicin was completely abolished. These results indicate that activation of the capsaicin-sensitive afferents in the gastrocnemius-soleus muscle inhibits the electrically evoked C-fibre responses in the dorsal horn by activating noradrenergic and opioidergic inhibitory systems. Moreover, our data indicate that the activation of these two systems following injection of capsaicin has a sub-additive inhibitory effect on the wide dynamic range neurones in the spinal cord. We conclude that only one of these systems is sufficient for the inhibition to occur.
Assuntos
Capsaicina/farmacologia , Inibição Neural/efeitos dos fármacos , Inibição Neural/fisiologia , Vias Neurais/efeitos dos fármacos , Vias Neurais/metabolismo , Nociceptores/efeitos dos fármacos , Nociceptores/metabolismo , Norepinefrina/metabolismo , Peptídeos Opioides/metabolismo , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Antagonistas Adrenérgicos alfa , Animais , Feminino , Fibras Nervosas/efeitos dos fármacos , Fibras Nervosas/metabolismo , Vias Neurais/citologia , Nociceptores/citologia , Fentolamina/farmacologia , Células do Corno Posterior/citologia , Células do Corno Posterior/efeitos dos fármacos , Células do Corno Posterior/metabolismo , Ratos , Ratos Sprague-Dawley , Medula Espinal/citologiaRESUMO
We have published several reports on long-term potentiation (LTP) in single spinal wide dynamic range (WDR) neurons (responding to both innocuous and noxious stimuli) in urethane-anaesthetised rats. The protocol presented here, with single unit recordings of dorsal horn neurons before and after a nociceptive conditioning stimulation, may be useful in many electrophysiological studies of plastic changes in the spinal cord, such as LTP. We invite others to use this protocol for the study of spinal plasticity. Findings using this technique may be relevant for the understanding of changes in nociceptive transmission, induction of central sensitisation and maybe even in mechanisms of pathological pain and chronic pain states. We describe modified and alternative protocols for the study of LTP mechanisms under different conditions in intact and in spinalised animals, and after natural noxious stimuli. We present a novel method minimising peripheral influence of afferent input induced by antidromic neurogenic inflammation or inflammatory changes following a natural noxious stimulation. This is made possible by dissection of the sciatic nerve at two separate locations and local anaesthetic block distal to the stimulation site.
Assuntos
Potenciação de Longa Duração , Neurônios Aferentes/fisiologia , Medula Espinal/citologia , Anestésicos Locais/farmacologia , Animais , Condicionamento Operante , Feminino , Bloqueio Nervoso , Nociceptores/fisiologia , Dor/fisiopatologia , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/cirurgiaRESUMO
In this study extracellular recordings of nociceptive dorsal horn neurones driven by electrical stimulation of the sciatic nerve were performed in intact urethane-anaesthetized Sprague-Dawley rats. Spikes 0-40, 40-250 and 250-800 ms after stimulus were defined as A- and C-fibre responses and post-discharge, respectively, and the effect of 200 microg capsaicin (8-methyl-N-vanillyl-6-noneamide) injected into the contralateral gastrocnemius-soleus muscle was investigated. In most cells tested, regardless of the size or location of their receptive fields, the injection of capsaicin caused a clear inhibition of the electrically evoked C-fibre responses. In animals with intact descending pathways the mean C-fibre response was inhibited to 51% of baseline 15 min after injection of capsaicin. In contrast, when capsaicin was given during cold block of the spinal cord between the brainstem and the site of recording in the dorsal horn, the same response was inhibited to 91% of baseline. A significant interaction between cold block and capsaicin was detected. We conclude that stimulation of capsaicin-sensitive afferents in the deep tissue in the hind limb can inhibit the electrically evoked C-fibre responses in the dorsal horn by activating inhibitory descending projections from higher centres. The model presented here may be an important tool for further investigations of the endogenous descending antinociceptive system.
Assuntos
Capsaicina/farmacologia , Fibras Nervosas/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Vias Aferentes/efeitos dos fármacos , Vias Aferentes/patologia , Animais , Capsaicina/administração & dosagem , Temperatura Baixa , Estado de Descerebração , Estimulação Elétrica , Feminino , Injeções Intramusculares , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/inervação , Neurônios/efeitos dos fármacos , Nociceptores/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Medula Espinal/fisiopatologia , Medula Espinal/ultraestruturaRESUMO
Plasticity in pain control systems may play an important role in clinical pain and some mechanisms of plasticity may be similar to those involved in learning. In this study we investigate the importance of alpha-amino-3-hydroxy-5-methylisoxazole-4-proprionic acid (AMPA) and N-methyl-D-aspartate (NMDA) receptors for the maintenance of long-term potentiation (LTP) in wide dynamic range (WDR) neurons. Doses of 6-nitro-7-sulphomoylbenzoylquinoxaline-2,3-dione disodium (NBQX) and D-Q-amino-5-phosphonopentanoic acid (D-AP5) equipotent in reducing C-fiber mediated responses in controls, reduced the established LTP by about 50 and 80%, respectively. The drug effect lasted less than 1 h in controls. After induction of LTP, NBQX caused a reversible reduction of the potentiation. D-AP5, however, caused a stronger attenuation of the LTP, outlasting the effect of the drug in controls. We suggest that both pre-emptive analgesia preventing LTP induction and an early reduction of the excitation of neurons is important for the inhibition of LTP and central sensitization. Thus, it is possible that an early antinociceptive treatment preventing an excessive excitation of neurons in the dorsal horn may be of importance in preventing longlasting and pathological pain states.
Assuntos
Potenciação de Longa Duração/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Receptores de Glutamato/metabolismo , 2-Amino-5-fosfonovalerato/farmacologia , Animais , Antagonistas de Aminoácidos Excitatórios/farmacologia , Feminino , Potenciação de Longa Duração/fisiologia , Neurônios/metabolismo , Quinoxalinas/farmacologia , Ratos , Ratos Sprague-DawleyRESUMO
We report long-term potentiation (LTP) in single spinal wide dynamic range (WDR) neurons in urethane-anaesthetized spinalized rats with a complete neuromuscular blockade. Peripheral influences were excluded by a complete lidocaine block distal to the stimulation site on the sciatic nerve. As previously shown A-beta fibre evoked responses were not increased by the tetanic stimulation when there was a neuromuscular blockade during the experiment. Spinalization, excluding influences from supraspinal structures, increased all firing responses, and the LTP of C-fibre evoked responses when calculated in number of action potentials compared to intact animals and to previous studies. Furthermore, an LTP of the post discharge was observed after spinalization. An LTP of the post discharge has previously not been reported. Therefore, we conclude that LTP in the dorsal horn normally seems to be inhibited by descending pathways.
Assuntos
Potenciação de Longa Duração , Bloqueio Nervoso , Bloqueio Neuromuscular , Neurônios/fisiologia , Medula Espinal/fisiologia , Análise de Variância , Animais , Pressão Sanguínea/fisiologia , Estado de Descerebração , Estimulação Elétrica , Potenciais Evocados/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Fibras Nervosas/fisiologia , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/fisiologia , Medula Espinal/citologiaRESUMO
A short-lasting tetanic sciatic nerve stimulation that previously has been shown to be nociceptive only during the stimulation, induces long-term potentiation (LTP) of nociceptive evoked responses in wide dynamic range neurons in the dorsal horn of rats. The LTP may contribute to the process of central sensitization. We have shown that the tetanic conditioning stimulation with muscular contractions induces LTP of both Abeta- and C-fibre evoked responses. However, the same stimulation during muscular paralysis induces LTP only of C-fibre evoked responses. In the present study, we investigated the effects of this conditioning stimulation with or without muscular paralysis in behavioural tests in rats. Conditioning stimulation with muscular contractions caused a significant reduction of weight borne on the stimulated side, suggesting muscular soreness and peripheral sensitization. Conditioning stimulation during neuromuscular paralysis, which only has given LTP of C-fibre evoked responses in intact animals, caused no change in the weight borne on the stimulated side, suggesting less or even absence of allodynia. However, in these animals the response temperature in the hot plate test was increased both on the stimulated and on the contralateral side compared to sham-operated rats. In view of our recent results indicating that a descending inhibition reduces the expression of LTP in dorsal horn cells, and the suggestion by others that long-term descending inhibition may override a segmental facilitation, it is suggested that an increased long-lasting endogenous nociceptive inhibition is induced after LTP-inducing stimulation. This is an interesting parallel to stimulation-induced analgesia in humans. Copyright 1999 European Federation of Chapters of the International Association for the Study of Pain.
RESUMO
The aim of the present study was to investigate whether data on location and distribution of intracranial cysts in a large patient population may explain why and how such cysts are formed. We investigated 123 patients with 129 intracranial cysts, consecutively admitted to the Department of Neurosurgery in Bergen 1988-97. Data were analyzed with regard to intracranial location and gender distribution. Cysts were much more commonly located in the temporal fossae than one would expect if the distribution were random; 68.1% of patients had temporal cysts. We suggest a theory that may explain how mal-development of the leptomeninges may contribute to the formation of cysts, and why such cysts are more common in the temporal fossae. Temporal cysts were significantly more frequent in males than in females (3.9:1), while cysts of other locations did not show preponderance for a specific gender. New in this study is the interesting connection between gender distribution and sidedness: the significant predominance of left-sided temporal cysts was found only in males. In patients with a unilateral temporal cyst, the left/right ratio was 2.0:1 (males 44 left and 20 right, females eight left and six right). We discuss whether the preponderance of left-sided temporal cysts in males can be explained by a gender specific developmental failure, as previously suggested for dyslexia.
Assuntos
Cistos Aracnóideos/diagnóstico , Adolescente , Adulto , Idoso , Cistos Aracnóideos/radioterapia , Cistos Aracnóideos/cirurgia , Criança , Pré-Escolar , Feminino , Lateralidade Funcional , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Tomografia Computadorizada por Raios XRESUMO
LTP is often studied as a model of synaptic plasticity. Plasticity in pain control systems may involve mechanisms similar to those involved in learning. We recently reported LTP of both the A beta and C-fibre evoked responses of single dorsal horn neurons after a tetanic stimulation of the sciatic nerve, lasting for at least 6 h. In the present paper we show that identical stimulation induced LTP only of the C-fibre evoked response after blockade of muscular contractions during the tetanus. The C-fibre evoked response increased significantly less after pretreatment with either the AMPA antagonist NBQX or the NMDA antagonist D-AP5 (mean increase 33%) than in untreated animals (105%, p < 0.001), indicating that both AMPA and NMDA receptor stimulation are involved in the induction of LTP.
Assuntos
Potenciação de Longa Duração/fisiologia , Contração Muscular/fisiologia , Dor/fisiopatologia , Receptores de AMPA/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia , Medula Espinal/fisiologia , 2-Amino-5-fosfonovalerato/farmacologia , Análise de Variância , Animais , Antagonistas de Aminoácidos Excitatórios/farmacologia , Feminino , Quinoxalinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de AMPA/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/efeitos dos fármacosRESUMO
Plasticity in the central nervous system may play an important role in clinical pain. The present study shows that long-term potentiation (LTP) may be induced in single wide dynamic range (WDR) neurons in the dorsal horn after high-frequency stimulation of the sciatic nerve in intact urethane anaesthetized rats. Extracellular recordings of firing responses after single pulse stimuli were made. The high-frequency conditioning stimulus increased the A beta- and C-fibre-mediated firing responses to single pulse stimuli by 60 and 130%, respectively, for more than 6 h. This finding supports a role for WDR neurons in 'nociceptive memory' in the dorsal horn. The model presented here may be an important tool for further investigations of mechanisms of plasticity within the dorsal horn.
Assuntos
Potenciação de Longa Duração , Fibras Nervosas/fisiologia , Neurônios/fisiologia , Dor/fisiopatologia , Nervo Isquiático/fisiologia , Medula Espinal/fisiologia , Vias Aferentes/fisiologia , Animais , Condicionamento Psicológico , Estimulação Elétrica , Potenciais Evocados , Feminino , Memória/fisiologia , Ratos , Ratos Sprague-Dawley , Fatores de TempoRESUMO
Data from 95 adult patients (43 males, 52 females) treated with ventriculoperitoneal shunts during an 8-year period were analyzed to investigate risk factors in shunt surgery. All patients were seen in the authors' department and were grouped according to the cause or type of hydrocephalus. The operating surgeons were divided into two categories: specialists and residents. The shunts were classified as single- (Orbis-Sigma) or multicomponent (Holter or Hakim) systems. Two types of unfavorable events were recognized: complications and shunt malfunction. A total of 143 surgical procedures (implantations and revisions) were performed in the 95 patients; 24 patients had their shunts revised, and there were 13 complications (one fatal, five severe) resulting from the shunt surgery. The following observations were statistically significant: 1) patients with normal pressure hydrocephalus had no complications from shunt surgery; 2) the number of shunt malfunctions was lower in patients with intracranial hemorrhages than in the other groups; 3) residents performed a higher number of inadequate operations than did specialists; and 4) the infection rate was higher among patients operated on by residents. The choice of shunt type, the perioperative use of antibiotics, and the degree of surgical emergency were not correlated with complication or failure rates.
Assuntos
Competência Clínica , Hidrocefalia/cirurgia , Complicações Pós-Operatórias/cirurgia , Derivação Ventriculoperitoneal/instrumentação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/cirurgia , Hemorragia Cerebral/etiologia , Hemorragia Cerebral/cirurgia , Desenho de Equipamento , Falha de Equipamento , Feminino , Humanos , Hidrocefalia/etiologia , Hidrocefalia de Pressão Normal/etiologia , Hidrocefalia de Pressão Normal/cirurgia , Masculino , Pessoa de Meia-Idade , Equipe de Assistência ao Paciente , Complicações Pós-Operatórias/etiologia , ReoperaçãoRESUMO
The variation in skin prick test (SPT) results was evaluated clinically during terfenadine treatment in 39 adult patients with pollen rhinitis. A change in the perceived state of the patient as regards sensitization to a specific pollen allergen or atopic constitution was judged to be clinically important. A randomized, double-blind, crossover design was used, comprising 2 weeks on terfenadine 120 mg once a day and 2 weeks on placebo. SPT for two pollen allergens and histamine (10 mg/ml) were evaluated at the start of the study and at the end of each period. When SPT was used as a discovery test and liberal definitions were applied, predictive values for a positive test were 100%. 1-Sensitivity ranged between 10 and 54% with substantially lower values when a histamine wheal reaction was noted. The inhibitory effect of terfenadine was detectable 2 weeks after withdrawal as a reduction in the median of the mean diameter for the histamine-induced wheal response of 1 mm (0-1.5). The data implied that a positive SPT is reliable when liberal definitions are adopted for sensitization and atopy; a negative SPT is presumably reliable when the measurement artifact is considered and the wheal reaction to histamine is detectable.
Assuntos
Alérgenos , Pólen , Rinite Alérgica Perene/diagnóstico , Rinite Alérgica Perene/tratamento farmacológico , Testes Cutâneos , Terfenadina/uso terapêutico , Adolescente , Adulto , Alérgenos/efeitos adversos , Alérgenos/imunologia , Estudos Cross-Over , Método Duplo-Cego , Hipersensibilidade a Drogas/imunologia , Humanos , Hipersensibilidade Imediata/induzido quimicamente , Hipersensibilidade Imediata/imunologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Rinite Alérgica Perene/imunologia , Sensibilidade e Especificidade , Fatores de Tempo , Resultado do TratamentoRESUMO
Thirty-two patients with 41 injured arteries were operated upon during a period of 12 years. Three quarters were men, and the median age was 33 years. Accompanying lesions were seen in 87.5% of the patients. Nearly half the lesions were related to blunt trauma. Occupational accidents constituted the largest group. The diagnosis was made on clinical grounds in most cases. The median time lapse from trauma to operation was 5 hours. The principles of treatment were those that are generally accepted. No patients died, the amputation rate was 12.5%. Median follow-up was 8 months. A successful arterial reconstruction contributed to a good functional result. Postreconstruction thrombosis of arteries were found to occur within the first hours or days after reconstruction. Late thrombosis was rare and the overall long-time patency was 61.4%. Patency of repair of upper limb small vessels was 54.5%.