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1.
Clin Neurophysiol ; 123(7): 1383-90, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22153667

RESUMO

OBJECTIVE: To investigate motor cortical map patterns in children with diplegic and hemiplegic cerebral palsy (CP), and the relationships between motor cortical geometry and motor function in CP. METHODS: Transcranial magnetic stimulation (TMS) was used to map motor cortical representations of the first dorsal interosseus (FDI) and tibialis anterior (TA) muscles in 13 children with CP (age 9-16 years, 6 males.) The Gross Motor Function Measure (GMFM) and Melbourne upper extremity function were used to quantify motor ability. RESULTS: In the hemiplegic participants (N = 7), the affected (right) FDI cortical representation was mapped on the ipsilateral (N = 4), contralateral (N = 2), or bilateral (N = 1) cortex. Participants with diplegia (N = 6) showed either bilateral (N = 2) or contralateral (N = 4) cortical hand maps. The FDI and TA motor map center-of-gravity mediolateral location ranged from 2-8 cm and 3-6 cm from the midline, respectively. Among diplegics, more lateral FDI representation locations were associated with lower Melbourne scores, i.e. worse hand motor function (Spearman's rho = -0.841, p = 0.036). CONCLUSIONS: Abnormalities in TMS-derived motor maps cut across the clinical classifications of hemiplegic and diplegic CP. The lateralization of the upper and lower extremity motor representation demonstrates reorganization after insults to the affected hemispheres of both diplegic and hemiplegic children. SIGNIFICANCE: The current study is a step towards defining the relationship between changes in motor maps and functional impairments in CP. These results suggest the need for further work to develop improved classification schemes that integrate clinical, radiologic, and neurophysiologic measures in CP.


Assuntos
Mapeamento Encefálico/métodos , Paralisia Cerebral/fisiopatologia , Avaliação da Deficiência , Vias Eferentes/fisiopatologia , Córtex Motor/fisiopatologia , Estimulação Magnética Transcraniana/métodos , Adolescente , Tornozelo/fisiopatologia , Criança , Potencial Evocado Motor/fisiologia , Feminino , Lateralidade Funcional/fisiologia , Mãos/fisiopatologia , Hemiplegia/fisiopatologia , Humanos , Masculino
2.
Pediatrics ; 108(5): 1062-71, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11694682

RESUMO

BACKGROUND: Focal spasticity of the gastrocnemius-soleus muscles causes equinus gait in children with cerebral palsy (CP). Botulinum toxin type A (BTX-A), a neuromuscular blocking agent, reduces muscle tone/overactivity in dystonia, stroke, and CP. OBJECTIVE: A prospective, open-label, multicenter clinical trial evaluated the long-term safety and efficacy of repeated intramuscular injections of BTX-A on equinus gait in CP children. METHODS: Nine centers enrolled 207 children. BTX-A injections (4 U/Kg) were given approximately every 3 months (maximum dose 200 U per treatment). Outcome measures included a Physician Rating Scale of gait, ankle range of motion measurements, and the incidence and profile of adverse events. RESULTS: One hundred fifty-five (75%) of 207 children completed at least 1 year with a total of 302 patient years of BTX-A treatment. The mean duration of BTX-A exposure was 1.46 years per patient. Dynamic gait pattern on the Physician Rating Scale improved in 46% of patients (86/185) at first follow-up. The response was maintained in 41% to 58% of patients for 2 years. Both gait pattern and ankle position improved at every visit. The most common treatment-related adverse events included increased stumbling, leg cramps, leg weakness, and calf atrophy in 1% to 11% of patients. No treatment-related serious adverse events were reported. Only 6% (7/117) of patients with pre- and postantibody samples had both detectable antibodies and a subsequent treatment failure. CONCLUSION: BTX-A proved both safe and effective in the chronic management of focal muscle spasticity in children with equinus gait.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Paralisia Cerebral/complicações , Pé Equino/terapia , Fármacos Neuromusculares/uso terapêutico , Bloqueio Neuromuscular/métodos , Adolescente , Pé Equino/etiologia , Feminino , Marcha , Humanos , Masculino , Estudos Prospectivos
3.
Orthopedics ; 24(4): 339-43, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11332961

RESUMO

This prospective study evaluated the correlation between plain radiographs, magnetic resonance imaging (MRI), and diagnostic arthroscopy in the staging of avascular necrosis of the femoral head. Fifty-two hips in 46 patients were prospectively staged using radiographic and MRI staging systems. Patients subsequently underwent hip arthroscopy to visualize the articular surface prior to considering salvage of the femoral head and debride delaminated osteochondral fragments. Weighted Kappa analysis revealed only moderate correlation between MRI and plain radiographs (K=.11), MRI and arthroscopy (K=.21), and plain radiographs and arthroscopy (K=.19). Six (46%) of 13 patients with a radiographically apparent subchondral fracture demonstrated collapse of the articular surface at arthroscopy. Four (24%) of 17 hips with >2 mm of collapse of the femoral head on plain radiographs demonstrated fragmentation of the osteochondral surface of the femoral head at arthroscopy. In 5 patients with flattening of the femoral head, 3 patients had delamination of both the femoral and acetabular surfaces. In regard to labral pathology, 5 of 22 post-collapse hips also had large bucket handle tears of the labrum. Arthroscopy of the hip revealed osteochondral degeneration that was not detected by plain radiographs or MRI in 36% of post-collapse femoral heads.


Assuntos
Artroscopia , Necrose da Cabeça do Fêmur/diagnóstico , Adolescente , Adulto , Feminino , Necrose da Cabeça do Fêmur/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radiografia
5.
J South Orthop Assoc ; 10(1): 32-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12132840

RESUMO

We assessed the efficacy of progressive soft tissue distraction using monolateral external fixation in the management of severe knee flexion contractures. We prospectively evaluated 10 knee deformities in seven pediatric patients. After gradual distraction using the modified Orthofix Limb Reconstruction System (LRS), most recent functional status and knee range of motion were determined. This treatment was applied to 10 extremities in seven patients, ranging in age from 2 to 16 years. Diagnoses included arthrogryposis (4), sickle cell disease (1), previous sepsis (1), and congenital pterygium (1). Average preoperative flexion contracture was 80.5 degrees. Each patient achieved full extension. There was one recurrence, despite bracing, which was managed with replacement of the fixator and soft tissue procedures. Management of knee flexion contractures using a monolateral fixator appears to be a viable alternative to extensive release or femoral osteotomy. Long-term follow-up will be essential to assess the overall risk of recurrence and complications.


Assuntos
Contratura/cirurgia , Articulação do Joelho , Osteogênese por Distração , Adolescente , Criança , Pré-Escolar , Contratura/fisiopatologia , Humanos , Articulação do Joelho/fisiopatologia , Estudos Prospectivos , Amplitude de Movimento Articular
6.
J Orthop Res ; 18(1): 156-63, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10716292

RESUMO

An acute in vivo preparation of the microvasculature of the rabbit ear was used to evaluate the functional role of alpha1 (alpha1)-adrenoceptor subtypes in thermoregulatory microcirculation. The effect of alpha1-adrenoceptor subtype blockade on phenylephrine-induced vasoconstriction was assessed with the alpha1A, alpha1B, and alpha1D-adrenoceptor-selective antagonists 5-methyl-urapidil (10(-8) M), chloroethylclonidine (10(-5) M), and 8-[2-[4(2-methoxyphenyl)-1-piperazinyl]ethyl]-8-azaspirol[4.5]deca ne-7,9-dione dihydrochloride (BMY7378) (10(-6) M), respectively. The results demonstrated that pretreatment of the ear microvasculature with 5-methyl-urapidil or BMY7378 shifted the phenylephrine concentration-response curve rightward and significantly changed the log of the phenylephrine concentration, causing half-maximum stimulation (EC50) in arterioles (p < 0.05). BMY7378 shifted the phenylephrine concentration-response curve of the arteriovenous anastomoses about 100-fold rightward (p < 0.05). All three alpha1-adrenoceptor antagonists eliminated the vasoconstrictive effects of phenylephrine on venules. The results indicate that the ear microvasculature has a heterogenous distribution of alpha1-adrenoceptor subtypes. The alpha1A and alpha1D-adrenoceptor subtypes appear to have a greater influence on constrictive function in arterioles, whereas the alpha1D-adrenoceptor is the dominant constrictor of arteriovenous anastomoses. In general, the alpha1-adrenoceptor does not play a major vasoconstrictor role in venules. Chloroethylclonidine, an irreversible alpha1B-adrenoceptor antagonist, induced contractile responses in the ear microvasculature, probably due to its alpha2-adrenoceptor agonist effects. This study extended our understanding of the adrenergic receptor control mechanisms of a cutaneous thermoregulatory end organ characterized by two parallel perfusion circuits providing nutritional and thermoregulatory functions.


Assuntos
Regulação da Temperatura Corporal , Orelha/irrigação sanguínea , Receptores Adrenérgicos alfa 1/fisiologia , Vasoconstrição , Animais , Anastomose Arteriovenosa/efeitos dos fármacos , Clonidina/análogos & derivados , Clonidina/farmacologia , Relação Dose-Resposta a Droga , Masculino , Microcirculação/efeitos dos fármacos , Fenilefrina/farmacologia , Piperazinas/farmacologia , Coelhos , Receptores Adrenérgicos alfa 1/classificação , Vasoconstrição/efeitos dos fármacos
7.
J Hand Surg Am ; 25(2): 282-90, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10722820

RESUMO

This study was designed to detail the history and symptoms of symptomatic radial artery vaso-occlusive disease and to evaluate the results of radial artery reconstruction. Thirteen patients with symptomatic vaso-occlusive disease of the radial artery unresponsive to management by nonoperative modalities were managed with arterial reconstruction. All cases were treated with reversed interpositional vein grafting from the radial artery in the forearm (end-to-side) to the deep arch distally (end-to-end). Patients completed preoperative and postoperative assessments of symptoms and function, cold sensitivity (cold intolerance), and digital microvascular perfusion (isolated cold stress test evaluation with laser Doppler fluxmetry). At the follow-up examination all vascular grafts were patent, as determined by Allen's testing and Doppler ultrasound. The patients reported symptoms and functional status that demonstrated significant improvement following reconstruction. Microvascular evaluations demonstrated a significant improvement in digital microvascular perfusion as assessed by laser Doppler fluxmetry and digital temperature recordings with a resultant resolution of ischemic pain, numbness, and ulceration.


Assuntos
Arteriopatias Oclusivas/cirurgia , Mãos/irrigação sanguínea , Artéria Radial/cirurgia , Veia Safena/transplante , Procedimentos Cirúrgicos Vasculares/métodos , Adolescente , Adulto , Análise de Variância , Anastomose Cirúrgica , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/fisiopatologia , Feminino , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Artéria Radial/diagnóstico por imagem , Fluxo Sanguíneo Regional/fisiologia , Estatísticas não Paramétricas , Resultado do Tratamento , Ultrassonografia de Intervenção
8.
J Pediatr Orthop ; 20(1): 108-15, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10641699

RESUMO

Increased gastrocnemius/soleus muscle tone in children with cerebral palsy may cause an equinus of the ankle. Botulinum toxin type A (BTX), a neuromuscular blocking agent, reduces muscle tone in various neuromuscular disorders. The safety and short-term efficacy of BTX injections were evaluated in a prospective, 3-month, double-blind, randomized clinical trial involving 114 children with cerebral palsy and dynamic equinus foot deformity. Outcome was determined by observational gait analysis, ankle range-of-motion measurements, and quantification of muscle denervation by nerve conduction. Patients in the BTX group demonstrated improved gait function and partial denervation of the injected muscle. No serious adverse events were reported.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Paralisia Cerebral/complicações , Perna (Membro) , Espasticidade Muscular/tratamento farmacológico , Espasticidade Muscular/etiologia , Fármacos Neuromusculares/uso terapêutico , Bloqueio Neuromuscular , Adolescente , Criança , Pré-Escolar , Método Duplo-Cego , Pé Equino/tratamento farmacológico , Pé Equino/etiologia , Pé Equino/fisiopatologia , Marcha , Humanos , Espasticidade Muscular/fisiopatologia , Estudos Prospectivos , Amplitude de Movimento Articular
11.
J South Orthop Assoc ; 9(4): 254-61, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-12141188

RESUMO

The purposes of this study were to evaluate how accurately current imaging modalities predict the quality of the articular surface in avascular necrosis (AVN) of the femoral head and to provide arthroscopic correlation to current staging modalities. An arthroscopic classification system, derived from the work of Marcus et al, was used to prospectively stage the articular surface in 23 hips with AVN using plain radiographs, magnetic resonance imaging (MRI), and arthroscopy. There was little correlation between all three diagnostic modalities. These findings were not statistically significant. Patients with stage IV disease had the widest variation in the appearance of the articular surface. This study shows poor correlation in the staging of AVN using current imaging techniques. Magnetic resonance imaging has been shown to be inadequate at assessing the articular cartilage. Therefore, either arthroscopy or direct visualization is required for accurate evaluation and staging, especially in stage IV disease.


Assuntos
Artroscopia , Necrose da Cabeça do Fêmur/patologia , Feminino , Necrose da Cabeça do Fêmur/diagnóstico por imagem , Articulação do Quadril/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos , Radiografia
12.
J South Orthop Assoc ; 8(2): 93-7, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10472826

RESUMO

Congenital dislocation of the knee (CDK) is rare and includes a spectrum of hyperextension disorders of the knee. Early recognition of CDK is important, and careful evaluation is required to rule out associated hip deformity. Early manipulation, combined with splinting and casting, is the mainstay of initial treatment. Patients with seemingly fixed contractures may respond rapidly to serial casting and then can be placed in a Pavlik harness. Severe recalcitrant deformities or late presentation of the deformity may require surgical release. We highlight the importance of diagnostic categorization, show management options, and provide an overview of this rare but clinically significant problem. We present two case reports that illustrate the full range of management options.


Assuntos
Luxações Articulares/congênito , Articulação do Joelho/cirurgia , Humanos , Recém-Nascido , Luxações Articulares/fisiopatologia , Articulação do Joelho/fisiopatologia , Masculino , Amplitude de Movimento Articular
13.
Microsurgery ; 19(4): 181-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10336247

RESUMO

This study assessed the accuracy of arteriography and laser Doppler perfusion imaging (LDPI) as predictors of digital ischemia and correlated upper extremity symptoms, function, and nutritional flow with arteriographic and laser Doppler assessments. Multiple-level occlusive disease was documented in 25 hands (23 patients) by arteriography. LDPI demonstrated one or more hypoperfused digits in 17 hands. Patient questionnaires were used to assess upper extremity symptoms, pain, cold sensitivity, and function. Spearman correlation coefficients indicated that arteriography is a poor indicator of nutritional perfusion as measured by LDPI. Neither arteriography or laser Doppler perfusion imaging served as an indicator of the severity of cold intolerance. However, upper extremity symptoms and functional status correlated with both laser Doppler measurements and the level of cold sensitivity. Laser Doppler perfusion imaging and arteriographic analysis provide complimentary data in the evaluation of upper extremity ischemia.


Assuntos
Braço/irrigação sanguínea , Isquemia/diagnóstico , Adolescente , Adulto , Idoso , Angiografia , Temperatura Baixa , Feminino , Mãos/irrigação sanguínea , Humanos , Isquemia/fisiopatologia , Fluxometria por Laser-Doppler , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional
14.
J South Orthop Assoc ; 8(3): 214-7, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-12132867

RESUMO

Although replantation of completely amputated wrists and forearms is now commonplace, in 1965 the replantation of this "wrist level" amputation was the first reported in the western world. The details of the technique used are contrasted with current standard of care.


Assuntos
Amputação Traumática/história , Traumatismos do Antebraço/história , Reimplante/história , Amputação Traumática/cirurgia , Traumatismos do Antebraço/cirurgia , História do Século XX , Humanos , Reimplante/métodos
15.
J South Orthop Assoc ; 8(1): 47-52, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-12132853

RESUMO

We have presented a technique for reconstruction of the central band of the interosseous membrane in conjunction with surgical repair of the distal radial joint and radial head prosthesis. With this technique, we address all three anatomic structures that provide longitudinal stability of the forearm, specifically, (1) radial head replacement, (2) interosseous membrane reconstitution, and (3) TFCC repair.


Assuntos
Fixação Interna de Fraturas/métodos , Ligamentos Articulares/lesões , Fraturas do Rádio/cirurgia , Rádio (Anatomia)/cirurgia , Osso Escafoide/lesões , Traumatismos do Punho/cirurgia , Cartilagem/cirurgia , Feminino , Antebraço , Humanos , Membranas/lesões , Pessoa de Meia-Idade , Recidiva
16.
J South Orthop Assoc ; 7(3): 192-7, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9781895

RESUMO

After upper extremity injury, pain on exposure to cold (cold sensitivity) is a significant problem. This cross-sectional observational study (1) assesses the incidence and prevalence of cold intolerance, (2) evaluates the relationship between functional status and degree of cold intolerance, and (3) correlates health-related quality of life (HRQL) with symptoms of cold intolerance. Patients in a tertiary care center completed questionnaires to document (1) cold sensitivity, (2) upper extremity pain, symptoms, and function, and (3) HRQL. Cold sensitivity was found to be associated with more functional limitations, greater pain, and reduced HRQL. As the severity of cold intolerance increased, functional limitations and pain increased and HRQL decreased. Cold intolerance has a profound effect on HRQL.


Assuntos
Traumatismos do Braço/complicações , Temperatura Baixa/efeitos adversos , Transtornos de Sensação/etiologia , Atividades Cotidianas , Adulto , Análise de Variância , Traumatismos do Braço/fisiopatologia , Estudos Transversais , Feminino , Fraturas Ósseas/complicações , Nível de Saúde , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Dor/fisiopatologia , Medição da Dor , Prevalência , Qualidade de Vida , Transtornos de Sensação/classificação , Transtornos de Sensação/fisiopatologia , Transtornos de Sensação/psicologia , Fatores Sexuais , Fumar/efeitos adversos , Sensação Térmica/fisiologia
17.
J Hand Surg Am ; 23(5): 773-82, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9763249

RESUMO

Patients were evaluated before and after arterial reconstruction surgery (1) to define the physiology of the digital microcirculation in chronic subcritical ischemia, (2) to demonstrate the short-term effects of successful arterial reconstruction on microvascular flow, and (3) to document the effects of surgery on symptoms, function, and health-related quality of life. Arterial insufficiency was the result of a proximal reconstructible occlusive lesion, 1 or more distal unreconstructible occlusions, and secondary reactive vasospasm. Microvascular physiology was evaluated by monitoring digital temperatures, microvascular perfusion (laser Doppler fluxmetry) and perfusion patterns (laser Doppler perfusion patterns (laser Doppler perfusion imaging). Following successful vascular reconstruction, digital temperatures and microvascular perfusion improved significantly, approaching control levels. Although cold sensitivity was unchanged, symptoms decreased and upper extremity function and health-related quality of life improved after successful proximal reconstruction in patients with 2-level arterial occlusion.


Assuntos
Dedos/irrigação sanguínea , Mãos/irrigação sanguínea , Isquemia/cirurgia , Qualidade de Vida , Punho/irrigação sanguínea , Adulto , Análise de Variância , Anastomose Cirúrgica/métodos , Estudos de Coortes , Feminino , Seguimentos , Humanos , Fluxometria por Laser-Doppler , Masculino , Microcirculação/fisiologia , Pessoa de Meia-Idade , Artéria Radial/patologia , Artéria Radial/cirurgia , Resultado do Tratamento , Artéria Ulnar/patologia , Artéria Ulnar/cirurgia , Grau de Desobstrução Vascular/fisiologia , Procedimentos Cirúrgicos Vasculares/métodos
18.
J Hand Surg Am ; 23(5): 792-9, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9763251

RESUMO

The effects of transdermal nicotine-assisted smoking cessation on digital perfusion and health-related quality of life were assessed in 10 chronic smokers. Components of digital blood flow were evaluated by digital temperature and laser Doppler fluxmetry before, during, and after a standardized cold challenge. Nutritional flow was measured by vital capillaroscopy; a quantitative perfusion profile was obtained by laser Doppler perfusion imaging. A battery of validated measures were used to evaluate health-related quality of life. The microvascular response of smokers was evaluated before smoking cessation and at 2 and 7 days after smoking cessation and was compared with the response of nonsmoking controls. Results demonstrated that a (1) cutaneous microvascular perfusion was lower in smokers than nonsmokers, (2) the acute administration of transdermal nicotine did not decrease cutaneous perfusion, (3) smoking cessation and transdermal nicotine normalized digital microvascular perfusion by 7 days, and (4) transdermal nicotine and smoking cessation did not negatively impact health-related quality of life.


Assuntos
Dedos/irrigação sanguínea , Nicotina/administração & dosagem , Qualidade de Vida , Abandono do Hábito de Fumar/métodos , Administração Cutânea , Adulto , Análise de Variância , Regulação da Temperatura Corporal/fisiologia , Monóxido de Carbono/sangue , Feminino , Humanos , Masculino , Microcirculação/efeitos dos fármacos , Pessoa de Meia-Idade , Nicotina/efeitos adversos , Cooperação do Paciente , Fluxo Sanguíneo Regional
19.
J Cardiovasc Pharmacol ; 32(3): 349-56, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9733346

RESUMO

The role of nitric oxide (NO) in the control of arteriovenous anastomoses (AVAs) has not been studied in vivo in a thermoregulatory end organ. In this study, the effect of local inhibition of NO synthesis by NG-nitro-L-arginine methyl ester (L-NAME) on the microvasculature in the rabbit ear (n=12) was observed in vivo through a chronically implanted ear microvascular chamber. Ear cutaneous blood perfusion (CBP), total auricular arterial flow (TAF), and ear temperature were monitored simultaneously with the direct microvascular observations. Results revealed that intrafacial artery infusion of L-NAME produced significant vasoconstriction of arterioles, AVAs, and venules (p < 0.05). A decrease of ear blood perfusion also was demonstrated by changes of CBP, TAF, and surface temperature. The data provide evidence that basal generation of NO influences the vascular resistance in the thermoregulatory end organ. Moreover, endogenous NO production may be more important in regulating the AVA flow than is flow in other parts of the rabbit ear microvasculature. The effects of NO inhibition on ear microvasculature were not abolished by superior cervical ganglionectomy, indicating that NO production in the rabbit ear is not a neurally mediated mechanism. Further study with a short-term rabbit ear preparation showed that inhibition of NO production with L-NAME enhanced microvascular constrictive responses to extraluminal application of norepinephrine. NO thus appears to play a role of basal vasodilator in opposition to the basal adrenergic vasoconstrictor tone in the rabbit ear.


Assuntos
Anastomose Arteriovenosa/fisiologia , Regulação da Temperatura Corporal , Orelha/irrigação sanguínea , Óxido Nítrico/fisiologia , Receptores Adrenérgicos/fisiologia , Animais , Cães , Relação Dose-Resposta a Droga , Microcirculação/efeitos dos fármacos , NG-Nitroarginina Metil Éster/farmacologia , Norepinefrina/farmacologia , Coelhos , Vasoconstrição/efeitos dos fármacos
20.
Microsurgery ; 18(2): 129-36, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9674929

RESUMO

A rabbit ear model of the human digit was utilized to determine the vascular response to peripheral sympathectomy. Vascular responses were evaluated by subjecting chronically instrumented rabbits to a cold stress before and after sympathectomy surgery. The typical response to cold stress is for ear temperatures and auricular cutaneous perfusion to decrease during the cooling phase of the test and to increase toward baseline levels during the rewarming phase after cold exposure. Following peripheral sympathectomy, ear temperatures were significantly increased during both the cooling and rewarming phase of the cold stress test although overall ear perfusion and skin perfusion were not different from sham-operated rabbits. The responses observed in the rabbit ear following peripheral sympathectomy appear to mimic those noted in patients receiving digital peripheral sympathectomies for the treatment of refractory pain and ulceration. Peripheral sympathectomy may result in clinical improvements in patients because it improves both total digital and nutritional cutaneous blood flow. Peripheral sympathectomy in normal rabbit ears does not result in altered perfusion patterns with cold exposure although ear temperature is significantly higher. This pattern of changes suggests that the distribution of extremity perfusion is altered even though overall extremity perfusion and cutaneous perfusion per se are not significantly different from sham-operated controls. Complete sympathectomy was accompanied by a persistent increase in ear temperature and a dissociation between conductance and microvascular perfusion. Auricular conductance was transiently increased and then decreased to levels below preoperative control values. Microvascular perfusion is decreased immediately following amputation/replantation and thereafter increases.


Assuntos
Artérias/inervação , Regulação da Temperatura Corporal/fisiologia , Orelha/irrigação sanguínea , Simpatectomia , Veias/inervação , Animais , Temperatura Baixa , Modelos Animais de Doenças , Orelha/diagnóstico por imagem , Orelha/cirurgia , Fluxometria por Laser-Doppler , Masculino , Microcirculação/diagnóstico por imagem , Microcirculação/fisiopatologia , Coelhos , Valores de Referência , Fluxo Sanguíneo Regional , Ultrassonografia , Grau de Desobstrução Vascular/fisiologia
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